Too many cross-species diseases like COVID-19 are being overlooked worldwide

The outbreak of COVID-19 has proven as disruptive globally as it has deadly, yet despite rising cases and fatalities, it remains the tip of the iceberg of zoonotic diseases. 

More than 200 different illnesses can pass from animals to people, most of which originate in wildlife, causing an estimated billion cases of sickness in people and millions of deaths every year.

Many of these diseases are commonly found in low-income countries, creating invisible epidemics that fail to attract the same level of global attention as COVID-19. 

Cysticercosis, an infection caused by a tapeworm in wild and free-roaming pigs, for example, is estimated to affect 50 million people in countries like Rwanda, Nigeria and Ghana every year while leptospirosis, often carried by rats, kills more than 100,000 people annually.

To bring an end to these scourges of public health, the global community must increase access to existing veterinary medicine to stop preventable diseases from spilling over to people, and expand research into neglected areas such as viruses in wildlife.

Rabies, for example, kills around 60,000 people every year and remains a threat for 5.5 billion people around the world, despite the existence of an inexpensive vaccine for dogs, which prevents them from passing the disease on to people.

Similarly, the parasitic disease, leishmaniasis, is on the rise in the Americas but a canine vaccine can protect both dogs and people from the illness, for which there is currently no effective human vaccine. 

For the cases in which a vaccine exists to prevent zoonotic disease reaching people, improving access to veterinarians and veterinary products, particularly in remote or rural areas, offers the best chance of ending these ongoing plagues.

And to prevent zoonotic disease from impacting broader social development, including poverty and productivity, animal health must therefore become a core part of national and international health policies. 

At the same time, COVID-19 has also served as a devastating reminder that more research and development is needed in managing the disease threats posed by wildlife.

For all the obvious challenges in monitoring and controlling disease in natural habitats, the wealth of veterinary expertise around domestic animals and diseases can offer solutions.

In the first instance, greater surveillance of health threats and disease spread in wildlife would help national and global agencies to better prepare for potential outbreaks in the same way that livestock disease is currently monitored across countries.

Strengthening and extending initiatives like the Global Early Warning System, which monitors health threats at the cross-section of animals, humans and ecosystems, would provide more and better data to support early interventions.

Thereafter, the success of vaccination in eradicating the disease rinderpest in both cattle and wild buffalo offers lessons for disease control in other wildlife populations.

International agencies coordinated an extensive vaccination program, including in remote areas, to ensure enough animals received immunity while others have developed oral vaccines that can be laid out for populations of wild animals to target diseases like rabies.

For now, dealing with the COVID-19 pandemic has become the first priority for almost every country around the world.

But if the same effort could be made to tackle diseases in animals before they reach people in the first place, the world could also end many more health crises, both current and future. 

Carel du Marchie Sarvaas, executive director of the global animal medicines association HealthforAnimals.