The Centre for Health Protection (CHP), Hong Kong, SAR, China and the National Health and Family Planning Commission (NHFPC) of China recently notified the World Health Organization (WHO) of two additional laboratory-confirmed cases of human infection with avian influenza A(H7N9) virus.
An 85-year-old woman from Hong Kong with underlying medical conditions traveled to Dongguan, Guangdong Province, from April 4 to April 5 and stayed with a relative who raised chickens. The patient also visited a wet market located near her relatives’ home and helped in slaughtering chickens on April 4. She returned to Hong Kong on April 5, became ill on April 11 and was admitted to a hospital on April 13. She is currently in critical condition. The CHP is currently conducting investigations and contact tracing.
A 52-year-old man from Changzhou City, Jiangsu Province became ill on April 10, was admitted to a hospital on April 13 and is currently in severe condition.
The Chinese government has taken the following surveillance and control measures: strengthen surveillance and situation analysis; reinforce case management and treatment; and conduct risk communication with the public and release information.
The previous report of avian influenza A(H7N9) virus detection in live poultry exported from mainland China to Hong Kong SAR shows the potential for the virus to spread through movement of live poultry, at this time there is no indication that international spread of avian influenza A(H7N9) has occurred. However as the virus infection does not cause signs of disease in poultry, continued surveillance is needed. Further sporadic human cases of avian influenza A(H7N9) infection are expected in affected and possibly neighboring areas.
Should human cases from affected areas travel internationally, their infection may be detected in another country during or after arrival. If this were to occur, community level spread is unlikely as the virus does not have the ability to transmit easily among humans. Until the virus adapts itself for efficient human-to-human transmission, the risk of ongoing international spread of H7N9 virus by travellers is low.
WHO advises that travelers to countries with known outbreaks of avian influenza should avoid poultry farms, or contact with animals in live bird markets, or entering areas where poultry may be slaughtered, or contact with any surfaces that appear to be contaminated with feces from poultry or other animals. Travelers should also wash their hands often with soap and water. Travelers should follow good food safety and good food hygiene practices.
WHO does not advise special screening at points of entry with regard to this event, nor does it currently recommend any travel or trade restrictions.
As always, a diagnosis of infection with an avian influenza virus should be considered in individuals who develop severe acute respiratory symptoms while travelling or soon after returning from an area where avian influenza is a concern.
WHO encourages countries to continue strengthening influenza surveillance, including surveillance for severe acute respiratory infections (SARI) and to carefully review any unusual patterns, in order to ensure reporting of human infections under the IHR (2005), and continue national health preparedness actions.