Aedes hensilli as a Potential Vector of Chikungunya and Zika Viruses

Abstract

An epidemic of Zika virus (ZIKV) illness that occurred in July 2007 on Yap Island in the Federated States of Micronesia prompted entomological studies to identify both the primary vector(s) involved in transmission and the ecological parameters contributing to the outbreak. Larval and pupal surveys were performed to identify the major containers serving as oviposition habitat for the likely vector(s). Adult mosquitoes were also collected by backpack aspiration, light trap, and gravid traps at select sites around the capital city. The predominant species found on the island was Aedes (Stegomyia) hensilli. No virus isolates were obtained from the adult field material collected, nor did any of the immature mosquitoes that were allowed to emerge to adulthood contain viable virus or nucleic acid. Therefore, laboratory studies of the probable vector, Ae. hensilli, were undertaken to determine the likelihood of this species serving as a vector for Zika virus and other arboviruses. Infection rates of up to 86%, 62%, and 20% and dissemination rates of 23%, 80%, and 17% for Zika, chikungunya, and dengue-2 viruses respectively, were found supporting the possibility that this species served as a vector during the Zika outbreak and that it could play a role in transmitting other medically important arboviruses.

Concurrent outbreaks of dengue, chikungunya and Zika virus infections – an unprecedented epidemic wave of mosquito-borne viruses in the Pacific 2012–2014

“…These species have been incriminated in DENV transmission on epidemiological and/or experimental (laboratory infections) grounds. Several of them are confirmed or strongly suspected vectors of CHIKV and Zika viruses [21]. Thirdly, large population mobility and airline travel facilitate the spread [22].…”

Zika virus: what do we know about the viral structure, mechanisms of transmission, and neurological outcomes?

“…This notion was questioned as other modes of transmission were identified. Many species of the genus Aedes can spread the virus in different geographic regions in natural and urban environments (33) (34) (39) (40) (41) , however, their potential as vectors is variable and only 20-50% of infected females carry virus particles in the saliva in some species (42) (43) .…”

“…Other viable Flavivirus viruses in the blood bags have also been reported (46) (47) (48) . Simultaneous circulation of two or more arboviruses (43) in many countries highlights the necessity for proper screening of blood samples for these viruses. Genetic material of three different viruses has been detected in samples from a single patient in Latin America (39) (49) and Zika virus RNA and viable particles were detected in blood samples from asymptomatic donors in French Polynesia (50) .…”

Outbreak of Zika Virus Infection, Chiapas State, Mexico, 2015, and First Confirmed Transmission byAedes aegyptiMosquitoes in the Americas

“…Culex species have not been associated with ZIKV transmission during outbreaks in Yap [3], Gabon [4], or French Polynesia [2]. However, other Aedes species have been implicated in urban transmission in Gabon [4] and Oceania [2,3,10].…”