Background: Anopheles stephensiis native to Southeast Asia and the Arabian Peninsula and has emerged as an effective and invasive malaria vector. Since invasion was reported in Djibouti in 2012, the global invasion range ofAn. stephensihas been expanding, and its high adaptability to the environment and the ongoing development of drug resistance have created new challenges for malaria control. Climate change is an important factor affecting the distribution and transfer of species, and understanding the distribution ofAn. stephensiis an important part of malaria control measures, including vector control.Methods: In this study, we collected existing distribution data forAn. stephensi, and based on the SSP1-2.6 future climate data, we used the Biomod2 package in R Studio through the use of multiple different model methods such as maximum entropy models (MAXENT) and random forest (RF) in this study to map the predicted globalAn. stephensiclimatically suitable areas.Results: According to the predictions of this study, some areas where there are no current records ofAn. stephensi, showed significant areas of climatically suitable forAn. stephensi. In addition, the global climatically suitability areas forAn. stephensiare expanding with global climate change, with some areas changing from unsuitable to suitable, suggesting a greater risk of invasion ofAn. stephensiin these areas, with the attendant possibility of a resurgence of malaria, as has been the case in Djibouti.Conclusions: This study provides evidence for the possible invasion and expansion ofAn. stephensiand serves as a reference for the optimization of targeted monitoring and control strategies for this malaria vector in potential invasion risk areas.

Invasive alien species are a growing threat to natural systems, the economy, and human health. Active surveillance and responses that readily suppress newly established colonies are effective actions to mitigate the noxious consequences of biological invasions. Aedes (Hulecoeteomyia) koreicus (Edwards), a mosquito species native to East Asia, has spread to parts of Europe and Central Asia since 2008. In the last decade, Ae. koreicus has been shown to be a competent vector for chikungunya virus and Dirofilaria immitis. However, information about the current and potential distribution of Ae. koreicus is limited. Therefore, to understand the changes in their global distribution and to contribute to the monitoring and control of Ae. koreicus, in this study, the MaxEnt model was used to predict and analyze the current suitable distribution area of Ae. koreicus in the world to provide effective information.

Rodents are carriers and hosts of numerous zoonotic pathogens, analysing the diversity of viruses and bacteria carried by rodents is important for predicting and reducing the risk of future outbreaks of zoonotic diseases. Heilongjiang is a border province in China with rich ecological resources. In this study, we characterized the zoonotic microbiota (viruses and bacteria) in wild rodents. Sixty-seven rodents representing two species (20 Apodemus peninsulae; 47 Myodes rufocanus) were collected in Hengdaohezi Town, Heilongjiang Province, China. Metagenomic sequencing was employed to characterize pathogen carriage in these reservoirs. The sequencing results showed that the annotated viruses covered 21 viral families, including family Arenaviridae and family Hantaviridae. The annotated bacteria cover 1051 bacterial genera, including genus Salmonella and genus Yersinia. Results of de novo assembly of extracted viral sequences using Megahit showed that 154 contigs were assembled from these two hosts, and 110 of these contigs were mapped to 19 viruses from eight families, including Rat arterivirus1, Amur virus and Lassa mammarenavirus, these results can provide a certain reference for the monitoring and control of rodents in Heilongjiang Province.

Aedes aegypti is the primary vector of mosquito-borne viruses and threatens human health globally. To monitor temporal changes in the population genetics of Ae. aegypti in Yunnan Province, we collected specimens from five sites between 2016 and 2018 and analyzed them at nine microsatellite loci and the mitochondrial cox I gene. Genetic diversity in these populations rose initially and then declined over the study period. The inbreeding coefficient shifted from a heterozygous state toward moderate inbreeding. Ten cox I haplotypes were identified, with haplotypes H06 and H09 prevalent across regions, while other haplotypes were limited to specific regions or years. Clustering analyses demonstrated significant population shifts of Ae. aegypti across the five sampling sites from 2016 to 2018. AMOVA analysis of all Ae. aegypti populations indicated that from 2016 to 2018, the main source of variation was predominantly among individuals, accounting for 76.43%, 65.15%, and 80.36%, respectively. Population dispersion patterns across locations initially increased and then decreased over time. Therefore, continuous monitoring is essential, and particular attention should be paid to intra-provincial spread, especially between port and urban areas.

The overuse of chemical insecticides highlights the urgent need for novel vector control strategies. Insect-specific viruses (ISVs), such as the cell-fusing agent virus (CFAV), have shown potential to block arbovirus transmission by inhibiting viral replication in mosquitoes. However, the effects of CFAV beyond its natural host, Aedes aegypti, remain largely unexplored. In this study, we established a CFAV infection model in Aedes albopictus, a major vector for Zika virus (ZIKV), via intrathoracic injection. Stable infection was achieved, with viral loads reaching up to 10⁷ copies per mosquito by day 10 post-injection. Nevertheless, high post-injection mortality (median survival: 3 days) was observed, which we attribute primarily to mechanical injury. No evidence of vertical transmission of CFAV was detected in Ae. albopictus. Co-injection of CFAV and ZIKV did not significantly affect ZIKV replication in this species. In contrast, in Ae. aegypti pre-infected with CFAV followed by oral ZIKV challenge, CFAV significantly reduced ZIKV infection rates in the ovaries at day 4 and viral loads in salivary glands at day 10. These findings demonstrate that while CFAV can productively infect Ae. albopictus, it does not undergo vertical transmission in this species, and has no inhibitory effect on ZIKV under the co-infection conditions tested. This study underscores challenges associated with using single ISVs such as CFAV for arbovirus control and highlights the complex, bidirectional role of multiple ISV co-infections. While exploring multi-ISV combinations may offer a potential strategy to enhance antiviral efficacy, their net effect—whether suppression or enhancement of arboviruses—warrants careful investigation.

Aedes aegypti is a major invasive vector in China, where prolonged pyrethroid use has induced resistance, complicating dengue control. This study evaluated the resistance levels of Ae. aegypti to the pyrethroid beta-cypermethrin in Yunnan and explored the underlying mechanisms to inform control strategies. Mosquitoes were collected from five regions of Yunnan in 2015–2016. Larval bioassays, adult diagnostic dose determination, and adult bioassays were conducted to assess resistance to beta-cypermethrin. Mixed-function oxidase (MFO) amount was measured in larvae, and PCR amplification was used to detect mutations in the voltage-gated sodium channel (VGSC) gene. Correlations between enzyme activity, mutations, and phenotypic resistance were analyzed. Larval bioassays indicated that all five populations exhibited resistance to beta-cypermethrin, with resistance ratios ranging from 11.31 to 41.56. The adult diagnostic dose was determined as 0.74668 g/L, with mortality rates ranging from 8.89% to 58.89%, confirming resistance. A significant negative correlation was found between adult mortality and larval LC₅₀ values. MFO amount was closely correlated with resistance levels. The F1534C mutation was the only VGSC mutation detected, and its frequency showed a significant positive correlation with beta-cypermethrin resistance. Our data were collected in 2015–2016; resistance levels may have changed since then, and no confirmatory bioassays were performed by us after 2020. The findings demonstrate that the F1534C mutation and increased MFO amount contribute to enhanced beta-cypermethrin resistance of Ae. aegypti in Yunnan. By linking phenotype resistance to key molecular and biochemical mechanisms, these findings support the continued monitoring of resistance and provide a basis for the evidence-based optimization of dengue vector control strategies.