The Centers for Disease Control recently issued updated guidance for patients who 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.
Patients with new-onset severe acute respiratory illness requiring hospitalization and patients for whom no alternative infectious etiology is identified should be considered for the H7N9 testing. Patients with a travel history to areas where human cases of avian influenza A (H7N9) virus infection is known or where avian influenza A (H7N9) viruses are known to be circulating in animals should also be tested.
Close contact with a person with a suspected or confirmed case of H7N9 should also be tested for the strain. This includes healthcare personnel providing care for a person with a suspected or confirmed case, family members, 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.
As 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. China is also the only country where this virus is currently known to be circulating in animals, according to the CDC.
State health departments are requested to 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.
The CDC will update guidance on testing, treatment, and infection control for this emerging influenza as more data becomes available.