Recommended Interval for Anti-Rabies Vaccine Booster Doses

Risk-Based Booster Schedule

The Centers for Disease Control and Prevention recommends that individuals who work with live rabies virus in research laboratories or vaccine production facilities should have serum tested for rabies antibody every 6 months 1, 2
Individuals at continuous risk of exposure should receive booster doses when serum titer falls below complete neutralization at a 1:5 serum dilution by the Rapid Fluorescent Focus Inhibition Test (RFFIT) 1, 2, 3
The Centers for Disease Control and Prevention recommends that individuals at frequent risk of exposure, such as laboratory workers, spelunkers, veterinarians, and animal-control officers, should have serum tested for rabies antibody every 2 years 1, 2, 4
A booster dose is required for individuals at frequent risk if the titer is less than complete neutralization at a 1:5 serum dilution by RFFIT 1
Alternatively, a booster can be administered in lieu of a titer determination for individuals at frequent risk 1

The Centers for Disease Control and Prevention recommends that previously vaccinated individuals exposed to rabies should receive two IM doses of vaccine, one immediately and one 3 days later 1, 5
Rabies immunoglobulin is unnecessary and should not be given to previously vaccinated individuals exposed to rabies 1, 5
The Centers for Disease Control and Prevention recommends that immunosuppressed individuals should have their antibody titers checked after vaccination 1, 2
Failures to seroconvert after vaccination in immunosuppressed individuals should be managed in consultation with appropriate public health officials 2

The Centers for Disease Control and Prevention recommends that antibody titers should be used to monitor the relative rabies immune status over time among persons at higher than normal risk for exposure 2
Two years after primary pre-exposure vaccination, 93%-98% of persons who received the 3-dose pre-exposure series intramuscularly and 83%-95% of persons who received the 3-dose series intradermally still showed complete neutralization of challenge virus at a dilution of 1:5 2

For continuous risk, the Centers for Disease Control and Prevention recommends testing antibody levels every 6 months and administering booster when titer falls below protective level 1, 2
For frequent risk, the Centers for Disease Control and Prevention recommends testing antibody levels every 2 years and administering booster when titer falls below protective level or giving booster directly without testing 1, 2
For infrequent risk, no routine boosters are required after primary vaccination series 1, 4

The CDC recommends serum rabies‑virus antibody testing every 6 months for laboratory workers handling live virus or vaccine‑production staff, with booster doses given whenever the rapid fluorescent focus inhibition test (RFFIT) titer falls below complete neutralization at a 1:5 dilution. 6

For veterinarians, animal‑control officers, wildlife officers in rabies‑endemic areas, diagnostic laboratory workers, and spelunkers, the CDC advises antibody testing every 2 years and a single booster dose if the RFFIT titer is below complete neutralization at a 1:5 dilution. 6

The CDC states that veterinarians and animal‑control officers in low‑rabies areas, veterinary students, and international travelers do not require routine booster doses after completing the primary pre‑exposure series; boosters are needed only after a documented exposure. 6

The CDC recommends that previously vaccinated individuals who are exposed receive two 1.0 mL intramuscular doses of rabies vaccine—one immediately and a second dose 3 days later—without rabies immunoglobulin (RIG). 6
“Previously vaccinated” is defined by the CDC as having completed a recommended pre‑exposure or post‑exposure regimen of human diploid cell vaccine (HDCV), purified Vero cell rabies vaccine (RVA), or purified chick embryo cell vaccine (PCEC), or having a documented protective antibody titer. 6
The CDC advises that RIG should not be administered to previously vaccinated persons because it can inhibit the rapid anamnestic antibody response. 6

The CDC recommends that immunosuppressed individuals receive the full 5‑dose rabies vaccine series even if previously vaccinated, with antibody titers checked 7–14 days after series completion; failure to seroconvert should be managed in consultation with public‑health officials. 6

The CDC permits a 0.1‑mL intradermal (ID) dose of HDCV for routine pre‑exposure booster vaccination. 6
The CDC notes that RVA and PCEC are not approved for intradermal administration. 6
The CDC advises avoiding intradermal HDCV in persons taking chloroquine or mefloquine for malaria prophylaxis, recommending the standard 1.0 mL intramuscular route instead. 6