Vaccination for people who are immunocompromised

People who are immunocompromised have an increased risk of morbidity and mortality from many vaccine-preventable diseases.

A person can be immunocompromised as a result of:

• congenital or acquired disorders
• disease
• immunosuppressive medical treatment

All people who are immunocompromised, or people who may be immunocompromised in the future as a result of disease or treatment, need to have a thorough risk assessment to determine their level of immunocompromise.

People who are immunocompromised need their vaccination history assessed carefully and a plan for future vaccination made. Live vaccines may be contraindicated in these people, or the person may need extra doses of inactivated vaccines to protect against disease.

See Infographic. Vaccination for people who are immunocompromised.

Assessing the extent of immunocompromise

Vaccinating people who are immunocompromised can be challenging. It can be difficult to determine the extent to which a person is immunocompromised, because it depends on the underlying disease, medical treatment and other factors. The person may have:

• reduced protection from previous vaccination
• reduced response to vaccines, so they may need extra doses
• an increased risk of vaccine-preventable diseases or complications
• an increased risk of adverse events, particularly from live vaccines

When considering vaccinating people on immunosuppressive therapy, it is important to review the:

• mechanism, and duration of the effect on the immune system, of the medicine or other treatment
• consequence of using combination therapies — for example, corticosteroids and other immunosuppressive therapies such as DMARDs (disease-modifying anti-rheumatic drugs), which can contribute to the nature, extent and length of the immunocompromising condition
• anticipated duration of the person’s immunocompromised state, whether due to the therapy or the underlying disease

If there is uncertainty about how severely a person is immunocompromised and whether it is safe for them to receive a vaccine, do not vaccinate them. Seek expert advice from their treating physician or an immunisation specialist.

For more details about assessing the level of immunocompromise to determine whether people can receive live vaccines, see Use of specific live vaccines in people who are immunocompromised.

Assessing the need for extra vaccine doses

People who are immunocompromised may need extra doses of inactivated vaccines to optimise protection against specific diseases. An example is extra doses of pneumococcal vaccines for people with haematological malignancy.

People who have recovered from a period of being immunocompromised — such as after treatment for cancer or using immunosuppressive medication for an autoimmune disease — may also need extra doses of live or inactivated vaccines. See also Use of specific live vaccines in people who are immunocompromised.

To determine the need for additional doses, it may be useful to measure post-vaccination antibody titres in some circumstances, such as for adults or children who have received haematopoietic stem cell transplants (see Haematopoietic stem cell transplant recipients). 

However, reliable serological testing is not readily available or validated to measure vaccine-induced immunity for all vaccines. Use standardised serological correlates to interpret any results, and seek expert advice if needed. See also Laboratory testing to guide catch-up vaccination in Catch-up vaccination.

People who are immunocompromised are at risk of adverse events or vaccine-related disease if they receive a live vaccine.

Live vaccines include:

• BCG (bacille Calmette–Guérin) vaccine
• oral cholera vaccine (Vaxchora)
• Some Japanese encephalitis virus vaccines
• MMR (measles-mumps-rubella) vaccine
• mpox vaccine (JYNNEOS)
• rotavirus vaccine
• oral typhoid vaccine
• varicella vaccine
• yellow fever vaccine
• zoster vaccine (Zostavax)

Vaccine-related disease can be caused by unchecked infection (replication) by the live vaccine virus or bacteria. This is especially true for:

• BCG vaccine^1,2
• vaccines that contain measles, mumps, rubella^3,4 or varicella-zoster virus⁵

However, the risk of vaccine-related disease varies by vaccine and by individual.

It is important to carefully review people who are potentially immunocompromised for their suitability to receive a live vaccine.

Live vaccines are generally contraindicated for most people who are severely immunocompromised. If there is uncertainty about how severely a person is immunocompromised and whether it is safe for them to receive a vaccine, do not vaccinate them. Seek expert advice from their treating physician or an immunisation specialist.

Mpox MVA-BN vaccine (JYNNEOS) is a live-attenuated, replicant-deficient (unable to replicate in human cells) vaccine that is appropriate for use in immunocompromised people.

People who are severely immunocompromised

People who are severely immunocompromised should not receive live viral or live bacterial vaccines.

People who are severely immunocompromised include those who:

• have active leukaemia or lymphoma, or other generalised malignancy 
• have received recent chemotherapy or radiotherapy
• have HIV (certain people only)
• had a solid organ transplant or haematopoietic stem cell transplant less than 2 years ago, or are still immunocompromised or taking immunosuppressive drugs, or have graft-versus-host disease 
• are taking highly immunosuppressive therapy, including bDMARDs or tsDMARDs (biological or targeted synthetic disease-modifying anti-rheumatic drugs), or high-dose corticosteroids
• have certain autoimmune diseases, particularly if they are on highly immunosuppressive therapy
• have aplastic anaemia
• have congenital immunodeficiency

People on immunosuppressive therapy

People on immunosuppressive therapy should be carefully assessed to determine whether they can receive live vaccines. 

Live viral vaccines are contraindicated in people taking highly immunosuppressive therapy, including bDMARDs or tsDMARDs, or high-dose corticosteroids.

If there is any uncertainty about how severe the person’s immunocompromising condition is and whether they can safely receive live attenuated vaccines, do not vaccinate. Seek expert advice from their treating physician or an immunisation specialist.

People who may be only mildly immunocompromised include those who are receiving selected csDMARDs (conventional synthetic DMARDs) in low doses, either on their own or in combination with low-dose corticosteroids (<20 mg per day of prednisone-equivalent dose). These people can receive some live vaccines (for example, zoster vaccine) on advice from a specialist and after a risk assessment. 

Examples of low-dose csDMARDs are:

• methotrexate ≤0.4 mg per kg per week
• azathioprine ≤3.0 mg per kg per day 
• mercaptopurine ≤1.5 mg per kg per day

Also see Herpes zoster and People with autoimmune diseases and other chronic conditions.

People who are immunocompetent but expect a change to their immunity because of their existing illness may be able to receive MMR- and varicella-zoster virus–containing vaccines on a case-by-case basis on advice from a specialist and after a risk assessment.

