West Nile Virus 2026: Early Season Detected in Texas, Louisiana & California | Virus Watcher
10 Épidémie ActivesWest Nile Virus is showing early 2026 season activity across multiple states before the typical transmission season begins. Positive mosquito pools have been confirmed in Texas (San Antonio, Frisco), Louisiana (New Orleans), and six California counties. Human cases have already been confirmed in Colorado. Peak transmission season runs July through September — and an above-average season is projected for 2026. Most infections are mild or asymptomatic, but about 1 in 150 infected people develop severe, potentially fatal brain inflammation.
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Qu'est-ce que West Nile Virus?
West Nile Virus arrived in the U.S. in 1999 and has since become the leading mosquito-borne disease in the country. It's transmitted by Culex mosquitoes that bite infected birds. While 80% of infected people have no symptoms, severe cases can cause encephalitis or meningitis with long-term neurological effects. Age over 60 significantly increases risk of severe disease.
SymptĂ´mes
- Mild (West Nile fever): Fever, headache, body aches, joint pain, vomiting, diarrhea, rash
- Severe: High fever, severe headache, stiff neck, disorientation, tremors, seizures
- Neurological: Muscle weakness, vision loss, paralysis, coma
- Long-term effects: Fatigue, memory problems, muscle weakness (can persist months/years)
Transmission
Transmitted through bites of infected Culex mosquitoes. Rarely through blood transfusion, organ transplant, mother to fetus, or breastfeeding. NOT spread person-to-person through casual contact.
Période de Contagiosité : Not contagious person-to-person; can be in blood of infected person during illness
Prévention
- Use EPA-registered insect repellents (DEET, picaridin, IR3535, oil of lemon eucalyptus)
- Wear long sleeves and pants at dawn/dusk when mosquitoes most active
- Install/repair window and door screens
- Use air conditioning when possible
- Eliminate standing water (buckets, flower pots, bird baths, gutters)
- Change water in pet bowls, birdbaths weekly
- Treat or drain swimming pools, fountains
- Community mosquito control programs (spraying, larvicides)
- Avoid outdoor activities at dawn/dusk during peak season
Live West Nile Virus Global Case Map
5 countries with reported activity. Updated from real-time surveillance data.
United States — State Detail
1 state with reported activity. Click a state for detailed surveillance.
Épidémies Actives et Cas Récents
Renseignements en temps réel issus de la surveillance sanitaire mondiale et de la surveillance par IA
Sources de données : BEACON, ProMED, OMS, CDC et plus de 50 agences nationales de santé
✓ Données en direct mises à jour en temps réel depuis les sources de santé mondiales
West Nile virus spreads in Europe? Greece reports surge, Italy leads
Greece and Italy are reporting the highest West Nile virus activity in Europe this season.
The spread of West Nile virus -- a mosquito-borne disease transmitted primarily by infected mosquitoes -- in Greece is showing an upward trend, according to the National Public Health Organisation.
During the past week, 23 new cases of West Nile virus infection have been reported. In total, from the start of the transmission season in spring up to 5 August, 65 cases have been recorded, 54 of which present
đź“° 12 news sources reporting on this story.
Virus warning in Spain issued after one person dies
Holidaymakers heading to Spain have been warned to take precautions after the country's first death this year from a virus - with experts fearing the disease could spread to more hotspots.
An 82-year-old man from Dos Hermanas, near Seville, has become Spain's first confirmed fatality from West Nile virus this year after being admitted to hospital with meningoencephalitis caused by the mosquito-borne infection. Spanish health authorities have confirmed at least 19 human cases this season, the vas
đź“° 48 news sources reporting on this story.
Cases of West Nile virus are climbing -- these products can help keep you protected
West Nile virus is most commonly spread through mosquitoes and symptoms can range from non-existent to severe.Getty
Summer isn't over yet -- and neither is mosquito season, which means you still have a very real chance of catching West Nile virus. In fact, every year, cases of this virus typically peak in late August to early September, according to the Centers for Disease Control and Prevention (CDC). And the rise in cases has already started -- in recent weeks, cases have been reported in 24 s
đź“° 37 news sources reporting on this story.
More than 240 cases of West Nile fever in Europe
More than 240 cases of West Nile virus infection have been reported in Europe since the start of the season. Italy has been particularly hard hit. The WHO has called for increased vigilance.
