Your Guide to
Neglected Tropical Diseases

Chagas disease, prevalent in Latin America, is a potentially life-threatening illness caused by Trypanosoma cruzi and typically spreads through contact with infected insects. Most infections occur in childhood and remain asymptomatic for years or decades, which is why it is often referred to as the “silent killer.”

The disease has two phases: an acute phase (first weeks or months after infection), often presenting with mild or no symptoms, and a chronic phase that can last a lifetime. Approximately 20%-30% of chronically infected people develop serious heart problems including heart failure and arrhythmia, while 10% develop digestive complications.

The disease causes significant disability in patients, increases the rate of sudden death among people in their prime working years, and leads to loss of work capacity, contributing to poverty cycles in affected populations. Early diagnosis during asymptomatic periods and appropriate treatment can significantly slow disease progression, reduce complications, and prevent long-term disability.

Triatomine bugs (also called kissing bugs) are blood-sucking insects that transmit Chagas disease. These bugs hide during the day in the walls and roofs of rural houses and come out at night to bite sleeping people and animals, leaving infected droppings on their skin. The droppings can get into the bite wound, eyes, or mouth when they scratch the itchy bite site-this is how the parasite enters the body.

The disease also spreads through contaminated food or drinks (particularly unpasteurized juices), blood transfusion, organ transplantation, mother-to-child transmission, and laboratory accidents. There are over 100 mammal species that can carry the parasite.

Geographic scope:

• Endemic in about 20 countries across North, Central, and South America.
• Detected in 44 countries worldwide due to migration, including the United States, Canada, Europe, Western Pacific, Japan, Australia, and parts of Africa.
• Primarily affects rural areas with poor housing conditions.

Population affected:

• 6-7 million people infected worldwide.
• Approximately 75 million people at risk of infection.
• 30,000-40,000 new cases annually, with approximately 12,000 deaths per year.

Two medications are used to treat Chagas disease: benznidazole and nifurtimox. Treatment can cure the disease if started soon after infection, but it becomes less effective with increasing duration of infection. Treatment is recommended for all new infections, all children up to age 18, and adults up to age 50 who do not have heart damage. Both medications frequently cause side effects, including skin rashes, stomach problems, and nerve-related symptoms, leading to early treatment termination in 15%-40% of patients.

Prevention focuses on vector control through insecticide spraying, which has successfully interrupted transmission in several countries. Other measures include improving housing quality, using insecticide-treated bed nets, avoiding unpasteurized juices and unwashed produce, screening blood and organ donations, and testing pregnant women and newborns. There are currently no vaccines available for Chagas disease.