European countries along the Mediterranean Basin and in other parts of the continent are facing their greatest threat from mosquito-borne diseases in nearly 50 years with the introduction of an invasive, aggressive species from the tropical forests of Southeast Asia.
The Asian tiger mosquito, Aedes albopictus, has spread from its native region and is now found in a number of European countries, including Italy, France, Spain, Slovenia, Croatia, Bosnia and Herzegovina, Montenegro, Greece and Switzerland.
The species is known to transmit a number of arboviruses that threaten human health, including chikungunya and dengue. It is also thought to be a bridge vector for West Nile virus.
“Establishment of Ae. albopictus mosquitoes in the Mediterranean Basin within a few years and the recent emergence of chikungunya epidemics in Italy points to the need for swift public health action,” said Serap Aksoy, a professor at the Yale School of Public Health and co-author of an editorial on the looming health threat posed by the mosquito that appears this week in the journal PLOS Neglected Tropical Diseases. Aksoy is the journal’s co-editor-in-chief.
Ae. Albopictus is know for aggressive biting during daytime hours and it exhibits a number of other traits that make it particularly formidable and have allowed its range to spread dramatically within a few decades. The mosquito can survive cold weather, is able to mature a batch of eggs without blood feeding and the eggs are able to survive other difficult environmental conditions.
Mosquito-transmitted diseases, particularly malaria, plagued much of southern Europe, until the early 1960s when, as a result of years of insect management and eradication efforts, mosquito habitat was successfully reduced.
In addition to Europe, Ae. Albopictus is found on four other continents, including North and South America, Africa and Asia. Its colonization of Europe is believed to have begun in the 1970s in Albania.
Aksoy and colleagues note that, unfortunately, the toolbox to fight such infestations is very small. Given that there are no effective vaccines yet against the main vector-borne diseases, prevention relies heavily on vector control and protection of humans from the bites of infected mosquitoes. In this regard, detailed background information on vector distribution, density and migration dynamics are needed by public health authorities to develop efficient preparedness plans and implement effective emergency actions to be applied at national and international scales.