People receiving corticosteroid therapy

Table. Recommended timing of live vaccine doses in adults and children taking corticosteroids shows the recommendations for when patients on corticosteroids can receive live vaccines, depending on the dose and duration of therapy. There are several different formulations of systemic corticosteroids (for example, prednisone, dexamethasone, cortisone, methylprednisolone) — the table refers to a prednisone-equivalent dose. Convert systemic doses of different formulations of systemic corticosteroids (such as dexamethasone, cortisone and methylprednisolone) to a prednisone-equivalent dose to assess a person’s suitability to receive live viral vaccines.

In general, the combination of corticosteroid therapy and other immunocompromising treatments or conditions is a contraindication to vaccination.

Live attenuated vaccines (such as MMR, MMRV [measles-mumps-rubella-varicella], zoster [Zostavax], varicella and yellow fever) may be unsafe in people receiving corticosteroid therapy. The dose and duration of therapy with corticosteroids, and use of corticosteroids in combination with other immunosuppressive therapies such as bDMARDs and tsDMARDs, determine the effects on the immune system (see People with autoimmune diseases and other chronic conditions).

Depending on the dose and duration of corticosteroid therapy, live attenuated vaccines may be safe to administer. An example is when a person is receiving corticosteroid therapy in low doses and this is the only risk factor for immunocompromise. See the relevant disease-specific chapters in this Handbook for specific exceptions and Table. Recommended timing of live vaccine doses in adults and children taking corticosteroids.

Another exception is zoster vaccine (Zostavax), which can be given to people ≥50 years of age taking low-dose corticosteroids (<20 mg per day of prednisone-equivalent dose), either alone or in combination with certain csDMARDs in low doses. At these doses, it is likely that the level of immunocompromise is not severe. Only vaccinate the person if a risk assessment, using the Live zoster vaccine (Zostavax) screening for contraindications tool, indicates that it is safe.

Once treatment with corticosteroids has ended, assess whether the person has other underlying immunocompromising disease or is receiving other immunosuppressive therapy that may influence whether they can receive vaccines, particularly live vaccines.

Inhaled and short-term corticosteroids

People who use inhaled corticosteroids alone (such as for asthma) and who have no other immunocompromising factors that would contraindicate vaccine use can receive live attenuated vaccines.

Pregnant women who received short-term antenatal corticosteroids — for example, during preterm labour — can receive inactivated vaccines where indicated (see Vaccination for women who are planning pregnancy, pregnant or breastfeeding).

Use of specific live vaccines in people who are immunocompromised

This section summarises information on the use of specific live vaccines in people who are immunocompromised. See also relevant disease-specific chapters for more details.

BCG vaccine (tuberculosis)

BCG vaccine is always contraindicated in people who are immunocompromised (see Tuberculosis).

Oral cholera vaccine

Travellers who are immunocompromised should not receive oral live attenuated cholera vaccine. Use the inactivated oral cholera vaccine instead (see Cholera).

Japanese encephalitis vaccine

People who are immunocompromised and need a Japanese encephalitis vaccine should not receive the live attenuated recombinant vaccine (Imojev). Use the inactivated vaccine (JEspect) instead (see Japanese encephalitis). 

MMR vaccines

MMR-containing vaccines are contraindicated in people who are significantly immunocompromised as a result of a medical condition.

MMR-containing vaccines are contraindicated in people receiving high-dose systemic immunosuppressive therapy, such as chemotherapy, radiation therapy or oral corticosteroids.

Children and adults with HIV who are asymptomatic and have an adequate age-specific CD4⁺ count may receive MMR-containing vaccines. See Measles, Mumps and Rubella.

Mpox vaccine

People who are immunocompromised and need an mpox vaccine can receive the replication-deficient mpox vaccine, MVA-BN (JYNNEOS), although immune response may be reduced. Specialist medical advice may be required, including consideration of additional doses for those at ongoing risk of exposure (See also Mpox).

Oral typhoid vaccine

Travellers who are immunocompromised should not receive oral live attenuated typhoid vaccine. Use the inactivated parenteral Vi polysaccharide typhoid vaccine instead (see Typhoid fever).

Rotavirus vaccine

Infants with severe combined immunodeficiency (SCID) should not receive rotavirus vaccine. They are unlikely to generate a protective immune response to vaccination and may have an adverse event following the vaccination.

Infants with HIV who are asymptomatic and have an adequate age-specific CD4⁺ count may receive rotavirus vaccine.

Yellow fever vaccine

Yellow fever vaccine is generally contraindicated in travellers who are immunocompromised and going to yellow fever–endemic countries.

However, certain travellers may receive the vaccine on a case-by-case basis after seeking specialist advice and having a risk assessment. This includes certain people with HIV (see Yellow fever). 

People who have had a haematopoietic stem cell transplant after a dose of yellow fever vaccine are recommended to receive an extra vaccine dose if they will be in an area with a risk of yellow fever virus transmission. This is regardless of when they received their last yellow fever vaccine.

Varicella and zoster vaccines

Varicella-containing vaccines are contraindicated in people who are significantly immunocompromised as a result of a medical condition.

Varicella-containing vaccines are contraindicated in people receiving high-dose systemic immunosuppressive therapy such as chemotherapy, radiation therapy or oral corticosteroids. Carefully consider vaccination for people who are taking combinations of immunosuppressive therapies.

People with a current or recent severe immunocompromising condition, from a primary or acquired medical condition or treatment, should not receive live zoster vaccine (Zostavax). They are recommended to receive recombinant zoster vaccine (Shingrix).

People who are anticipating being significantly immunocompromised in the future should seek specialist advice before receiving live zoster vaccine (Zostavax). They are recommended to receive recombinant zoster vaccine (Shingrix).

People ≥50 years of age with mild immunocompromising conditions are recommended to receive recombinant zoster vaccine (Shingrix), but may receive live zoster vaccine (Zostavax) after assessment using the Live zoster vaccine (Zostavax) screening for contraindications tool.

Adults with asymptomatic HIV can receive recombinant zoster (Shingrix), and may receive live zoster vaccine (Zostavax) on a case-by-case basis.

See zoster (herpes zoster).

Inadvertently giving a live vaccine to someone who is immunocompromised

Promptly assess people who are immunocompromised and have been inadvertently given a live vaccine. Establish how severely they are immunocompromised and the level of risk for vaccine-associated adverse effects. This will inform appropriate management.

Management may include quickly giving immunoglobulin, or antiviral or antibacterial therapy, depending on the vaccine and clinical context.

Seek specialist advice and notify state or territory public health authorities.

