Vaccination for international travellers

Millions of Australians travel overseas every year. More than half of these trips are to destinations other than New Zealand, North America and Europe.¹

This page helps with making decisions about travel vaccines. Also check the disease-specific chapters in this Handbook for details about specific vaccines.

See also Infographic. Vaccination for international travellers.

Health risks associated with international travel include exposure to:

• infective agents
• altitude and temperature extremes
• other physical, psychological and environmental hazards
• poor-quality or limited access to clean water, shelter, hygiene and sanitation facilities, and health and medical care

The level of health risks depends on factors such as:

• the traveller’s underlying health and physiological state
• the itinerary and activities undertaken
• the duration of exposure to various hazards during travel

Travellers at increased risk of serious travel-associated infections include:

• young children and infants
• pregnant women
• people with underlying medical conditions, especially immunocompromising conditions due to disease or medical treatment
• people spending extended periods in multiple regions with poor resources or in remote areas
• people participating in events where large numbers of people will gather, such as major sporting, cultural, social or religious events
• migrant families travelling back to their region of origin to visit friends and relatives

Those travelling to visit friends and relatives are more likely to:²

• have closer contact with local populations
• stay in remote or rural areas
• consume higher-risk food and beverages

Those travelling to visit friends and relatives are less likely to:^2,3

• recognise the health risks associated with travelling
• seek pre-travel health advice
• obtain the recommended vaccines or prophylaxis

Exposure to infectious diseases is one of the many health hazards of international travel. Some of these diseases are vaccine preventable. Although some of these diseases are present in Australia, the risk of acquiring them overseas may be higher because of:

• higher disease incidence in other countries
• increased risk of exposure from participating in certain activities while travelling

Foodborne and waterborne infections

It is common for travellers to ingest contaminated food or beverages, resulting in an infection.^4,5 Most infections are diarrhoeal diseases due to enteric pathogens, but some are due to extra-intestinal microorganisms, such as hepatitis A virus and Salmonella enterica serotype Typhi (causing typhoid).

Vaccines are available against hepatitis A, typhoid and cholera.

Vector-borne infections

Insect-borne — especially mosquito-borne — infections, such as malaria and dengue, are important causes of fever in Australian travellers returning from endemic areas, particularly Southeast Asia and Oceania.^5,6

A dengue vaccine (Dengvaxia) is available for the prevention of secondary dengue infections (not primary prevention of initial dengue infection) in select individuals. See Clinical advice: ATAGI statement on use of Dengvaxia® for Australians.

Japanese encephalitis occurs throughout much of Asia and the Western Pacific region, including eastern Indonesia and Papua New Guinea.⁷ Yellow fever occurs only in parts of Africa and South America,⁸ and tick-borne encephalitis occurs in parts of Europe and Asia.⁹

Vaccines are available against Japanese encephalitis, yellow fever and tick-borne encephalitis.

Some other vector-borne diseases and parasitic (including protozoal and helminthic) diseases are also important for international travellers. Some are preventable through appropriate barrier precautions and chemoprophylaxis (for example, malaria).⁹

Aerosol-borne infections

Vaccine-preventable infections transmitted by aerosols and/or droplets include:⁹

• influenza (the most common vaccine-preventable infection among travellers)¹⁰
• meningococcal disease
• measles
• mumps
• varicella (chickenpox)

The incidence of measles and mumps is higher in many overseas countries, including some developed countries, than in Australia.

Tuberculosis is a rare infection in travellers. Expatriates who live in endemic areas for a long time are more likely to acquire tuberculosis than short-term visitors.¹¹

Vaccines are available against all of these diseases.

Bloodborne infections

Some Australian travellers may be at risk from bloodborne and sexually transmissible infections, such as hepatitis B, hepatitis C and HIV. In some areas, healthcare workers using non-sterile medical equipment or other poor infection control practices may transmit these viruses and other bloodborne agents.

Vaccines are available against hepatitis B.

Exotic infectious agents

Travellers may be exposed to a variety of other exotic infections, such as:

• rabies from bites or scratches from rabid dogs and other mammals in many countries
• schistosomiasis from exposure to water infested with the parasites, especially in Africa
• leptospirosis through activities such as rafting or wading in contaminated streams

Of these diseases, vaccines are available only against rabies.

Although recommending appropriate vaccines is important, it is not the only part of a pre-travel medical consultation. Travel vaccines — those relevant for travelling — include all relevant vaccines, not just the ones that prevent diseases that most commonly occur overseas.

Do not recommend a vaccine based only on the destination country, because there is no single ‘correct’ list of vaccines for travel to any particular country.

