West Nile virus in Romania 2026: what households in the affected counties need to know

Romania is a historically recurring West Nile virus country in central-eastern Europe. The country was the site of the 1996 Bucharest-centred outbreak, the first major West Nile virus outbreak recorded in Europe, when Romania identified about 400 cases (ECDC). Romania has reported WNV cases on the EU/EEA platform since at least the 2010s. In the most recent completed season, 2025, Romania reported 49 locally acquired cases (ECDC).

The 2026 Romanian WNV season was under way at the time of writing. ECDC publishes the current weekly counts on its seasonal surveillance page (ECDC), and the most recent completed season it summarises is 2025. In 2025, 14 countries in Europe reported 1 112 locally acquired cases, with the earliest and latest dates of onset on 19 May and 27 October 2025 respectively (ECDC).

This landing is written for Romanian households in the affected counties and for travellers, seasonal workers, agricultural contractors, and second-home owners returning to rural and Danube-floodplain properties in July and August. It covers the 2026 surveillance signal, the historical Romanian geography of WNV transmission, the clinical picture, the household protection layer, and the Romanian reporting infrastructure that a household should know about.

The 2026 Romanian season so far

The 2026 Romanian WNV season was under way at the time of writing. ECDC's seasonal surveillance page carries the current weekly counts (ECDC).

The most recent completed season that ECDC summarises is 2025: as of 3 December 2025, 14 countries in Europe reported 1 112 locally acquired cases, including 49 in Romania (ECDC). ECDC reports that most WNV infections in humans and equids are observed between July and September, when mosquitoes are active (ECDC). The Romanian season typically opens in late June to early July and runs through the summer into the autumn.

The historical Romanian geography of WNV transmission

Romania has reported WNV cases on the EU/EEA platform since at least the 2010s. The 1996 Bucharest-centred outbreak was the first major WNV outbreak recorded in Europe, when Romania identified about 400 cases (ECDC). The 1996 outbreak is the structural reference point for Romanian WNV surveillance and is one reason that Romania runs an integrated human and veterinary surveillance system.

The recurrently affected Romanian counties are in the south and southeast, the Danube floodplain and the Black Sea coast: Dolj, Olt, Teleorman, Giurgiu, Ilfov, Ialomița, Călărași, Brăila, Galați, Tulcea, and Constanța. Bucharest and its metropolitan area have been recurrently affected in high-circulation years, and the Ilfov county belt around Bucharest is the focus of the central-Romanian WNV activity. The Danube floodplain counties carry the bulk of the historical case load, with Brăila, Ialomița, and Galați as the most consistent focus.

The Romanian national reference for WNV surveillance is the National Institute of Public Health (INSP), which runs the integrated human surveillance, and the National Centre for Communicable Diseases Surveillance and Control (CNSCBT), which coordinates the regional public-health authorities. The veterinary surveillance is run by the National Sanitary Veterinary and Food Safety Authority (ANSVSA) in partnership with the veterinary faculties, and the equine WNV surveillance is the reason that horse cases in the Danube floodplain counties are flagged as an early sentinel for human risk.

The Culex ecology of Romanian conditions

The Culex pipiens ecology in Romanian conditions is shaped by the Danube floodplain. The floodplain is a low-lying, marshy, intensively farmed terrain with high Culex pipiens breeding-site density in standing water from river overflow, irrigation channels, fish ponds, drainage accumulations, and any container that holds water. The combination of high mosquito density, a large resident and migratory bird population, and a network of rural and peri-urban settlements is the structural driver of the consistent Danube-floodplain WNV case load.

For a Romanian household in the Danube-floodplain counties, the source-reduction checklist is the Culex-specific one: blocked roof gutters, water butts, ornamental water features, used tyres stored flat, flooded cellars, irrigation channels, fish ponds, and any standing water that has been undisturbed for a week or more. The Culex development cycle depends on temperature and is fastest in warm summer water, so a weekly walk around the house and garden is enough to break the local cycle (ECDC).

Culex pipiens is a pest in urban environments, where females bite at night and rest indoors (ECDC). The bedroom is the highest-exposure room in a Romanian urban home, and the bedroom is the right place to start the household protection layer.

The clinical picture for a Romanian household

For a Romanian household in the affected counties, the clinical reading is the same as for any other household in the region. About 80 per cent of WNV infections are asymptomatic. About 20 per cent cause a self-limiting febrile illness, West Nile fever, with fever, headache, muscle aches, fatigue, and sometimes a rash (ECDC). The incubation period is usually two to six days, and up to 21 days in people with weakened immune systems (ECDC).

