What should you know about first human H5N2 case bird flu
By Berkeley Lovelace Jr.
07/06/2024
Is there a new form of bird flu that we should be concerned about?
This week, on Wednesday, the World Health Organization released the first human case of H5N2 form of bird flu, in a 59-year-old man from Mexico who passed away in April.
The incident adds to the growing concern about the danger of spreading bird flu to people, particularly because the victim had no prior background of having been exposed to animals or poultry as per WHO.
The strain is distinct from the bird flu virus known as H5N1 which is spreading in dairy cow herds across the United States and has caused an infection in 3 farm employees.
What is H5N2?
H5N2 is one of many types of avian influenza virus. Is it an imminent health risk for human beings?
The possibility of being exposed to H5 viruses in Mexico isn’t shocking, said Dr. Troy Sutton, an assistant professor of biomedical and veterinary science in Penn State. H5-related viruses are in circulation within wild and domestic birds as well as poultry throughout Mexico from the late 1990s. But unlike other avian flu strains that have led to outbreaks among humans, such as the H1 virus and H3H5 viruses do not infect humans.
They are classified by two kinds of protein found that are found on their surfaces Hemagglutinin, also known as H which plays a vital function in allowing the virus to enter cell lines, as well as neuraminidase or N, which aids in the virus in its spread. A variety of combinations of N and H proteins can be made.
H5N2 is part of a group of viruses that cause bird flu referred to as H5, that mainly affect wild birds. There are nine subtypes that are known to be associated with H5 viruses as per the Centers for Disease Control and Prevention.
It was H5N1 that was found within dairy cows across the U.S. in March, is also part of the H5N1 family. It is frequently connected to highly infectious H5 viruses, which are known as”the “Goose Guangdong lineage” that have been responsible for numerous outbreaks of poultry in the past 20 years, as well as sporadic infections in humans, according to Sutton.
H5N1 has afflicted people in 23 countries from 1997, according to CDC and has caused fatal pneumonia and deaths in around 50 percent of cases.
“They are a separate lineage with a separate history and a separate sort of story around the disease they cause,” Sutton stated “They are a separate lineage with a distinct history.”of the H5N2 and H5N1 virus.
Are people worried?
A patient from Mexico was bedridden for a few weeks prior to beginning to show signs of illness.
According to WHO according to WHO, on April 17 the patient developed vomiting, nausea, fever as well as shortness of breath along with general malaise. The following week 24 April, he went to admitted to the hospital and died the same day.
Sutton stated that it’s crucial to keep in mind that the patient was suffering from multiple medical conditions which could have contributed to the infection.
“The person may have already been quite sick,” Sutton explained. “That changes the calculation a little bit more than, say, a healthy farm worker getting infected.”
The WHO confirmed that no other cases were identified during its investigation. Out of the 17 people that were identified and monitored in that hospital, where patient passed away one of them reported a runny nose.
Experts do not know why the man was infected by the virus since he was not subjected to chickens or other animals. If the man was infected by another human, this implies that there could be other cases that aren’t known to be present.
“It is concerning that a new virus subtype has infected a human,” Sutton stated.
Doctor. Michael Osterholm, an expert in infectious diseases of The University of Minnesota, said that human-to-human transmission of the disease is unlikely. “They likely picked it up from the same place.”
It has been determined that H5N2 which affected the man is not a pathogenic virus, which means it’s unlikely to cause serious disease, according to Osterholm.
“There’s the high and low path. And the high path is characterized by genetic modifications. It is more likely to lead to serious illnesses,” Osterholm said. “And the readily transmitted low path oftentimes can infect any number of animal species with little or no symptoms.”
What are scientists looking to learn
Doctor. Paul Offit, an expert in infectious diseases and the Director of the Vaccine Education Center at the Children’s Hospital of Philadelphia, explained that the primary concern among experts is whether or not the H5N2 virus has changed in a manner that has made it more prone to spreading to humans.
H5 viruses in general they struggle to get into people’s bodies because the receptors for cells they are targeting in birds are very different from those in us.
This is often the reason people get infected with H5 viruses after direct contact with birds and other poultry and not with other human beings.
H5N1 that has developed to cause human infections rarely, has not caused widespread transmission from human to human the doctor said.
“The fact that it is H5N2, as compared to H5N1, I don’t think is meaningful in terms of representing something that is more likely to be associated with a pandemic,” Offit stated. “If the virus can’t reproduce itself well in the upper respiratory tract, it’s not going to be able to spread easily from human to human.”
Sutton stated that researchers must conduct a more genetic analysis of H5N2 viruses which affected the Mexican man, before they can to determine if the virus poses an issue for humans.
“Until we have that information, it’s really hard to draw a lot of conclusions.”
Osterholm claimed that H5N1 is actually the one we must focus on “laser focused” on.
The H5N1 virus has been spotted taking away dairy cattle across the U.S., infecting at minimum 84 herds across nine states as per the U.S. Department of Agriculture which raises possibilities that the virus may develop mutations that permit it to infect humans.
Berkeley Lovelace Jr. is an expert in medical and health reporting at NBC News. He is a reporter for all aspects of the Food and Drug Administration, with a concentration on Covid vaccines as well as prescription drug pricing and health medical care. He has previously covered pharmaceutical and biotech industry for CNBC.
