In Peru, a race to vaccinate dogs as two epidemics collide

A team of workers in Peru, led by Penn Medicine’s Ricardo Castillo-Neyra, led a two-month rabies vaccination campaign.

Last July, public health experts in Philadelphia debated with Peruvian government officials about how to address a growing epidemic in Arequipa, Peru’s second-largest city. The scientists warned that without a vaccination campaign, disease would spread throughout the city of 1 million. But the country’s Ministry of Health officials worried that outdoor clinics could put health workers in danger and lead to mayhem in the streets—fights would break out as the aggressive patients waited to receive their shots, they said.

Person kneeling on ground while their dog is vaccinated on a sidewalk in Peru, the medical workers are wearing PPE and working in a temporary plastic tent bubble to protect against COVID.
Vaccinators in Arequipa reported feeling safer within the booths compare to using only PPE. During a pandemic, reduced workforce meant hiring nonmedical personnel to perform vaccinations, so PPE protocols were harder to follow. (Image: Penn Medicine News)

The epidemic? Rabies. The patients? Canines.

Until last spring, there had been major progress toward eliminating rabies in Latin America, thanks to rabid dog surveillance and removal, along with annual mass vaccination campaigns. In Arequipa, Ricardo Castillo-Neyra, an assistant professor of epidemiology in the Perelman School of Medicine, has collaborated with local public health authorities to lead such efforts for the past six years.

But the introduction of a different infectious disease—COVID-19—threatened to reverse that progress.

As COVID began to take a devastating toll on Peru, the country’s Ministry of Health shifted its focus from rabies prevention to the more immediate threat. Arequipa’s public health officials told Castillo-Neyra that they planned to halt its annual rabies vaccination campaign.

“The vaccine is only effective for one year. After that, antibodies decline quickly. So if you skip an annual campaign, most of the dog population becomes susceptible,” Castillo-Neyra says.

To measure the impact of COVID-19 on rabies reemergence in Arequipa, Castillo-Neyra and Brinkley Raynor—a dual VMD/Ph.D. candidate in the Perelman School of Medicine and School of Veterinary Medicine—created an epidemiological model to predict the “long-term effects of short-term changes” to the rabies prevention protocols that had been maintained over the past three decades.

With funding from Penn’s Global Engagement Fund, Castillo-Neyra’s team set up 251 vaccination sites between August and October, vaccinating 16,000 dogs in Arequipa during a global pandemic.

That number amounts to about 10% of the estimated population of 150,000 canines. But the veterinarian-turned-epidemiologist knows that 10% better than zero when it comes to preventing zoonotic disease spread.

“It was huge for us,” he says.

Moreover, the success of the campaign proves what can be achieved with a bit of creativity, community input, and meeting people where they are at.

Read more at Penn Medicine News.