West Nile Virus
West Nile Virus (WNV) is a mosquito-borne disease that was first seen in North America in 1999. The most serious manifestation of West Nile Virus infection is fatal encephalitis (inflammation of the brain) in humans and horses, as well as mortality in certain domestic and wild birds. Cases of West Nile Virus in New Mexico have occurred every year since 2003. West Nile Virus infections in humans occur seasonally, with the peak of cases in late summer and early fall.
The risk of acquiring West Nile Virus can be reduced by:
- Using insect repellent
- Reducing the amount of time spent outdoors at dusk and dawn when mosquitoes are most active
- Having screens on your doors and windows to keep mosquitoes out
- Emptying or eliminating water holding containers (where mosquitoes lay their eggs) such as tires, flower pots and buckets
Frequently Asked Questions
This list of frequently asked questions explains about the virus, how people get infected, how it is transmitted, symptoms, treatment, and what to do if you get bitten by a mosquito.
- English: West Nile Virus Frequently Asked Questions
- Spanish: Virus del Nilo Occidental Preguntas Más Frecuentes
Fact Sheet
This fact sheet explains what West Nile Virus is, what the symptoms are, how the infection is spread, how long people are contagious for, what treatments are available, how you can protect yourself and your family, and more.
- English: West Nile Virus Factsheet (English)
- Spanish: El Virus del Nilo Occidental Factsheet (Spanish)
Manual for Investigation
This comprehensive CD Manual - Mosquito-borne Viral Encephalitides provides all the information required to investigate West Nile Virus cases including a summary of the disease, agent details, mode of transmission, period of communicability, incubation period, diagnosis, treatment, surveillance, control measures, and more.
Case Reporting Form
Use this Arbovirus Case Reporting Form to report cases of West Nile virus to NMDOH.
Diagnosis & Laboratory Testing Recommendations
Our West Nile Virus Diagnosis and Laboratory Testing Recommendations for medical providers publication describes the recommendations for diagnostic testing, considerations for when to test for West Nile virus, and more.
Activity in New Mexico
There have been no human cases of West Nile virus in New Mexico in 2024.
There have been 80 Human Cases of West Nile Virus in New Mexico in 2023.
See the following news releases for more information:
- 09/01/2023: New Mexico Department of Health reports first West Nile virus death of 2023
- 08/10/2023: Department of Health reports new cases West Nile virus infections
- 07/28/2023: Department of Health Confirms First Human West Nile Infections of 2023
- 09/12/2022: Department of Health reports first human West Nile virus infection of 2022
- 09/17/2021: West Nile Virus Cases Rise in New Mexico
- 05/21/2020: Department of Health Reports First Human Case of West Nile Virus Infection in New Mexico in 2020
New Mexico Case Data
Case data from previous years are archived below for historical reference.