Comparative analysis of the susceptibility of Aedes aegypti and Japanese Aedes albopictus to all dengue virus serotypes

Daisuke Kobayashi; Izumi Kai; Astri Nur Faizah; Meng Ling Moi; Shigeru Tajima; Tomohiko Takasaki; Toshinori Sasaki; Haruhiko Isawa

doi:10.1186/s41182-023-00553-5

Comparative analysis of the susceptibility of Aedes aegypti and Japanese Aedes albopictus to all dengue virus serotypes

Trop Med Health. 2023 Nov 2;51(1):61. doi: 10.1186/s41182-023-00553-5.

Authors

Daisuke Kobayashi^#^{1

2}, Izumi Kai^#^{3

4}, Astri Nur Faizah³, Meng Ling Moi^{5

6}, Shigeru Tajima⁵, Tomohiko Takasaki^{5

7}, Toshinori Sasaki³, Haruhiko Isawa³

Affiliations

¹ Department of Medical Entomology, National Institute of Infectious Diseases, Tokyo, Japan. dkoba@niid.go.jp.
² Management Department of Biosafety, Laboratory Animal, and Pathogen Bank, National Institute of Infectious Diseases, Tokyo, Japan. dkoba@niid.go.jp.
³ Department of Medical Entomology, National Institute of Infectious Diseases, Tokyo, Japan.
⁴ Graduate School of Agriculture, Meiji University, Kanagawa, Japan.
⁵ Department of Virology I, National Institute of Infectious Diseases, Tokyo, Japan.
⁶ Department of Developmental Medical Sciences, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
⁷ BML, Inc., Tokyo, Japan.

^# Contributed equally.

Abstract

Background: Dengue fever, caused by the dengue virus (DENV), is the most common viral infection transmitted by Aedes mosquitoes (mainly Ae. aegypti and Ae. albopictus) worldwide. Aedes aegypti is not currently established in Japan, and Ae. albopictus is the primary vector mosquito for DENV in the country, but knowledge of its viral susceptibility is limited. Therefore, we aimed to clarify the status of DENV susceptibility by comparing the infection and dissemination dynamics of Japanese Ae. albopictus to all known DENV serotypes with those of Ae. aegypti.

Methods: After propagation of each DENV serotype in Vero cells, the culture supernatants were mixed with defibrinated rabbit blood and adenosine triphosphate, and the mixture was artificially blood-sucked by two colonies of Ae. albopictus from Japan and one colony of Ae. aegypti from a dengue-endemic country (Vietnam). After 14 days of sucking, the mosquito body was divided into two parts (thorax/abdomen and head/wings/legs) and total RNA was extracted from each sample. DENV RNA was detected in these extracted RNA samples using a quantitative RT-PCR method specific for each DENV serotype, and infection and dissemination rates were analyzed.

Results: The Japanese Ae. albopictus colonies were susceptible to all DENV serotypes. Its infection and dissemination rates were significantly lower than those of Ae. aegypti. However, the number of DENV RNA copies in Ae. albopictus was almost not significantly different from that in Ae. aegypti. Furthermore, Japanese Ae. albopictus differed widely in their susceptibility to each DENV serotype.

Conclusions: In Japanese Ae. albopictus, once DENV overcame the midgut infection barrier, the efficiency of subsequent propagation and dissemination of the virus in the mosquito body was comparable to that of Ae. aegypti. Based on the results of this study and previous dengue outbreak trends, Ae. albopictus is predicted to be highly compatible with DENV-1, suggesting that this serotype poses a high risk for future epidemics in Japan.

Keywords: Aedes; Aedes aegypti; Aedes albopictus; Asian tiger mosquito; DENV; DENV-1; Dengue; Japan; Mosquito; Susceptibility.