Virus you’ve never heard of infected record number of Americans this year

A deadly virus few people know exists is wreaking havoc in intensive care units and children’s hospitals, doctors warn.

High rates of Covid, flu, and even RSV over the winter led to hospitals flooding over the winter in a situation called a “triple-demic.”

But cases of human metapneumovirus (HMPV), which can cause bronchitis and pneumonia, shot to record levels in the spring, according to the Centers for Disease Control and Prevention’s respiratory virus surveillance systems.

It may partly explain why so many people have tested negative for flu and Covid in recent months despite showing symptoms.

Dr. John Williams, a pediatrician at the University of Pittsburgh who has spent his career researching vaccines and treatments for HMPV, said HMPV is “the most important virus you’ve never heard of.”

Dr. Williams said that, alongside flu and RSV, HMPV was one of the viruses most likely to hospitalize and even kill people.

This year in mid-March, 11 percent of cases tested were positive for HMPV. This is 36 percent higher than the average pre-pandemic seasonal peak of seven percent.

Most patients who have contracted the virus probably did so unknowingly, as people are only tested for it in the hospital or emergency room.

Due to a lack of testing, the number of people who become infected or die from HMPV each year is not known, but test positivity – the swabs that are tested – is increasing.

And blood tests show that most children have had it by the age of five.

There are no vaccines or drugs to treat HMPV.

It causes cough, runny nose, sore throat and fever. In severe cases, patients may have difficulty breathing, develop bronchitis or pneumonia.

As with the flu, infants and the elderly are most at risk because their immune systems are still developing or deteriorating.

HMPV is spread through direct or close contact with an infected person, such as coughing, shaking hands, sneezing, or touching contaminated objects or surfaces.

One study found it was the second most common cause of respiratory infections in children after respiratory syncytial virus (RSV), which usually causes mild, common cold symptoms but hits infants and older adults harder.

HMPV and RSV belong to the Pneumoviridae family.

A study in New York found that it was just as common in hospitalized elderly patients as RSV and the flu.

All three infections can cause fatal cases of pneumonia in seniors.

Leigh Davison, 59, came to HMPV in early April after attending a family gathering.

Her symptoms were so bad that she could no longer talk on the phone.

She said CNN: ‘I couldn’t come up with more than a few words. I started coughing profusely, violently to the point where I literally almost vomited.”

She was certain she had Covid but after six negative rapid tests became nervous about pneumonia as she is immunocompromised.

But she had a clear x-ray from a radiology clinic. She had to see her doctor, who sent her to an ER room for further testing, which revealed that she had HMPV.

Mrs. Davison said, “I was like ‘What? Because it sounds really awful.’

The virus gave her severe bronchitis and she was hospitalized for observation.

She was ill for about a month and then got better.

Of the respiratory infections she’s had in her life, HMPV was “the worst I’ve ever experienced,” she said.

HMPV was discovered in 2001 by Dutch researchers from samples of children in the Netherlands with unexplained respiratory infections.

Some were seriously ill and had to be put on a ventilator, but did not test positive for pathogens.

The scientists looked at the genes of the virus and saw that it was closely related to the avian metapneumovirus, which infects birds.

The new virus was named human metapneumovirus. The researchers think it jumped from birds to humans and then evolved.

Dr. John Williams, a pediatrician at the University of Pittsburgh who has spent his career researching vaccines and treatments for HMPV, said HMPV is “the most important virus you’ve never heard of.”

A 2020 study estimated that there were more than 16 million HMPV infections, more than 600,000 hospitalizations, and more than 16,000 deaths in children under five in 2018.

Meanwhile, Covid shotmaker Moderna recently completed an early study of an mRNA vaccine against HMPV and parainfluenza.

Covid lockdowns have also meant that people’s immune systems are generally a lot weaker due to a lack of social interaction and natural exposure to pathogens.

A study published by the NIH suggested that the mortality rate for HMPV was 43 percent after 100 days.

Researchers estimate that 10 to 12 percent of childhood respiratory illnesses are related to HMPV.