West Nile Virus Confirmed in Wine Country

France's Agence régionale de santé Nouvelle-Aquitaine (ARS) recenlty confirmed a patient had been infected with West Nile virus (WNV) in New Aquitaine.

This WNV patient is from Bordeaux, and ARS is investigating four suspected cases.

Previously, human infections with WNV were reported in France's Mediterranean (PACA and Occitanie regions).

"Their state of health does not inspire concern, and they are on the way to recovery," said the ARS statement on August 1, 2023.

The virus was also detected in horses in the Nouvelle Aquitaine region last autumn. 

The virus was first identified in Uganda in 1937, west of the White Nile River.

WNV was first identified in France in the 1960s but has spread in France and southern Europe.

In Europe, a total of five human cases of WNV infection (Greece (3), Hungary (1), and Italy (1)) were reported from EU/EEA countries as of July 26, 2023.

Since 1999, WNV has become the leading cause of arthropod-borne viral disease in the United States, says the U.S. Centers for Disease Control and Prevention (CDC).

A study published on June 22, 2023, found that about 35% of patients hospitalized for WNV disease in six independent cohorts from the EU and U.S. carry auto-Abs neutralizing IFN-α and/or -ω.

The prevalence of these antibodies was highest in patients with encephalitis (∼40%), 

As of August 1, 2023, 17 U.S. States have reported 90 human WNV cases and 68 Neuroinvasive Human Disease (meningitis or encephalitis) patients this year.

In 2022, a total of 1,126 cases of WNV disease in people were reported in Arizona, Colorado, and California. In Maricopa County, (Phoneix) Arizona, 1,487 WNV cases were reported in 2021, and 7% were related deaths.

As of August 4, 2023, there are no U.S. FDA-approved WNV vaccines. However, active human clinical studies are ongoing.