People who are immunocompromised are routinely recommended to receive:

• influenza vaccine
• pneumococcal vaccine
• meningococcal vaccine
• HPV vaccine
• hepatitis B vaccine
• recombinant zoster vaccine (Shingrix)
• COVID-19 vaccine
• respiratory syncytial virus (RSV) vaccine

Influenza vaccine

All people ≥6 months of age who are immunocompromised are recommended to receive an influenza vaccine every year (see Influenza). 

Every year, new influenza vaccine strains can circulate in the community. Cross-protective immunity to these strains in the population is low. This underpins the need for annual seasonal influenza vaccination in all people, but particularly people who are immunocompromised.

If a major shift in the circulating influenza virus occurs, such as during an influenza pandemic, people who are immunocompromised might benefit from receiving 2 doses of inactivated influenza vaccine, at least 4 weeks apart, for an optimal immune response. This is regardless of their previous influenza vaccination history.

For example, during the 2009–10 H1N1 global influenza pandemic, adolescents and adults who were immunocompromised and who received 2 vaccines doses had better rates of seroconversion.⁶

Information about extra doses in people who are immunocompromised will be provided as necessary in these situations. Updated influenza vaccine recommendations are published every year on the Australian Government Department of Health website and updated in this Handbook. 

There are precautions relating to the use of influenza vaccine in cancer patients who are neutropenic or receiving treatment with checkpoint inhibitors. See People with Cancer and Influenza.

Pneumococcal vaccine

People who are immunocompromised are recommended to receive extra pneumococcal vaccine doses in addition to the doses recommended for healthy people. The timing, number of doses and type of vaccine(s) depend on the person’s age, when the condition was diagnosed, whether they have already received pneumococcal vaccines and whether they are Aboriginal or Torres Strait Islander. See Pneumococcal disease and Catch-up vaccination.

Meningococcal vaccine

Certain people who are immunocompromised (particularly those with asplenia) may need extra doses of meningococcal vaccines. This applies to both MenACWY (quadrivalent meningococcal) and MenB (meningococcal B) vaccines. See Meningococcal disease.

HPV vaccine

People who have certain immunocompromising conditions are recommended to receive HPV (human papillomavirus) vaccine in a 3-dose course, regardless of their age at vaccination. See Human papillomavirus. 

Hepatitis B vaccine

Higher-strength doses, double doses or additional doses of hepatitis B vaccines are recommended for: 

• people receiving renal dialysis
• people who have had a haematopoietic stem cell transplant 
• people with HIV

See Hepatitis B.

Recombinant zoster vaccine (Shingrix)

People aged ≥18 years who are immunocompromised or shortly expected to be immunocompromised are recommended to receive recombinant zoster vaccine (Shingrix) in a 2-dose course. See zoster (herpes zoster).

COVID-19 vaccine

COVID-19 vaccines are inactivated, and safe for use in people with immunocompromise. The risk of severe illness from SARS-CoV-2 is higher in people with immunocompromise, and all immunocompromised people are recommended to receive COVID-19 vaccine. A third primary course is recommended for people with severe immunocompromise, as defined in the ATAGI recommendations on the use of a third primary dose of COVID-19 vaccine in individuals who are severely immunocompromised. Additional booster doses are also recommended for people with immunocompromise based on their age and risk profile, as outlined in the ATAGI clinical guidance for COVID-19 providers.

Respiratory syncytial virus (RSV) vaccine

People aged ≥60 years who have immunocompromising conditions associated with increased risk of severe RSV disease are recommended a single dose of RSV vaccine. See RSV (Table. Conditions associated with increased risk of severe RSV disease in adults).

Household contacts and other close contacts of people who are immunocompromised should be fully vaccinated according to current recommendations. Their vaccination history should be reviewed, and they should receive any necessary catch-up doses. This helps protect people who are immunocompromised, whether they are a child or an adult, by reducing their exposure to disease.

Annual influenza vaccination is recommended for all household contacts (≥6 months of age) of people who are immunocompromised. 

Household contacts of people who are immunocompromised may also need to receive additional vaccine doses, such as pertussis-containing vaccine and/or varicella vaccine (see Pertussis and Varicella).^7-9

Live viral vaccines in household contacts

Vaccinating household contacts can reduce the risk of disease spreading to the person who is immunocompromised. Household contacts of people who are immunocompromised are recommended to be reviewed for their need to receive the following live attenuated viral vaccines: 

• MMR 
• MMRV
• rotavirus
• varicella 
• zoster (household contacts ≥50 years of age [recombinant zoster vaccine [Shingrix] is preferred but Zostvax can be used in those who are immunocompetent])
• mpox vaccine (JYNNEOS)

There is no risk of transmission of the MMR and mpox (JYNNEOS) vaccine viruses, and an almost negligible risk of transmission of varicella-zoster vaccine virus (from varicella or zoster vaccine).

However, there is a small risk of transmission of the rotavirus vaccine virus. This can be minimised by handwashing and careful disposal of soiled nappies.

See also Measles, Rotavirus and Varicella.

People with cancer, particularly generalised malignancy, are likely to be severely immunocompromised as a result of their disease and their treatment (such as chemotherapy or radiotherapy).

Guidelines for vaccination may vary by person, depending on their:

• age
• vaccination history
• disease and treatment
• level of immunocompromise

If a person has not completed a primary vaccination schedule before diagnosis and treatment, it is important to continue to offer routine or catch-up vaccination during their therapy, when possible, according to the principles in this section. Discuss any questions with the person’s treating oncologist and an immunisation specialist.

People with severe neutropenia

People with severe neutropenia (absolute neutrophil count <0.5 × 10⁹ per L) should not receive any vaccines, to avoid an acute febrile episode.

People receiving immune-oncology therapy

People who are receiving cancer immuno-oncology therapies (checkpoint inhibitors) may have a higher risk of adverse events following immunisation with influenza vaccine.^10,11 

Checkpoint inhibitors include:

• CTLA-4 inhibitors (such as ipilimumab)
• PD-1 and PD-L1 inhibitors (such as nivolumab or pembrolizumab)

Live vaccines are not recommended for these patients. Caution is advised with inactivated vaccines, particularly the influenza vaccine. Consult the person’s treating oncologist about the risks and benefits of influenza vaccination in people taking these treatments.

Live vaccines for people with cancer

Live vaccines are contraindicated in cancer patients who are receiving immunosuppressive therapy and/or who have poorly controlled malignant disease. 

