Can Oral Vaccines Do What Syringes Can’t? Inside WSU’s Bold Plan to Finally Outrun Rabies
Rabies is one of those diseases every veterinary professional knows well and still finds deeply frustrating. It is 100 percent fatal once clinical signs appear, entirely preventable, and yet it continues to kill an estimated 60,000 people every year. Nearly all of those deaths occur in Africa and Asia and most are caused by canine rabies. Now, a new Washington State University-led study is testing whether a simple shift in strategy could help close one of the biggest gaps in global rabies control.
Backed by a $665,000 grant from the National Institutes of Health, the five-year project will evaluate whether adding oral rabies vaccines to traditional injectable campaigns can meaningfully increase vaccination coverage in free-roaming and hard-to-handle dogs in Tanzania. If successful, the approach could change how mass dog vaccination is done in some of the world’s most vulnerable communities.
The science behind rabies control is straightforward. Vaccinate at least 70 percent of the dog population and transmission collapses. In practice, hitting that threshold is anything but easy. Traditional rabies campaigns rely on injectable vaccines and on dog owners bringing animals to centralized vaccination points. That model works reasonably well for owned, easily handled dogs. It fails for dogs that roam freely, resist restraint, or belong to households that cannot access vaccination sites. In many rural areas, these missed dogs make up a significant portion of the population, leaving vaccination coverage perpetually below the level needed to stop transmission. Ahmed Lugelo, a graduate student leading the study under the supervision of Dr. Felix Lankester at WSU’s Paul G. Allen School for Global Health, summed it up clearly. Injectable vaccines remain the most cost-effective tool for dogs that can be handled safely, but catching every dog is time-consuming, risky, and sometimes impossible. Those missed dogs keep rabies circulating.
Why oral rabies vaccination is back in the spotlight
Oral rabies vaccination involves distributing edible baits that contain vaccine, allowing dogs to immunize themselves without restraint. For veterinary professionals, this idea is not new. Oral vaccines have already been used to eliminate rabies in wildlife populations across Europe and North America. Foxes, raccoons, and coyotes have all been successfully targeted using this approach. What is newer is applying oral vaccination at scale in domestic dog populations. Smaller studies in India, Thailand, and Haiti have shown promising results when oral baits are added to standard injection campaigns. Overall coverage increases, especially among dogs that would otherwise remain unvaccinated. The WSU-led study will be the largest and most rigorous test of this combined strategy to date.
The trial will take place across 36 wards in northern Tanzania, each made up of multiple villages. Wards will be randomly assigned to one of two groups. One group will receive standard injectable rabies vaccination only. The other group will receive both injectable vaccines and oral vaccine baits. This design allows researchers to directly compare vaccination coverage, costs, and operational challenges between the two approaches. The team will also track downstream outcomes, including dog bite injuries and rabies cases in both dogs and people. Cost is a central question. Injectable rabies vaccines can cost as little as $0.50 per dose, while oral baits may range from $2 to $4 each. At first glance, oral vaccination looks expensive. The hypothesis is that higher upfront costs may be offset by faster achievement of herd immunity, fewer human exposures, and reduced reliance on costly post-exposure prophylaxis.
Another major barrier to rabies control in low-resource settings is vaccine storage. Many rabies vaccines require refrigeration, which is difficult to maintain in remote areas without reliable electricity. As part of the study, researchers will evaluate whether the oral vaccine remains effective when stored in locally made clay coolers known as Zeepots. These devices can keep temperatures below 77 degrees Fahrenheit without electricity. If proven effective, this could dramatically simplify vaccine logistics and make large-scale campaigns more feasible.
For veterinarians, this project is a reminder that rabies control is not just a medical problem but a systems problem. It sits at the intersection of animal behavior, human behavior, economics, and infrastructure. Oral vaccination does not replace injectable vaccines but may finally give public health teams a way to reach the dogs that have always been left behind. The modeling component of the study will also be critical. By linking improved vaccination coverage to reductions in dog bites and human rabies cases, the research aims to provide policymakers with the data needed to justify investment in combined vaccination strategies. If the results are strong, this work could influence rabies control programs far beyond Tanzania and help accelerate progress toward global rabies elimination goals.
