H3N2 flu strain: what you need to know about India’s deadly outbreak

There are two flu viruses — Influenza A and B — that cause seasonal outbreaks at people’s Place.

Influenza A subtypes H1N1 and H3N2 and influenza B lineages Yamagata and Victoria are currently circulating.

H3N2, which was the dominant strain circulating in the United States this year, has been associated with more severe flu seasons.

“So far during the 2022-23 influenza season in the United States, approximately 99% of people hospitalized with influenza had the H3N2 subtype,” says Jennifer HorneyPhD, epidemiologist and founding director of the epidemiology program at the University of Delaware.

Research shows that H3N2 often causes more severe disease in adults 65 and older.

The most common symptoms of flu one cases include cough, congestion, sore throat, fever, headache, chills, body aches, and fatigue.

Influenza A can be treated with supportive care in addition to antivirals such as oseltamivir, baloxavir, peramivir and zanamivir, says Adalja.

According to Horney, flu seasons caused by H3N2 can include more severe illnesses, hospitalizations and deaths.

This is especially true when vaccination coverage is low or the vaccine does not match well with circulating strains, she added.

“A lot of what determines the severity of the flu season has to do with how well the vaccine matches the circulating strain and the percentage of people vaccinated each year overall,” says Horney.

flu virus are constantly changing and the flu vaccine must be updated every year to remain effective.

From time to time, the flu virus mutates in a way that reduces the effectiveness of the shot.

According to Centers for Disaster Control and Prevention (CDC), the flu vaccine is a good match this year – but the coverage in the WE is lower than usual.

A study conducted during the 2017-2018 flu season revealed that only 1.5% of India’s 65,000 adults aged 45 and over had ever received a flu shot, indicating that vaccination coverage in India is likely to be very high. weak, Horney said.

Besides, air pollution – Which one is raised in india — may make flu symptoms worse.

“Respiratory function is worse in a context of high pollution,” says Adalja. “Any respiratory virus would be worse in these kinds of situations.”

As a result, the flu mortality rate is higher in India, especially among the elderly and young children.

That’s “more than double the rate per 100,000 population than in the United States, where we expect between 30,000 and 70,000 flu deaths each year,” Horney said.

India is monitoring an epidemic of influenza A (H3N2) which has caused two deaths. Although the spike in cases occurs a bit later in India’s typical flu season, H3N2 circulates every year. This year’s vaccine is a good match against the circulating strains, and there are effective antivirals that can treat infections caused by H3N2.