The World Food Safety Day is celebrated every June 7 since 2018.
This year’s World Food Safety Day was celebrated on Tuesday under the theme “Safer food, better health”.
“Food safety is everyone’s business, if it is not safe, it’s not food,” these are the UN slogans for the day.
This calls attention to the fact that we all have a role to play in ensuring the food we eat is safe, right from the farmer producing the food, the food processors, transporters and traders, consumers to the government agencies mandated with food safety along the food supply chain. The slogans are also a call for action to all to do something about the food safety debate.
Why the food safety debate?
Food is necessary for life and if not properly handled from production to consumption/farm to fork or glass to grass, can be an agent of diseases and death to the consumers. Contribution to the risks related to the safety of food can occur at any level of the production chain.
A case in point is the zoonotic parasite, the pig tapeworm of man.
There had been an increase in the consumption of pork in various urban areas in Kenya in the recent past. This has resulted in mushrooming of “pork centres” particularly in Nairobi and its environs, including Kiambu and Thika towns.
Whereas pork is a good source of animal protein, improper handling of the live animal and the meat may cause serious negative health and economic impact on the population.
Among diseases of importance as far as consumption of pork is concerned is the pork tapeworm of man.
The pork tapeworm infection in man, referred to as taeniasis, is caused by the parasite Taenia solium. The zoonotic parasite causes an intestinal infection with tapeworms in humans and a neurological disorder such as epilepsy.
Humans get infected when they eat raw or undercooked, infected pork that contains the parasite larvae, leading to development of the adult tapeworms in the small intestines. Adult tapeworm can grow up to a length of 2-3 metres and live for 25 years in the small intestines
Man can also be affected by eating raw vegetables and using water contaminated with eggs of the tapeworm.
The adult worm release segments containing eggs, which are passed in faeces that contaminate water, soils and vegetation. Nearly 250,000 eggs are passed daily through human faeces and to the environment, and the cycle continues.
Human can also get infected by ingesting the tapeworm eggs leading to development of cysts (fluid filled sac) in the muscles, eyes and brain. This may lead to the neurocysticercosis characterised by among other signs, epilepsy and blindness.
The disease is more prevalent where there are no latrines and human beings defaecate in the bushes, and it is also prevalent where pigs are left to scavenge in dump sites
Pigs get infected when they feed on food contaminated with the eggs of the tapeworms. In the pigs, these eggs hatch in the small intestines to a larval stage called onchosphere.
The larvae penetrate the wall of the small intestines and enter the blood circulation. They travel through the blood stream to the muscles of the pig such as the heart, cheek, tongue, forearm, foreleg and the diaphragm.
The infection with adult tapeworm in human may cause severe abdominal pain feeling as intensive hunger pangs. This is thought to be caused by hooks on the head of the tapeworm. Infected human beings will shed mature segments full of eggs which can be seen in stool.
The development of the larval stage (cysts) in the brain will lead to neurocysticercosis manifested by severe headaches, epilepsy, paralysis and sometimes coma. If the cyst develops in the eyes they may cause blindness.
There are normally no clinical signs in the pigs, the cysts are seen in the live pig on examination of the tongue where cysts may be detected in the underside of the tongue. The cysts may also be detected during meat inspection in the various muscles.
Prevention and control of the T.solium is aimed at disruption of the lifecycle, this can be achieved through various ways such as avoiding open defaecation through proper use of toilet, washing of hands, vegetables and fruits with clean water.
In addition to regular deworming of infected adults and children, proper meat inspection and condemnation of infected carcasses and organs, proper cooking of pork, ensuring pigs are housed to prevent scavenging and feeding pigs with clean feed.
Dr Joyce Thaiya, Dr Evans Muthuma and Dr Suleiman Olesarioyo are from the Directorate of Veterinary Services