Chagas Trivia & Facts
Medical Realities
Which of the following is false?
A) Both African and American trypanosomiasis are caused by a parasitic nematode infection.
B) Chagas’ disease AKA American trypanosomiasis is transmitted by the kissing bug.
C) An estimated six to eight million people in Central and South America are infected with Chagas disease, with 700,000 new cases in 1990 but only 28,000 new cases in 2023.
D) Thirty percent of patients infected with Chagas disease will develop cardiac damage. 12,000 people die each year.
Source- Pan American Health Organization
Answer A is incorrect. Both African and American trypanosomiasis are caused by a parasitic protozoan infection. African trypanosomiasis AKA African sleeping sickness is transmitted by the tsetse fly. Protozoan infections also cause malaria, amoebic dysentery, and babesiosis.
The Kissing Bug: A Hidden Danger
Why is it called the kissing bug?
The kissing bug has earned its name due to its habit of biting its human hosts on the face, often near the lips or mouth, during the night. This nocturnal behavior, combined with its preference for biting exposed skin, has led to the moniker "kissing bug."
Where are kissing bugs common?
Kissing bugs are primarily found in the Americas, particularly in Central and South America. However, their range has been expanding, and cases have been reported in the southern United States, including Texas, California, and Arizona. These insects thrive in rural areas with poor housing conditions, where they can find shelter in cracks and crevices in walls and roofs.
Understanding Chagas Disease and Its Impact
The dangers of Chagas disease
Chagas disease, also known as American trypanosomiasis, is a parasitic infection transmitted by the kissing bug. The parasite, Trypanosoma cruzi, is found in the insect's feces and is transmitted to humans through a bite.
While many people infected with Chagas disease initially experience no symptoms or only mild ones, the infection can lead to serious health problems, including heart disease, digestive disorders, and neurological complications. In severe cases, Chagas disease can be fatal.
Two Stages
Chagas disease has two stages. The first stage, called the acute phase, happens shortly after infection. The second stage, known as the chronic phase, occurs over a long time. In both stages, some people might not feel sick at all, while others can have serious health problems.
Acute phase: This early stage happens in the first weeks or months after getting infected. Symptoms are often mild or not there at all and can include:
Fever
Feeling tired
Body aches
Headache
Enlarged glands (enlarged lymph nodes)
Rash
Loss of appetite
Diarrhea
Vomiting
Eyelid swelling (Romaña's sign). A symptom of Chagas disease is Romaña's sign—when the eyelid swells up. This happens when the Trypanosoma cruzi parasite gets into the eyelid, usually by accidentally rubbing the bug feces (poop) into your eye or into a bug bite near your eye.
Chronic phase: This stage can last many years or even a lifetime. Most people have no symptoms during this time. However, about 20 – 30% of those infected develop serious problems. These include:
Heart issues, such as an enlarged heart, heart failure, altered heart rate or rhythm, or sudden death.
Digestive problems, such as an enlarged esophagus or colon, leading to trouble eating or going to the bathroom.
Clinical Testing and Diagnosis for Chagas Disease
Acute Chagas disease can be identified by spotting parasites in blood using microscopy.
For chronic Chagas, look for specific antibodies against the parasite.
Since 2006, the FDA has approved tests for screening blood donations for specific antibodies against the T. cruzi parasite.
Diagnosing Acute Chagas Infections:
Healthcare providers diagnose acute Chagas infections by identifying trypomastigotes in blood using microscopy.
Parasite levels in the blood decrease rapidly within a few months and become undetectable by most diagnostic methods during the chronic phase.
Diagnosing Chronic Chagas Disease:
For chronic Chagas disease, healthcare providers detect antibodies against the parasite using serologic tests.
Testing protocol:
No single test is sufficiently sensitive and specific for diagnosis.
Use two or more tests that detect antibodies to different antigens.
Common techniques include enzyme-linked immunosorbent assay (ELISA) and immunofluorescent antibody test (IFA).
Treatment and prevention
As healthcare professionals, it's crucial to be aware of the subtle signs and symptoms of Chagas disease, especially in regions where the kissing bug is prevalent. Early detection and treatment can prevent serious complications and improve patient outcomes.
If diagnosed early, Chagas disease can be treated with antiparasitic medications. However, once the infection has progressed, treatment options are limited.
Preventing Chagas disease involves avoiding contact with kissing bugs. This can be achieved by using insecticide-treated bed nets, improving housing conditions, and wearing long sleeves and pants when sleeping in areas where kissing bugs are prevalent.
Antiparasitic treatment
Antiparasitic treatment works best when started early but can be used at any stage of the disease. In the United States, there are two treatments available:
Benznidazole is FDA approved for use in children 2 – 12 years of age and is commercially available at http://www.benznidazoletablets.com.
Lampit® (nifurtimox) is FDA approved for treatment of children from birth to age younger than 18 years and is commercially available for pharmacies to purchase from several drug wholesalers.
Source: CDC September 4, 2024 and National Center for Emerging and Zoonotic Infectious Diseases (NCEZID)
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