There are 3 categories of travel vaccines:

• routinely recommended vaccines (not specific to travelling overseas)
• selected vaccines based on travel itinerary, activities and likely risk of disease exposure
• vaccines required by the International Health Regulations 2005 (IHR) or for entry into specific countries

Questions for a pre-travel medical consultation

During a pre-travel medical consultation, ask questions about the traveller’s:

• personal information, including age, whether they are pregnant or planning pregnancy, and possible financial constraints
• underlying medical conditions, particularly immunocompromising conditions, and current medicines
• vaccination history (including adverse events following immunisation) and allergy history
• purpose of travel and intended activities, especially those associated with various environmental risks and hazards
• plans for travel insurance

Also ask about their itinerary in detail, including:

• date of departure and time available for vaccinations
• specific localities and routes
• rural versus urban stay
• duration of stay
• likely access to health care and other services
• likelihood of changing the planned itinerary

This information helps to tailor recommendations about preventive vaccination or chemoprophylaxis for exposure risks during the proposed trip. It also allows the clinician to advise about other appropriate preventive health measures (for example, food and water precautions, avoiding bites from mosquitoes or other arthropods) and about managing possible health conditions during travel.

Organisational requirements for vaccination

Some overseas organisations, such as schools, colleges and universities, require evidence of vaccination or immunity against some vaccine-preventable diseases, such as measles and meningococcal disease. Consider these requirements when planning and scheduling vaccines before departure.

Vaccinate all prospective travellers according to the recommended vaccination schedule appropriate for their age, underlying health conditions, occupation and lifestyle. Vaccines might include, for example, pneumococcal polysaccharide vaccine for an older person, or hepatitis B vaccine for a first aid officer. 

Also ensure that all children are vaccinated according to the National Immunisation Program schedule. In exceptional circumstances, give the National Immunisation Program vaccines at the minimum age rather than the recommended age (see Table. Minimum acceptable age for the 1st dose of scheduled vaccines in infants in special circumstances). Children vaccinated using the minimum age rather than the recommended age may need extra vaccine doses to ensure adequate protection. Observe the minimum interval requirements between doses (see Table. Minimum acceptable dose intervals for children <10 years of age). The chances of being exposed to some diseases, such as measles and mumps, may be greater during overseas travel, even to other developed countries.

For some itineraries, it may be appropriate for the traveller to receive some booster doses earlier than the routine recommended time. An example may be diphtheria-tetanus booster.

Diphtheria, tetanus and pertussis

Vaccinate adult travellers against tetanus before departure, particularly if:

• their risk of sustaining a tetanus-prone wound is high
• there could be delays in accessing health services where they can receive tetanus toxoid boosters safely, if required

Adults are recommended to receive a booster dose of tetanus-containing vaccine if their last dose was more than 10 years ago, or if they have never received a dose of dTpa (diphtheria-tetanus-acellular pertussis) vaccine.

Offer dTpa vaccine during a pre-travel consultation if the traveller has never received a dose of dTpa. This provides protection against pertussis (see Pertussis). 

For high-risk travel, consider giving a booster dose of either dTpa or dT vaccine if more than 5 years have passed (see Tetanus).

Hepatitis B

Most Australian children born since 2000 have been vaccinated against hepatitis B under the National Immunisation Program or state and territory school-based vaccination programs.

Hepatitis B vaccine is recommended for long-term or frequent travellers to regions of intermediate or high endemicity of hepatitis B, including:

• Central and South America
• Africa
• Asia
• Oceania

This is because travellers may be exposed to hepatitis B virus through bloodborne routes (including during emergency medical or dental procedures) or sexual routes. According to 1 survey, about half of Australian travellers who spent at least 3 nights in Southeast or East Asia participated in at least 1 activity that had a risk of hepatitis B transmission.¹²

See also Hepatitis B.

Influenza and pneumococcal disease

Older travellers and those with any relevant underlying medical or behavioural risk factors should receive pneumococcal vaccine. See Pneumococcal disease for more details.

Consider influenza vaccine for all travellers, especially if they are travelling to a region during its influenza season. Influenza vaccine is particularly relevant if:

• there is an influenza epidemic at the traveller’s destination
• the person is travelling in a large tourist group, especially one that includes older people
• the person is travelling on cruises, where people are relatively confined for days to weeks

See also Influenza. 

Measles, mumps and rubella

Inadequately vaccinated young adult travellers are responsible for most current measles outbreaks in Australia. This occurs when they acquire the infection overseas and bring it back to Australia. Some countries, regions or communities — including developed countries — have a higher incidence of measles and mumps than Australia.⁹

Review vaccination records for all adolescents and young adults to ensure that they have received 2 doses of measles-containing vaccine. See Epidemiology in Measles.

