Merck Animal Health launches nonadjuvanted rabies vaccines for dogs and cats as human exposures rise

Merck Animal Health has announced the US availability of NOBIVAC NXT 1-Rabies and NOBIVAC NXT 3-Rabies, next-generation rabies vaccines for healthy dogs and cats 12 weeks or older. NOBIVAC NXT 3-Rabies provides a 3-year duration of immunity after a repeat dose.¹

The launch follows a Health Alert Network (HAN) Health Advisory from the CDC on a nationwide increase in reported human rabies exposures, underscoring the role companion animal vaccination plays in protecting both pets and people.²

Both vaccines are built on the company's NOBIVAC NXT platform and are nonadjuvanted, preservative-free, antibiotic-free, and thimerosal-free. They are delivered in a low-volume 0.5-mL dose intended to support comfort and ease of administration for veterinary teams and patients.¹

“With NOBIVAC NXT Rabies, veterinarians now have an innovative option designed to provide trusted rabies protection while supporting a positive vaccination experience for pets, veterinary teams and pet owners alike,” said Meg Conlon, DVM, executive director, US companion animal veterinary services, Merck Animal Health, in the release.¹

“Vaccination remains a cornerstone of rabies prevention, but advances in vaccine technology also create opportunities to improve the vaccination experience,” added Laura Greene, DVM, DACVIM (SAIM), internal veterinary medicine specialist, Merck Animal Health.¹

Rabies activity is climbing

Rabies is a zoonotic viral disease that is nearly 100% fatal but preventable when post-exposure prophylaxis (PEP) is given appropriately before symptoms begin. Infected animals can transmit the virus to humans and other animals through bites, scratches, or oral secretions.²

Since July 2026, multiple US jurisdictions have reported local increases in human exposures involving both known rabies vectors and species in which rabies is less commonly reported, according to the CDC. From July through August, the agency received 17% more rabies-related inquiries than during the same period in 2025, including reports of mass exposure events, and at least 8 state health departments reported increased PEP use, PEP administration errors, or both.²

Related: Q&A: A rabies expert on rising exposure reports and keeping human cases rare

Each year, roughly 100,000 people in the US receive PEP. As of September 2, 2026, use of the licensed human rabies vaccines and human rabies immune globulin (HRIG) products had climbed an estimated 33% and 76%, respectively, from the same period last year. Although no shortage exists, a typical PEP course costs $11,000 to $14,000 per person.²

What it means for veterinary teams

Veterinarians often sit at the center of the decision about whether a bitten person needs PEP. The CDC notes that PEP generally is not recommended when the biting animal is available for a 10-day observation period, tests negative, or is judged by health officials to pose no rabies risk, and that observing an available animal in consultation with a veterinarian may be a reasonable alternative to testing. The agency also advises people bitten by someone else's pet to request proof of current rabies vaccination, making accurate, accessible vaccination records essential.²

The advisory also gives veterinarians ready-made client talking points: keep pets current on rabies vaccines and away from wildlife, and treat normally nocturnal species, such as bats and raccoons, seen during the day as a warning sign.²

The guidance matters for veterinary team members themselves, too. People who have completed a pre- or post-exposure series—or a partial series with a documented titer of at least 0.5 IU/mL—should receive 2 vaccine doses on days 0 and 3 and no HRIG after an exposure, whereas never-vaccinated people need HRIG plus 4 doses. Misclassifying prior vaccination history is among the common PEP errors the CDC lists, so staff who keep records of their rabies vaccination and titer results can help ensure they receive appropriate care.²

References

1. Merck Animal Health launches NOBIVAC NXT Rabies for dogs and cats in the United States. News release. Merck Animal Health. November 2, 2026. Accessed November 2, 2026. https://www.merck-animal-health.com/news-and-insights/news-releases/merck-animal-health-launches-nobivacr-nxt-rabies-for-dogs-and-cats-in-the-united-states/
2. Nationwide increase in reported human rabies exposures: rabies post-exposure prophylaxis administration. Health Alert Network. Centers for Disease Control and Prevention. September 10, 2026. Accessed November 2, 2026. https://www.cdc.gov/han/php/notices/han00533.html