Zoonosis: Chagas Disease. Describe the connection between human, animal, and ecosystem health as it relates to this disease. Explain how is globalization affecting the transmission rates and rates of this disease globally?
Chagas is a type of zoonotic disease caused by the protozoan parasite Trypanosoma cruzi. The disease, also referred to as the American trypanosomiasis, was named after Carlos Chaga, the Brazilian doctor who discovered it in 1909. The disease is prevalent in America, mainly Latin America, where poverty is widespread. Approximately 8 million people are living with the disease in rural Mexico, Central and South America, and the surrounding regions. The increasing health problems and mortality rate associated with the disease has called for the implementations of vector control programs in an effort to eliminate the spread of the infections.
What Causes Chagas Disease?
The Chagas disease is transmitted to humans and animals by the blood-sucking triatome bugs specifically found in America. The triatome vector or the “kissing bug” becomes infected with T-cruzi and passes it to humans and animals by biting and laying their feces on the fresh. Triatomine bugs are mainly found in houses made from mud, adobe, straw palm, and thatch. The bugs will hide during the day and emerge at night to suck blood when the inhabitants are asleep. People can also get infected with the disease through blood transfusion, organ transplantation, congenital transmission such as from mother to child, consumption of uncooked food contaminated with infected feces from triatomine bugs, and accidental laboratory exposure. A person cannot become infected with Chagas through casual contact with an infected person like flu and other airborne infections.
Symptoms of Chagas Disease
Many people, approximately 70-90% who are infected are asymptomatic carriers of the parasite. Mortality rates from Chagas disease are also relatively low. However, 30% of the asymptomatic carriers develop acute symptoms, including swelling of the eyelid when the eye becomes infected with the T-cruzi. Other acute symptoms may include body aches, rash, loss of appetite, vomiting, diarrhea, fatigue, fever, and headaches. Chronic complications resulting from Chagas disease have cardiac complications and gastrointestinal problems.
Chagas was initially a Latin American disease, but through urbanization and globalization, the disease has spread to cities and other countries worldwide. However, infection from the triatomine bug to humans is still rare in the urban setting. Most transmission occurs through blood transfusion and other secondary modes of transmission. The free movement of people around the world, particularly regions that receive huge populations and immigrants from the Latin countries, precipitated the spread of the Chagas disease. Thirty years later, the movement of people from the endemic Latin areas to Europe and North America increased the disease’s prevalence significantly. By 1990, infection rates had risen to around 30 million worldwide.
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