Do your parents have that one embarrassing story from your childhood that they like to tell your friends and relatives during gatherings? Mine do, and the story goes like this, apparently when I was young, I used to like digging up earthworms and eating them, gross I know, but for a very long time in my childhood I had tapeworms (even more embarrassing I know) and coming to think of it, I was eating more than just the earthworms.
Tapeworms and other worms are parasites associated with poor sanitation and hygiene. An infection with these worms is known as helminthosis and this post is basically about our role and that of the animals in the transmission of worms. Some worms can be transmitted from animals such as dogs, cats, pigs, fish, cows etc to man. The most common route of infection is through the oral route although some worms can penetrate the skin. Below are some of the worms that we can get from animals we interact with on the daily.
For those of you who like going to the beach and feeling the sand under your feet, that act alone puts you at a risk of acquiring hookworms. Ancylostoma braziliense is a hookworm whose larval stages can penetrate through the skin into the body. They are found in the sand especially at the beach. These hookworms cause irritation at the site of entry and may cause a skin condition known as “creeping eruptions”.
Dog and cat lovers are also not spared, the dog tapeworm known as Dipylidium caninum is transmitted from dogs to man through faeces. Children can get infected when playing with their dogs and accidentally by eating with contaminated hands. Proper disposal of dog faeces is an important method of controlling the spread.
Taeniasis is an intestinal infection caused by adult tapeworms.Three types of tapeworms cause taeniasis in humans, Taenia solium , Taenia saginata and Taenia asiatica. Only T. solium is of importance. T. solium taeniasis is acquired by eating tapeworm larval cysts in undercooked infected pork. Human tapeworm carriers excrete the eggs in faeces and contaminate the pastures. Ingested T. solium eggs then develop to larvae in various organs of the human body. When they enter the central nervous system they can cause neurological symptons (neurocysticercosis), including epileptic seizures.
Ascariasis is another common infection caused by Ascaris lumbricoides in man. The Ascaris worm is quite long measuring upto 35cm in length. The worms actually look like spaghetti and they are transmitted through eating contaminated food and water. The worms can cause obstruction of the intestines due to their size and length. In children, the worms can cause retarded growth. Maintaining strict hygiene practices can reduce infection. The Ascaris lumbricoides is closely related to the Ascaris suum which affects pigs but can also affect man.
And finally, for the fish lovers, you can get a tapeworm knowns as Diphyllobothrium latum if you eat raw or undercooked fish.
In summary, sanitary improvement, meat inspection, improvements in livestock sanitation on the farm, improved standards of living, and progress in personal hygiene are among the barriers that are cutting the lifeline between parasites and their human hosts.