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Parasitic Infections

What is a Parasitic Infection?

A parasitic infection is an infection caused by a parasite, a small organism that lives in another organism called the host, and survives from its food supply. While some parasites are harmless, others cause disease or infection. Some common parasitic infections include:

  • Trichomoniasis
  • Giardiasis
  • Cryptosporidiosis
  • Toxoplasmosis

What Causes Parasitic Infections?

Parasitic infection is caused by three types of organisms: helminths, protozoa, and ectoparasites. The infection is spread through:

  • Drinking or eating contaminated water or food
  • Waste, soil, and blood
  • Sexual contact
  • Insects that act as a vector, or carrier, of the disease

What are the Symptoms of Parasitic Infections?

Symptoms vary depending on the type of organism.

  • Trichomoniasis is a sexually transmitted infection caused by the parasite Trichomonas vaginalis. Most people who have trichomoniasis have no symptoms. It may cause a burning sensation when urinating or after ejaculation in men, and a foul-smelling vaginal discharge and genital redness, with itching and burning, in women.
  • Giardiasis is an infection caused by the parasite Giardia lamblia. Giardiasis may cause diarrhea, greasy stools, fatigue, nausea, excessive gas, and dehydration.
  • Cryptosporidiosis is an infection caused by the parasite Cryptosporidium. It may cause stomach cramps, diarrhea, weight loss, nausea, vomiting, dehydration, and fever.
  • Toxoplasmosis may cause flu-like symptoms which include swollen glands and body aches or pains that can last for over a month, as well as fever, fatigue, and sore throat.

How are Parasitic Infections Diagnosed?

Your doctor diagnoses parasitic infections with the help of the following:

  • Blood testing
  • Stool testing
  • An endoscopy or colonoscopy
  • X-rays, magnetic resonance imaging (MRI), or computerized axial tomography (CAT)

What are the Treatments for Parasitic Infections?

Treatment plans can vary, depending on the type of parasitic infection.

  • Trichomoniasis is usually treated with antibiotics. You may be given one large dose or a longer course to take for a week. Repeat infection is very common, so you will need to be re-tested after about 3 months.
  • Giardiasis may not require any treatment if there are mild or absent symptoms and may go away on its own. However, anti-parasitic drugs may be recommended by some doctors. For severe symptoms or for prolonged cases your doctor may prescribe antibiotics.
  • For cryptosporidiosis, treatment options include anti-motility agents to relieve diarrhea, oral or IV fluids with electrolyte replacement to prevent dehydration, and anti-parasitic drugs and antiretroviral therapies.
  • If you are diagnosed with toxoplasmosis but you are healthy and not pregnant, you probably won’t need any treatment other than conservative management. Only pregnant women or those with a compromised immune system may need medical treatment to avoid severe complications. For people with HIV or AIDS or for pregnant women whose babies have not been affected, your doctor may prescribe antibiotics.

How are Parasitic Infections Prevented?

You can prevent or lower your risk of getting a parasitic infection via the following steps:

  • Washing your hands thoroughly before making food or eating
  • Avoiding drinking unfiltered water
  • Washing and peeling all fresh fruits and vegetables thoroughly before consuming
  • Practicing safe sex such as using condoms
  • Purifying all pond, stream, lake, well, or river water before drinking. You can purify water by boiling, treating it with iodine, or by filtering
  • Washing your hands thoroughly after scooping or cleaning cat litter