Return of H7N9 bird flu strain in China

The first human case of avian influenza H7N9 in Hong Kong has just been reported. She is hospitalized and in critical condition. The patient was in Shenzhen last month, and had been in contact with poultry there. The Government has raised the response level from ‘alert’ to ‘serious’ under its preparedness plan for influenza pandemics.

You might recall previous Sitata posts earlier this year on this new strain of bird influenza and how it spread to four provinces in mainland China (Fujian, Jiangxi, Hunan, Henan) in a short period of time; how about half the people who were infected died from this highly lethal virus; and how health authorities had to close the live chicken markets in order to stop the spread of the virus.

Experts from the World Health Organization have noted that this is an “unusually dangerous virus for humans.” Fortunately, there was little human-to-human transmission of this virus and no major international spread. However, several questions remained. For example, it was hard to tell how widely spread this virus was in all the poultry since it did not make the birds sick.

The concern is that the virus might mutate to become more easily transmitted from person to person, which would cause an epidemic.

The person involved in this new case in Hong Kong had contact with poultry, suggesting that the virus has not been entirely eradicated from poultry by the market controls imposed previously by the Chinese Government. As yet there is no evidence of human-to-human transmission of infection associated with this patient, but it is too early to confirm this.

This virus (H7N9) should not be confused with the MERS coronavirus in the Middle East. It is totally unrelated.

For travellers to Hong Kong and China, the best advice is to avoid visiting the live poultry markets and to practice good flu prevention, i.e., wash your hands frequently.