The First US Bird Flu Death Is a Stark Warning

Nuzzo says it’s possible that the Louisiana patient’s pre-existing health conditions contributed to the severity of their illness, but also points to the case of a teenager in Canada who was hospitalized with bird flu in November.

The 13-year-old girl was first seen in an emergency department in British Columbia with fever and conjunctivitis in both eyes. He was discharged home without treatment and later developed cough, vomiting and diarrhoea. A few days later he returned to the emergency department with shortness of breath. He was admitted to the pediatric intensive care unit and went into respiratory failure but eventually recovered after treatment. According to a The case report has been published New England Journal of MedicineThe girl had a history of mild asthma and an elevated body-mass index. How he contracted the virus is unknown.

“What this tells us is that we have no idea who is going to develop mild illness and who is going to develop severe illness, and because of that, we have to take these infections very seriously,” Nuzzo said. “We should not assume that all future infections will be mild.”

There is another source that may explain the severity of the Louisiana and British Columbia cases. Virus samples from both patients showed some similarities. For one, both were infected with the same subtype of H5N1 called D1.1, which is the same type of virus found in wild birds and poultry. This is different from the B3.13 subtype, which is dominant in dairy cows.

“Right now, the question is, is this a more serious strain than the dairy cattle strain?” said Benjamin Anderson, assistant professor of environmental and global health at the University of Florida. So far, scientists don’t have enough data to know for sure. Some chicken farm workers in Washington tested positive for the D1.1 subtype, but those individuals had mild symptoms and did not require hospitalization.

“In the case of the Louisiana infection, we know the person had comorbidities. We know the person was an older person. Those are factors that contribute to an already more severe outcome in respiratory infections,” Anderson said.

In the Louisiana and British Columbia cases, there is evidence that the virus can cause more severe illness in both patients.

A CDC report in late December The virus taken from the Louisiana patient was found to have genetic mutations that allowed it to increase its ability to infect the upper respiratory tract of humans. The report states that the observed changes were generated by replication of the virus throughout the patient’s illness rather than infection during the infection, meaning that the mutations were not present in the birds to which the person was exposed.

This is written New England Journal of MedicineThe team caring for the Canadian teenager also described “alarming” mutations found in her viral samples. These changes allow the virus to more easily bind to and enter human respiratory cells.

In the past, bird flu has rarely been transmitted from person to person, but scientists worry about a situation where the virus acquires mutations that make it more likely to infect humans.

For now, people who work with or have recreational exposure to birds, poultry or cattle are at higher risk of getting bird flu. To prevent illness, health officials recommend avoiding direct contact with wild birds and other animals suspected of being infected with the bird flu virus.