Yan Sun's research while affiliated with Sun Yat-Sen University and other places

The sterile insect technique is based on the overflooding of a target population with released sterile males inducing sterility in the wild female population. It has proven to be effective against several insect pest species of agricultural and veterinary importance and is under development for Aedes mosquitoes. Here, we show that the release of sterile males at high sterile male to wild female ratios may also impact the target female population through mating harassment. Under laboratory conditions, male to female ratios above 50 to 1 reduce the longevity of female Aedes mosquitoes by reducing their feeding success. Under controlled conditions, blood uptake of females from an artificial host or from a mouse and biting rates on humans are also reduced. Finally, in a field trial conducted in a 1.17 ha area in China, the female biting rate is reduced by 80%, concurrent to a reduction of female mosquito density of 40% due to the swarming of males around humans attempting to mate with the female mosquitoes. This suggests that the sterile insect technique does not only suppress mosquito vector populations through the induction of sterility, but may also reduce disease transmission due to increased female mortality and lower host contact.

The sterile insect technique (SIT) is based on the overflooding of a target population with released sterile males inducing sterility in the wild female population. The SIT has proven to be effective against several insect pest species of agricultural and veterinary importance and is under development for Aedes mosquitoes. Here, we show that the release of sterile males in high sterile male to wild female ratios may also impact the target female population through mating harassment. Under laboratory conditions, male to female ratios above 50 to 1 reduced the longevity of female Aedes mosquitoes by reducing their feeding success. Under semi-field conditions, blood uptake of females from an artificial host and biting rates on humans were also strongly reduced. Finally, in a field SIT trial conducted in a 1.17 ha area in China, the female biting rate was reduced by 80%, concurrent to a reduction of female mosquito density of 40% due to the swarming of males around humans attempting to mate with the female mosquitoes. This suggests that the SIT does not only suppress mosquito vector populations through the induction of sterility, but might also reduce disease transmission due to increased female mortality and lower host contact.

BACKGROUND The sterile insect technique (SIT) is a green and species‐specific insect pest control technique that suppresses target populations by releasing factory‐reared, radiosterilized males into the wild. Once released, it is important to be able to distinguish the released males from the wild males for monitoring purposes. Several methods to mark the sterile males exist. However, most have limitations due to monetary, process efficiency, or insect quality. Aedes albopictus is naturally infected with Wolbachia at a high prevalence, therefore the elimination of Wolbachia can serve as a biomarker to distinguish factory‐reared male mosquitoes from wild conspecifics. RESULTS In this study, a Wolbachia‐free Ae. albopictus GT strain was developed and its fitness evaluated, which was found to be comparable to the wild GUA strain. In addition, GT male mosquitoes were irradiated at the adult stage and a dose of 20 Gy or more induced over 99% sterility. Moreover, a dose of 30 Gy (almost completely sterilizing male and female mosquitoes) had limited effects on the mating competitiveness of GT males and the vector competence of GT females, respectively. However, radiation reduced mosquito longevity, regardless of sex. CONCLUSION Our results indicate that the Ae. albopictus GT strain can be distinguished from wild mosquitoes based on Wolbachia status and shows similar fitness, radio‐sensitivity and arbovirus susceptibility to the GUA strain, indicating that it is feasible to use the GT strain to suppress Ae. albopictus populations for SIT programmes. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

The geographic boundaries of arboviruses continue to expand, posing a major health threat to millions of people around the world. This expansion is related to the availability of effective vectors and suitable habitats. Armigeres subalbatus (Coquillett, 1898), a common and neglected species, is of increasing interest given its potential vector capacity for Zika virus. However, potential distribution patterns and the underlying driving factors of Ar. subalbatus remain unknown. In the current study, detailed maps of their potential distributions were developed under both the current as well as future climate change scenarios (SSP126 and SSP585) based on CMIP6 data, employing the MaxEnt model. The results showed that the distribution of the Ar. subalbatus was mainly affected by temperature. Mean diurnal range was the strongest predictor in shaping the distribution of Ar. subalbatus, with an 85.2% contribution rate. By the 2050s and 2070s, Ar. subalbatus will have a broader potential distribution across China. There are two suitable expansion types under climate change in the 2050s and 2070s. The first type is continuous distribution expansion, and the second type is sporadic distribution expansion. Our comprehensive analysis of Ar. subalbatus’s suitable distribution areas shifts under climate change and provides useful and insightful information for developing management strategies for future arboviruses.