Hong Kong health officials investigating two imported H7N9 influenza from mainland China have found poultry exposures for both patients, as new details emerged about a family connection between China's two newest cases, a father and son from Zhejiang province.
Updates on Hong Kong's cases were provided today during a pandemic preparedness steering committee meeting called by Ko Wing-man, MBBS, Hong Kong's secretary for food and health, according to a government press release.
Hospital officials told the group that the first patient, a 36-year-old woman, is still hospitalized, and her condition has been upgraded from critical to serious. Her fever has subsided and she no longer needs extracorporeal membrane oxygenation (ECMO) treatment. The second patient, an 80-year-old man, is still hospitalized in an isolation unit in stable condition and has a slight fever.
So far none of the close contacts of the two patients have tested positive for H7N9 infection. Five of the woman's close contacts and 19 of the man's are currently or will be in quarantine, according to the statement.
From today's reports, the steering committee concluded that the two cases are sporadic imported cases.
Health officials today traveled to Shenzhen, where the two patients had traveled from before they were diagnosed with H7N9 in Hong Kong, to meet with local and national health officials from the mainland.
Investigators found that the woman may have visited a residential unit in Shenzhen's Longgang district and handled live poultry. However, Hong Kong officials said the woman is unable to clearly identify the source of the poultry. The second patient's family bought and cooked a slaughtered chicken from a market in Fuyong Town in Shenzhen, the statement said, adding that the man did not visit the live poultry market or have direct contact with live poultry.
Mainland authorities have tested poultry samples, but so far none have been positive for the virus. Hong Kong officials said they and Guangdong officials view the source of the infection as inconclusive so far. On Dec 3 as part of its response Hong Kong suspended imports of live poultry from farms in Shenzhen.
Cases in father and son
In other developments, the family connection between Zhejiang province's two latest H7N9 patients was revealed on Dec 7 in a report in Chinese from Xinhua, China's state news agency. Infectious disease news blogs flagged the report over the weekend.
According to the machine translation, the 30-year-old man whose case was first announced on Dec 5 is the son of the 57-year-old man whose illness was first announced at the end of November.
Both patients are hospitalized and in isolation. The father is in critical condition, and his son is in stable condition. The family kept six chickens, and the father's medical team believes the birds are probably the source of the virus, according to the Xinhua report.
Global health officials have said H7N9 virus doesn't appear to spread easily from person-to-person, but family clusters of cases aren't surprising in view of common exposures or close contact.
Dec 9 Hong Kong government press release
Dec 7 Xinhua (in Chinese) story