It can take up to six months to obtain the result. Xenodiagnosis involves feeding the blood to triatomine insects, then examining their feces for the parasite 30 to 60 days later. These methods are not routinely used, as they are slow and have low sensitivity. Prevention
Efforts to prevent Chagas disease have largely focused on vector control to limit exposure to triatomine bugs. Insecticide-spraying programs have been the mainstay of vector control, consisting of spraying homes and the surrounding areas with residual insecticides. This was originally done with organochlorine, organophosphate, and carbamate insecticides, which were supplanted in the 1980s with pyrethroids. These programs have drastically reduced transmission in Brazil and Chile, and eliminated major vectors from certain regions: Triatoma infestans from Brazil, Chile, Uruguay, and parts of Peru and Paraguay, as well as Rhodnius prolixus from Central America. Vector control in some regions has been hindered by the development of insecticide resistance among triatomine bugs. In response, vector control programs have implemented alternative insecticides (e.g. fenitrothion and bendiocarb in Argentina and Bolivia), treatment of domesticated animals (which are also fed on by triatomine bugs) with pesticides, pesticide-impregnated paints, and other experimental approaches. In areas with triatomine bugs, transmission of T. cruzi can be prevented by sleeping under bed nets and by housing improvements that prevent triatomine bugs from colonizing houses.Blood transfusion was formerly the second-most common mode of transmission for Chagas disease.
Enlargement of the esophagus or colon are the most common digestive issues. Those with enlarged esophagus often experience pain (odynophagia) or trouble swallowing (dysphagia), acid reflux, cough, and weight loss. Individuals with enlarged colon often experience constipation, and may develop severe blockage of the intestine or its blood supply. Up to 10% of chronically infected individuals develop nerve damage that can result in numbness and altered reflexes or movement. While chronic disease typically develops over decades, some individuals with Chagas disease (less than 10%) progress to heart damage directly after acute disease.Signs and symptoms differ for people infected with T. cruzi through less common routes. People infected through ingestion of parasites tend to develop severe disease within three weeks of consumption, with symptoms including fever, vomiting, shortness of breath, cough, and pain in the chest, abdomen, and muscles. Those infected congenitally typically have few to no symptoms, but can have mild non-specific symptoms, or severe symptoms such as jaundice, respiratory distress, and heart problems. People infected through organ transplant or blood transfusion tend to have symptoms similar to those of vector-borne disease, but the symptoms may not manifest for anywhere from a week to five months. Chronically infected individuals who become immunosuppressed due to HIV infection can have particularly severe and distinct disease, most commonly characterized by inflammation in the brain and surrounding tissue or brain abscesses.