Fig. 1: Intestinal symbiotic bacteria act as essential contributors to the differential vector competence of Ae. albopictus and Ae. aegypti for ZIKV transmission.
From: Gut symbiont-derived sphingosine modulates vector competence in Aedes mosquitoes
a,b Susceptibility of lab-adapted Ae. aegypti (UGAL/Rockefeller strain) and Ae. albopictus (Jiangsu strain) to ZIKV infection via blood-feeding or microinjection. Three- to four-day-old adult mosquitoes were fed with mouse blood containing 1.0 × 105 FFU/mL ZIKV. A 1000 FFU ZIKV dose was microinjected into the thorax of 3-day-old adult females. Virus RNA levels in mosquitoes (a; n = 24 for Ae. aegypti via blood-feeding; n = 23 for Ae. albopictus via blood-feeding; n = 14 for Ae. aegypti via microinjection; n = 15 for Ae. albopictus via microinjection) were measured using qPCR at 7 d post infection. Virus titers in saliva (b; n = 15 for Ae. aegypti via blood-feeding, Ae. albopictus via blood-feeding, Ae. aegypti via microinjection, and Ae. albopictus via microinjection) were detected using focus-forming assay at 10 d post infection. c,d ZIKV levels in lab-adapted Ae. aegypti (UGAL/Rockefeller strain) (c; n = 26 for Con.; n = 24 for Antibiotic-treatment), lab-adapted Ae. albopictus (Jiangsu strain) (c; n = 24 for both Con. and Antibiotic-treatment), field-derived Ae. aegypti (Haikou strain) (d; n = 18 for Con.; n = 22 for Antibiotic-treatment), and field-derived Ae. albopictus (Haikou strain) (d; n = 24 for both Con. and Antibiotic-treatment) were affected by symbiotic bacteria. Fifty mosquitoes, with or without antibiotic treatment, were infected with ZIKV. The viral loads were examined using qPCR at 7 d post infection. The top of each column shows the number of infected mosquitoes relative to the total number of mosquitoes. Each point represents one mosquito or one saliva sample. Percentages represent the rate of mosquito infection. Data are shown as mean ± SEM. The experiments were repeated twice with similar results. Statistical significance was determined using a two-sided Mann–Whitney test. *P < 0.05, **P < 0.01. ns: not significant. Source data are provided as a Source Data file.