Australians born during or since 1966 who have not received 2 doses of MMR (measles-mumps-rubella)–containing vaccines are recommended to receive MMR vaccine before travelling. The exception is for pregnant women, because MMR is a live vaccine and is contraindicated in pregnancy. 

People born before 1966 do not need to receive measles-containing vaccine (unless serological evidence indicates that they are not immune). This is because circulating measles virus and disease were prevalent before 1966, so most people would have acquired immunity from natural infection.

However, confirmed cases of measles have occurred in people born before 1966.³ If in doubt about a person’s immunity, it may be faster and easier to vaccinate the person than conduct serological testing. See Serological testing for immunity to measles. 

See also Measles. 

Varicella

Unvaccinated travellers are recommended to receive varicella vaccine if they either:

• have not had clinical disease, or
• have an uncertain history of clinical disease and serology shows a lack of immunity 

See also Varicella.

Meningococcal disease

Vaccination against meningococcal serogroups A, C, W-135, Y and B is recommended for certain age and population groups who are at increased risk of meningococcal disease.

In addition, MenACWY (quadrivalent meningococcal) vaccine is recommended for people who are:

• planning travel to, or living in, parts of the world where epidemics of serogroup A, C, W-135 or Y meningococcal disease occur, particularly the ‘meningitis belt’ of sub-Saharan Africa¹³
• planning travel to mass gatherings, such as pilgrims travelling to the Hajj in Saudi Arabia

Seek up-to-date epidemiological information to determine whether a traveller needs meningococcal vaccination. See Accessing up-to-date travel information.

The Saudi Arabian authorities require that all pilgrims travelling to Mecca (for the Hajj or Umra) have evidence of recent vaccination with the quadrivalent meningococcal vaccine.¹⁴ See Requirements for travellers to Mecca and Accessing up-to-date travel information.

See also Meningococcal disease.

Poliomyelitis

Ensure that all travellers are age-appropriately vaccinated against polio (see Poliomyelitis).

If the person is travelling to a country where wild poliovirus is still circulating, they should receive inactivated poliovirus (IPV) vaccine if they have not completed a 3-dose primary course of any polio vaccine. Travellers who have completed the primary course should receive a single booster dose.

The World Health Organization (WHO) Global Polio Eradication Initiative website website has an up-to-date list of polio-affected countries.

Documented evidence of polio vaccination is not routinely required for travellers under the International Health Regulations. However, documented evidence of vaccination may be temporarily required according to WHO recommendations in response to new evidence of the spread of wild poliovirus (see Vaccines required by the International Health Regulations or for entry into specific countries and Documentation and certificates).

International polio epidemiology and associated travel requirements can change. Check the Australian Government Department of Health website for current recommendations for Australian travellers.

Use a risk assessment approach when recommending travel vaccines. Weigh the potential risks of disease exposure and protective benefits from vaccination against potential adverse effects, and the non-financial and financial costs of vaccination.

Prioritise vaccines for diseases that are:

• common and of significant impact, such as influenza and hepatitis A
• less common, but have severe potential adverse outcomes, such as Japanese encephalitis and rabies

Consider booster doses, where appropriate (see disease-specific chapters in this Handbook for recommendations). If the person is departing for travel soon, consider an accelerated schedule, if appropriate, such as for hepatitis B vaccine or the combination hepatitis A-hepatitis B vaccine (see Hepatitis A and Hepatitis B). Although immunity may be established sooner with the accelerated schedule, people who receive an accelerated schedule need another dose about a year later to complete the course and ensure long-term protection.

See also Infographic. Vaccination for international travellers.

Cholera

Most travellers do not need cholera vaccine.^14,15 The risk of a traveller acquiring cholera is very low if they avoid contaminated food and water.

No country requires travellers to have certification of cholera vaccination. No country has official entry requirements for cholera vaccination

See also Cholera.

Hepatitis A

Hepatitis A vaccine is recommended for all travellers ≥1 year of age travelling to moderately or highly endemic countries (including all developing countries). The exceptions are people who have evidence of natural immunity after previous infection.

Normal human immunoglobulin is no longer used to protect travellers against hepatitis A.

See also Hepatitis A.

Japanese encephalitis

Japanese encephalitis (JE) vaccine is recommended for travellers spending a month or more in endemic areas in Asia, Papua New Guinea or the outer islands of Torres Strait during the JE virus transmission season.

