Person-to-person transmission of avian influenza A (H7N9) virus between 2 unrelated individuals has been reported in a hospital in China, according to a published report in The BMJ.
The report describes 2 patients who shared the same ward in a district hospital in Zhejiang Province, China, in February 2015.
The first patient was a 49-year-old man who became ill after buying 2 chickens from a live poultry market for the wedding ceremony of his elder daughter. He developed a fever, cough, and sore throat and was admitted to a district hospital on February 18. He was diagnosed with H7N9 virus on February 24 and was admitted to a specialist hospital ward with intensive care facilities. He died of multi-organ failure on April 20.
The second patient, a 57-year-old man with a history of chronic lung disease (COPD), developed flu-like symptoms after staying on the same ward of the district hospital as the index case for 5 days (February 18-23). He was diagnosed with H7N9 virus on February 25 and died of respiratory failure on March 2.
A total of 38 close contacts of both cases, including family members and health workers, were tested for the virus. Two samples taken from the chickens purchased by the index patient as well as 5 of 11 samples from the live poultry market he visited were positive for H7N9 virus. The second patient had no history of poultry exposure for 15 days prior to his illness. Samples from his home, from chickens raised by his neighbors, and from a local chicken farm were all negative for H7N9 virus.
The genetic sequence of H7N9 virus from the second patient was nearly identical to that from the index patient, and genetically similar to the virus samples taken from the live poultry market visited by the index patient.
The researchers noted that they cannot completely rule out an unidentified environmental exposure that might explain the H7N9 infection in the second patient. However, because no other common exposure was identified, they said “it seems most likely that the H7N9 virus was transmitted from the index case to the second case during their stay on the same ward.”
The researchers added that these results “should raise our concern about the increasing threat to public health” and they called for better training and hospital hygiene as well as enhanced surveillance of both patients with influenza-like illness in hospitals and chickens in live poultry markets.