30% of them infected with the protozoan that causes Chagas disease teams from the Endemic Diseases Oversight Office (SUCEN) have found 135 insects in the municipalities of Greater São Paulo that are carriers of the protozoan that causes Chagas disease While there are no cases of the disease reported in humans yet laboratory analyses at SUCEN indicate that the captured insects had been feeding on the blood of humans and animals “We need to be careful to avoid transmission to people,” warns biologist Rubens Antonio da Silva a scientific researcher and technical coordinator for the Chagas disease control program at the oversight agency When a kissing bug was identified in 2015 in Pirapora do Bom Jesus Silva and his team thought they might be simply sporadic events That conclusion fell apart when they received calls from residents of Taboão da Serra in the following years and also received notifications from Carapicuíba and neighborhoods in the western districts of São Paulo Juquitiba and Santana de Parnaíba were added to the list of municipalities reporting kissing bugs researchers identified colonies with 57 insects living in possum nests under the tile roofs of three houses in a subdivision surrounded by forest 47% of the kissing bugs were infected with Trypanosoma cruzi females with eggs were found under the mattress on which the residents slept While on the rise for the first time in the São Paulo Metropolitan Region the kissing bug population has fallen in other parts of the state The total number of insects captured has decreased from about 6,000 in 2007 to about 2,000 in 2018 as Silva describes in an article published in April 2019 in the Brazilian Journal of Health Review the state of São Paulo reported only one new case of Chagas disease in 2016 and two in 2017 During the same two years the number of new cases went from 20 to 320 in Pará and from 3 to 24 in Amapá states with the majority of new case reports Brazil received international certification from the World Health Organization (WHO) for practically eliminating the kissing bug Triatoma infestans the principal species transmitting the disease which today is restricted to regions of Bahia and Rio Grande do Sul as a result of the high infection rates prevalent through the mid-twentieth century it’s estimated that 1.2 million to 4.6 million people in Brazil have the chronic form of Chagas disease responsible for approximately 6,000 deaths per year which affects about 30% of people with the parasite according to the WHO Currently the species of kissing bug that causes the most concern is Panstrongylus megistus since it is capable of living in both forests and domestic spaces Megistus has a brown body with red spots and is 2.5 to 4 centimeters in length the insect may enter homes through open doors or windows cruzi by feeding on the blood of animals that harbor it—without themselves developing the disease—called natural reservoirs megistus in the metropolitan region of São Paulo have been sparse 15 specimens were captured in the city of São Paulo Only two insects were examined: one collected in 2011 in Jabaquara but the specimen collected in 2014 in Sacomã This is according to a survey by biologist Walter Ceretti Junior published in July 2018 in the Revista do Instituto de Medicina Tropical de São Paulo rodents and possums approach houses for shelter and food,” says Ceretti Júnior “The possibility of parasite transmission leaving the sylvatic [wildlife] cycle and expanding into urban areas is at the very least worrying,” says epidemiologist Guilherme Werneck a professor at the Federal University of Rio de Janeiro (UFRJ) megistus in areas close to forests in four neighborhoods in the western districts of São Paulo: Jardim Amaralina Examining the locations of kissing bug reports in recent years they concluded that the insects may be on the move taking advantage of parks and forest corridors starting from the region between the Régis Bittencourt and Raposo Tavares highways “If in fact there is a territorial expansion of the carrier insects the situation tends to worsen,” Silva observes He believes that if the hypothesis is correct then since the insects reproduce more intensely in the summer residents of northern neighborhoods such as Tucuruvi will likely find the insects nearby or inside their homes by late 2019 SUCEN’s action plan includes communicating with the residents of Cotia The parasite is transmitted mainly through food or beverages contaminated with feces from kissing bugs “We have to avoid letting them form colonies 565 adults and 1,183 kissing bug nymphs of the species Rhodnius neglectus were collected from dozens of palm trees in the streets and squares of the northwestern city of Araçatuba in São Paulo State He states that although these kissing bugs weren’t infected the concern is that a contaminated possum might climb the palm trees in search of parrot eggs and transmit the parasite to the insects “The identification of kissing bugs in urban areas reinforces the need to warn of the risks of transmission to humans,” says biologist José Eduardo Tolezano director of the Center for Parasitology at the Adolfo Lutz Institute (IAL) today accounts for 9% of the human cases recorded in Brazil by the Ministry of Health the means by which the parasite was transmitted is not identified Currently the leading cause is oral transmission (72%) through the consumption of food or drink containing feces from insects contaminated with the parasite a study by the Tropical Medicine Foundation reported ten cases of people who presented with the initial symptoms of Chagas disease—fever and weakness—after drinking acai juice contaminated with T a transmission event of still uncertain origin was reported In a group of 77 people who attended a religious retreat during Holy Week in Ibimirim possibly contracted from contaminated food or drink Their treatment was initiated with benznidazole which is effective in controlling the acute phase of the disease but has strong side effects such as allergic skin reactions © Revista Pesquisa FAPESP - All rights reserved.