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Sci­en­tists: New strain of swine flu spread­ing

- By Mike Ives Mike Ives is a New York Times writer. Infectious Diseases · Coronavirus (COVID-19) · Health Conditions · Hong Kong · Beijing · United Kingdom · Proceedings of the National Academy of Sciences of the United States of America · United States National Academy of Sciences · Ian Brown · Animal and Plant Health Agency

HONG KONG — A new strain of the H1N1 swine flu virus is spread­ing silently in work­ers on pig farms in China and should be “ur­gently” con­trolled to avoid an­other pan­demic, a team of sci­en­tists says in a new study.

H1N1 is highly trans­mis­si­ble and spread around the world in 2009, killing about 285,000 peo­ple and mor­ph­ing into sea­sonal flu.

The newer strain, known as G4 EA H1N1, has been com­mon on China’s pig farms since 2016 and repli­cates ef­fi­ciently in hu­man air­ways, ac­cord­ing to the study pub­lished Mon­day. So far, it has in­fected some peo­ple with­out caus­ing dis­ease, but health ex­perts fear that could change with­out warn­ing.

“G4 viruses have all the es­sen­tial hall­marks of a can­di­date pan­demic virus,” the study said, adding that con­trol­ling the spread in pigs and closely mon­i­tor­ing hu­man pop­u­la­tions “should be ur­gently im­ple­mented.”

The study, pub­lished on­line in the jour­nal Pro­ceed­ings of the Na­tional Academy of Sciences, is based on the sur­veil­lance of pigs in 10 Chi­nese prov­inces from 2011 to 2018. In the last three years of the study, re­searchers col­lected 338 blood sam­ples from work­ers on 15 pig farms and 230 from peo­ple in nearby house­holds.

The study found that 10.4% of the work­ers and 4.4% of the others tested pos­i­tive for an­ti­bod­ies to G4 EA H1N1, and that work­ers be­tween the ages of 18 and 35 tested pos­i­tive at a higher rate: 20.5%.

Pre­dict­ing risk is not a pre­cise sci­ence, but close attention to the virus would be ad­vis­able, said Ian Brown, head of the vi­rol­ogy de­part­ment at Bri­tain’s An­i­mal and Plant Health Agency and one of two sci­en­tists who re­viewed the pa­per be­fore it was pub­lished.

“It may be that with fur­ther change in the virus it could be­come more ag­gres­sive in peo­ple much as SARS­COV­2 has done,” Brown said in an email Tues­day, re­fer­ring to the new coro­n­avirus.

The study was sent for re­view in early De­cem­ber, weeks be­fore the coro­n­avirus out­break in the Chi­nese city of Wuhan be­gan mak­ing global head­lines.

 ?? Greg Baker / AFP via Getty Images ?? The newer strain, known as G4 EA H1N1, has been com­mon on China’s pig farms like this one in He­nan prov­ince since 2016.
Greg Baker / AFP via Getty Images The newer strain, known as G4 EA H1N1, has been com­mon on China’s pig farms like this one in He­nan prov­ince since 2016.

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