Despite the nutritional benefits and value for money offered by pork, in many parts of the world, particularly in developing countries, it is still viewed with suspicion.

A friend of mine from Latin America, who eats ham and bacon, will not eat “pork”, because it comes from pigs. In developed countries, most consumers judge pork in exactly the same way as they do other meats, but in some parts of the world, it can present a very real danger.

According to the World Health Organization (WHO), cystericosis is emerging as a serious public health and agricultural problem in many poorer countries of Africa, Asia and Latin America. It is considered to be the most common parasitic infection of the human nervous system, and the most frequent preventable cause of epilepsy in the developing world.

WHO estimates that cystericosis affects some 50 million people worldwide and, in endemic areas, causes some 50,000 deaths.

Hurdle crossed

However, an end could now be in sight for the damage caused by the tapeworm Taenia solium, and the impact that this has on the reputation of pig meat, as a vaccine has eliminated transmission of the parasite in pigs in a field trial in Africa.

Attempts to control neurocysticercosis by treating infected humans have had limited success, as the parasite can remain in the pig population of endemic areas. Treating pigs with anthelmintics is effective in killing the parasite, but does not prevent re-infection. Additionally, parasites killed by drugs leave unsightly lesions in meat, making it unsuitable for sale.

Vaccinating pigs, however, offers a relatively inexpensive approach to controlling the parasite’s spread and indirectly reducing the number of cases of human diseases. TSOL18 is one such vaccine that has proven extremely effective in protecting pigs against experimental exposure to the parasite.

In a study funded by the human and animal health charity The Wellcome Trust, a pilot field trial of TSOL18 was conducted in the far north of Cameroon – an area where pigs are naturally exposed to the faeces of humans infected with the parasite.

Piglets were vaccinated at two to three months of age and given booster immunization after four weeks and again four months later. At the time of the second immunization, the pigs were also treated with drugs to kill any parasites that may have established themselves prior to vaccination. The pigs were then allowed to roam free around the village, as is typical of local farming practices.

At the end of the study, around one in five of the untreated pigs were infected with the parasite, most of them with thousands of parasites. However, the trial team found that none of the vaccinated animals had become infected. Additionally, any lesions caused by dying parasites following treatment had disappeated over the nine-month period prior to slaughter, improving the quality of meat from vaccinated animals.

Professor Lightowlers, who led the research, commented that the procedure used was relatively simple and sustainable, and so has genuine potential to from the basis for widespread control of the parasite’s transmission. He added that a significant hurdle had been crossed meaning that the end for neurocysticercosis was well and truly insight.

This is great news for all those living in areas that are affected by the parasite, and also means that unfavourable attitudes towards pork could start to decrease too, and my friend from Latin America, might start to include roast pork in his menu as an alternative to bacon and ham!