First of all, as another post already talked about how to prevent getting parasites while traveling, this post will focused more on how to prevent getting parasites that you are susceptible to acquire in developed countries (link to Can I acquire parasites in developed countries?). Of course, these prevention means are directly linked to the known modes of transmission of parasitic diseases.
Foodborne parasitic diseases are usually easily preventable. For example, parasites present in meat like pork and beef, such as some helminths species like Trichinella spiralis or Taenia, are easily preventable by cooking enough the meat before eating it and by avoiding to eat raw meat. Furthermore, getting parasites that are usually present in fish, such as Diphyllobothrium, can be easily prevented by eating well-cooked fish or by freezing it before eating it raw in some dishes like sushi or ceviche. It is noteworthy that some parasites’ eggs are able to resist to the temperature used in our home freezer and that it is consequently better to buy fish that had been frozen quickly after being caught in lower-temperature industrial freezer. This method guaranteed that the fish is fresh and that it had been to the temperature appropriate to kill all kind of parasites. Finally, it is really important to wash fresh food, like fruit and vegetables, before eating it to get rid of any parasite coming from a contamination with animal’s or human’s faeces. It is especially true with more risky imported food, but also with homegrown food.
Some precautions must also be taken to avoid getting some frequent waterborne parasitic diseases in developed countries, such as the gastrointestinal illnesses cryptosporidiosis caused by the parasite Cryptosporidium and giardiasis caused by Giardia intestinalis. Drinking untreated waters, such as from lakes or rivers, and bathing in recreational waters with not enough chlorine should be avoided. It is also very important to teach children not to drink untreated water or recreational water, as they are more at risk to have this type of behaviour.
Even though the majority of parasites are not usually transmitted sexually, there is one notable exception. The sexually transmitted parasite Trichomonas vaginalis is considered as one of the most frequent protozoan parasites in developed countries. However, this parasitic infection is easily preventable by wearing a condom during sexual intercourse. This mean of prevention is very important, especially because men are mostly asymptomatic and they usually do not know that they have been infected with this parasite.
Other precautions, such as wearing gloves while gardening or changing the cat’s litter box must also be taken, especially for people with weakened immune system or for pregnant women. These precautions prevent getting a parasite from contaminated animal faeces that could have been in contact with the soil, such as Toxoplasma gondii. This parasite is usually asymptomatic for the healthy human being, but can have severe consequences on the unborn child when acquired by pregnant women or on people with weakened immune system.
Furthermore, even though this type of infection is quite rare, it is possible to acquire Acanthamoeba keratitis from contaminated contact lenses. Having a good hygiene with contact lenses and their container according to the manufacturer’s specifications can easily prevent this disease. It is also very important to wear contact lenses only as recommended by their provider.
Finally, even though vector-borne parasitic diseases are less frequent in developed countries when compared with tropical countries, some parasites are therefore susceptible to be acquired by the bite of an insect vector, especially in warmer zones such as the South of the United States and the South of Europe. For example, the parasite Leishmania, transmitted by the bite of the sandfly, is known to cause opportunistic infections in people living with AIDS in Southern Europe. Furthermore, tick bites can also transmit the protozoan parasites Babesia, responsible for a disease called babesiosis, in the United States and in Europe.
Source: Centers for Disease Control and Prevention.