Chagas disease is prevalent mainly among the world's poor, and the number of infected people worldwide, mainly in Latin America, is estimated to be 600 to 700 million.About 3% of the population in El Salvador, which has many mud-walled houses and is home to many vector insects, is said to be affected.In the early stages of infection, most of them are asymptomatic, and if they develop serious heart disease after becoming chronic, there is no cure and they die. It is one of the "neglected tropical diseases" designated by the WHO, and investigations and studies on the risk of infection by vector insects have been inadequate.

　The research team investigated 2018 houses across El Salvador from September 9 to November 2020, and as a result, collected 11 vector insects (assassin bugs) in 311 houses, observed their droppings under a microscope, Detection of the pathogen (Trypanosoma cruzi) was performed.DNA was extracted from fecal samples that were confirmed to be infected, and a PCR diagnosis was performed.

　The study found a 34% home invasion rate for vector insects and a 10% infection rate for pathogens.Although the pathogen is ubiquitous throughout El Salvador, 14 out of 5 regions (departments) have high prevalence.

　The results of this research will enable continuous and selective vector control, especially in highly infected areas, and are expected to be utilized for efficient allocation of resources for vector control by local governments.In the future, we will further clarify the pathogenesis of Chagas disease and clarify the relationship between the genomic background of the parasite and the onset of the disease.

Paper information:[Infectious Diseases of Poverty] Re-emerging threat of Trypanosoma cruzi vector transmission in El Salvador, update from 2018 to 2020