It was announced that a person in Louisiana was hospitalized with a severe case of highly pathogenic avian influenza (H5N1 type A). Statement from the Centers for Disease Control and Prevention It was released on Wednesday. This is the first confirmed case of severe avian influenza infection in the United States, and the first human case of avian influenza reported in Louisiana.
The patient did not become infected through working at a poultry or cattle facility, but rather at home. Health officials said they had been exposed to sick and dead birds in backyard poultry flocks. According to the CDC, this is the first confirmed human case of avian influenza linked to a backyard flock in the United States.
There have been 61 confirmed cases of human infection in the current outbreak, all of which have so far been relatively mild. The Louisiana case was confirmed by the CDC on Friday, marking a potential turning point in how health experts view the spread of the virus.
[ Related: Can we prevent a bird flu pandemic in humans? ]
Avian influenza is widespread among wild and captive birds in the United States From 2022 onwards. many Mammals also have The outbreak involving dairy cattle occurred amid a growing agricultural and public health crisis that began in March.
Since 1996, H5N1 has been reported in 23 countries and infected approximately 1,000 people. In past H5N1 outbreaks around the world, severe infections have been more common, human mortality rates have been high, and case fatality rates have been about 50%. In recent months, scientists and public health experts have questioned why the current U.S. bird flu outbreak is causing mild disease among humans, even though it has proven deadly for other mammals. I have openly wondered whether there have been only 100 cases of COVID-19.
Speculative theories include that the mode of exposure dairy workers receive through milking has led to milder cases, that people are being exposed to the virus less, and that smaller infections have gone unreported. , including that previous outbreak fatality rates have been significantly overestimated. The virus had mutated to become less severe in humans. However, these explanations are not sufficient to fully explain what has been observed so far, all have pitfalls, and the question of disease severity remains unresolved. Report from STAT News.
It is difficult to draw conclusions from individual infections. However, with confirmed cases of severe H5N1 infection, it is unlikely that all currently circulating forms of the virus are inherently less dangerous than in the past. It seems there is. At least one variant of bird flu in the United States can cause severe illness in people.
Multiple avian influenza variants are circulating at the same time, and new variants emerge as the virus mutates. CDC investigators have determined through genetic sequencing that the specific virus genotypes present in the Louisiana patients are the same as those detected in wild birds and poultry in the United States and Canada, but also in dairy cows and some The virus was determined to be different from the type detected in poultry. .
Although human infections continue to occur sporadically, human-to-human transmission, the biggest risk factor for an avian influenza pandemic, has not yet been detected. The CDC maintains that the risk of avian influenza to the general public remains low. But the newly confirmed severe infections highlight that farmworkers are not the only ones who can get sick.
Officials say people who have had contact with wild animals or livestock, especially birds, should take precautions to avoid infection. People should avoid contact with sick or dead animals, avoid touching surfaces contaminated by animals suspected of having avian influenza, and those who cannot avoid contact should wear protective equipment. There is.
Each time you avoid infection, A(H5N1) mutates and becomes less easily transmitted between people. Although it is impossible to definitively prevent an avian influenza pandemic, health organizations, farms, and individuals can take steps to minimize the likelihood.
