A fourth dairy worker in the U.S. has tested positive for the H5N1 bird flu. The unnamed worker, based in Colorado, experienced mild symptoms comparable to conjunctivitis, as reported by state health authorities. This development comes as H5N1 has spread to 139 cattle herds across 12 U.S. states, including 27 herds in Colorado.
Since it first emerged in humans in the late 1990s, H5N1 has shown a high lethality rate of around 50%. However, the recent U.S. cases have been notably mild. The U.S. government recently announced a $176 million investment in Moderna for mRNA vaccine development against bird flu, amid concerns about possible human-to-human transmission.
Despite the potential dangers, the U.S. Centers for Disease Control (CDC) maintains that the public health risk from H5N1 remains low. The CDC urges those in close contact with livestock to report any symptoms. Meanwhile, criticisms have emerged regarding the agency’s transparency in handling these cases.
Efforts to contain the outbreak include state-level surveillance and federal financial incentives for farmers to enhance protective measures. The U.S. government has allocated up to $28,000 per farm to cover the costs of protective equipment and testing over the next four months.