Pick your poison: One Health approach for snakebite treatment
In a nation full of wildlife that creeps and slithers through our fields, it’s only natural that Filipinos have a deep fear of snakes and their venom. Killing seems like the easy solution to the fatal, dangerous snakebites, but there’s a better way: one that protects both us and the snakes.
You are walking along a familiar path, moonlight-guided, on the way home after a grueling day of work. You pass by the university’s hallowed halls, windows dark. Next comes the local elementary school, Gabaldon empty. You walk slowly toward the abandoned house, where shadows abound.
Out of nowhere, a cobra appears. What do you do?
If you are the man who encountered a Samar cobra near Visayas State University in March this year, you whack the snake repeatedly with a malunggay branch then cut its head off with a sundang. It is a brutal death for the snake, but it is an act rooted in cultural beliefs. After all, it is said that only beheading the snake can protect you from the supernatural karma that comes with killing it.
Killing seems like the natural, fear-laden response to the threat of snakes. But according to those who care for snakebite patients, killing is the exact opposite solution they advise.
Snakebites are not the full story
Every year, around 13,000 Filipinos are bitten by snakes. For 550 of these victims, the snakebite is fatal.
While it is a problem significantly more prominent in our rural provinces rather than urban cities, it is undeniable that snakebites are a serious health concern. In Eastern Visayas, the Samar cobra or Naja samarensis is a major cause of severe snakebites, and nearly half of its victims have been farmers and students. Most were unlucky to come across the snake while farming or walking by, and a few were bitten while they were asleep.
“Locals perceive snakes as dangerous, evil, and a threat,” said Dr. Patrick Tiglao, founding president of the Philippine Toxinology Society. He specializes in emergency medicine, with his research spanning the treatment and economic burden of snakebites.
Many cultural factors contribute to the fear of snakes. More than the real dangers of snake venom, public perception around the “evilness” of snakes is immortalized in our stories. It reaches as far back to the Biblical depiction of the devil as a snake giving the apple to Eve, and in local teleseryes, the snake-haired Valentina remains Darna’s most iconic archnemesis. In homes, snakes are perhaps used by parents to scare children when they misbehave. The fear of snakes is passed down from generation to generation, despite the fact that not all snakes pose a threat to human life.
Among the more common snake encounters in the country are the maninina, the Philippine rat snake; the paparay, the common wolf snake; and the sawa, the reticulated python. All three are non-venomous.
“The misconception that all snakes are venomous leads to indiscriminate killing, ignoring their ecological value,” wrote Tiglao and his co-authors in the paper documenting the Samar cobra incident.
Snakes have been said to be a natural form of pest control. When left alone in their habitats, snakes keep rodent populations in check. They eat mice, rats, and small mammals—animals that can damage crops and spread diseases—with some snake species reported to eat at least 100 rodents a year. Cobras specifically are opportunistic eaters and prey on whatever is available, which means they can also target invasive species that threaten local ecosystems. In Davao, the Samar cobra was observed to prey on cane toads, while another report covered a Samar cobra attempting to eat the non-native banded bullfrog.
Studies on Philippine snakes remain very limited, however, which has led to a glaring research gap: the production of antivenom.
A scarcity of antivenoms
The only antivenom available in the Philippines is the purified cobra antivenom vaccine (PCAV). It is solely produced by the Research Institute for Tropical Medicine.
The good news is that PCAV is effective. In a study of snakebite patients at the Eastern Visayas Medical Center, more than 90 percent of patients receiving PCAV were successfully treated. Strikingly, half of these cases only needed one to two ampoules of PCAV before their conditions improved, far below the five ampoules recommended to treat severe cases. Its effectiveness persisted even when the treatment could only be administered six hours after the bite incident.
The bad news is that PCAV is scarce. Just this December, the Commission on Audit reported that thousands of requests for PCAV this year were left unfulfilled. Out of 4,657 requests, only 1,825 ampoules were distributed. Over a thousand requests were neglected, while over a thousand more were outright rejected.
“The non-allocation implies that the current quantity produced is not enough and that the allocation process is not effective and efficient to cater to the current demand,” the report said.
Another challenge lies in the fact that PCAV was only developed as a counter against a specific snake species. PCAV is made from the Philippine cobra, Naja philippinensis. While it can treat snakebites from the closely related Samar cobra, as many as six ampoules are necessary for successful treatment. No antivenoms have been developed against other venomous snakes, such as pit vipers and coral snakes.
Increasing antivenom production is necessary, but Tiglao warned that this will take a long time. This tedious process begins with collection of the venom from the snake. In the lab and following strict safety standards, the venom is inoculated into an animal that will develop antivenom properties in their blood, much like the process of developing antibodies against bacteria. Purification methods and further testing are then performed to ensure the safety and efficacy of the antivenom product.
“For a new antivenom to be developed in the traditional way, it will take at least 5-10 years to complete from research to production,” Tiglao said.
A different kind of treatment
While antivenom treatments are necessary for those who have already been bitten, an alternative approach to preventing venomous encounters in the first place may lie in the One Health framework.
Supported by the World Health Organization as well as local healthcare policies, the core principle of One Health is that everything is connected: human health, animal health, and environmental health. It was developed as a response to zoonotic diseases, gaining ground during the global spread of bird flu, and resurging again amid the COVID-19 pandemic. One Health puts forward that, since animals can spread disease to humans, caring for animals must be an essential aspect of public health.
One Health is integral to the Philippine Toxinology Society. Since 2017, the group has integrated environmental conservation approaches into their training programs for island communities and local government units. It was also a central point of discussion during the first Philippine Toxinology Congress, which the group organized just this December in Palawan.
“We should not kill the threat; we should learn how to live with the threat. We always have this concept of ‘Prevention is better than cure’ but prevention must start from the ground up,” said Prof. Madya Ahmad Khaldun Ismail of Malaysia’s Remote Envenomation Consultancy Services.
Tiglao highlights the importance of local governments in implementing these One Health strategies, augmenting the work of science and healthcare specialists.
To address public health concerns while preserving biodiversity, there is a need to not only raise conservation awareness but also conduct epidemiological surveys of snakebites, to better understand where and how these incidents are likely to occur. From there, strategies can be devised to educate communities, especially vulnerable ones, on safe practices and to train healthcare providers.
“Communities can develop safer relationships with endemic species, reducing casualties and unnecessary snake killing,” the authors wrote.
The Samar cobra is among the several snake species that are endemic to the Philippines. But it is losing its natural habitat to deforestation, agriculture, and climate change. The habitat loss pushes snakes closer to fields, schools, and houses, creating more opportunities for snake-human encounters.
It is this, rather than the snake’s storied “evilness,” that leads to snakebites. In the end, they are just animals trying to live. With a One Health approach, we can live alongside them.
