The West Nile virus is entering a phase of escalation across Greece, with health experts warning that the situation is expected to worsen in the coming weeks as confirmed cases continue to rise. Laboratory-confirmed samples from patients are increasing steadily—particularly in Eastern Attica, where authorities have intensified mosquito control efforts, including ongoing aerial and ground spraying campaigns.
Surge in Confirmed Cases
According to Professor Athanasios Tsakris, Head of Microbiology at the National and Kapodistrian University of Athens’ Medical School, the volume of clinical samples submitted for testing—and the proportion returning positive—is notably high. ‘The number of samples arriving is substantial, and the number of positive results is significant, indicating rapid spread over recent weeks, especially in Eastern Attica,’ he said.
Samples are sent from hospitals to specialized reference laboratories, where diagnosis relies on both serological testing (for antibodies in cerebrospinal fluid or blood) and molecular assays detecting the virus’s genetic material. Results are typically available within 24 hours, enabling timely clinical decisions in suspected cases.
Underreporting Is Widespread
Professor Gkikas Magiorkinis, an infectious disease expert, emphasized that official figures—currently standing at 157 confirmed cases—represent only a fraction of actual infections. ‘Think at least tenfold, possibly even one hundred times higher,’ he stated. ‘Most people experience such mild symptoms—or none at all—that they never seek medical attention, and the virus passes unnoticed. In other words, they “brush it off” and recover without ever realizing they were infected.’
Incubation and Symptoms
The incubation period after a bite from an infected mosquito ranges from two to six days. Initial symptoms often include fever, headache, and muscle pain. In more severe cases—typically affecting less than 1% of infected individuals—neuroinvasive disease may develop later, involving the central nervous system (e.g., meningitis or encephalitis).
Research published in JAMA Internal Medicine, based on a 12-year U.S. surveillance study, indicates men appear more susceptible to severe illness than women. Additional risk factors include underlying conditions such as multiple sclerosis, chronic alcohol use, immunosuppressive therapy, hematologic malignancies, stroke history, chronic kidney disease, and hypertension.
Health authorities anticipate the outbreak will persist through the remainder of summer, urging continued vigilance, especially in endemic areas like Eastern Attica, and recommending protective measures—including insect repellent, long-sleeved clothing, and eliminating stagnant water sources near homes.