[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]
J Med Entomol. 2019 Jul 6. pii: tjz110. doi: 10.1093/jme/tjz110. [Epub ahead of print]
Vertical Transmission of Zika Virus (Flaviviridae, Flavivirus) in Amazonian Aedes aegypti (Diptera: Culicidae) Delays Egg Hatching and Larval Development of Progeny.
Chaves BA1,2, Junior ABV1, Silveira KRD3, Paz ADC1, Vaz EBDC1, Araujo RGP3, Rodrigues NB3, Campolina TB3, Orfano ADS3, Nacif-Pimenta R3, Villegas LEM3, Melo FF4, Silva BM5, Monteiro WM1,2, Guerra MDGVB1,2, Lacerda MVG1,6, Norris DE7, Secundino NFC3, Pimenta PFP1,3.
Author information: 1 Tropical Medicine Foundation Dr. Heitor Vieira Dourado, Manaus, Amazonas, Brazil. 2 Amazonas State University, Minas Gerais, Belo Horizonte, Brazil. 3 Laboratory of Medical Entomology, Rene Rachou Research Institute – FIOCRUZ, Minas Gerais, Belo Horizonte, Brazil. 4 Multidisciplinary Health Institute, Federal University of Bahia, Bahia, Brazil. 5 Department of Biological Sciences, Federal University of Ouro Preto, Minas Gerais, Ouro Preto, Brazil. 6 Leonidas and Maria Deane Research institute – FIOCRUZ, Amazonas, Brazil. 7 The Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD.
Zika virus (ZIKV) has emerged as a globally important arbovirus and has been reported from all states of Brazil. The virus is primarily transmitted to humans through the bite of an infective Aedes aegypti (Linnaeus, 1762) or Aedes albopictus (Skuse, 1895). However, it is important to know if ZIKV transmission also occurs from Ae. aegypti through infected eggs to her offspring. Therefore, a ZIKV and dengue virus (DENV) free colony was established from eggs collected in Manaus and maintained until the third-fourth generation in order to conduct ZIKV vertical transmission (VT) experiments which used an infectious bloodmeal as the route of virus exposure. The eggs from ZIKV-infected females were allowed to hatch. The resulting F1 progeny (larvae, pupae, and adults) were quantitative polymerase chain reaction (qPCR) assayed for ZIKV. The viability of ZIKV vertically transmitted to F1 progeny was evaluated by cultivation in C6/36 cells. The effects of ZIKV on immature development of Ae. aegypti was assessed and compared with noninfected mosquitoes. AmazonianAe. aegypti were highly susceptible to ZIKV infection (96.7%), and viable virus passed to their progeny via VT. Moreover, eggs from the ZIKV-infected mosquitoes had a significantly lower hatch rate and the slowest hatching. In addition, the larval development period was slower when compared to noninfected, control mosquitoes. This is the first study to illustrate VT initiated by oral infection of the parental population by using mosquitoes, which originated from the field and a ZIKV strain that is naturally circulating in-country. Additionally, this study suggests that ZIKV present in the Ae. aegypti can modify the mosquito life cycle. The data reported here suggest that VT of ZIKV to progeny from naturally infected females may have a critical epidemiological role in the dissemination and maintenance of the virus circulating in the vector.
© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America.
KEYWORDS: Aedes aegypti ; Zika virus; fitness cost; vertical transmission
PMID: 31278737 DOI: 10.1093/jme/tjz110
Keywords: Flavivirus; Zika Virus; Aedes aegypti.