Risk factors of exposure to Aedes albopictus bites in mainland France using an immunological biomarker

Orthopoxvirus Seroprevalence and Infection Susceptibility in France, Bolivia, Laos, and Mali

To determine a demographic overview of orthopoxvirus seroprevalence, we tested blood samples collected during 2003-2019 from France (n = 4,876), Bolivia (n = 601), Laos (n = 657), and Mali (n = 255) for neutralizing antibodies against vaccinia virus. In addition, we tested 4,448 of the 4,876 samples from France for neutralizing antibodies against cowpox virus. We confirmed extensive cross-immunity between the 2 viruses. Seroprevalence of antibodies was <1% in Bolivia, <5% in Laos, and 17.25% in Mali. In France, we found low prevalence of neutralizing antibodies in persons who were unvaccinated and vaccinated for smallpox, suggesting immunosenescence occurred in vaccinated persons, and smallpox vaccination compliance declined before the end of compulsory vaccination. Our results suggest that populations in Europe, Africa, Asia, and South America are susceptible to orthopoxvirus infections, which might have precipitated the emergence of orthopoxvirus infections such as the 2022 spread of monkeypox in Europe.

Climate change and infectious disease in Europe: Impact, projection and adaptation

Europeans are not only exposed to direct effects from climate change, but also vulnerable to indirect effects from infectious disease, many of which are climate sensitive, which is of concern because of their epidemic potential. Climatic conditions have facilitated vector-borne disease outbreaks like chikungunya, dengue, and West Nile fever and have contributed to a geographic range expansion of tick vectors that transmit Lyme disease and tick-borne encephalitis. Extreme precipitation events have caused waterborne outbreaks and longer summer seasons have contributed to increases in foodborne diseases. Under the Green Deal, The European Union aims to support climate change health policy, in order to be better prepared for the next health security threat, particularly in the aftermath of the traumatic COVID-19 experience. To bolster this policy process we discuss climate change-related hazards, exposures and vulnerabilities to infectious disease and describe observed impacts, projected risks, with policy entry points for adaptation to reduce these risks or avoid them altogether.

Aedes albopictus D7 Salivary Protein Prevents Host Hemostasis and Inflammation

Mosquitoes inject saliva into the host skin to facilitate blood meal acquisition through active compounds that prevent hemostasis. D7 proteins are among the most abundant components of the mosquito saliva and act as scavengers of biogenic amines and eicosanoids. Several members of the D7 family have been characterized at the biochemical level; however, none have been studied thus far in Aedes albopictus, a permissive vector for several arboviruses that causes extensive human morbidity and mortality. Here, we report the binding capabilities of a D7 long form protein from Ae. albopictus (AlboD7L1) by isothermal titration calorimetry and compared its model structure with previously solved D7 structures. The physiological function of AlboD7L1 was demonstrated by ex vivo platelet aggregation and in vivo leukocyte recruitment experiments. AlboD7L1 binds host hemostasis agonists, including biogenic amines, leukotrienes, and the thromboxane A2 analog U-46619. AlboD7L1 protein model predicts binding of biolipids through its N-terminal domain, while the C-terminal domain binds biogenic amines. We demonstrated the biological function of AlboD7L1 as an inhibitor of both platelet aggregation and cell recruitment of neutrophils and eosinophils. Altogether, this study reinforces the physiological relevance of the D7 salivary proteins as anti-hemostatic and anti-inflammatory molecules that help blood feeding in mosquitoes.

Narrative Review on Health-EDRM Primary Prevention Measures for Vector-Borne Diseases

Climate change is expanding the global at-risk population for vector-borne diseases (VBDs). The World Health Organization (WHO) health emergency and disaster risk management (health-EDRM) framework emphasises the importance of primary prevention of biological hazards and its value in protecting against VBDs. The framework encourages stakeholder coordination and information sharing, though there is still a need to reinforce prevention and recovery within disaster management. This keyword-search based narrative literature review searched databases PubMed, Google Scholar, Embase and Medline between January 2000 and May 2020, and identified 134 publications. In total, 10 health-EDRM primary prevention measures are summarised at three levels (personal, environmental and household). Enabling factor, limiting factors, co-benefits and strength of evidence were identified. Current studies on primary prevention measures for VBDs focus on health risk-reduction, with minimal evaluation of actual disease reduction. Although prevention against mosquito-borne diseases, notably malaria, has been well-studied, research on other vectors and VBDs remains limited. Other gaps included the limited evidence pertaining to prevention in resource-poor settings and the efficacy of alternatives, discrepancies amongst agencies' recommendations, and limited studies on the impact of technological advancements and habitat change on VBD prevalence. Health-EDRM primary prevention measures for VBDs require high-priority research to facilitate multifaceted, multi-sectoral, coordinated responses that will enable effective risk mitigation.