Other links concerning Notifiable Conditions

• Local Health Jurisdictions

• Report a Notifiable Condition

• Reporting Forms

• Guidelines

• Disease Surveillance Data

• Glossary

• Legal Requirements

• EpiTrends

• Notifiable Conditions & the Health Care Provider (PDF, 645KB)

• Notifiable Conditions & the Hospital  (PDF, 529KB)

• Notifiable Conditions & the Laboratory  (PDF, 314KB)

• Notifiable Conditions & the Local Health Jurisdiction  (PDF, 117KB)

• Notifiable Conditions & the Veterinarian (PDF, 129KB)

• Communicable Disease Epidemiology

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West Nile Virus

Cause: West Nile virus.

Illness and treatment: About 80% of those infected are asymptomatic, around 20% have WNV fever (fever, headache, rash), and less than 1% develop WNV neuroinvasive disease (meningitis or encephalitis, paralysis). Treatment is supportive.

Sources: Many bird species are reservoirs and mosquitoes are the vectors, transmitting the virus through bites to humans and other mammals such as horses.

Prevention: Avoid mosquito bites by wearing appropriate clothing and using insect repellents. Make sure windows and doors are "bug tight."  Maintain window screens. Eliminate breeding sites by draining standing water such as in pots or tires.

Recent Washington trends: Infected birds and horses were first detected in 2002. The first locally acquired human infections were reported in 2006 from Pierce and Clark counties.

2008: Three cases of endemically acquired West Nile virus disease were reported. In addition, one presumptive viremic blood donor was identified.

For current or historical  information on WNV in Washington State, please see the DOH West Nile Virus hompage.

Arboviral (arthropod-borne viral) Diseases, including West Nile virus (WNV) infections, must be reported to local health jurisdictions in Washington State.

Purpose of Reporting and Surveillance

• To identify areas in which West Nile Virus (WNV) is being transmitted.

• To target areas for public education about reducing mosquito habitats and preventing mosquito bites.

• To provide information for mosquito control and environmental health initiatives. 

Reporting Requirements

• Health care providers: notifiable to Local Health Jurisdiction within 3 working days.

• Hospitals: notifiable to Local Health Jurisdiction within 3 working days.

• Laboratories: isolation of WNV or detection of viral antibody or nucleic acid notifiable to Local Health Jurisdiction in which within 2 working days.

• Local Health Jurisdictions: notifiable to DOH Communicable Disease Epidemiology within 7 calendar days of case investigation completion or summary information required within 21 calendar days.

• Veterinarians: Notifiable to Local Health Jurisdiction or Washington State Department of Agriculture.

Last update
November 2009