| ABSTRACT | Climatic changes impact the health of the Mediterranean cities population directly through extreme heat, drought or storms, or indirectly by changes in water availability, food provision and quality, air pollution and other stressors. All have the potential to impact both physical and mental health. The main health effects are related to extreme weather events (including extreme temperatures and floods), changes in the distribution of climate-sensitive diseases and changes in environmental and social conditions. The poorer countries, particularly in North Africa and the Levant, are at highest risk. The current presentation is focused on two main issues – heat related illness and vector-borne diseases: Heat-related illnesses and fatalities can occur when high ambient temperatures (in particular combined with high relative humidity) exceed the body’s natural ability to dissipate heat. In general, elderly people, children, people with pre-existing chronic conditions are most affected. For example, in Israel, high ambient temperature was associated with stroke risk starting from the day before the stroke event, and increasing in strength over a six-day lag. Climate change contributes to the transmission potential of vector-borne diseases since the lifecycle dynamics of the vector species, pathogenic organisms and the reservoir organisms are all sensitive to weather conditions. In the Mediterranean Basin, several vector-borne diseases, sensitive to climatic variations, are common, while others are potential threat. Following the recent climatic and environmental changes, it is expected that VBDs outbreaks will be exacerbated in the region. An example is the West Nile virus (WNV), transmitted by mosquitoes, a vector-borne pathogen of global importance. Its transmission cycle involves both rural ecosystems and urban areas, where the virus circulates between birds and mosquitoes, particularly members of the genus Culex. Under certain environmental conditions it spreads to human settlements where it infects humans and equines, and may cause large epidemics. Ambient temperature plays an important role in viral replication rates and transmission of WNV, affecting the length of incubation, seasonal phenology of mosquito host populations and geographical variation in human case incidence. Elevated ambient temperatures increase growth rates of vector populations, decrease the interval between blood meals, and accelerate the rate of virus evolution Indeed, clear associations have been found during recent years between warm conditions and WNV outbreaks in various locations (mainly cities) in Mediterranean countries including France, Italy, Croatia, Slovenia, Greece, Turkey, Israel and the Mediterranean islands. Dengue, Chikungunya and Zika are also mosquito-borne arboviral diseases of interest to the region. The viruses are transmitted by Aedes aegypti and Ae. albopictus mosquitoes that exhibit widespread distribution throughout tropical, sub-tropical, and temperate zones. As a consequence, the recent establishment and rapid spread of Ae. albopictus in Mediterranean countries is a cause of major concern, in parallel with the potential risks of diseases transmission by Ae. Aegypti which currently exists in part of the region (e.g. Turkey, Israel or Egypt). Most cities in the Mediterranean Basin are compact and densely populated. Air conditioning is used in regions with advanced socio-economic level. Many activities, particularly social gatherings, occur in outdoor locations such as shaded balconies, courtyards, outdoor restaurants and in the countryside - all ideal for contact with the vector. In view of the climatic projections and the vulnerability of Mediterranean cities, climate change mitigation and adaptation become ever more imperative. In order to minimize climate-aggravated health impacts, health systems in the Mediterranean should: Implementing measures for adequate preparedness of emergency medicine institutions and professionals; Monitoring climate-related morbidity and mortality and designing interventions; Monitoring and surveillance of vector-borne diseases (and other climate sensitive diseases), including across borders with neighboring countries; Implementation of heat-health warning system and more generally heat-health action plans; Increase public awareness to climate change-related health risks, and recommended prevention of negative health outcomes, including behavior during heat waves, elimination of habitats for vectors, etc. Without an effective interventions and cooperation between the Mediterranean countries, parallel with mitigation actions to reduce greenhouse gas emission, climate change will lead to an increasing level of morbidity and mortality in the region, with a higher risk for the most vulnerable populations. |