TUESDAY, Jan. 9, 2018 (HealthDay News) -- Americans are being hit with one of the worst flu seasons in years, with misery now widespread across 46 states, health officials say.
In the West, emergency rooms in California and Arizona are packed with people struck by the flu, and drugs that ease the illness are in short supply as doctors struggle with a sharp spike in cases.
Further complicating matters, many hospitals nationwide are struggling with a shortage of intravenous bags that contain fluids that deliver medicine to treat dehydrated patients, including flu patients. The reason: many of the bags are produced by factories in Puerto Rico, which is still dealing with power problems caused by Hurricane Maria in mid-November.
Meanwhile, flu cases are also widespread across the Northeast, and in Florida health workers are reporting a January surge in severe cases.
Virtually no region of the country has been spared, as an imperfect vaccine and a long bout of cold, wintry weather are conspiring to turn this flu season into a severe one.
The South, Midwest, Southwest and West have been particularly hard hit, according to the U.S. Centers for Disease Control and Prevention.
"This is not unexpected," said Lynnette Brammer, an epidemiologist in the CDC's influenza division. "Over the holidays, flu activity increased a good bit. On a national level, the drugs are still there, but in areas hard hit by flu the local pharmacy may not have them."
To make matters worse, the flu vaccine is not a good match with the H3N2 flu strain that is dominating the season so far, she said. At this point, 80 percent of reported flu cases are this more severe strain, according to the CDC.
Dr. Daniel Jernigan, director of the CDC's influenza division, told The New York Times, "H3N2 is a bad virus. We hate H3N2."
H3N2 also tends to be very bad news for the very young and the very old.
Dr. Matthew Mullarky, an emergency room doctor at St. Joseph Hospital in Orange, Calif., told the Los Angeles Times that half of the patients he saw on a recent shift were so sick they had to be admitted to the hospital. Most were older than 85, and struggling with both the flu and pneumonia.
"It's incredibly scary," Mullarky added.
The CDC doesn't keep track of how many adults die from flu, but it can be as many as 60,000 in a bad season. The agency does track child deaths. So far, 13 U.S. kids have died from flu, Brammer said.
This year's vaccine contains the same mix as last year's shot. That vaccine was 43 percent effective against the H3N2 virus and 48 percent effective overall, according to the CDC.
The vaccine may be less effective against H3N2 strains because it's manufactured in chicken eggs, which some recent research has shown interact with H3 strains, making them less like the circulating strain and therefore less effective.
It's too early to judge the effectiveness of this season's vaccine, but Brammer said she expects it to be about the same as last year.
A recent report about the vaccine in Australia found it was only 10 percent effective against the H3N2 flu strain in that country. But Brammer thinks that estimate is much too low.
Even though vaccine may not be well matched, it doesn't mean you shouldn't get a flu shot, Brammer said. It's still the best protection against H3N2 flu and other flu strains, such as H1N1 and B viruses, which are also circulating, she said.
Brammer hopes that the flu has peaked in the areas where it has been most severe. The South has been suffering with flu for several weeks, and it may have peaked there, she said.
"It should start to decline in the next week or so," she said. But people in places where flu has been less active should brace themselves for the coming onslaught.
Consider what is unfolding in New York state.
"We are seeing a significant increase in cases of flu, and people being admitted to the hospital with flu," said Dr. Bettina Fries, chief of Stony Brook Medicine's division of infectious diseases, in Stony Brook.
The majority of patients being admitted to the hospital for flu are either very young or older than 65, she noted.
"We are also concerned if a patient's immune system is not healthy," Fries explained. "Nowadays, a lot of patients get treated for diseases like rheumatoid arthritis or lupus or cancer treatments, which makes them at higher risk for complications from flu. It's been shown in these patients that vaccination, even if it doesn't prevent them from getting the flu, they will have a milder case and that's highly beneficial."
The unusually cold winter may be adding to the spread of flu, Fries said.
"The cold adds to compromising your immune defenses," she explained. "If you don't have good immunity in the community, then you are going to have higher levels of flu. You are going to see more spread and more disease, and that's what's happening."
It's hard to tell, Brammer said, when this year's flu season will peak. Flu can hang around through winter into spring, she noted.
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