CDC: Testing Recommendations for Persons with possible infection with Avian Influenza A (H7N9) virus in the United States

• Page last reviewed: January 24, 2014
• Page last updated: January 24, 2014

• Content source: Centers for Disease Control and Prevention, National Center for Immunization and Respiratory Diseases (NCIRD)

Patients who meet both the clinical and exposure criteria described below should be tested for avian influenza A (H7N9) virus infection by reverse-transcription polymerase chain reaction (RT-PCR) assay using H7-specific primers and probes. Decisions on diagnostic testing for influenza using RT-PCR should be made using available clinical and epidemiologic information, and additional persons in whom clinicians suspect avian influenza A (H7N9) virus infection also should be tested. For more information on laboratory testing of persons under investigation for avian influenza A (H7N9) virus infection, please see Information for Health Professionals and Laboratorians. Guidance on testing, treatment, and infection control will be updated by CDC as more information becomes available.

Clinical Illness Criteria

1. Patients with new-onset severe acute respiratory illness requiring hospitalization (i.e., illness of suspected infectious etiology that is severe enough to require inpatient medical care in the judgment of the treating clinician).
   AND
2. Patients for whom no alternative infectious etiology is identified.

Exposure Criteria

1. Patients with recent travel (within 10 days of illness onset) to areas where human cases of avian influenza A (H7N9) virus infection have recently become infected¹ or where avian influenza A (H7N9) viruses are known to be circulating in animals².
   OR
2. Patients who have had recent close contact (within 10 days of illness onset) with suspected³ or confirmed cases of human infection with avian influenza A (H7N9) virus. Close contact may be regarded as coming within about 6 feet (2 meters) or within the room or care area of a person with a suspected or confirmed case while the person was ill (beginning 1 day prior to illness onset and continuing until resolution of illness). Close contacts include healthcare personnel providing care for a person with a suspected or confirmed case, family members of a person with a suspected or confirmed case, persons who lived with or stayed overnight with a person with a suspected or confirmed case, and others who have had similar close physical contact, especially without the use of respiratory protection.
   OR
3. Persons with an unprotected exposure to avian influenza A (H7N9) virus in a laboratory setting.
   
   ¹As of January 23, 2014, mainland China is the only country where human cases of avian influenza A (H7N9) virus infection have recently (within the past 24 months) become infected.
   
   ²As of January 23, 2014, mainland China is the only country where avian influenza A (H7N9) viruses are known to be circulating in animals.
   
   ³Patients suspected of having infection with avian influenza A (H7N9) virus can include probable cases, cases under investigation for infection with avian influenza A (H7N9) virus, and other patients for whom available clinical and epidemiologic information support a diagnosis of infection with avian influenza A (H7N9) virus.

State health departments are encouraged to investigate potential human cases of avian influenza A (H5N1) virus infection and should notify CDC within 24 hours of identifying a probable or confirmed case of novel influenza A virus infection, including avian influenza A (H5N1) virus infection, and avian influenza A (H7N9) virus.

http://www.cdc.gov/flu/avianflu/h7n9/testing.htm