People who work with bats, laboratory workers who work with live lyssaviruses and some people who travel to rabies-enzootic areas are recommended to receive rabies vaccine as pre-exposure prophylaxis

Recommended schedule — intramuscular route

The recommended pre-exposure prophylaxis schedule for rabies virus or other lyssavirus infection comprises 3 vaccine doses given by the intramuscular route:

• 1st dose on day 0
• 2nd dose on day 7
• 3rd dose on day 21–28

Alternative route of administration — intradermal route

The intradermal route may be used by suitably qualified and experienced providers (eg travel medicine clinics). See Administration of vaccines. This route is only to be used for pre-exposure vaccination of immunocompetent people. The schedule comprises 3 doses of 0.1 mL each, given by the intradermal route:

• 1st dose on day 0
• 2nd dose on day 7
• 3rd dose on day 21–28

The intradermal route is ‘off-label’ use. If intradermal rabies pre-exposure prophylaxis is considered, it is essential that:

• it is given by immunisation providers who have expertise in, and regularly practise, the intradermal technique, because incorrect administration may mean the person is not adequately protected
• it is not given to people who are immunocompromised
• it is not given to people taking chloroquine, or other antimalarials that are structurally related to chloroquine (such as mefloquine or hydroxychloroquine), at the time of vaccination or within 1 month after vaccination
• the immunisation provider follows procedures for the use of a multidose vial and discards any remaining vaccine after 8 hours or at the end of the vaccination session, whichever occurs first

Alternative schedule — accelerated schedules

Travellers who do not have enough time to complete the 21–28-day schedule may receive an accelerated schedule, but the standard 21–28-day schedule is preferred.

There are 2 options for administering an accelerated schedule, as follows.

Accelerated 3 dose intramuscular schedule:

• 1st dose on day 0
• 2nd dose on day 3
• 3rd dose on day 7

Accelerated 4 dose intradermal schedule comprising 2 vaccine doses at each visit:

• 2 x 0.1 mL injections given at different sites on day 0
• 2 x 0.1 mL injections given at different sites on day 7

Do not use the accelerated intradermal schedule in adults >50 years of age, because studies show that seroconversion is less likely to occur in this age group than in younger people.^1,2

These accelerated schedules provide protection for short-term travel to rabies-enzootic areas. If further travel to rabies-enzootic areas is planned after 1 year, antibody levels may no longer be adequate. A single intramuscular booster dose should be given 1 year after the 1st dose of pre-exposure prophylaxis, regardless of the administration route for the original pre-exposure prophylaxis course.

Booster doses

Booster doses of rabies vaccine are recommended for immunised people who have ongoing occupational exposure to lyssaviruses in Australia or overseas. See People with ongoing occupational exposure to lyssaviruses are recommended to receive booster doses of rabies vaccine.

Serological testing for people who received pre-exposure prophylaxis by the intradermal route

If pre-exposure prophylaxis was received by the intradermal route, check the rabies antibody level 2–4 weeks after finishing the pre-exposure course to ensure that VNAb (rabies virus neutralising antibody) levels are ≥0.5 IU per mL. Seek expert advice via state or territory health authorities if the titre is <0.5 IU per mL.

If there will be insufficient time before travel for serological testing to be performed, the intramuscular route for vaccination should be used.

Serological testing for people who are immunocompromised

People who are immunocompromised should have their VNAb titres checked 2–4 weeks after the 3rd intramuscular dose of vaccine in a pre-exposure prophylaxis schedule. Give a further dose if the titre is <0.5 IU per mL, and repeat serological testing. If the titre remains <0.5 IU per mL, seek advice via state or territory health authorities.

Rationale for pre-exposure prophylaxis

Pre-exposure prophylaxis simplifies how a potential subsequent exposure to rabies virus or Australian bat lyssavirus is managed because:

• the person needs fewer doses of rabies vaccine in the post-exposure phase
• the person does not need RIG (rabies immunoglobulin) unless they are severely immunocompromised

This is particularly important because RIG — either human (HRIG) or equine (ERIG) — can be difficult to obtain and is expensive, and its safety cannot be guaranteed in many rabies-enzootic developing countries. See also Vaccination after potential exposure to rabies virus or other lyssaviruses (post-exposure prophylaxis).