Despite some shortages, people seeking a vaccine should be able to get one. 2013 flu epidemic?

This flu season struck hard about a month earlier than usual. But despite all those news reports about overcrowded emergency rooms, it’s too soon to say whether it will be worse than normal.

In fact, federal health officials said last week it may already have peaked.


“Only time will tell,” Centers for Disease Control and Prevention Director Thomas Frieden said on a conference call with reporters.

Following a week of reports about influenza vaccine shortages and jam-packed hospitals, CDC officials added a dose of perspective. They said the number of states reporting “high” levels of flu activity has actually dropped from 29 to 24 — although that could still change.

There’s been an uptick in states reporting some moderate activity, and the virus has spread nationwide — a total of 47 states reported regional or widespread outbreaks.

“It’s just about everywhere,” said Jeffrey Shaman, a professor at Columbia University’s Mailman School of Public Health. “It’s a very intense transmission season — probably the most intense we’ve seen in a decade.” That means the virus spreads aggressively — but experts are still divided on whether this year’s flu is especially dangerous. It’s still too early to know the full impact.

While spot shortages of vaccines have been reported, people seeking a vaccine should be able to get one, even if they have to check a few locations to find it. And they still should, even though it takes about two weeks for the full protection to kick in.

“Better late than never,” Frieden said.

Researchers have been working on how to better predict when a bad flu season is coming. But the pandemic of 2009-10, when a novel H1N1 virus hit the country, and now this somewhat surprising season “shows we’re not quite there yet,” said Yonatan Grad, research fellow at the Center for Communicable Disease Dynamics at the Harvard University School of Public Health.

The only defense against the flu now is to develop the most effective vaccine and deliver it to as many people as possible, he said.

CDC’s early estimates peg this year’s vaccine at about 60 percent effective — lower than public health officials would like but in line with recent years and expectations. That means people who got the vaccine are 60 percent less likely than others to have to go to the doctor because of the flu.

“The vaccine is not perfect, but it’s the best tool we have,” Frieden said.

The vaccine contains the three most common strains of influenza that are circulating, accounting for about 90 percent of cases, he said. There’s a bit of guesswork about which strains will dominate in any given year; the vaccine has to be ready before flu season. But “the match this season was a good one,” Shaman said.

Right now, the technology allows only three strains of virus in any flu vaccine. But as soon as next year, the flu vaccine will be able to hold four strains, said Joseph Bresee, head of the CDC’s flu division.

The most recent vaccination rates are from mid-November, when an estimated 37 percent of the public — 112 million people — had been immunized after the initial fall public education push. But there are signs that more people are getting the vaccines in the past two weeks, so the number could reach half the population by the end of the season — historically a pretty good level, Frieden said.

The most similar recent flu season was 2003-04, which began even earlier than this one and was caused by a version of the strain that is dominant this year, known as the H3N2 virus.

The 2009-10 pandemic struck even earlier, peaking in October. Although the virus was relatively weak — much weaker than feared at the time — it was widespread, claiming the lives of 279 children, nearly four times the average of the previous five seasons. By contrast, 20 children have died of the flu so far this season.

The flu kills 3,000 to 49,000 people each year, according to the CDC, but the agency monitors related pediatric deaths only on a weekly basis. It tends to be most dangerous for frail, older people, or those with other health problems.