The geographic range of vector-borne diseases, especially mosquito-borne diseases such as malaria and the dengue, has expanded rapidly over the last 80 years. Now more than half of the world population is at risk as, spurred by global warming and urbanization, outbreaks of mosquito-borne diseases will spread in the coming decades across parts of northern Europe, Asia, North America and Australia that are currently unaffected.
ICREA Professor Rachel Lowe, who leads the global health resilience group at the Barcelona Supercomputing Center in Spain, will discuss the changing global threat of vector-borne diseases. He will also discuss the critical importance of improving surveillance and early warning systems to address this now almost global phenomenon, in a new research review to be presented at this year’s Escmid (formerly Eccmid) Global Congress in Barcelona.
“Global warming due to climate change means that disease vectors that transmit and spread malaria and dengue may find a home in more regionswith outbreaks occurring in areas where people are likely to be immunologically naïve and public health systems unprepared,” it warns. “The stark reality is that longer warm seasons will widen the seasonal window for the spread of transmitted diseases by mosquitoes and will favor outbreaks that are increasingly more frequent and increasingly complex to address.
Previously, the dengue (transmitted by mosquitoes that bite during the day) was largely limited to tropical and subtropical regions because frigid temperatures kill mosquito larvae and eggs, but longer warm seasons have allowed dengue to become the disease. mosquito-borne virus that spreads most rapidly in the world.
Nine of the 10 most favorable years for dengue transmission have occurred since 2000, allowing dengue-carrying mosquitoes to invade 13 European countries, and 2023 will see local spread of the disease in France, Italy and Spain. The number of dengue cases reported to WHO has multiplied by eight in the last two decadesfrom 500,000 in 2000 to more than five million in 2019.
Professor Lowe will explain how her recent research into climate extremes in the Caribbean found that drought conditions followed four or five months later by warmer temperatures than usual and excessive rains increase the chances of dengue outbreaks.
“Droughts and floods Related to climate change can lead to increased transmission of the virus, and stored water provides additional breeding grounds for mosquitoes. Lessons from previous outbreaks underscore the importance of assessing future risks of vector-borne diseases and preparing contingencies for future outbreaks,” she notes.
Projections suggest that if global warming can be limited to the ambitious 1°C target, the population at risk of malaria and dengue is expected to increase by 2.4 billion peoples by 2100, compared to the period 1970-1999. However, if the current trajectory of high carbon emissions and population growth continues, twice as many additional people (4.7 billion) will be affected by dengue and malaria by the end of the century.
“With climate change looking so difficult to address, we can expect to see more cases and possibly deaths from diseases such as dengue and malaria across continental Europe. We must anticipate outbreaks and act to intervene early to prevent diseases from occurring in the first place. “Efforts should focus on improving surveillance with early warning and response systems similar to those seen in other parts of the world, to more effectively target finite resources to the highest risk areas to control and prevent disease outbreaks and save lives.” , warns the teacher.
By combining surveillance of disease-carrying insects with climate forecasts, researchers are developing ways to predict when and where epidemics might occur and target interventions to the highest risk areas in advance. One such project, led by Lowe, uses a powerful supercomputer to understand how climate and disease transmission are linked to predict outbreaks of mosquito-borne diseases in 12 countries.
“By analyzing weather patterns, finding mosquito breeding sites with drones, and gathering information from local communities and health officials, we hope to give communities time to prepare and protect yourself“explains Professor Lowe.
