From Forbes
June 17, 2019
Greece’s Foreign Office is preparing summer tourists for a trip to the country in a slightly different way than usual; by adding mosquitoes to its list of travel perils. More people than ever before are contracting West Nile virus, a disease which is spread by mosquito bites and last year, 50 Greeks died.
West Nile virus is transmitted to humans and animals through the bite of infected culex mosquitoes, which are active from dusk until dawn (other mosquitoes come out during the day). The virus was first identified and classified in 1937 in the West Nile region of Uganda (hence its name) although it hasn’t always been considered very serious because most people who are infected don’t usually exhibit any signs of illness.
For the people who do have symptoms–about 20% of infected people–these will be flu-like, with fever, headaches, diarrhoea and vomiting. However, there are a few–typically 1 in every 150–who will be much more affected and will develop some kind of neuroinvasive disease such as meningitis and encephalitis, leading to possible mental confusion, loss of memory, and convulsions. Unlike other species of mosquitoes, the culex mosquito has a preference for birds so whilst humans are not the preferred meal, the disease can stick around as it is transmitted from bird to bird and it tends to be transported long-distances. It’s overwhelmingly the case that the older you are, the more likely it is that you will be adversely affected by West Nile disease.