Seronegative people, who are at risk of these diseases, are recommended to receive these vaccines at least 3 months after they finish chemotherapy, provided that the underlying malignancy is in remission and they are not severely immunocompromised.¹² 

People who have recently received blood products or immunoglobulins, including people with cancer, should wait to receive live viral vaccines (MMR-containing or varicella-containing vaccines), according to Table. Recommended intervals between immunoglobulins or blood products, and measles-mumps-rubella, measles-mumps-rubella-varicella or varicella vaccination. 

Inactivated vaccines for people with cancer

People receiving chemotherapy may receive inactivated vaccines (such as pneumococcal conjugate vaccines [13vPCV, 15vPCV or 20vPCV] or hepatitis B) according to a routine or catch-up vaccination schedule. The immune response may be suboptimal, but it is safe for the person to receive these vaccines. 

HPV vaccine

If the person needs HPV vaccine, 9vHPV (9-valent HPV) vaccine is recommended in a 3-dose schedule (0, 2, 6 months). This is regardless of the person’s age at the start of vaccination (see Human papillomavirus).

Influenza vaccine

All cancer patients aged ≥6 months are recommended to receive influenza vaccine each year. 

Some people with cancer receive cancer immuno-oncology therapies, such as:

• CTLA-4 inhibitors (such as ipilimumab)
• PD-1 and PD-L1 inhibitors (such as nivolumab or pembrolizumab)

Consult the person’s treating oncologist about the optimal timing of influenza vaccination in people taking these treatments.

Cancer patients who have had a haematopoetic stem cell transplant or solid organ transplant and are receiving influenza vaccine for the 1st time after transplant are recommended to receive 2 vaccine doses at least 4 weeks apart (irrespective of age), and 1 dose each year after that. See Haematopoietic stem cell transplant recipients.

Pneumococcal vaccine

People with underlying haematological and other generalised malignancies are recommended to receive pneumococcal vaccine. This is because they have an increased risk of invasive pneumococcal disease.¹³

Children or adults who are newly diagnosed with cancer are recommended to receive 1 dose of a pneumococcal conjugate vaccine (13vPCV or 15vPCV or 20vPCV) and 2 doses of 23vPPV (23-valent pneumococcal polysaccharide vaccine). Children <5 years of age who are not up to date with age-appropriate doses (in the infant schedule) may need more doses.^14,15-17 See Pneumococcal disease and Catch-up vaccination for details.

Zoster vaccine

All cancer patients who are immunocompromised and aged ≥18 years are recommended to receive 2 doses of recombinant zoster vaccine (Shingrix) 1-2 months apart. See Zoster (herpes zoster).

COVID-19 vaccine

Cancer patients who have severe immunocompromise are recommended to receive a 3rd dose of COVID-19 vaccine. Recommendations for additional booster doses are based on a patient’s degree of immunocompromise, age and presence of other risk factors, and are outlined in the ATAGI clinical guidance for COVID-19 providers.

Respiratory syncytial virus (RSV) vaccine

Cancer patients aged ≥60 years are recommended to receive a single dose of an RSV vaccine.

People who have completed cancer therapy

People who have finished cancer therapy and who completed a primary vaccination schedule before diagnosis can receive most of the following vaccines without having their antibody titres checked beforehand.

If the person is well and in remission for 6 months after therapy, they are recommended to receive the following booster doses after they have completed their primary vaccination schedule:

• DTPa (diphtheria-tetanus-acellular pertussis)–containing and IPV (inactivated poliovirus)–containing vaccines
  Single dose of DTPa-IPV if <10 years of age. Single dose of either dT or reduced antigen content dTpa if ≥10 years of age, and a single dose of IPV.
• MMR-containing vaccine
  Single dose, followed by antibody testing for immunity to measles and rubella at 6–8 weeks after vaccination. People who have not seroconverted are recommended to receive an extra dose. 
• Hepatitis B vaccine
  Single dose.
• Pneumococcal vaccines
  If the full course was not received previously a single dose of a pneumococcal conjugate vaccine (13vPCV or 15vPCV or 20vPCV) and 2 doses of 23vPPV after the conjugate vaccine. See Pneumococcal disease and Catch-up vaccination for details.
• Hib (Haemophilus influenzae type b) vaccine
  Single dose if either <5 years of age or if ≥5 years of age with asplenia. See Table. Recommendations for vaccination in people with functional or anatomical asplenia.
• Meningococcal vaccine
  Single dose of MenACWY. Revaccination with MenACWY is recommended every 5 years for people with asplenia. Single dose of MenB. See Table. Recommendations for vaccination in people with functional or anatomical asplenia.
• 9vHPV vaccine
  If no previous doses received, a single dose is recommended if commencing vaccination before the 26^th birthday and no longer immunocompromised. A 3-dose schedule (0, 2, 6 months) is recommended if commencing vaccination from 26 years of age or if still immunocompromised. See Human papillomavirus.
• Varicella vaccine
  People who are seronegative for varicella-zoster virus should receive a 2-dose schedule of varicella vaccine, at least 6 months after chemotherapy has finished. MMRV vaccine can be used in children aged <14 years. See Varicella.
• Respiratory syncytial virus (RSV) vaccine
  Single dose for people aged ≥60 years.

Depending on the transplanted organ, people who have a solid organ transplant receive variable doses of immunosuppressive agents to prevent rejection. This may influence the effectiveness and safety of vaccines. 

Where possible, children and adults having a solid organ transplant should receive all routine scheduled or catch-up vaccines well before transplantation. It is important to administer all necessary live vaccines at least 1 month before solid organ transplantation, where possible.

Live vaccines are contraindicated in most post-transplantation protocols because of concerns about disseminated infection. However, data for transplant recipients are limited.^18-20 

Inactivated vaccines can be safely given after transplantation, but it is usually best to receive them at least 6 months after transplantation to maximise the immune response.^18,21 

See Table. Recommended vaccines for people before and after a solid organ transplant for the recommended vaccines for child and adult solid organ transplant recipients.

Any transplant recipient who anticipates travelling may need additional vaccination, such as for hepatitis A and typhoid (see Vaccination for international travellers).

Protective immunity to vaccine-preventable diseases is partially or completely lost after an allogeneic or autologous haematopoietic stem cell transplant (HSCT).