Fewer than 1 per cent of infections progress to neuroinvasive disease, presenting as meningitis, encephalitis, or acute flaccid paralysis. The case fatality ratio among patients with neuroinvasive disease can be up to 17 per cent (ECDC). A 2026 review of West Nile neuroinvasive disease management reports the same figure and notes that clinical care remains supportive (PubMed). There is no specific antiviral and no human vaccine, so hospital care is supportive (WHO). Older adults and people who are immunocompromised are at higher risk of severe disease (ECDC).

The clinical decision point is early recognition, particularly in older or immunocompromised household members developing high fever, neck stiffness, confusion, weakness, or seizures during the transmission season, when most infections occur between July and September (ECDC), and prompt presentation to emergency services. The 1996 outbreak is the structural reminder that the neuroinvasive form can progress quickly, and that early presentation to hospital is the right response.

The household protection layer for a Romanian home

The household protection layer for a Romanian household in the affected-county footprint is the four-part layer set out here, applied to the Romanian Culex and Danube-floodplain ecology.

1. A net over the bed. For sleeping adults and children, an untreated mosquito net draped over the bed is the single most reliable chemical-free barrier to Culex bites. A framed canopy is preferable in a child's room. The net is the load-bearing protection during the sleeping hours.
2. Screens on bedroom windows and doors. Tight-fitting insect screens on the bedroom windows, and on any door left open for cross-ventilation in summer, prevent Culex from entering the room in the first place. Leave the screens in place through the off-season, because Culex larvae can be found from mid-spring (ECDC).
3. Source reduction around the house. A weekly walk to drain, dry, or cover any standing water that has been undisturbed. The Culex development cycle depends on temperature and is fastest in warm summer water, so a weekly cadence is enough to break the cycle (ECDC). In the Danube-floodplain counties, irrigation channels, fish ponds, and any container that holds rainwater are the priority breeding sites.
4. Repellent during outdoor evening hours. Where presence on the terrace, in the garden, at a fishery, or at an outdoor event during the evening and night window is unavoidable, an age-appropriate skin repellent, applied to the label, is the third line of defence.

The chemical layer (residual indoor spraying, outdoor ultra-low-volume adulticiding, larviciding of standing water) is a public-health tool used by municipal and county vector control in coordination with INSP and CNSCBT. It complements, but does not replace, the household physical-barrier layer.

The equine sentinel and what it tells the household

WNV also infects horses. Most equine infections are asymptomatic, and about 10 per cent show neurological signs, so a confirmed equine case is a signal that the virus is circulating locally (ECDC).

The ANSVSA veterinary surveillance bulletins carry the per-county equine case counts, and INSP and CNSCBT integrate the equine signal into the human surveillance picture. For a Romanian household in a county with confirmed equine WNV cases, the household protection layer is not optional: it is the load-bearing response for a local transmission cycle.

The product-class claims for Romanian consumers

The Romanian consumer-protection reading is the same product-class separation as elsewhere in the region.

Untreated nets, framed canopies, gazebo nets, and baby or crib canopies are general textile products. They make no chemical claims, they carry no biocidal-product registration, and they are the right product class for the household physical-barrier layer. The claims that apply are "physical barrier", "chemical-free", "suitable for all ages including babies and pregnant women", and "reusable, washable". They are not "WHO-prequalified" and not "EU BPR authorised".

Treated nets carry a permethrin treatment and fall under the EU Biocidal Products Regulation (Regulation (EU) No 528/2012) (EUR-Lex). In the global public-health context, insecticide-treated nets are a core malaria-control intervention (WHO), and WHO runs a prequalification scheme that assesses essential health products for procurement in countries without a well-established national regulator (WHO). The biocidal rules that apply to treated nets do not apply to untreated household products.

Plug-in vaporisers, mosquito coils, citronella candles, and aerosol sprays are a different product class, and the load-bearing protection remains the net and the screen. The supplement is a repellent on exposed skin during the evening and night hours when Culex is active (ECDC). Plug-in vaporisers vary widely in formulation.

