Peak flu season hits Mountain View

Flu season is in full swing in the Bay Area, leaving four people dead and sending some patients into intensive care. In an effort to curb the spread of the virus, local hospitals are restricting visitors to keep contagious flu-carriers away from patients.

Santa Clara County reached “peak” flu season last week following six flu outbreaks across the county, according to Catherine Nalesnik, infection preventionist at El Camino Hospital. She said the hospital is seeing a fast-increasing number of people in the emergency room who are testing positive for the virus.

Of the patients coming in with the flu, about eight to 10 people a week must be hospitalized, which Nalesnik called “very unusual.”

The temporary visiting restrictions imposed by El Camino Hospital last week are intended to slow down the uptick in flu cases by discouraging people with flu-like symptoms from visiting patients in the hospital. The restrictions are expected to continue through the end of the flu season.

“Because of the upsurge of flu and what we’re seeing in the emergency department, the goal is to limit any transmission of flu,” Nalesnik said.

All children under the age of 16 are barred from visiting patients. Nalesnik said the restrictions focus on kids because they are contagious for several days longer than adults. In children, the flu has a longer incubation period, making it easier to accidentally spread the virus.

“They could be exposed to the flu and spread it without really knowing it,” she said.

Children are also more likely to catch the flu because their immune systems are still developing, and they are more susceptible to flu-related complications and respiratory infections, according to the U.S. Department of Health and Human Services.

El Camino Hospital sent out notices to let people know about the visitor restrictions and instructed all the practitioners to inform patients. So far, people have been willing to follow the restrictions, Nalesnik said.

“People in our community realize it’s widespread throughout California, and they’re very accommodating,” she said.

Other hospitals with visitor restrictions include Good Samaritan Hospital and O’Connor Hospital, both in San Jose. El Camino Hospital had visitor restrictions during the swine flu outbreak in 2009, as well as last year during the surge in flu cases last year. Nalesnik said there are more cases this year than last year, putting a strain on the emergency department and other hospital facilities.

Ineffective vaccines

The flu season is particularly nasty this year, in part because the flu vaccine was not as effective in preventing the spread of the virus. Each year, the U.S. Food and Drug Administration determines which viruses to target in vaccines used across the country. The three strains chosen this year were H1N1, H3N2 and B viruses.

The problem is that the genetic makeup of viruses change over time, and the H3N2 strain experienced a genetic “drift” that rendered the vaccine less effective. H3N2 happens to be the most prevalent strain this flu season, and two-thirds of H3N2 cases are the genetically drifted strain.

According to a Jan. 16 report by the Center for Disease Control, the vaccine has only been 23 percent effective this year.

“What that translates into is more hospitalizations and more deaths,” Nalesnik said.

On a good year, Nalesnik said the vaccine is anywhere from 60 to 70 percent effective. She said disease experts have been pretty lucky making predictions on which strains will be the most prevalent from year to year, but not this year.

The Center for Disease Control is still recommending that people get vaccinated, as it may still provide some protection against the flu this season, particularly against the other strains that are well-matched by the vaccine. People under the age of 5 and over the age of 65, as well as people with chronic medical conditions, are considered “high priority” groups for vaccination, according to the Santa Clara County Public Health Department.

El Camino Hospital is also encouraging people to practice simple influenza-prevention tactics like washing their hands, coughing and sneezing into their sleeves, and staying home when ill.