Haematopoietic stem cells can be sourced from either the intended recipient (autologous) or a donor (allogeneic). The sites from which haematopoietic stem cells are taken are:

• peripheral blood, or
• bone marrow, or
• umbilical cord blood

People become immunocompromised after HSCT as a result of a combination of:

• the preparative chemotherapy given before transplantation (allogeneic or autologous HSCT)
• graft-versus-host disease (GVHD) (allogeneic HSCT)
• immunosuppressive therapy after transplantation (usually only allogeneic HSCT)

Autologous HSCT recipients often have impaired immunity due to high-dose chemotherapy and radiotherapy. GVHD is not a concern because the transplant recipient supplies the donor stem cells. In most cases, autologous HSCT recipients recover their immunity more quickly than allogeneic HSCT recipients.

Persisting immunocompromise is common, particularly in people with chronic GVHD after allogeneic HSCT. Chronic GVHD is associated with functional hyposplenism and, therefore, increased susceptibility to infections with encapsulated organisms, especially Streptococcus pneumoniae. People with chronic GVHD who remain on immunosuppressive medicine are also recommended to receive antibiotic prophylaxis.²⁴

Published guidelines do not support separate vaccination schedules for autologous or allogeneic HSCT recipients because of limited data. The same vaccination schedule is recommended for both groups, regardless of the donor source (peripheral blood, bone marrow or umbilical cord) or preparative chemotherapy (ablative or reduced intensity).^24,25 However, recommendations for receiving live vaccines may vary according to the person’s level of immunocompromise after HSCT.

The schedule is shown in Table. Recommendations for revaccination after haematopoietic stem cell transplant in children and adults.

Live vaccines in HSCT recipients

Do not give live vaccines to HSCT recipients until 24 months after the transplant, and provided that the person has no ongoing immunosuppression. See Table. Recommendations for revaccination after haematopoietic stem cell transplant in children and adults. 

Do not give live vaccines to HSCT recipients with ongoing GVHD or who remain on immunosuppressive therapy, regardless of the time since HSCT.

Inactivated vaccines in HSCT recipients

HSCT recipients usually have a poor immune response to inactivated vaccines during the first 6 months after HSCT. 

Haematopoietic stem cells from donors who receive hepatitis B, tetanus, Hib and pneumococcal conjugate vaccines before stem cell harvesting can improve early antibody responses in HSCT recipients who receive vaccines during the post-transplantation period.^26-29 However, practical and ethical considerations can limit the use of donor immunisation.

Serological testing in HSCT recipients

Vaccines for which serological testing is not recommended

Routine serological testing for several vaccine-preventable diseases and the antibody levels that confer protective immunity against disease are poorly defined in some cases. See Laboratory testing to guide catch-up vaccination in Catch-up vaccination.

Serological testing is not recommended before or after giving the following vaccines to HSCT recipients: 

• diphtheria
• Hib
• influenza
• pneumococcal 
• poliomyelitis
• tetanus
• varicella (post-vaccination serology not recommended)
• COVID-19
• respiratory syncytial virus (RSV)

Post-vaccination varicella serology using commercial assays is very insensitive for vaccine-induced immunity compared with natural infection. It is not recommended after HSCT (see Varicella). 

Vaccines for which serological testing is recommended

Serological testing is recommended after vaccination in HSCT recipients:

• around 4–6 weeks after vaccination with the final dose of a hepatitis B vaccine course
• around 4–6 weeks after vaccination with the 2nd dose of MMR vaccine 

This is because antibody levels will determine the need for revaccination.²⁵

A recommended schedule of vaccination is outlined in Table. Recommendations for revaccination after haematopoietic stem cell transplant in children and adults.

Any transplant recipient who anticipates travelling may need additional vaccination, such as for hepatitis A and typhoid (see Vaccination for international travellers).

People with HIV should have vaccination schedules based on their:³⁷

• age
• CD4⁺ count (which indicates how immunocompromised they are)
• risk of infection
• concurrent medical conditions or medications (which may be immunocompromising)

To determine the person’s level of immunocompromise, see Table. Levels of immunocompromise in children and adults with HIV.

Children who acquired HIV around the time of their birth are substantially different from adults with HIV. Young children’s immunisation and first exposure to vaccine antigens occur after HIV is acquired. In adults with HIV, most vaccines induce a secondary (boosted) immune response that builds on a previous immune response. 

People with HIV of any age whose disease is well controlled are likely to respond well to vaccines. HIV is usually well controlled when:

• the person is on combination antiretroviral therapy 
• they have an undetectable or low viral load 
• they have a good CD4⁺ lymphocyte count

Live attenuated vaccine considerations for people with HIV

Live attenuated vaccines include:

• BCG vaccine
• live oral cholera vaccine (Vaxchora)
• Japanese encephalitis vaccine
• MMR vaccine
• Mpox vaccine (JYNNEOS)
• rotavirus vaccine
• oral typhoid vaccine
• varicella vaccine
• yellow fever vaccine
• live zoster vaccine (Zostavax)

BCG vaccine

Children or adults with HIV should not receive BCG vaccine, because of the risk of disseminated BCG infection.^39,40 See also Tuberculosis.

Live cholera vaccine (Vaxchora)

People with HIV should not receive oral live attenuated cholera vaccine. Use the inactivated oral cholera vaccine instead (see Cholera).

Japanese encephalitis vaccine

People with HIV who need Japanese encephalitis vaccine should not receive the live attenuated recombinant vaccine (Imojev). Use the inactivated vaccine (JEspect) instead (see Japanese encephalitis). 

MMR vaccine

Children with HIV should receive MMR vaccine in a 2-dose schedule at 12 months and 18 months of age, unless the child has a CD4⁺ count of <750 per µL.^41-43

Children with HIV are likely to have a better serological response after the 2nd dose of MMR vaccine.^44,45 They can receive the 2nd dose soon after the 1st dose (with a minimum interval between doses of 4 weeks) to increase the likelihood of a serologic response to all 3 vaccine components. This is particularly recommended if the child is travelling overseas or if there is a local measles outbreak.