Frequently asked questions for Romanian households

Question: Where in Romania is West Nile virus circulating in 2026? ECDC publishes the current counts on its seasonal surveillance page (ECDC). The most recent completed season, 2025, recorded 49 locally acquired cases in Romania (ECDC). The recurrently affected counties are in the south and southeast (the Danube floodplain and the Black Sea coast): Dolj, Olt, Teleorman, Giurgiu, Ilfov, Ialomița, Călărași, Brăila, Galați, Tulcea, and Constanța. Bucharest and its metropolitan area have been recurrently affected in high-circulation years. The INSP and CNSCBT bulletins carry the per-county detail.

Question: When is the Romanian WNV season? WNV infections in humans and equids are observed between July and September, when Culex mosquitoes are active (ECDC). The 1996 Bucharest-centred outbreak was the first major outbreak recorded in Europe, when Romania identified about 400 cases (ECDC).

Question: Is there a vaccine? No. There is no human vaccine against WNV, and there is no specific antiviral. Hospital care is supportive (WHO).

Question: Is a mosquito net enough to protect my family? An untreated net over the bed, plus tight-fitting window and door screens, plus source reduction around the home, plus age-appropriate repellent use during outdoor evening hours, is the complete household protection layer. The combination is what works.

Question: What is the official source for the case count? ECDC publishes the EU/EEA weekly counts and the seasonal summaries (ECDC). In Romania, the National Institute of Public Health (INSP) and the National Centre for Communicable Diseases Surveillance and Control (CNSCBT) publish the national and per-county bulletins.

Question: Should I be more careful if a horse in my county has died of WNV this year? Yes. A confirmed equine WNV case in your county is a signal that local transmission is under way, and is a reason to tighten the household protection layer for the duration of the season. The net, the screen, the source reduction, and the repellent are all more important, not less, in a county with documented equine infection.

How to use this landing

This page is the Romanian country landing in the Mosticare 2026 WNV coverage. It is paired with the European hub (the evergreen entry point) and the protection guide (the practical household-layer detail). The structural facts do not change; the case counts do. For the live numbers, the right place to look is the ECDC seasonal surveillance page (ECDC) and the INSP and CNSCBT bulletins for the per-county detail. The household protection layer is the layer every Romanian household in the affected region has under its own control, and it is the layer that operates at the human-vector interface, independent of the case count of any single week.

Sources

1. European Centre for Disease Prevention and Control. Factsheet, West Nile fever. Clinical features, case fatality up to 17 per cent, the 1996 Romania outbreak of about 400 cases, equine infection, and the absence of a specific vaccine or treatment. https://www.ecdc.europa.eu/en/west-nile-fever/facts/factsheet-about-west-nile-fever
2. European Centre for Disease Prevention and Control. West Nile virus historical data. 2025: 1 112 cases across 14 countries, including 49 in Romania. https://www.ecdc.europa.eu/en/west-nile-fever/surveillance-and-disease-data/historical
3. European Centre for Disease Prevention and Control. Weekly updates: seasonal surveillance in humans for West Nile virus. Current weekly counts. https://www.ecdc.europa.eu/en/publications-data/seasonal-surveillance-west-nile-virus-infections-weekly-report
4. European Centre for Disease Prevention and Control. Factsheet, Culex pipiens. Night biting, indoor resting, the temperature-dependent development cycle. https://www.ecdc.europa.eu/en/infectious-disease-topics/related-public-health-topics/disease-vectors/facts/mosquito-factsheets/culex-pipiens
5. World Health Organization. West Nile virus fact sheet. Approximately 80 per cent of infected people show no symptoms; no vaccine is available for humans. https://www.who.int/news-room/fact-sheets/detail/west-nile-virus
6. World Health Organization. Malaria fact sheet. Insecticide-treated nets are a core malaria-control intervention. https://www.who.int/news-room/fact-sheets/detail/malaria
7. World Health Organization. Regulation and Prequalification. WHO prequalifies essential health products. https://www.who.int/teams/regulation-prequalification
8. European Union. Regulation (EU) No 528/2012 on biocidal products. EUR-Lex permanent record. https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32012R0528
9. Curtolo A, et al. West Nile Neuroinvasive Disease: Current Management, Emerging Therapies and Future Clinical Trial Priorities. Reviews in Medical Virology, 2026;36(4):e70182. https://pubmed.ncbi.nlm.nih.gov/42431607/
10. European Centre for Disease Prevention and Control. West Nile virus weekly case-data dashboard. https://wnv-weekly.ecdc.europa.eu/

Last updated: 21 July 2026.