Consider JE vaccination for shorter-term travellers, particularly if:

• travel is during the wet season 
• travel may be repeated
• the person will spend a lot of time outdoors 
• the person’s accommodation has no air-conditioning, screens or bed nets

Check a reputable source before travel for information about JE virus activity — for example, Health Information for International Travel (the ‘Yellow Book’).¹⁶

A traveller’s overall risk of acquiring JE in JE-endemic countries is likely to be low (<1 case per 1 million travellers). Determine the specific risk according to the:^17,18

• season of travel
• regions visited 
• duration of travel
• extent of outdoor activity
• extent to which the person avoids mosquito bites 

See also Japanese encephalitis.

Rabies

Before travel to rabies-endemic regions, advise people about:

• the risk of rabies infection
• avoiding close contact with wild, stray and domestic animals — especially dogs, cats, monkeys and bats 
• the importance of appropriate immediate wound care of all animal bites and scratches 

See also Rabies and other lyssaviruses, including Australian bat lyssavirus.

Recommendations for rabies vaccination as pre-exposure prophylaxis

When deciding whether to give a pre-travel prophylactic rabies vaccination, assess the:

• likelihood of exposure to potentially rabid animals
• access to appropriate health care and availability of post-exposure prophylaxis, including rabies immunoglobulin, should there be an at-risk exposure
• timeliness of access to health care after exposure

Use a lower threshold for recommending rabies pre-exposure prophylaxis for children travelling to endemic areas.

Benefits of vaccination as pre-exposure prophylaxis

Pre-travel rabies vaccination:

• ensures that the traveller has received a safe and efficacious vaccine
• simplifies the management of a subsequent exposure because the person will need fewer doses of vaccine
• means that rabies immunoglobulin — which is often extremely expensive, and difficult or even impossible to obtain in many developing countries — is not needed
• reduces the urgency of post-exposure prophylaxis

Tick-borne encephalitis

Tick-borne encephalitis (TBE) is caused by a tick-borne RNA flavivirus. The disease may involve the central nervous system. TBE is prevalent in parts of central and northern European temperate regions, and across northern Asia. Travellers are at risk when hiking or camping in forested areas in endemic regions during the summer months.

Safe and effective vaccines are available. Vaccination is recommended only for people with a high risk of exposure.

TBE vaccine is not registered in Australia, but a small stock of vaccine may be available for use under the Special Access Scheme.

Tuberculosis

Vaccination with BCG (bacille Calmette–Guérin) vaccine is generally recommended for tuberculin-negative children <5 years of age who will be staying in high-risk countries for an extended period (3 months or longer).

Vaccinating older children and adults appears to be less beneficial. However, consider vaccinating tuberculin-negative children aged ≥5 years but <16 years who may be living or travelling for long periods in high-risk countries.

A high-risk country is one that has a tuberculosis incidence of >40 per 100,000 population.

For travellers who need BCG vaccine, consider the following precautions when scheduling their vaccination visits:

• If possible, give BCG vaccine at least 3 months before the person will arrive in an endemic area.
• Give other live viral vaccines (for example, MMR, varicella, yellow fever) at the same time or with a minimum 4-week interval after BCG vaccination.
• A tuberculin skin test (TST; Mantoux), performed by trained and accredited healthcare practitioners, is recommended before receiving BCG vaccine for all individuals (except infants aged <6 months).
• People may suppress reactions to tuberculin for 4–6 weeks after viral infections or live viral vaccines, particularly measles infection and measles-containing vaccines.

State and territory tuberculosis services can provide tuberculin skin tests and BCG vaccine.

See also Tuberculosis.

Typhoid

Typhoid vaccine may be recommended for travellers ≥2 years of age travelling to endemic regions, including: 

• the Indian subcontinent
• most Southeast Asian countries 
• several South Pacific nations, including Papua New Guinea 

This advice is also relevant for those travelling to endemic regions to visit friends and relatives.

Inactivated parenteral and live oral typhoid vaccine formulations are available.

See also Typhoid fever.

Yellow fever

Yellow fever vaccine is recommended for all people ≥9 months of age travelling to, or living in, an area with a risk of yellow fever virus transmission.¹⁹

To minimise the risk of introducing yellow fever, some countries require documented evidence of yellow fever vaccination for entry, in line with the International Health Regulations (see Vaccines required by the International Health Regulations or for entry into specific countries).

