Sandfly fever viruses in Italy

Area of Science:

• Virology
• Medical Entomology
• Infectious Diseases

Background:

• Sandfly fever Sicilian and Naples viruses were initially identified in Italy.
• Toscana virus, antigenically related to Naples virus, was isolated from Italian sandflies in 1971.
• Toscana virus is a significant human pathogen associated with acute neurologic conditions.

Purpose of the Study:

• To investigate the prevalence and trends of sandfly fever viral infections in the Mediterranean.
• To assess the current role of Toscana virus in human neurologic diseases.
• To determine the potential geographic distribution of Toscana virus.

Main Methods:

• Serological surveys to detect antibodies against sandfly fever Sicilian, Naples, and Toscana viruses.
• Analysis of historical data on viral isolation and disease incidence.
• Review of clinical case reports of aseptic meningitis and meningoencephalitis.

Main Results:

• Sandfly fever Sicilian and Naples viral infections have declined significantly in Mediterranean areas post-1940s malaria eradication campaigns.
• Toscana virus causes annual cases of aseptic meningitis and meningoencephalitis in Central Italy, particularly during summer months.
• Toscana virus is likely present in other Mediterranean regions harboring Phlebotomus sandflies.

Conclusions:

• Toscana virus has emerged as a significant cause of viral meningitis and encephalitis in Central Italy.
• The decline of older sandfly fever viruses correlates with successful malaria control programs.
• Ongoing surveillance for Toscana virus is warranted in Mediterranean countries with suitable sandfly vectors.