As of last Wednesday, a total of 241 cases had been reported in seven European countries in which people had been infected locally -- that is, they had not contracted the virus while traveling.
According to the European Center for Disease Prevention and Control (ECDC), 139 cases were reported from Italy, 61
đź“° 52 news sources reporting on this story.
đź”— Read more at News.de
New virus warning for Brits travelling to Europe 'no vaccine'
The World Health Organisation has issued a warning over a fast-growing outbreak
Brits heading to some of Europe's most popular sunshine hotspots this summer are being urged to take extra care, after health chiefs warned a fast-growing West Nile virus outbreak is spreading across the continent. The World Health Organisation (WHO) says recurring heatwaves are creating ideal conditions for infected mosquitoes to thrive, helping the virus reach new areas just as millions travel during the busiest ho
đź“° 23 news sources reporting on this story.
Deadly virus found in holiday hotspots loved by Brits as 'red alert' issued
Mosquitoes carrying deadly West Nile virus have been detected in the Spanish regions of Fuengirola and Mijas - both of which are visited by thousands of Brits each year
Two popular Spanish holiday hotspots are on red alert after several people were struck down by the potentially deadly West Nile virus.
Mosquitoes which carry the disease have been detected in Fuengirola and Mijas, both visited by thousands of Brits every year. Health chiefs say the insects were found in traps installed in both m
đź“° 63 news sources reporting on this story.
West Nile Virus turns deadly in California as officials issue update
California has recorded its first West Nile virus death of 2026 after a Kings County resident died from the mosquito-borne illness, health officials announced Monday.
The death comes weeks after Kings County confirmed its first human case of the 2026 season, according to KGPW.
The infection was detected almost two weeks later than the county's first case in 2025.
"We are saddened to report that a Kings County resident has passed away due to West Nile Virus," Rose Mary Rahn, director of the Kin
đź“° 19 news sources reporting on this story.
đź”— Read more at WTOP
Mosquito pool in Buda tests positive for West Nile Virus
AUSTIN (KXAN) -- A mosquito trap in Buda has tested positive for West Nile virus, according to the Hays County Development Services Mosquito Surveillance Program.
The positive sample was collected in the 78610 ZIP code and marks the fifth West Nile virus-positive mosquito pool identified in Hays County this year. County officials said no human cases of West Nile virus have been reported in Hays County so far.
Statewide, the Texas Department of State Health Services has reported 905 positive mos
đź“° 17 news sources reporting on this story.
West Nile virus found in two mosquito traps in DeKalb County, health officials say
Dan Raby, the senior digital producer for CBS News Atlanta, has been covering everything happening around Georgia for more than a decade.
Mosquitoes found in two traps in DeKalb County have tested positive for the West Nile virus, officials say.
Officials with DeKalb Public Health say the positive traps were found in two different ZIP codes: 30088 in unincorporated DeKalb and Redan, and 30360 in Doraville.
There have been no reported human cases of infection in the county in 2026, the agency r
đź“° 84 news sources reporting on this story.
How Chicago Health Department is protecting against West Nile virus
The Chicago Department of Public Health is taking steps to prevent West Nile virus in the area.
Health officials said they are spraying a chemical used to control mosquitoes in outdoor residential and recreational areas, specifically in the Pullman and South Deering neighborhoods and near O'Hare Airport.
Spraying will take place from dusk on Wednesday and Thursday until around 1 a.m.
This is just one of the ways CDPH aims to control West Nile virus in the city.
The Health Department also lays
đź“° 24 news sources reporting on this story.
Don't find out from the news. Track this outbreak and 200+ diseases in real time.
Ressources Expertes et Références
Informations fiables provenant des principales organisations de santé
CDC
Directives officielles des Centers for Disease Control and Prevention des États-Unis
Voir les Ressources du CDC →WHO
Surveillance mondiale des maladies et directives de l'Organisation Mondiale de la Santé
Voir les Ressources de l'OMS →Contenu Révisé Médicalement
Les informations sur les maladies sur Virus Watcher sont révisées par notre Épidémiologiste en Chef, ancien analyste principal du CDC pour les prévisions FluSight. Les données épidémiques sont agrégées à partir de sources vérifiées notamment BEACON, ProMED, OMS, CDC et plus de 50 agences nationales de santé. Ces informations sont à des fins éducatives et ne doivent pas remplacer les conseils médicaux professionnels.
Dernière révision : 2026-08-13
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