Members of the Afrivet One Health team spent a week in the beautiful Eastern Cape Province, rolling out a pilot vaccination campaign in the rural pig population of Upper Gxulu village. The vaccination project is a world-first in South Africa through Afrivet’s caring for the community that it serves and its focus on One Health.
The project aims to tackle a disease known as Neurocysticercosis (NCC), which is a leading cause of serious neurological disorders such as seizures in people living in certain rural settings around the world. The team has been developing and working on this significant project for over 2 years and, despite some challenges and delays caused by the COVID-19 pandemic, and an African Swine Fever outbreak in the Eastern Cape, they were able to ear tag and vaccinate 115 pigs against the tapeworm that is responsible for NCC in humans.
One must ask, what do pigs, people, and epilepsy have in common? NCC is an infection of the central nervous system by larval cysts of the zoonotic cestode Taenia solium. It is considered one of the most majorly neglected (or “orphan”) zoonotic diseases in the world and is a challenge globally- most often in resource-poor communities that live in close contact with their livestock. NCC is caused by a tapeworm that cycles between humans and pigs – (see image below, Citation: The American Journal of Tropical Medicine and Hygiene 98, 2).
Caryn Shacklock, Laboratory manager at Afrivet emphasised
that, “It is most often a problem in conditions where pigs are free-ranging and living in close contact with humans, and where human waste hygiene and sanitation is a challenge.” Of the estimated 50 million people with epilepsy in the world today, 80% live in areas infested with Taenia solium, and in about 30% of these people, the worm is the cause of their epilepsy.
“If a person accidentally ingests tapeworm eggs that are shed in human faeces, the larvae can migrate to the brain, forming a cyst that may result in epilepsy.” The life cycle of the tapeworm is complex and the link between the disease and the consumption of undercooked pork is not easily or commonly understood. It is estimated that the time-lapse between
infection with the worm egg and the symptoms of epilepsy can easily be 5 to 10 years! So, it is quite difficult to assess the prevalence of this disease in a community of people because current infections will only show symptoms of disease years later.
Vuyokazi Makapela, Director of Afrivet says that “Many rural parts of the Eastern Cape province have a high prevalence of this disease. Several studies have been conducted over the years and one study showed that over 60% of the cases of epilepsy diagnosed in human patients in the EC province are caused by NCC. This area poses a unique challenge in the fight against this disease, as many rural households have pigs living in close contact with their owners, and many communities are still making use of pit toilets which are accessible to the pigs.”
The adult tapeworm lives in the human small intestine. Tapeworm eggs are shed in the faeces and if ingested by a pig, the larvae migrate to the muscles and form cysts (called cysticerci). Fortunately, a vaccine has been developed for use in pigs that will render the pig immune to the tapeworm infection
and thus break the cycle of transmission from human to pig. “When used in conjunction with a specific dewormer that will kill the larvae that are encysted in the pig’s muscles, we are able to eliminate NCC from a community in a short period of time. This solution is monumental in a time when our country’s health care system and facilities are already under immense strain due to Covid-19.”
After a number of community engagements and education sessions, the Afrivet team, assisted by the Keiskammahoek state vet and animal health technicians, visited each household in the area and administered the vaccine to all healthy pigs over the age of 8 weeks. The process will be repeated in 4 weeks’ time when the second vaccination and an oral dose of the dewormer will be given to each of the pigs.
Caryn went on to explain that “After we inspected each pig as we injected it, we found an alarmingly high number of pigs infected with tapeworm cysts. We hope that when we inspect the pigs at the end of the project, after 10 months, we will see this number greatly reduced.”
Pour on dips for mange that is prevalent and weight-bands, which are used for accurately estimating the weight of the animals for safe dosing of medication, were also distributed to all pig owners. It is a highlight for Dr Peter, CEO of Afrivet, that the team members felt both humbled and proud to be involved in such a ground-breaking intervention, the results of which, we believe, will lead to an improved quality of life for the people of Upper Gxulu village.