Systematic Booster after Rabies Pre-Exposure Prophylaxis to Alleviate Rabies Antibody Monitoring in Individuals at Risk of Occupational Exposure

Abstract

Pre-exposure rabies prophylaxis (PrEP) is recommended for people at frequent or increased risk of professional exposure to lyssavirus (including rabies virus). PrEP provides protection against unrecognized exposure. After the primary vaccination, one’s immune response against rabies may decline over time. We aimed to evaluate the immune response to rabies in individuals immunized for occupational reasons before and after a booster dose of the rabies vaccine. With this aim, we retrospectively documented factors associated with an inadequate response in individuals vaccinated for occupational purposes. Our findings analyzed data from 498 vaccinated individuals and found that 17.2% of participants had an inadequate antibody titration documented after their primary vaccination without the booster, while inadequate response after an additional booster of the vaccine was evidenced in 0.5% of tested participants. This study showed that a single booster dose of vaccine after PrEP conferred a high and long-term immune response in nearly all individuals except for rare, low responders. A systematic rabies booster after primary vaccination may result in alleviating the monitoring strategy of post-PrEP antibody titers among exposed professionals.

Immune response after rabies pre‐exposure prophylaxis and a booster dose in Australian bat carers

“…Only one participant was found to be antibody-negative >3 years post-booster dose. This is in line with previous research supporting that a single booster dose after PrEP could confer high and long-term immune response in almost all individuals except for rare, low responders (Parize et al, 2021).…”

“…Only one participant was found to be antibody‐negative >3 years post‐booster dose. This is in line with previous research supporting that a single booster dose after PrEP could confer high and long‐term immune response in almost all individuals except for rare, low responders (Parize et al, 2021 ). Our findings suggest that the 3‐year interval between the first booster dose and a serology test recommended by the Australian Immunization Handbook is adequate to protect this group of individuals from the high chances of an animal inadvertently scratching individuals with ongoing occupational exposure (Morris et al, 2007 ) and the devastating consequences of rabies infection.…”

Structure of the rabies virus glycoprotein trimer bound to a prefusion-specific neutralizing antibody

“…Rabies vaccines for human use consist of inactivated virus and have existed since the late 1800s but do not elicit lifelong immunity despite being fully protective in the short term (6 months to a year after vaccination). In humans, levels of vaccine-elicited neutralizing antibodies usually wane 1 to 5 years after vaccination ( 2 ), and frequent revaccination is required to maintain neutralizing antibody titers understood to provide protection against rabies infection ( 3 ). Unvaccinated individuals who are exposed to rabies are given postexposure prophylaxis consisting of polyclonal antibodies derived from sera of vaccinated individuals or immunized horses and multiple doses of the rabies vaccine ( 4 ).…”

Rabies Neglected Modes of Transmission in Pakistan

“…Certain occupations that involve close contact with animals or animal tissues may expose workers to rabies (Parize et al, 2021). Veterinarians, animal control workers, researchers, and laboratory workers may be more likely to be exposed if they handle rabies-infected animals or work with the rabies virus in the laboratory (Rupprecht et al, 2006).…”