The Chinese government has withheld from American researchers samples of a virulent strain of avian influenza for over a year, reports the New York Times . And this influenza virus, which prevails in birds called H7N9, is particularly deadly and kills 40% of people who infect it. So far, however, it has not readily spread from poultry to humans and mainly affects only people who work with live poultry, and even then only a small percentage of the number of infected birds. Human-to-human spread, even though this bird flu was extremely small, but Americans essentially have no immunity to the strain and seasonal vaccines have no effect.
Researchers need access to samples from rapid, fatal and unique outbreaks to study mutations to better understand the strain and to formulate or be prepared for vaccines against it. Researchers want to study H7N9 as accurately as possible because of the risk of mutation. Individual influenza strains rapidly turn into deadly and communicable diseases, and new species are unpredictable.
China's alleged refusal to provide samples for more than a year puzzled and angered experts who spoke with the New York Times. . The transfer of samples usually takes months and is based on the rules of the World Health Organization (WHO). The raid could be linked to the trade war of the Trump government, which imposed tariffs on China.
A mutant H7N9 that easily jumped on humans and spread rapidly among humans could lead to a global pandemic. Previous flu pandemics have killed hundreds of thousands to tens of thousands of people and resulted in millions or more hospitalizations. During the pandemic "Spanish flu" from 1
Nearly 1,600 people are infected with H7N9 in six epidemics in China when they arrived in 2013, although half were in the 2016-2017 flu season. Since October 1, 2017, according to CDC, only one case has appeared. The Chinese government claims to have eradicated the disease through a single poultry vaccine campaign. The strain is not fatal to birds.
No fewer than 646,000 people die of seasonal lint globally each year, outside of non-seasonal pandemics. Vaccines reduce the risk of flu in the season by 40% to 60% if the vaccines are close to the prevalent influenza strains. It is particularly effective in reducing children who die from flu-like causes. The vaccines need to be manufactured months before the flu season, and manufacturers rely on other outbreaks in the world as a single predictor.
During the flu season 2017-2018, a 50-year-old strain, H3N2, entered a new virulent form, against which the seasonal vaccine was significantly less effective than in typical years – in some countries as low as 10% effective. This resulted in the highest number of pediatric deaths (179) and the highest rate of hospitalizations for pneumonia and secondary infections in the last decade – about 500 hospital stays per 100,000 people, nearly 50% higher than in the last worst season 2014-2015. (Adult deaths are recorded differently than those of children, and an approximate count occurs long after each season.)
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