West Nile encephalitis – does this reemerging disease pose a threat in Croatia?

Sa？etak West Nile encephalitis is a disease transmitted by mosquitoes and is widely distributed in the eastern hemisphere. It is native to Africa, the Middle East, Southwest Asia, Europe and Australia. West Nile virus is known to cause an acute febrile illness with rash, poliarthropathy, lymphadenopathy and encephalitis sometimes accompanied by inflammation of the liver or pancreas. Infection of humans is usually subclinical. Twice as frequent are subclinical versus clinical manifestations, and meningoencephalitis occurs in only 0.7% infected people. The greatest risk factor for severe neurological problems and death is older age (over 70 years) and immunocompromised state. The virus normally circulates between mosquitoes and migratory birds, and is accidentally transferred to humans and horses. Occasionally or seasonally, the disease can occur in an epidemic form outside its natural foci, and the agent then crosses intercontinental barriers by routes of migratory birds and/or vector mosquitoes by aircraft traffic. Epidemics of WNV in humans have been described in Egypt, Israel, South Africa, Europe and Asia. The virus is expanded throughout Europe. As in other zoonoses, populations in close contact with nature are at higher risk to become exposed to vectors of this virus