Legal reporting requirements

Health care providers and hospitals should report suspected or confirmed WNV cases to Public Health - Seattle & King County within 3 work days. Laboratories that isolate WNV or detect virus specific antibody or viral nucleic acid should report to Public Health-Seattle & King County within 2 work days. For information on how to report a suspected or confirmed case, go to: www.metrokc.gov/health/providers or call 206-296-4774.

Please report cases with any of the following:

• Suspected or confirmed WNV neuroinvasive disease:
  Fever (in the absence of a more likely diagnosis) in a patient with at least one of the following:
  • Acute change in mental status (e.g., disorientation, obtundation, stupor, or coma), or
  • Other acute central or peripheral neurological dysfunction (e.g., paresis or paralysis, nerve palsies, sensory deficits, abnormal reflexes, seizures, or movement disorders), or
  • Cerebrospinal fluid (CSF) pleocytosis associated with an illness compatible with meningitis, or
  • WNV-specific IgM antibodies measured by any serologic testing method or detection of viral nucleic acid in CSF
    
    
• WNV non-neuroinvasive disease:
  Fever (in the absence of a more likely diagnosis) in a patient who has laboratory evidence of WNV disease:
  • WNV-specific IgM antibodies in serum measured by any serologic testing method, or
  • Isolation of WNV from, or detection of viral nucleic acid in blood
    
    
• Acute flaccid paralysis or presumed Guillain-Barré syndrome even in the absence of fever and other neurologic symptoms.
  
  
• Suspected WNV disease or asymptomatic WNV infection with laboratory evidence of WNV in the following patients, even in the absence of fever and other neurologic symptoms:
  • A pregnant woman
  • A neonate or breastfeeding infant of a WNV infected mother
  • Someone who donated or received blood products in the previous month
  • Someone who donated or received a tissue or organ transplant in the previous month
  • Someone who has had occupational exposure to WNV (in a laboratory or through contact with infected animals)
    
    
• When taking a history from a suspected WNV patient, determine if the patient received blood transfusions or organs within the 4 weeks preceding symptom onset (if so, serum or tissue samples should be retained for testing). In addition, please ask about and report any history of blood or organ donation within 2 weeks of symptom onset for persons with suspected WNV infection. Prompt reporting of these cases will facilitate follow-up including withdrawal of potentially infected blood components.

Counsel patients on ways to prevent mosquito bites, especially those possibly at higher risk for severe disease such as the elderly, persons with immune deficiency, and those with diabetes. These personal protection measures include:
Using insect repellents containing DEET, picaridin, lemon eucalyptus oil, or IR3535.
Taking special care when outdoors at dusk and dawn, when mosquitoes are most active.
Asking families to check screen doors and windows for openings that might allow mosquitoes indoors, and repair screens if needed.
Advise patients to decrease standing water to the greatest extent possible, particularly around the home. Mosquitoes can breed in water that is as shallow as an inch. Ways to reduce mosquito breeding include:
Changing the water in bird baths and animal feeding troughs weekly
Emptying out children’s wading pools when not in use
Eliminating other sources of standing water
Tipping over outdoor wheelbarrows, buckets, and children’s toys when not in use so that they do not collect water