Occurrence of synanthropic triatomines (Hemiptera: Reduviidae) in the Federal District of Brazil

Abstract

This retrospective analysis considered the number of adults and nymphs of each species collected and infected in both intradomicile and peridomicile. Results: A total of 754 triatomines were collected in 252 reported domiciles. Panstrongylus megistus was the most frequent species (65%), followed by T. pseudomaculata (14%). Of the 309 examined insects, only 3 (1%) specimens of P. megistus were infected with flagellates morphologically similar to Trypanosoma cruzi. The spatial occurrence indicated a higher diversity of triatomines and frequency of T. sordida in rural areas. Moreover, there was a predominance of P. megistus in urban areas. The number of records of P. megistus in the rainy season was two times higher than that during the dry season. The largest number of triatomines was collected in November. Conclusions: The presence of P. megistus specimens infected with trypanosomes in domiciles, shows the potential risk of human infection in DF. Thus, it is essential to continue entomological surveillance, intensifying it in the rainy season and in regions of greater occurrence. Keywords: Chagas disease control. Entomological surveillance. Synanthropic triatomines. Federal District. Brazil. triatomines. Furthermore, the invasion and/or colonization of infected triatomines from wild ecotopes may represent the risk of vectorial transmission with the installation of peridomiciliary and domiciliary cycles of T. cruzi 6,7 . In this context, the objective of this paper is to analyze the spatial and temporal occurrence of triatomine species collected in DF, as well as their indices of natural infection with trypanosomes to direct actions of entomological surveillance of Chagas disease coordinated by SES-DF. RESUMO 72 METHODS RESULTS Maeda MH et al -Occurrence of triatomines in DF Study areaThe Federal District of Brazil is geographically located between the parallels 15º30' and 16º03' south latitude, and between meridians 47°25' and 48°12' west longitude, in Central Brazil, one of the highest areas of the region, the Central Plateau. According to 2010 Census results, the population comprises 2,563,963 people in an area of 5,787,784km 2 divided into 30 administrative regions 8 . The area is filled with plateaus over 1,000m in altitude. The average annual rainfall is around 1,600mm, and the average annual temperature ranges between 18°C and 20°C with two distinct seasons, the dry season from May to September and the rainy season from October to April, the latter season with the highest temperature records 9 . Triatomine collection and natural infectionThe insects were collected in intradomiciliary and peridomiciliary environments by residents and then taken to the PITs. Each PIT receives a kit with materials for insect storage, a notepad to keep notes containing the address and location of collection, and tweezers for the handling of specimens.After notification, the SES-DF public health agents did active searches in these houses and their annexes. The materials used for triatomine collection were metal tweezers and fl...

Climatic factors influencing triatomine occurrence in Central-West Brazil

“…Data on the occurrence of triatomine species in domiciliary environments between 1975-1983 were also taken into account (Silveira et al 1984), as were data from other studies (Silva & Lustosa 1993, Carcavallo et al 1999, 2002, Carcavallo & Jurberg 2000, Oliveira & Silva 2007, Almeida et al 2008, Gurgel-Gonçalves & Silva 2009, Gurgel-Gonçalves et al 2012b, Maeda et al 2012, Obara et al 2012). In addition, records of triatomines in the collections of Rodolfo Carcavallo and Herman Lent at the National and International Reference Laboratory on Triatomine Taxonomy at the Oswaldo Cruz Institute, Oswaldo Cruz Foundation, were analysed.…”

“…Nevertheless, acute cases of human disease caused by transmission via native triatomine species are still being registered (MS/SVS 2012). Triatomines continue to infest homes in a number of states in Brazil (Oliveira & Silva 2007, Almeida et al 2008, Villela et al 2009, Gurgel-Gonçalves et al 2010, Silva et al 2011, 2012, Maeda et al 2012). …”

Synanthropic triatomines as potential vectors of Trypanosoma cruzi in Central Brazil

“…In our dataset, the two administrative regions with the most reported triatomines in the Federal District were Vicente Pires and Park Way, whereas Maeda et al 6 reported most bugs from the more rural Planaltina and Sobradinho. This suggests that the number of triatomines, particularly P. megistus, found in urbanized environments may have increased over the last few years.…”

“…In 2002-2010, and using methods comparable to ours, 754 bugs were caught in 20 administrative regions 6 . This suggests that sylvatic foci of synanthropic triatomines persisted in the Federal District, with the bugs (especially P. megistus) regularly invading and at times colonizing human habitats.…”

“…Thaís Tâmara Castro Minuzzi-Souza [1] , Nadjar Nitz [2] , César Augusto Cuba Cuba [1] , Marcelo Santalucia [3] , Monique Knox [4] , Luciana Hagström [2] , Camilla Bernardes Furtado [1] , Tamires Emanuele Vital [2] , Marcos Takashi Obara [1] , Mariana Machado Hecht [2] and Rodrigo Gurgel-Gonçalves 5,6 .…”