One possible sign for the US is that Chile’s flu hospitalizations were the highest in three years – but the vaccine was 49% effective against hospitalizations

Advertisement

One possible sign for the US is that Chile's flu hospitalizations were the highest in three years - but the vaccine was 49% effective against hospitalizations



CNN

A possible warning sign for the US and other countries in the northern hemisphere, Chile’s 2022 flu season started much earlier than usual and brought with it more hospitalizations than during the pandemic, but the vaccine’s effectiveness against hospitalizations has been estimated at nearly 50%, according to a new one Study published by the US Centers for Disease Control and Prevention.

Researchers look to the southern hemisphere when trying to predict what the North American flu season might be like, and they found that the southern season was particularly bad this year.

I
In the study, published Thursday in the CDC’s Morbidity and Mortality Weekly Report, researchers found that flu numbers in Chile were at epidemic levels for the first six weeks of the year — much earlier than in 2017, 2018, or 2019, when the Flu season started in April or May. This year’s numbers declined in weeks seven through 17 before rising back to epidemic levels in May and peaking in June.

Chile’s flu hospitalization rates this year were “substantially higher” than in 2020 and 2021, the researchers say. These pandemic years have been marked by particularly low levels of viral disease globally as a result of measures taken to contain Covid-19, and experts have warned that the lifting of these measures – and reduced exposure to viruses during the pandemic – will push infection numbers back up .

However, compared to the years leading up to the 2017-19 pandemic, this year’s flu hospitalization rates in Chile were “substantially lower.” This is partly due to the vaccination of more than 92% of residents who were preferred because of their age or underlying medical condition, a group that made up 41% of the total population.

The flu vaccine used in Chile, which contained a match to the dominant A(H3N2) virus, was found to be 49% effective in preventing hospitalizations. The shot used in the Northern Hemisphere contains the same group of viruses and the same antigen as the Southern Hemisphere vaccine, the researchers said, so it could be similarly effective if the same virus is dominant.

A flu shot can prevent infection, and for those who do get the flu, the shot can reduce the severity of the disease and the risk of hospitalization.

The researchers say their findings should reinforce the need to prepare for an “atypical season” and they urge health officials to encourage everyone to get vaccinated and avoid close contact with sick people.

According to the US Centers for Disease Control and Prevention, flu activity in the US has already picked up about a month earlier than usual. Overall respiratory disease activity was “very high” in Washington, DC and “high” in seven states: Alabama, Georgia, Louisiana, New York, South Carolina, Tennessee and Texas.

More than 4% of lab tests were positive for flu by the second week of October, more than doubling in the past two weeks but not yet reaching the highest positivity rate of last year. Hospitalizations for flu are also increasing, but are not yet at the peak of last year.

So far, flu shot rates in the US are lower than at this point in the season in recent years — about 116 million doses of flu vaccine have been distributed, compared to 129 million at this point last year and 141 million a year earlier in 2021.

dr Nipunie Rajapakse, a pediatric infectious disease specialist at the Mayo Clinic Children’s Center, told CNN on Thursday that people should get vaccinated against Covid-19 and the flu and try to prevent respiratory illnesses, especially when the hospital admissions are due to RSV and other viruses gain weight .

“It’s even more important to make sure your children and anyone in your family over the age of six months get their flu shots this year because we haven’t seen much influenza in recent years and so everyone is going into this season with less immunity, less protection from previous infections,” said Rajapakse.

You May Also Like