Measles may cause severe disease in children with HIV, particularly those with a CD4⁺ count of <750 per µL, who may have reduced protection from vaccination. Children with HIV should receive normal human immunoglobulin as post-exposure prophylaxis after being exposed to measles, regardless of vaccination status (see Measles).⁴⁶

Asymptomatic adults with HIV should receive 1 or 2 doses of MMR vaccine if they have a CD4⁺ count ≥200 per µL and are seronegative for any of the vaccine components. The number of doses depends on the number of previous doses and whether they seroconvert. MMR vaccine does not have a significant effect on the CD4⁺ count or viral load of adults with HIV.⁴⁷

People with HIV are not recommended to receive the combination MMRV vaccine. There are no data on MMRV vaccine in people with HIV (see Varicella).

Mpox vaccine

People living with HIV can receive replication-deficient live attenuated mpox vaccine, MVA-BN (JYNNEOS), although the immune response may be reduced. Specialist medical advice on other measures may be required and additional doses should be considered for those at ongoing risk of exposure (See also Mpox).

Rotavirus vaccine

Infants with HIV who are asymptomatic can receive rotavirus vaccine according to the routine age-based schedule.

Rotavirus vaccines seem to be safe and immunogenic in infants with HIV, but data are limited.^48,49

Infants with HIV who are severely immunocompromised should not receive rotavirus vaccine (see also Rotavirus).

Typhoid vaccine

People with HIV should not receive oral live attenuated typhoid vaccine. Use the inactivated parenteral Vi polysaccharide typhoid vaccine instead (see Typhoid fever). 

Varicella vaccine

Asymptomatic adults and children ≥12 months old with HIV may receive the varicella vaccine. 

Data on efficacy and safety in people with HIV are limited.^50-52

Children ≥12 months of age with an age-specific CD4⁺ count of ≥15% of total lymphocytes are recommended to receive 2 doses of monovalent varicella vaccine at least 3 months apart.^53,54

Adults with HIV who are varicella seronegative and have a CD4⁺ count of ≥200 per µL are recommended to receive 2 doses of monovalent varicella vaccine at least 3 months apart.⁵⁴

People with HIV are not recommended to receive the combination MMRV vaccine. There are no data on MMRV in people with HIV (see Varicella).

Yellow fever vaccine

People with HIV who are not immunocompromised (CD4⁺ count of >200 per µL) can receive yellow fever vaccine if they are at risk of infection. People with HIV should only receive yellow fever vaccine if potential exposure to yellow fever virus is unavoidable.

Also seek advice from the treating physician.⁵⁵ (See also Yellow fever and Vaccination for international travellers).

Live zoster vaccine (Zostavax)

Adults with symptomatic HIV infection are not recommended to receive Zostavax.

People aged ≥50 years with asymptomatic HIV infection can receive Zostavax, if recombinant zoster vaccine (Shingrix) is not accessible, and if they; are on antiretroviral therapy, have a very low or undetectable viral load, and have a CD4⁺ count of ≥350 per µL.

If there is a strong indication to vaccinate, some experts suggest that adults with a CD4⁺ count of >200 per µL can safely receive Zostavax.⁵⁶ Seek expert advice from the treating physician or an immunisation specialist. Confirm previous infection with varicella-zoster virus using serological testing and see Live zoster vaccine (Zostavax) screening for contraindications tool before vaccination. 

Zostavax is only registered for use in adults ≥50 years of age. (See also Zoster [herpes zoster]).

Inactivated vaccines for people with HIV

Inactivated vaccines include:

• meningococcal vaccines
• HPV vaccine 
• DTPa/dTpa, Hib and IPV vaccines
• hepatitis A vaccine
• hepatitis B vaccine
• influenza vaccine
• pneumococcal vaccine
• Q fever vaccine
• parenteral typhoid vaccine, Japanese encephalitis vaccine and rabies vaccines 
• Recombinant zoster vaccine (Shingrix)
• COVID-19 vaccine
• respiratory syncytial virus (RSV)

Meningococcal vaccines

People with HIV are recommended to receive MenACWY and MenB vaccines (see Meningococcal disease). 

People with HIV may have a diminished immune response after a single dose of MenACWY.^57-59 However, this improves for some serogroups after a 2nd dose.^58-61

There are no clinical data on the use of MenB vaccine in people with HIV. Vaccination is recommended based on the expected benefit in these people.

HPV vaccine

Children (≥9 years of age) and adults with HIV can receive 9vHPV vaccine. HPV vaccines are safe and immunogenic in people with HIV.^62-64 

People with HIV are recommended to receive a 3-dose course of 9vHPV vaccine at 0, 2 and 6 months regardless of their age when they started vaccination.

Males aged 27–45 years who receive HPV vaccine are unlikely to have different immunogenicity or adverse events compared with females in this age group, for whom the vaccine is currently registered. However, these men may have less benefit if they have already been infected with HPV. HPV vaccine provides the most benefit when given to children or young adolescents before sexual debut (see Human papillomavirus). 

Assess the need for, and potential benefits of, vaccination in older adults before HPV vaccination (see Human papillomavirus). Discuss with the treating specialist and an immunisation expert, if required.

DTPa/dTpa, Hib and IPV vaccines

People with HIV can receive DTPa or dTpa, Hib and IPV vaccines according to routine recommendations^37,65 (see Diphtheria, Tetanus, Pertussis, Haemophilus influenzae type b and Poliomyelitis).

Hepatitis A vaccine

Hepatitis A vaccines are immunogenic in most children with HIV.⁶⁶ Hepatitis A vaccine is only recommended for use in non-immune people with HIV if they have independent risk factors for acquiring hepatitis A (see Hepatitis A).

Hepatitis B vaccine

People with HIV can safely receive hepatitis B vaccine. Because of immune suppression, they may have a diminished immunological response. Check for previous hepatitis B infection using serological testing before vaccination.

Limited studies in HIV1-positive adults show an improved and accelerated serological response to a vaccination schedule that comprises 4 double doses. This means 2 injections of the standard adult dose (using Engerix-B) on each occasion, at 0, 1, 2 and 6 months.^67,68 

Children with HIV are recommended to receive 3 doses of hepatitis B vaccine using an adult formulation. This is double the standard recommended dose for children.^53,54 

Measure the antibody levels when the vaccination schedule is finished (1 month after the final vaccine dose). If the titre of antibody to hepatitis B surface antigen is <10 mIU per mL, give extra doses (see Hepatitis B). 

Influenza vaccine

All adults and children (≥6 months of age) with HIV are recommended to receive influenza vaccine every year. 

All children with HIV <9 years of age are recommended to receive 2 doses at least 4 weeks apart the 1st time they receive influenza vaccine. HIV viral load may increase after influenza vaccination, but the vaccine does not affect CD4⁺ counts, and the benefits exceed the risk.^69-72 (See also Influenza).

