Use of a Modified Preexposure Prophylaxis Vaccination Schedule to Prevent Human Rabies

Recommendations of the Advisory Committee on Immunization Practices -- United States, 2022

Agam K. Rao, MD; Deborah Briggs, PhD; Susan M. Moore, PhD; Florence Whitehill, DVM; Doug Campos-Outcalt, MD; Rebecca L. Morgan, PhD; Ryan M. Wallace, DVM; José R. Romero, MD; Lynn Bahta, MPH; Sharon E. Frey, MD; Jesse D. Blanton, DrPH


Morbidity and Mortality Weekly Report. 2022;71(18):619-627. 

In This Article

Implications of These Updates

More persons who are recommended to receive rabies PrEP might be vaccinated because the 2-dose series recommended in these updates is associated with lower out-of-pocket costs and takes less time to complete. Persons with only short-term (≤3 years) risk for rabies (risk category 4) require no additional titer or booster doses, and last-minute travelers who previously were not vaccinated because the 3-dose series required ≥21 days might now be vaccinated because only 1 week is needed to complete the 2-dose primary series.

The updates might also facilitate improved adherence to evidence-based ACIP recommendations. As previously mentioned, in the past, some persons recommended to have serial titers checked did not adhere to those recommendations; with this update, many such persons now have the option of a one-time titer check or a one-time booster dose (i.e., a one-time action with two options for accomplishing it). As described in the EtR framework, some persons might prefer the titer option because of the potentially lower cost if a booster is not indicated (i.e., titer is ≥0.5 IU/mL); others might prefer the convenience of proceeding directly to a booster dose. The wide interval during which the titer or booster options can be taken might defray up-front costs and allow persons more time to determine whether they expect risk for rabies >3 years. Appointments for the titer check or booster dose can be scheduled at the time of the 2-dose primary series to ensure adherence to the recommendations.

Persons who received the 3-dose PrEP schedule recommended by ACIP in the past and whose activities place them within risk category 3 require no further titer checks or booster doses; the last vaccine dose they receive as part of the 3-dose series is equivalent to the option provided in these updates for a booster dose during day 21 to year 3. However, frequency of serial titer checks (risk categories 1 and 2) is unchanged, regardless of whether the 2-dose or 3-dose primary series was received by a person.

A consequence of the updated minimum acceptable rabies antibody titer (0.5 IU/mL) is that when titers are checked, more persons might require a booster dose than with the previous minimum acceptable rabies antibody titer level. ACIP concluded that the benefits of the new acceptable titer outweighed this theoretical concern.