An already bad flu season is causing more havoc across the United States, federal health officials said Friday, and it’s hitting the elderly hardest. But 29 children also have died from influenza, the Centers for Disease Control and Prevention reports.
The nation is only about halfway through this severe season, said CDC director Dr. Tom Frieden, and the worst outcomes are likely to get even worse as those who catch the flu develop complications.
"We expect to see both the number and rates of hospitalization and deaths to rise further," Frieden said.
CDC says 30 states have high influenza activity, up from 24 last week. More than 5,000 people have been sick enough to be hospitalized.
“Forty-eight states reported widespread geographic influenza activity,” CDC says in its weekly influenza report. Widespread activity includes states with moderate and low activity.
Flu is still increasing in some areas, particularly in the West, but overall visits to doctors for flu-like illness appear to be decreasing, Frieden added.
“Between October 1, 2012 and January 12, 2013, 5,249 laboratory-confirmed influenza-associated hospitalizations were reported. This is a rate of 18.8 per 100,000 population,” the CDC says. “More than 40 percent of hospitalized children had no identified underlying medical conditions.”
Influenza is notoriously hard to predict, and the season varies a lot from year to year in its severity. The U.S. has had two fairly mild flu seasons in a row, and people were surprised when the virus started sickening people early this year.
As often happens, the elderly are most at risk. Flu kills anywhere between 3,000 and 49,000 people a year — it varies a lot, the CDC says — and people over 65 are far more likely to die from flu than any other age group. People need to take care to protect the elderly, CDC advises.
So far this year, the rate of hospitalization for flu among those older than 65 has climbed to 82 per 100,000 people — a high rate comparable to recent severe seasons, CDC experts said.
“If you’re around grandma a lot, make sure you are vaccinated,” said CDC spokesman Tom Skinner. “Health care workers need to ensure they are vaccinated.”
The CDC calculates flu season severity based on historical statistics and on a week-by-week basis. During the second week of January, 8.3 percent of all deaths that were reported were from influenza and pneumonia. That's higher than the 7.3 percent normally considered an epidemic for that week.
Deaths also vary a lot. Last year, 34 children died from flu, but in the 2010-2011 flu season 122 died, and when the H1N1 swine flu pandemic hit in 2009-2010, it killed 282 U.S. children.
The early season has caused a run on flu vaccines, and now some areas report shortages. The good news, the CDC says, is that flu vaccine makers have been able to squeeze out 10 million more doses of the flu vaccine than expected, for a total of 145 million doses. As of the week ending Jan. 11, more than 129 million doses had been distributed.
“Providers can get more flu vaccine,” Skinner said. “We’ll direct them to the availability tracking system.”
About a million doses of flu vaccine are distributed every day, health experts said.
Seven different companies make flu vaccine, and the U.S. relies on these private drug companies to help predict which flu strains to put in it and how many doses to make. This year the vaccine protects against the three most common strains of influenza.
It’s made using old and tricky technology — most flu vaccine is grown in chicken eggs, a process that takes months and that is notoriously unpredictable in terms of just how many doses it will provide. Next year some new vaccines will be available — including some that protect against four strains of flu, and a new, next-generation formula made using caterpillar cells and DNA.
The early and harsh season has also raised demand for the antiviral drugs that can treat flu. There are two — Tamiflu, which comes in a capsule or syrup for kids, and Relenza, an inhaled powder. If people take them as soon as symptoms start, these drugs can reduce the severity of infection and perhaps cut off a few days of illness.
Frieden urged high-risk patients, including children, the elderly and those with underlying medical conditions to seek antivirals at the first sign of illness.
Roche, the company that makes Tamiflu, says it’s releasing more of the drug, with the permission of the Food and Drug Administration.
“To ensure continuous supply of Tamiflu (oseltamivir phosphate), Genentech has worked with the FDA to release our own reserve stock of Tamiflu,” the company said in a statement.
The CDC also notes that only 29 percent of people tested for flu-like illness actually have influenza — the rest have some other infection. There are exceptions — in the Midwest region, more than half of those showing up at clinics actually have influenza. Many viruses look like flu, and a strain of stomach virus called norovirus is also circulating.
The bottom line, Frieden said, is that people need to take this flu season seriously, seek vaccines and antivirals and do their best to prevent infection.
"Even when you're halfway through the season, that means that you've got half of the season left," he said.