Opportunistic Parasites and their Prevention

Opportunistic parasites are an emerging issue these days. Usually these parasites do not cause disease in healthy people. The reason is that healthy people have immune system strong enough to prevent the disease occurrence.

Opportunistic Parasites and their Prevention

But, whenever the immune system is compromised, these parasites find an opportunity to cause disease. This is the reason they are termed opportunistic parasites. Commonly these organisms are commensals and non-pathogenic. There are various reasons for compromised immune system like aging, malnutrition, stress, organ transplant, chemotherapy, AIDS and others.

Opportunistic parasitic infections are an emerging issue these days due to increased evidence of AIDS. According to an estimate in 2015, over 42 million people were infected with HIV virus. Some opportunistic parasitic infections include Giardiasis, Cryptosporiosis, Microsporidiosis, Toxoplasmosis, Strongyloidiasis etc. When these parasites find opportunity, they attack the host causing disease.

Most commonly, these parasites are associated with gastro-intestinal disorders. However, some may also produce severe conditions like hydrocephalus by toxoplasmosis. Opportunistic parasitic infections that occur during the span of AIDS are the most common cause of death. The reason is that AIDS targets the immune system of the person leading to low CD4 cell count.

CD4 cells are actually the T-lymphocytes which have a vital role in the immune response against pathogens. They are also known as T-helper cells as they are responsible for sending signals to other cell types of the immune system. Thus, depleted CD4 cells count makes a person vulnerable to attack by a number of parasites including the opportunistic ones also.

So, the question arises, how can we prevent or control their occurrence? There are different measures and practices which can be adopted to control their occurrence. All these efforts are aimed at breaking the life cycle of these parasites. Some strategies for control are:

  • Cook the food properly. Eat hygienic food. Many parasitic infections are acquired from eating raw, unhygienic and improperly cooked food. For example, toxoplasmosis is acquired by man through ingestion of oocysts-containing meat.
  • Take care of personal hygiene. Wash your hands frequently.
  • Adopt proper safety protocol while dealing with the patients. This is because many infections can be contracted from other humans. For instance, giardiasis and cryptosporidium are waterborne diseases and may be transmitted through contact with other persons as they may carry their cysts or oocysts attached to their bodies.
  • Take care of animals. The animals are also a major source of parasites. So, deworm them and vaccinate them. For example, cats are the definitive hosts for toxoplasma and shed oocysts in their feces.
  • Avoid using contaminated needles. Use disposable apparatus. Properly sterilize the surgical equipment.
  • Administration of immuno-modulatory antibodies to boost the immune system of patient also avoids opportunistic infections.


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    Article Via : Dr. Muhammad Salman, Dr. Rao Zahid Abbas, Sehar Shah, Faiza Naeem, Faiza

    Corresponding Author

    Dr. Muhammad Salman (msalmanhameed@gmail.com)

By Muhammad Salman

Veterinarian. Currently studying in M.Phil Parasitolgy.