First records of Triatoma rubrofasciata(De Geer,1773)(Hemiptera,Reduviidae)in Foshan,Guangdong Province,Southern China

Background:Triatomines,also known as kissing bugs,which are found throughout the world and especially in Latin America,are well known natural vectors that transmit American trypanosomiasis,also called Chagas disease.In China,the presence of two species of Triatoma(Triatoma rubrofasciata and T.sinica)was recorded in the past.Due to the growing population and the increasing risk of the global spread of Chagas disease,triatomines became a potential public health nuisance,and in 2016,we started monitoring triatomine activities in southern China.Methods:Triatomine specimens were collected by the National Institute of Parasitic Diseases,Chinese Center for Disease Control and Prevention,and identified by their morphological characteristics under a dissecting microscope.In addition to morphological analysis,the genomic DNA of the specimens was extracted,and the mitochondrial 16S rRNA,the cytochrome b(CytB)gene and the nuclear ribosomal 28S rRNA gene were PCRamplified to analyze and confirm the species genetically.Results:One female adult insect and one male adult insect were collected in a dwelling in the rural area of Shunde County,Foshan City,Guangdong Province,China(22°42′44.63″N,113°08′45.34″E).The results from the morphological and genetic analyses indicated that these triatomines were T.rubrofasciata.Conclusions:This is the first time that the occurrence of T.rubrofasciata has been confirmed in Foshan City,Guangdong Province in southern China.Further studies are needed to reach a clearer understanding of the ecology of this species of triatomine,since it has been found to be naturally infected by Trypanosoma cruzi and T.conorhini and there is evidence of its domiciliation capabilities.

Triatoma williami in intradomiciliary environments of urban areas in Mato Grosso State, Brazil: domiciliation process of a wild species?

BackgroundTriatomines in Latin America are natural Chagas disease (ChD) vectors. Triatomine domiciliation is one of the main factors increasing the occurrence risk of this disease in humans. There are 66 triatomine species in Brazil, with three genera of significant epidemiological importance—Panstrongylus, Rhodnius, and Triatoma. Among the Triatoma species, Triatoma williami, a wild species, has been reported in Goiás, Mato Grosso, and Mato Grosso do Sul. In the Barra do Garças, Mato Grosso, the invasion by triatomines has been reported, with T. williami being the most common species. This study aimed to survey triatomine fauna and determine the Trypanosoma cruzi natural infection rates in triatomines in the urban area of Barra do Garças, Mato Grosso, Brazil.MethodsTriatomine specimens were sampled by passive surveillance or active search by agents combating endemic diseases from 2019 to 2020. A parasitological feces diagnosis was performed to detect the presence of T. cruzi after the specimens were identified. Concerning T. cruzi identification, molecular diagnosis and genetic sequencing were performed to determine the strain, also called discrete typing units (DTUs).ResultsThe 211 triatomines were collected, distributed in specimens of T. williami (84.4%), P. geniculatus (3.3%), P. diasi (1.4%), and R. neglectus (10.9%). Two colonies of T. williami were found through morphological analyses. These insects were sampled inside domiciles in an urban area neighboring Jardim Pitaluga (15° 51′57.7″ N, 052° 16′ 04.5 E). The records were sampled in September 2019 and January 2021. The rate of natural infection by T. cruzi was 39.4%. Two T. williami specimens from the sampled colonies were positive for the T. cruzi strain DTU IV.ConclusionsThis is the first time that T. williami has been confirmed in an urban area of Barra do Garças, Mato Grosso, Brazil. Further studies are needed for a clearer understanding of the ecology of this species for prevention and control mechanisms since its sampled specimens had a high rate of natural infection by T. cruzi.