A Louisiana resident infected by H5N1 bird flu has died, state authorities there reported Monday, marking the first U.S. death from the disease.
The patient, a person older than 65 years with preexisting conditions, is believed to have handled infected noncommercial and wild birds with the virus, according to the Louisiana Department of Public Health. The person’s name and gender were not disclosed.
The news has confirmed what many experts fear: That if left to spread unabated, the disease has the potential to cause severe illness and death.
“This is an unfortunate reminder that H5N1 retains the ability to cause severe illness and death. It would be wrong to be reassured by the fact that the patient had underlying health conditions,” said Jennifer Nuzzo, director of the Pandemic Center at Brown University in Providence, R.I.
Nuzzo noted that a child in Canada was also critically sickened by the virus but ultimately survived. However, the lengths doctors took to keep the child alive — daily blood transfusions, intubation and extracorporeal membrane oxygenation, a life support technique that temporarily takes over the function of the heart and lungs for patients with severe heart or lung condition — highlight the extraordinary severity of disease the virus is capable of delivering.
“For this reason, we must treat all infections seriously, and work harder to prevent them,” Nuzzo said.
Before H5N1 bird flu virus arrived in North America in 2021, the disease had been recognized as having potential to cause severe disease and death.
H5N1 was first identified in wild geese in China in 1996 and soon spread among birds in Asia, jumping to people on hundreds of occasions along the way. More than half of those known infections were fatal.
But since the outbreak in U.S. dairy herds and poultry, the vast majority of cases have been mild — with most patients and health providers reporting the most common symptoms as conjunctivitis and mild respiratory distress.
According to the the Centers for Disease Control and Prevention, 66 people in the U.S. have been infected by the virus — and almost all of them were exposed from their jobs working with infected dairy cows or poultry. Only two cases were acquired via an unknown source, including a child in California’s Alameda County.
So far, the only severe case has been the fatality in Louisiana.
In a statement, the CDC said the risk to the public remains low.
Yohishiro Kawaoka, a virologist at the University of Wisconsin-Madison and the University of Tokyo, said the the death “highlights the need for vigilance in avoiding contact with the virus wherever possible.”
At the same time, however, Kawaoka said it was “important to note that the individual was over 65 and had underlying health conditions, which may have contributed to the severity of the illness.”
He said the greatest risk comes from strains circulating in cattle populations.
The virus has been detected in more than 900 dairy herds nationwide, and 701 in California.
Richard Webby, of the World Health Organization, said local, state and federal wildlife and health officials need to be “sampling more birds, more exposed people and learning as much as we can about this virus and where its headed.”
“We also need to ensure the public health testing and treatment capacity is where it should be at. Although a virus that is still poorly infectious to humans, we shouldn’t forget the threat,” said Webby, who directs WHO’s Collaborating Center for Studies on the Ecology of Influenza in Animals and Birds.
There is no evidence the virus has acquired the ability to transmit between people. However researchers say the more opportunities it has to move unchecked throughout the environment and into people, the more chances it has to develop the mutations it needs to do that.
Rick Bright, a virologist and the former head of the U.S. Biomedical Advanced Research and Development Authority, said the Lousiana victim’s medical condition and age are critical factors to consider when evaluating the potential for this disease to cause harm.
“It’s important to understand that almost every American over 50, especially over 65, is easily categorized as having underlying medical conditions,” he said.
Bright voiced concern that the virus may be changing so quickly that it could outpace traditional vaccine development and technologies.
“The CDC will hopefully look carefully at this case to consider updating the risk assessment and the vaccine composition,” he said, underscoring the need for local, state and federal agencies to release genetic sequencing data about this case and the birds the person was exposed to.
