Chagas Disease: What is it and how to prevent it?

Friday April 14th was World Chagas Day. I had never heard of Chagas and wanted to find out more about it.

What is Chagas disease?

Chagas disease, also known as American trypanosomiasis, is a potentially life-threatening illness caused by the parasite Trypanosoma cruzi. The parasite spreads the pathogen through insect vectors that are found only in the Americas, among which the blood-sucking triatomine bug (also known as the ‘kissing bug’)is the most common one: it takes a blood meal and releases trypomastigotes (the pathogen) in its faeces near the site of the bite wound, allowing the parasite enter the host’s body.  


What are some symptoms of Chagas disease?

Acute Chagas disease occurs immediately after infection. This phase of infection is usually mild or asymptomatic, there may be fever or swelling around the site of inoculation (where the parasite enters the skin), sometimes, although very rare, it can lead to severe inflammation of the heart muscle or the brain and lining around the brain. 

Other symptoms of this phase include:

  • Fatigue.
  • Rash.
  • Body aches.
  • Eyelid swelling.
  • Headache.
  • Loss of appetite.

A prolonged asymptomatic form of disease would occur after the acute phase. During this time, most people are unaware of their infection. Many people may remain asymptomatic for life and never develop Chagas-related symptoms. However, it is estimated that 20 -30% of infected people, especially those who have suppressed immune systems due to AIDs, will develop severe and sometimes life threatening medical problems over the course of their lives. 

Complications of chronic Chagas disease may include:

  • Heart rhythm abnormalities that can cause sudden death;
  • A dilated heart that doesn’t pump blood well; and
  • A dilated oesophagus or colon, leading to difficulties with eating or passing stool.

How to prevent it?

Although Chagas disease is the most prevalent in Latin America, you should bear in mind that the migration of infected people can transport the disease to non-endemic countries. It is proved that improved housing and spraying insecticide inside housing to eliminate the bugs has significantly decreased the spread of Chagas disease. Screening of blood donations for Chagas is another important public health tool to help prevent spreading the disease through blood transfusions. Early detection and treatment of new cases, including mother-to-baby (congenital) cases, will also help reduce the burden of disease.

What should I do if I think I have Chagas disease?

You should discuss your concerns with your healthcare provider, who will examine you and ask you questions (for example, about your health and where you have lived). Chagas disease is diagnosed by blood tests. If you have Chagas disease, you should have a heart tracing test (electrocardiogram), even if you feel fine. You might be referred to a specialist for more tests and treatment.