National and international information

• National outbreak information (CDC)
• The World Health Organization increased the pandemic alert level from 3 to 4 on April 27, 2009. Level 4 is characterized by verified human-to-human transmission of an animal or human-animal influenza reassortant virus able to cause "community-level outbreaks." The change to a higher phase of pandemic alert indicates that the likelihood of a pandemic has increased, but not that a pandemic is inevitable. Information from WHO is available.
• Yesterday, CDC issued a travel health warning for US travelers to avoid all nonessential travel to Mexico.

Diagnosis and testing

• Triage: Who to evaluate - Public Health recommends that clinicians use their clinical judgment in deciding whom to assess for swine influenza virus infection. Evaluation is not necessarily indicated for all ill persons who have traveled to an area where swine influenza transmission is occurring. Rather, triage should consider the extent of swine flu transmission in the area visited (consult CDC website or with Public Health), clinical symptoms and severity of illness, the potential for severe complications of influenza infection, and the potential for the patient to spread infection to those at high risk for severe complications.
  
  
• Criteria for testing - Clinicians should consider the possibility of swine influenza virus infections in patients presenting with acute febrile respiratory illness. King County residents may be tested for swine influenza infection at the Washington Department of Health Public Laboratory after consultation with Public Health – Seattle & King County at 206 296-4774. Testing is currently recommended for patients suspected of having swine flu infection defined by the following criteria:
  • Persons with acute febrile respiratory illness and one of the following risk factors in the 7 days prior to illness onset:
    • Travel in Mexico or other area where area where one or more cases of swine influenza have been reported or
    • Contact with a person with an acute febrile respiratory illness who had traveled in the 7 days prior to their illness onset to Mexico or other area where one or more cases of swine influenza have been reported, or
    • Contact with a confirmed or probable case of swine influenza

In addition, Public Health is requesting that health care providers and clinical laboratories submit specimens to WA State Public Health Laboratory from patients meeting the following criteria for surveillance purposes even when not suspected to have swine influenza for surveillance purposes:

Persons hospitalized with severe respiratory illness (i.e., fever >37.8 [100°F] plus shortness of breath, hypoxia, or radiographic evidence of pneumonia) that may be due to influenza; or

Unexplained deaths in people less than 50 years of age that appear due to severe respiratory illness, respiratory failure, or pneumonia.

• Specimen collection
  • After consultation with Public Health (call 206-296-4774, 24/7), send the specimen to the WA State Public Health Lab (PHL). Consult with Public Health by calling 206-296-4774 (24/7) to report suspected cases and arrange for testing of the specimen.
  • A nasopharyngeal swab placed in viral transport media should be collected as soon as possible after illness onset for swine flu testing at the public health laboratory. (At this time the methodology used at the PHL is not approved for use on nasal wash or throat swabs. Testing of these specimens may be considered on a case-by-case basis only after consultation with Public Health when a nasal swab is not available). Additional specimens may be obtained for testing for influenza and other potential etiologies at your routine clinical laboratory (NP swab, nasal wash, etc) at the discretion of the treating clinicians.
  • Observe infection control precautions including use of appropriate PPE when obtaining specimens (see below).
  • Specimens should be collected using swabs with a synthetic tip (e.g., polyester, rayon or Dacron®) and an aluminum or plastic shaft. Swabs with cotton tips and wooden shafts are not recommended. Specimens collected with swabs made of calcium alginate are not acceptable. NP swab specimens should be placed into sterile viral transport media (VTM such as M4RT or the BD Universal Viral Transport System) and immediately placed on ice or cold packs or at 4°C (refrigerator) for transport to the laboratory.
  • Keep specimens cold and ship so specimens arrive at PHL within 72 hours of collection. Include virology form (PDF)
  • Ship specimens to: Attn: PHL Virology Laboratory 1610 NE 150th Street Shoreline, WA 98155
    
    
• Infection control in health care settings
  
  • A combination of standard, droplet, contact and airborne infection control measures are recommended.
  • Patients with suspected or confirmed case-status should be placed in a single-patient room with the door kept closed. If available, an airborne infection isolation room. For suctioning, bronchoscopy, or intubation, use a procedure room with negative pressure air handling.
  • The ill person should wear a surgical mask when outside of the patient room, and should be encouraged to wash hands frequently and follow respiratory hygiene practices.
  • Personnel providing care to or collecting clinical specimens from suspected or confirmed cases should use a respirator if available (surgical or procedure mask if respirator not available), and wear disposable non-sterile gloves, gowns, and eye protection (e.g., goggles) to prevent conjunctival exposure.
  • Masks and respirators: Until additional, specific information is available regarding the behavior of this swine influenza A (H1N1), the guidance in the October 2006 "Interim Guidance on Planning for the Use of Surgical Masks and Respirators in Healthcare Settings during an Influenza Pandemic" should be used. These interim recommendations will be updated as additional information becomes available:
    • Personnel engaged in aerosol generating activities (e.g., collection of clinical specimens, endotracheal intubation, nebulizer treatment, bronchoscopy, and resuscitation involving emergency intubation or cardiac pulmonary resuscitation) for suspected or confirmed swine influenza A (H1N1) cases should wear a fit-tested disposable N95 respirator.
    • Pending clarification of transmission patterns for this virus, personnel providing direct patient care for suspected or confirmed swine influenza A (H1N1) cases should wear a fit-tested disposable N95 respirator when entering the patient room.
  • Persons with swine influenza A (H1N1) virus infection should be considered potentially contagious for up to 7 days following illness onset. Persons who continue to be ill longer than 7 days after illness onset should be considered potentially contagious until symptoms have resolved. Children, especially younger children, and possibly persons with immune system compromise might be contagious for longer periods.
  • Non-hospitalized ill persons who are a confirmed or suspected case of swine influenza A (H1N1) virus infection are recommended to stay at home (voluntary isolation) for at least the first 7 days after illness onset except to seek medical care
  • See www.cdc.gov/swineflu/guidance for current CDC guidance on infection control, biosafety guidelines for laboratory workers, recommendations for facemask and respirator use in certain community settings where swine influenza A (H1N1) virus transmission has been detected, guidelines for management of a swine flu patient in the home, and more.
    
    
• Treatment and prophylaxis
  • CDC currently recommends empiric antiviral treatment for any ill person suspected to have swine influenza A (H1N1) virus infection. Public Health recommends clinicians also consider the severity of illness, risk for influenza-related complications, and risk for transmission to others when making treatment decisions.
  • Antiviral treatment for a confirmed or suspected case of swine influenza virus infection may include either oseltamivir or zanamavir, with no preference given at this time. Recommendations for use of antivirals may change as data on antiviral susceptibilities become available.
  • Currently in King County, seasonal influenza virus is circulating at low levels. For persons who are severely ill, adding rimantidine or amantidine for coverage of seasonal influenza A (H1N1) should be considered because this strain is resistant to the neuraminidase inhibitors oseltamivir and zanamivir.
  • CDC recommendations for antiviral treatment and prophylaxis of swine influenza, including dosing recommendations.
  • Also see: CDC Recommended Daily Dosage of Seasonal Influenza Antiviral Medications for Treatment and Chemoprophylaxis for the 2008-09 Season --United States.

To subscribe to receive e-mail and/or fax health alerts from Public Health, contact Maybelle Tamura at 206-296-4774 or Maybelle.Tamura@kingcounty.gov