It was a rainy day in August 2013 when we made the trip to Dimapur. We wanted to experience first-hand, the problem of cysticercosis in pigs. Dimapur is the entry point for north-eastern states of India and is well connected by road, rail and air. Our final destination was Kohima, the state capital of Nagaland, where the disease is thought to be prevalent. Porcine Cysticercosis (PC) is a disease that can be transmitted from pigs to humans. Once in humans, it can infect the brain resulting into epileptic-like seizures.
During our fact finding mission, we found out something very interesting. Even though the people in Nagaland explained that the chance of getting PC in pigs reared locally were rare, there were high cases of people infected with cysts in the brain. How then, were these people being infected if their locally reared pigs were considered negative for PC?
It turns out that most pigs consumed in the state are transported from outside states like Uttar Pradesh and Bihar. Pigs from peri-urban areas like Lucknow in Uttar Pradesh are collected and transported thousands of miles and end up in places like Dimapur in the north east. This is because pigs in the peri-urban areas are available at cheaper prices since most residents do not eat pork. In addition, the waste produced by these peri-urban areas provides cheap food to the pigs, making the cost of rearing the pigs inexpensive.
But there lies the danger, because eating pigs that have been exposed to such unhygienic conditions puts people at risk from being infected with cysticercosis. The pigs are interacting a lot more with human waste where they can easily pick up a Tenia solium (a tape worm egg found in humans) egg and develop many cysts in the muscle. These can be transferred back to humans through eating infected meat.
The interesting and perhaps more worrisome discovery from our mission was that those rearing and selling the pigs at distant locations are probably unaware of the problem and therefore are unlikely to take any measures against exposing the pigs to the unhygienic conditions, while those who are consuming the meat do not know where the pigs are coming. This is where the government needs to come in, to put in place a countrywide control programme to stop the spread of cysts from pigs. In this way, both the sellers and the consumers will be protected.
This post was originally written as part of World Veterinary Day focusing on Vector-borne diseases with Zoonotic potential. Vector-borne zoonotic diseases are becoming a major public health concern in fact Scientists estimate that more than 6 out of every 10 infectious diseases in humans are spread from animals. At GALVmed, we work on a number of zoonotic diseases not only to protect livestock from these diseases but humans as well.