When assessing the need for yellow fever vaccination, consider:

• the risk of the person being infected with yellow fever virus
• country entry requirements
• individual factors such as age, pregnancy and underlying medical conditions 

Vaccination is generally not recommended for travel to areas with a low probability of yellow fever virus exposure — that is: 

• where human yellow fever cases have never been reported 
• where evidence suggests only low levels of yellow fever virus transmission in the past 

However, consider vaccination for a small subset of travellers to lower-risk areas who are at increased risk of exposure to mosquitoes or who are unable to avoid mosquito bites.¹⁹

People aged ≥60 years are at increased risk of severe adverse events after primary yellow fever vaccination. Weigh the adverse effects of vaccinating people in this age group against the potential for yellow fever virus exposure and, in turn, the benefits of vaccination.²⁰

See also Yellow fever.

Booster doses

Most people do not need a booster dose of yellow fever vaccine. A single dose induces protective antibody levels that last for many decades. However, certain people are recommended to receive a booster if their last dose was more than 10 years ago and they are at ongoing risk of yellow fever virus infection. See Yellow fever.

Yellow fever requirements

The International Health Regulations require yellow fever vaccination for travelling in certain circumstances. This is to:

• protect travellers who are likely to be exposed to yellow fever 
• stop importation of the virus into countries that have the relevant vectors (see Yellow fever).

Some countries may require documented evidence of yellow fever vaccination as a condition of entry or exit (see Planning and documenting vaccines). This includes countries that do not currently have yellow fever circulating.

Australia’s yellow fever travel requirements are detailed in the Australian Government Department of Health’s yellow fever fact sheet.

Contact the relevant embassies or consulates in Australia to confirm the entry requirements for yellow fever vaccination for the countries a traveller intends to enter or transit through. 

Requirements for travellers to Mecca

Each year, Saudi Arabia’s Ministry of Health publishes the requirements and recommendations for entry visas for travellers on pilgrimage to Mecca (Hajj and Umra).¹⁴

For pilgrims travelling directly from Australia, only evidence of MenACWY vaccination is currently mandatory. However, check the current requirements when advising prospective Hajj and Umra pilgrims (see Meningococcal disease and Accessing up-to-date travel information).

Temporary requirements

The International Health Regulations may temporarily introduce requirements for other vaccine-preventable diseases in response to changes in disease epidemiology that are of international health concern. An example is for polio vaccination.

Because country vaccination requirements are subject to change at any time, confirm all current vaccination requirements for the countries a traveller intends to enter or transit through before travel. See Poliomyelitis and Accessing up-to-date travel information.

Ideally, start vaccination courses early enough before departure to allow:

• monitoring of any possible adverse events 
• time for adequate immunity to develop

Requirements for multiple vaccines

A traveller may need multiple vaccines before they depart. Apply the standard recommendations and precautions when giving multiple vaccines (see Administration of vaccines).

A traveller may need more than 1 clinic visit if they need multiple vaccines or doses (for example, rabies pre-exposure prophylaxis or hepatitis B vaccine). Pay special attention to scheduling of these visits, and consider:

• dose interval precautions (for example, for multiple live vaccines)
• requirements for pre-vaccination tests (for example, tuberculin skin test)
• potential interference by some antimalarials, if relevant (for example, rabies vaccine)

Documentation and certificates

It is important to document travel vaccines: 

• in the clinic’s record
• in the traveller’s record that they can carry with them 
• on the Australian Immunisation Register

The record should also include all the other routinely recommended vaccines that the traveller has ever received. 

For yellow fever vaccination, a traveller needs to have an International Certificate of Vaccination or Prophylaxis (ICVP), which only Yellow Fever Vaccination Centres can provide under the International Health Regulations (see Yellow fever). 

Travellers may also need an ICVP for other vaccine-preventable diseases, such as polio, based on temporary recommendations.

See also Accessing up-to-date travel information.

See Vaccination for women who are planning pregnancy, pregnant or breastfeeding, Vaccination for people who are immunocompromised and the disease-specific chapters in this Handbook for recommendations for travellers who are pregnant or immunocompromised.

International travellers’ health risks constantly change. Up-to-date information, and knowledge of the changing epidemiology and current outbreaks of infectious and emerging diseases are essential. Reliable online information sources include:

• World Health Organization (WHO) for disease outbreak news, and its Travel and health section for specific advice on travel and health, including travel vaccination recommendations
• Travelers’ health, United States Centers for Disease Control and Prevention (CDC)
• Travel health information, Australian Government Department of Health
• Smartraveller, the Australian Government’s travel advisory and consular information service, which provides up-to-date advice about health, safety and other risks of specific destinations for Australian travellers

The following resources have comprehensive technical advice on international travel and health, including vaccination:

• the latest edition of WHO’s International travel and health
• the CDC’s Health Information for International Travel (the ‘Yellow Book’)

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