When is immunoglobulin given after a tick bite? - briefly
Immunoglobulin is administered after a tick bite only when the bite presents a high‑risk exposure to a pathogen that requires passive prophylaxis, such as suspected rabies from an unvaccinated animal, and the individual lacks prior immunity. It is given together with the first vaccine dose, preferably within the initial days following exposure.
When is immunoglobulin given after a tick bite? - in detail
Immunoglobulin is administered as part of rabies post‑exposure prophylaxis (PEP) when a tick bite creates a potential exposure to the rabies virus. The passive‑immunity product must be given promptly after the bite, ideally on the same day as wound cleansing, and no later than the seventh day following the incident. Administration is required under the following circumstances:
« The animal from which the tick was removed cannot be observed for ten days because it is dead, missing, or otherwise unavailable »
« The bite occurred in a region where rabies is endemic in wildlife or domestic animals »
« The tick was attached to a mammal known to be a rabies reservoir (e.g., fox, raccoon, bat) and the animal’s health status is uncertain »
If the source animal can be observed and remains healthy throughout the observation period, immunoglobulin is not indicated. The product is also unnecessary for tick‑borne diseases that do not involve rabies, such as Lyme disease, anaplasmosis, or babesiosis.
Dosage and administration details:
- Human rabies immune globulin (HRIG) is given at 20 IU per kilogram of body weight.
- The calculated volume is infiltrated around the wound site as completely as possible; any remaining volume is injected intramuscularly at a site distant from the vaccine administration.
- The rabies vaccine series begins on the same day, with doses on days 0, 3, 7, and 14 (or day 28 for immunocompromised patients).
Contraindications and precautions:
- Known hypersensitivity to human immunoglobulin preparations.
- Severe allergic reactions to previous rabies PEP components.
In summary, passive immunization with rabies immunoglobulin should be provided immediately after a tick bite that poses a credible rabies risk, and it must be completed within a week of exposure, concurrent with the active‑vaccine schedule. The therapy is not used for other tick‑transmitted infections.