Taxonomic integrative and phylogenetic identification of the first recorded Triatoma rubrofasciata in Zhangzhou, Fujian Province and Maoming, Guangdong Province, China

Abstract

Background: Most species of Triatominae live exclusively in Latin America. However, one species, Triatoma rubrofasciata, has been recorded in the Americas as well as in various port areas in Africa and Asia. An increasing number of T. rubrofasciata have been reported in southern China in recent years. However, the origin of this invasive insect vector in China remains unknown, therefore, accurate identification and phylogenetic analysis of the bugs are urgently needed.Methods: A total of seven triatomine insect specimens were found and collected from Maoming City, Guangdong Province, China (GDMM) and Zhangzhou City, Fujian Province, China (FJZZ), respectively. The obtained insect vector specimens were observed under a dissecting microscope for morphological classification and then the genomic DNA was extracted, and the 16S ribosomal RNA (rRNA), 28S rRNA as well as cytochrome oxidase subunit I (COI) genes of the species were amplified and sequenced. Subsequently, molecular phylogenetic analyses based on multiple alignments of the above genes were conducted in order to identify the species and determine the phylogenetic origin approximation accurately. Results:The triatomine insects collected from GDMM and FJZZ were identified as Triatoma rubrofasciata using morphological and genetic analyses. All of the Chinese T. rubrofasciata captured in FJZZ, GDMM and other localities in southern China, together with a Vietnamese and Brazilian strain, formed a new, cohesive clade. T. rubrofasciata in GDMM and FJZZ are likely derived from strains found in Vietnam or Brazil. Conclusions: To the best of our knowledge, this is the first record of the invasive insect T. rubrofasciata, which is likely derived from strains native to Vietnam or Brazil, in both Maoming City, Guangdong Province and Zhangzhou City, Fujian Province of China. A comparison of the DNA sequences of the 16 s rRNA, 28 s rRNA and COI genes confirmed the specific identification of T. rubrofasciata, and its potential origin in China is based on the phylogenetic analyses undertaken in this study. More targeted interventions and improved entomological surveillance are urgently needed to control the spread of this haematophagous insect in China.

Biological attributes of the kissing bug Triatoma rubrofasciata from Vietnam

“…Our data with cytb sequences showed a high genetic similarity suggesting a common and recent origin of the Asian (Vietnam, China) and American populations (Brazil). Similar results were recently shown using other nuclear ( 28S rDNA) and mitochondrial ( 16S rDNA and cox 1 ) markers [8]. Furthermore, the low genetic variation between Tryp.…”

“…The individuals collected were identified as T. rubrofasciata following the morphological keys traditionally applied for triatomine species identification [1] with external characteristics similar to individuals from China [6–8].…”

“…Triatomine bugs (891 eggs, 394 nymphs in all stages and 559 adults) were caught in both urban and rural areas from seven provinces in central Vietnam. The morphological and chromatic characteristics in the individuals collected were the same as those described in specimens from southern China [6–8]. Most of them were collected in two cities, Da Nang and Quy Nhon, during July 2014 to July 2016.…”

“…In other South American countries such as French Guiana or Venezuela, T. rubrofasciata has not been found in the last 20 years [5]. On the contrary, the presence of T. rubrofasciata in Asia has increased in recent years, having been reported in China [6–8], Vietnam [3], India [9] and Sri Lanka [10]. In Vietnam, a national survey during the period 2010–2012 showed that T. rubrofasciata is found in at least 21 provinces, involving large cities such as Hanoi and Ho Chi Minh [3].…”

The spreading of parasites by human migratory activities

“…The tropicopolitan distribution range of the triatomine species T. rubrofasciata (Table 4), a vector for T. cruzi in Latin America, can be only explained by recent spreading events. DNA sequence analyses using nuclear and mitochondrial marker genes showed high similarity between New World and Old World specimens indicating a common and recent origin of Asian and American populations of T. rubrofasciata [110,111]. The close association of T. rubrofasciata with domestic rats (especially R. rattus) suggests that the triatomine bug was spread around the globe by international shipping during the sixteenth to eighteenth centuries [112].…”