05/04/2026
We describe a case of a 43-year-old female who developed Bordetella bronchiseptica infection following zoonotic transmission after intranasal vaccination of her dog.
Two weeks after the dog received a live attenuated intranasal B. bronchiseptica vaccine (Nobivac KC), the patient developed:
- bronchitis
- malaise
- low-grade fever, with persistence of clinical signs beyond one week.
Notably, the patient had a history of axial spondylarthritis and had been receiving etanercept (a TNF-α inhibitor) for five years, which likely increased susceptibility to opportunistic infection. TNF-α inhibitors are associated with up to a twofold increase in infection risk.
At presentation, hematologic parameters and C-reactive protein were within normal limits, and thoracic imaging was unremarkable. Multiplex PCR was negative for viral pathogens but indicated a Bordetella species infection, which was subsequently confirmed as B. bronchiseptica on sputum culture.
Initial treatment with azithromycin (500 mg once daily for 3 days) was followed by trimethoprim/sulfamethoxazole (960 mg twice daily for 14 days), resulting in gradual clinical improvement.
Genomic analysis using core genome multilocus sequence typing demonstrated only three allelic differences between the patient isolate and the vaccine strain, confirming the vaccine as the most likely source of infection.
Live attenuated intranasal B. bronchiseptica vaccines are widely regarded as safe; however, they contain viable organisms capable of post-vaccination shedding, which may persist for prolonged periods. Although zoonotic transmission is rare, this case represents the first confirmed report of vaccine-derived transmission from dog to human.
This report highlights the importance of considering zoonotic exposure in atypical respiratory infections and exercising caution when using live attenuated vaccines in households with immunocompromised individuals.
Recommendation: In households with immunocompromised individuals, clinicians should consider the use of non-live (parenteral) alternatives to intranasal Bordetella vaccines when appropriate, and advise on minimizing close contact during the post-vaccination shedding period.
Kraai, I., Knoester, M., Bathoorn, E., Bakker, M., & Nijland, M. (2023). Zoonotic transmission of vaccine-derived Bordetella bronchiseptica. Open Forum Infectious Diseases.