Special Gene Potentially Responsible For Chinese Fatal Infections Of H7N9 Bird Flu Disease

The H7N9 strain of bird flu is continuing to spread and take the lives of Chinese citizens, despite government efforts to stem the outbreak. On Tuesday, three more people had died from the avian flu, state news reported, adding to the recent spike of fatalities this year.

Two men, ages 76 and 52, from southern Guangdong province died earlier this week, while another from eastern Jiangsu province passed away over the weekend, bringing the total number of cases to 115, including 25 deaths. The rate at which the flu is spreading is cause for some alarm considering last year’s numbers. In 2013, there were a total of 144 infections and 46 deaths for the entire year, according to Chinese health officials.

According to a report in the Oxford Journals of Clinical Infectious Diseases, the prevalence of the disease among Chinese could be related to a gene that makes them more prone to severe symptoms. Michael Woodhead, a Sydney-based medical journalist, explains in layman’s terms that the IFTM3 gene increases the severity of avian influenza, but is not commonly found in whites, whereas it is in Chinese people. While this does not explain the current surge in cases, it does give a possible explanation for why the disease for the most part is contained in China.

Citing Dr. David Hui of the Chinese University of Hong Kong, Woodhead notes that recent research shows that 70 percent of Chinese patients who had suffered from severe influenza symptoms also had the IFTM3 gene. The gene is associated with having “a six-fold higher risk of severe influenza, and has also been linked to higher influenza mortality,” he notes. The gene may also help explain clusters of families being infected, given that health officials said evidence doesn’t suggest human-to-human transmission.

The World Health Organization says the rise in numbers, for now at least, is consistent with seasonal trends of the disease, rather than virus mutation.

Hong Kong and Chinese local governments have worked to minimize exposure to risk factors, which included culling about 20,000 chickens in Hong Kong that had been imported from a mainland Chinese poultry farm that was found to harbor H7N9.