Background Recent reports reveal the presence of Wolbachia in Ae. aegypti . Our study presents additional support for Wolbachia infection in Ae. aegypti by screening field-collected adult mosquitoes using two Wolbachia -specific molecular makers. Methods A total of 672 Ae. aegypti adult mosquitoes were collected from May 2014 to January 2015 in Metropolitan Manila. Each individual sample was processed and screened for the presence of Wolbachia by selected markers, Wolbachia -specific 16S rDNA and its surface protein ( wsp ), under optimized PCR conditions and sequenced. Results Totals of 113 (16.8%) and 89 (13.2%) individual mosquito samples were determined to be infected with Wolbachia using the wsp and 16S rDNA markers, respectively. The Ae. aegpyti wsp sample sequences were similar or identical to five known Wolbachia strains belonging to supergroups A and B while the majority of 16S rDNA sample sequences were similar to strains belonging to supergroup B. Overall, 80 (11.90%) individual mosquito samples showed positive amplifications in both markers and 69% showed congruence in supergroup identification (supergroup B). Conclusions By utilizing two Wolbachia -specific molecular makers, our study demonstrated the presence of Wolbachia from individual Ae. aegypti samples. Our results showed a low Wolbachia infection rate and inferred the detected strains belong to either supergroups A and B. Electronic supplementary material The online version of this article (10.1186/s13071-019-3629-y) contains supplementary material, which is available to authorized users.

11It was the impression from past literature that Wolbachia is not naturally found in Ae. aegypti. 12 However, there are have been reports that recently reveals the presence of this endosymbiont 13 in this mosquito vector. With this, our study presents additional support of Wolbachia 14 infection in Ae. aegypti by screening field-collected adult mosquitoes using Wolbachia-15 specific 16S rDNA and its surface protein (wsp) makers under optimized PCR conditions. 16 From a total of 672 Ae. aegpyti adult mosquito samples collected in Metropolitan Manila, 17 Philippines, 113 (16.8%) and 89 (13.2%) individual mosquito samples were determined to 18 be Wolbachia infected using the wsp and 16S rDNA markers, respectively. The Ae. aegpyti 19 wsp sample sequences were similar or identical to five known Wolbachia strains belonging 20 to supergroups A or B while majority of 16S rDNA sample sequences were similar to strains 21 belonging to supergroup B. Overall, 80 (11.90%) individual mosquito samples revealed to 22 show positive amplifications in both markers and 69.0% showed congruence in supergroup 23 identification (supergroup B). Our findings illustrate that the infection status of Wolbachia 24 in Ae. aegypti may appear common than previously recognized. 26Mosquitoes are considered to be medically important insects because of their capacity 27 to carry notable human disease pathogens 1 . Among the known mosquito vectors, Aedes 28 aegypti is an efficient and dangerous mosquito vector because of its ability to carry 29 significant arboviral diseases such as Dengue, Chikungunya, Yellow Fever and Zika 2,3 . 30Despite the development of vaccines, these arboviral diseases are considered to be the leading 31 cause of global disease burden 4 and thus, targeting the mosquito vector is deemed to be the 32 primary control and prevention. A considerable number of vector control strategies had been 33 implemented, but the disease burden continues to increase. Novel and newer approaches are 34 being developed that shows promising outcomes in vector and disease control and one of 35 which is the utilization of the intracellular bacterial endosymbiont, Wolbachia 7-9 . 36Wolbachia is a naturally occurring endosymbiont which can be maternally inherited 37 and cause different reproductive alterations in its host to increase their transmission to the 38 next generation 10-12 . In insects, it is estimated to be naturally present in 60-65% of known 39 species 13 . As to date, there are 17 identified major clades or supergroups (A-Q) where a 40 majority are known to infect arthropods such as insects, arachnids, and crustaceans 14 . The 41 pathogenic effects of Wolbachia in its host are well-studied and determined to cause sperm-42 egg incompatibility, parthenogenesis, cytoplasmic incompatibility, and feminization 11,15 . 43 Therefore, utilizing these effects towards medically-important mosquito vectors, such as Ae. 44 aegypti, has taken great research strides in the past two decades. The discovery of a virulent 45 Wolbachi...