Pneumococcal vaccine

Respiratory and invasive pneumococcal disease are frequent causes of morbidity in children and adults with HIV (see List. Risk conditions for pneumococcal disease in Pneumococcal disease).⁷³ 

Children with HIV are recommended to receive a pneumococcal conjugate vaccine (13vPCV, 15vPCV or 20vPCV) and 23vPPV. The number of doses depends on age at diagnosis and vaccination history — see Table. Catch-up schedule for pneumococcal conjugate vaccines for Aboriginal and Torres Strait Islander children living in NT, Qld, SA or WA ONLY, and all children with risk condition(s) for pneumococcal disease, aged <5 years.

Children aged >12 months and adults who are newly diagnosed with HIV are recommended to receive a single dose of a pneumococcal conjugate vaccine (PCV) (13vPCV, 15vPCV or 20vPCV), followed by 2 doses of 23vPPV. If they have previously received doses of 23vPPV, they are recommended to receive the dose of  the pneumococcal conjugate vaccine 12 months after their last 23vPPV dose. If they have already received at least 2 doses of 23vPPV, no further 23vPPV doses are recommended. See Pneumococcal disease for age-specific recommendations.

Q fever vaccine

There are no data on Q fever vaccine in people with HIV. Q fever vaccine is contraindicated in people who are immunocompromised.

Typhoid, Cholera, Japanese encephalitis and rabies vaccines

People with HIV can safely receive the following vaccines if they are travelling or living in an at-risk area:

• parenteral Vi polysaccharide typhoid vaccine
• inactivated oral cholera vaccine (Dukoral)
• inactivated Japanese encephalitis vaccine (JEspect)
• rabies vaccine

Recombinant zoster vaccine (Shingrix)

People aged ≥18 with HIV can safely receive recombinant zoster vaccine (Shingrix), and this is the preferred zoster vaccine for this population. See Zoster (herpes zoster).

COVID-19 vaccine

People with HIV who have CD4 counts <250/µL, or those with a higher CD4 count unable to be established on effective antiretroviral therapy (ART) are recommended to receive a 3rd primary dose of COVID-19 vaccine. A 3rd primary dose is not required for people receiving ART who have CD4 counts ≥ 250/µL. Additional doses may be required based on age, degree of ongoing immunosuppression and presence of other risk factors for severe illness.

Respiratory syncytial virus (RSV) vaccine

People aged ≥60 years with HIV are recommended a single dose of RSV vaccine.

People with an absent or dysfunctional spleen are at a lifelong increased risk of fulminant bacterial infection, especially invasive pneumococcal disease (IPD).^13,74 In addition to being up to date with all routinely recommended vaccines, people with functional or anatomical asplenia are recommended to receive:

• Hib vaccine
• influenza vaccine
• meningococcal vaccine
• pneumococcal vaccine
• Respiratory syncytial virus (RSV) vaccine

Give the vaccines according to the person’s age and immunisation history, and review their immunisation status regularly.⁷⁵

Specific vaccine recommendations for people with asplenia are shown in Table. Recommendations for vaccination in people with functional or anatomical asplenia.

People having an elective splenectomy are recommended to receive all extra vaccine doses by 2 weeks before the scheduled operation date, if possible.

People having an unplanned splenectomy are recommended to start receiving extra vaccine doses from about 1 week after the splenectomy.⁷⁶

Children with asplenia are also recommended to receive antibiotic prophylaxis to prevent bacterial infection, until they are at least 5 years of age.^77,78 

Vaccination cannot protect against all bacterial infections, or even all pneumococcal serotypes that cause IPD. This makes it important that people with asplenia know about the lifelong increased risk of severe bacterial infection, even if they have received all appropriate vaccinations.

Educate all people with asplenia, and their parents and carers, about the importance of recognising and treating febrile illnesses early. This includes using emergency antibiotics. Asplenic people are recommended to wear a medical alert.

Hib vaccine

People with asplenia are recommended to receive a single dose of Hib vaccine if they:

• were not vaccinated in infancy, or 
• are incompletely vaccinated 

See Haemophilus influenzae type b and Table. Catch-up schedule for Haemophilus influenzae type b (Hib) vaccination for children <5 years of age in Catch-up vaccination. 

People with asplenia do not need extra booster doses of Hib vaccine. 

People who have received all scheduled doses of Hib vaccine do not need a booster dose before or after splenectomy.⁷⁹ 

Influenza vaccine

All people, especially those who are immunocompromised, are recommended to receive influenza vaccine every year (see Influenza). 

Secondary bacterial infections, such as IPD, can complicate influenza infection. 

The influenza vaccine dose depends on the person’s previous influenza vaccination history and age. See also Table. Recommended doses of influenza vaccine by age group in Influenza.

Meningococcal vaccine

People with asplenia are recommended to receive MenACWY and MenB vaccines from 2 months of age. The vaccine brand and doses required depend on the person’s age when they start the vaccine course. See Table. Recommendations for MenACWY vaccine for people with a specified medical condition that increases their risk of invasive meningococcal disease and Table. Recommendations for MenB vaccine for people with a specified medical condition that increases their risk of invasive meningococcal disease in Meningococcal disease.

Pneumococcal vaccine

People with asplenia are recommended to receive extra doses of pneumococcal vaccine, depending on their age and previous vaccination history (see Table. Recommendations for vaccination in people with functional or anatomical asplenia). See Pneumococcal disease and Table. Catch-up schedule for pneumococcal conjugate vaccines for Aboriginal and Torres Strait Islander children living in NT, Qld, SA or WA ONLY, and all children with risk condition(s) for pneumococcal disease, aged <5 years in Catch-up vaccination for more details.

Older children and adults with asplenia who have never received any pneumococcal conjugate vaccine (PCV)  are recommended to receive a single dose of a pneumococcal conjugate vaccine (13vPCV or 15vPCV or 20vPCV).⁸⁰ This should precede 23vPPV doses, when possible. However, if they have already received 1 or more doses of 23vPPV, they should receive the pneumococcal conjugate vaccine at the next available opportunity, and at least 12 months after the last 23vPPV dose. A 2nd dose of 23vPPV is recommended 12 months after the pneumococcal conjugate vaccine dose, or 5 years after the previous 23vPPV dose, whichever is later. Pneumococcal disease outlines the age-specific recommendations.

