Can I give purified Vero cell rabies vaccine (PVRV) as the second dose to a patient who received the first dose of purified chick embryo cell rabies vaccine (PCECV) three days ago, assuming no severe allergies or immunocompromise?

Yes, it is acceptable to give a dose of PVRV (purified Vero cell rabies vaccine) to a patient who received the first dose of purified chick embryo cell (PCECV) rabies vaccine three days earlier. Current rabies post‑exposure prophylaxis guidelines allow the use of any WHO‑prequalified inactivated rabies vaccine for subsequent doses when the originally used product is unavailable, provided the full recommended series is completed. Assuming the patient has no history of severe allergy to vaccine components (e.g., egg protein) and is not severely immunocompromised, you can administer the second dose of PVRV today (day 3) at the standard intramuscular dose (typically 1 mL in the deltoid). Continue the remaining doses according to the chosen schedule (e.g., days 7,14, and 28 for a 5‑dose regimen or days 7 and 14 for a 4‑dose regimen), using PVRV for all subsequent injections. If the patient had a known severe allergy to Vero‑cell products, an alternative WHO‑approved vaccine should be sought, but in the absence of such contraindications, switching to PVRV is safe and will complete the prophylaxis without compromising efficacy.