World Chagas Disease Day is marked on April 14 to increase awareness about the potentially life-threatening infectious disease that affects around seven million people worldwide.
Chagas disease, also known as American trypanosomiasis, is caused by the parasite Trypanosoma cruzi. The parasite usually spreads through triatomine bugs, or “kissing bugs,” when they swallow blood from an infected animal.
The disease was earlier confined to continental rural areas of the Region of the Americas but it is now seen in the U.S., Canada and many of the European, African, Eastern Mediterranean and Western Pacific countries.
If failed to identify early, the disease can cause serious problems in the heart and digestive systems and can turn fatal. It is estimated that around 10,000 people die every year worldwide from the disease.
Transmission:
Through food or beverages contaminated with T. cruzi
From infected mother to newborn during pregnancy and childbirth
Blood transfusion or an organ transplant from an infected person
Accidental exposures while working in labs
From infected wild animals, such as raccoons and opossums
Early signs of the silent disease
Chagas disease is also known as a silent or silenced disease as its symptoms are absent or mild in the initial acute phase of the infection that lasts for about two months.
In the acute stage, patients may suffer mild symptoms such as:
Fever and fatigue
Rash
Body pain and headaches
Eyelid swelling, swollen glands
Loss of appetite
Nausea, diarrhea or vomiting
Enlargement of liver or spleen
Most of these symptoms usually go away on their own. But if left untreated, the infection advances to the chronic stage.
Symptoms in the chronic stage include cardiac complications such as irregular heartbeat, heart failure and cardiac arrest. Patients also develop gastrointestinal complications such as difficulty in swallowing, stomach pain or constipation due to an enlarged esophagus or colon.
Treatment
The disease is usually treated with benznidazole or nifurtimox, and both medicines are effective in curing the condition if administered soon after the onset of the acute phase. However, the treatment becomes less effective when the medications are given long after the start of symptoms. Adverse reactions to the treatment are frequent in older people. These medicines are however not advisable for pregnant women or people with kidney or liver failure.
How to prevent
There are currently no vaccines for Chagas disease.
Eradicating the infection is not feasible as T. cruzi parasites are widely seen in wild animals. Prevention efforts focus on the elimination of transmission to humans and early detection of infection.
In Latin America, disease prevention aims at vector control. Spraying insecticides in areas around the houses helps to control bugs that carry the parasite.
Effective screening before blood transfusion and organ transplant helps in preventing transmission.
Screening of newborns and other children of infected mothers helps in the early detection of the disease.
Incorporating good hygiene practices in the preparation, transportation, storage and consumption prevents transmission through contaminated food.
Antiparasitic treatment for children and women of childbearing age helps in prevention.
Triatoma brasiliensis (Triatominae), kissing bug, vector of Trypanosoma cruzi, the etological agent of Chagas disease. Zezinho68/Wikimedia Commons