Respiratory syncytial virus (RSV) vaccine

A single dose of RSV vaccine is recommended in adults aged ≥60 years who are at increased risk of severe RSV disease including those with asplenia or splenic dysfunction.

People with autoimmune conditions are at higher risk of vaccine-preventable diseases, and associated morbidity and mortality. Examples of these conditions are:

• systemic lupus erythematosus
• rheumatoid arthritis
• inflammatory bowel disease
• multiple sclerosis

These people are also at risk of infection as a result of treatment with immunosuppressive agents such as corticosteroids and DMARDs (disease-modifying anti-rheumatic drugs).⁸¹ DMARDs encompass a range of anti-inflammatory and immunosuppressing agents. The resulting level and nature of immunocompromise in each person depends on:

• the specific agent(s) used
• the mechanism of action
• the dosage
• whether the treatment is combined with other therapies, such as corticosteroids (see People receiving corticosteroid therapy)

People with autoimmune diseases and other chronic conditions are recommended to receive inactivated vaccines to optimise protection against disease. There is potential for reduced immunogenicity of vaccines in these people due to both immunosuppressive treatment and the underlying disease.^82-84 Extra vaccine doses, such as for pneumococcal vaccine, may be needed.

However, clinical and laboratory measures of disease activity, and the choice, duration and dose of immunosuppressive therapy, do not always predict who will respond poorly to vaccination.^83,85,86

When should people on immunosuppressive therapy receive vaccines

Live vaccines are generally contraindicated in people who are receiving immunosuppressive therapy, such as DMARDs and high-dose corticosteroids. See Use of specific live vaccines in people who are immunocompromised.

However, certain people on DMARDS may receive live vaccines in consultation with a specialist, and with careful consideration of their immune function and current and future disease risk.⁸⁷ For example, people on low-dose conventional synthetic DMARDs (csDMARDs) may receive zoster vaccine (see Herpes zoster).

People should receive all indicated live vaccines at least 1 month before starting immunosuppressive therapy, if possible.

In general, people who are immunocompromised and receiving biological DMARDs (bDMARDs) or targeted synthetic DMARDs (tsDMARDs) should not receive live vaccines until at least 12 months after therapy has ended. However, seek specialist advice about the most appropriate interval for the person and their individual circumstances.

Infants born to mothers who received bDMARDs during pregnancy

Infants aged <6 months who were born to mothers who received bDMARDs, particularly in the 3rd trimester, are not recommended to receive live vaccines, particularly BCG vaccine.^1,88,89 See also Pregnant women and Use of immunosuppressive therapy during pregnancy in Vaccination for women who are planning pregnancy, pregnant or breastfeeding.

There are no data on the use of other live vaccines in infants born to women who have received immunosuppressive therapy during pregnancy. Theoretically, there is a risk in giving rotavirus vaccines to these infants. Some experts recommend not giving rotavirus vaccine to infants born to mothers who received bDMARDs during pregnancy,⁹⁰ particularly in the 3rd trimester. See also Live attenuated vaccines and immunosuppressive therapy in Vaccination for women who are planning pregnancy, pregnant or breastfeeding.

Infants should receive inactivated vaccines according to the recommended schedule. However, immune responses may be suboptimal. These infants may need extra inactivated vaccine doses — seek expert advice from the treating specialist and an immunisation expert.

Association between vaccines and autoimmune conditions, such as Guillain–Barré syndrome

Overall, theoretical concerns that vaccines exacerbate or cause autoimmune diseases such as rheumatoid arthritis, type 1 diabetes and multiple sclerosis have not been substantiated. Large epidemiological studies have not verified these sporadic case reports.^91-94

In almost all cases, people with autoimmune disease can safely receive inactivated vaccines.

In 1976, a small increased risk of Guillain–Barré syndrome (GBS) in the 6 weeks after vaccination was associated with a type of influenza vaccine in the United States. Since then, close surveillance has shown that GBS has occurred at a very low rate of up to 1 per 1 million doses of influenza vaccine, if at all.⁹⁵

People with a history of GBS whose first episode was not after influenza vaccination have an extremely low risk of recurrence of GBS after vaccination.^96-98 Influenza vaccination is recommended for these people.

Influenza vaccination is generally not recommended for people with a history of GBS whose first episode occurred within 6 weeks of receiving an influenza vaccine. There is limited data on the risk of recurrence of GBS in people where the first episode occurred within 6 weeks of influenza vaccination (i.e. the first episode was possibly triggered by the vaccine). In these people, discuss the potential for recurrence if vaccinated, the potential for exacerbation following influenza infection, and other protective strategies (e.g. vaccination of household members). Vaccination can be considered in special circumstances, such as when an alternative cause for GBS, such as Campylobacter jejuni infection, was found or the risk of influenza disease is considered high.

Many well-conducted studies have shown no increased risk of GBS after HPV vaccine.⁹⁹ One smaller study suggested a possible very small increased risk, but this study had a number of limitations.⁹⁹ There is ongoing research to monitor whether there is any increased risk of GBS after HPV vaccine.

One study has suggested a very rare risk of GBS following zoster vaccine, Shingrix.¹⁰⁰ However, GBS may also be triggered by zoster itself,¹⁰¹ and modelling suggests that the overall benefits of vaccination outweigh the risks of GBS.¹⁰²

Narcolepsy (sudden sleeping illness) was associated with AS03-adjuvanted pandemic influenza vaccines in 2009–10. This was mainly seen in the Scandinavian population, and affected children especially.^103-105 These vaccines were not used, and are not available, in Australia.

Discuss individual concerns with, and seek expert advice from, the person’s treating physician or an immunisation specialist.

Hypopituitarism

Hypopituitarism is not a contraindication to vaccination if the person is only receiving physiological corticosteroid replacement for their condition. This is because physiological doses of corticosteroids are not considered immunosuppressive.

If the person has been unwell and is on high-dose corticosteroids for more than 14 days, do not give live vaccines for at least 1 month after stopping therapy. See Table. Recommended timing of live vaccine doses in adults and children taking corticosteroids.

Metabolic diseases

People with metabolic diseases should receive vaccines using the routine schedule. Vaccination is generally considered safe in these people.¹⁰⁶

Influenza and pneumococcal vaccines are recommended for people with chronic medical conditions, such as metabolic disease.

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