Recommendation for Missed Day 28 Dose After Completing First 4 Doses
No additional dose is needed—the patient has completed adequate post-exposure prophylaxis and is protected against rabies. 1
Rationale Based on Current Guidelines
The Advisory Committee on Immunization Practices (ACIP) revised rabies post-exposure prophylaxis in 2010, reducing the standard regimen from 5 doses to 4 doses administered on days 0,3,7, and 14 for previously unvaccinated, immunocompetent persons. 1 The day 28 dose is no longer part of the recommended schedule for healthy individuals. 1
Key Points Supporting This Recommendation
The 4-dose regimen (days 0,3,7,14) is the current standard of care for previously unvaccinated persons receiving rabies immune globulin (RIG) and is considered complete prophylaxis. 1, 2
All healthy persons who complete a 4-dose regimen demonstrate adequate antibody response against rabies virus, with protective titers achieved by day 14. 1
Routine serologic testing after completing the 4-dose series is unnecessary in immunocompetent patients, as seroconversion is expected in all cases. 1
The patient received RIG on day 0, which provides immediate passive immunity during the critical first 7-10 days while vaccine-induced antibodies develop. 2
When the 5-Dose Regimen (Including Day 28) Is Required
The 5-dose regimen on days 0,3,7,14, and 28 is reserved exclusively for immunocompromised patients, including those on corticosteroids, other immunosuppressive agents, antimalarials, or with immunosuppressive illnesses. 1, 2
If this patient has no immunocompromising conditions, the 4-dose series they completed is sufficient. 1
If the patient is immunocompromised, they should have received the 5-dose regimen from the start, and missing the day 28 dose would require administration of that dose now plus serologic testing 1-2 weeks later to confirm adequate antibody response. 1, 2
Evidence Supporting Incomplete Series Safety
Over 1,000 persons annually in the United States receive only 3-4 doses instead of complete regimens, with no documented cases of rabies developing, even when >30% had confirmed exposure to rabid animals. 2
No case of human rabies in the United States has ever been attributed to receiving fewer than the complete vaccine course. 2
Virus-neutralizing antibodies peak by approximately day 14-28 after starting vaccination, meaning the critical protective window occurs well before any theoretical fifth dose. 2
Clinical Action
Document that the patient completed the recommended 4-dose post-exposure prophylaxis regimen per current ACIP guidelines. 1 No further vaccination is needed unless the patient is immunocompromised, in which case immediate consultation with infectious disease specialists and public health authorities is warranted. 1, 2