Update at 1:12 p.m. Feb. 7: The number of flu-related deaths in California increased in the week ending Feb. 1 by 55 — a 37 percent jump — to a total of 202 confirmed deaths for the season, according to Dr. Ron Chapman, director of the California Department of Public Health.
Four of those who died were children. The Public Health department said it is investigating an additional 41 deaths to determine if they were flu-related.
While high, the week's death toll was far below the 97 who died between Jan. 18-25, and a senior state health official expressed cautious optimism that California's flu epidemic may be easing.
Preliminary data indicate that the number of new flu cases peaked about three weeks ago, said Dr. James Watt, head of the Communicable Disease Control division in CDPH's Center for Infectious Diseases. He said he is "hopeful that the trend will be downward" in terms of flu-related deaths.
But Watt cautioned that the flu is "notoriously unpredictable," and activity could spike again.
He said about 90 percent of those who died from the flu had underlying medical conditions, such as asthma, diabetes, chronic heart or lung disease, or immunosuppressive disorders.
Previously: The death toll for the entire previous flu season was 106. This season has seen the most fatalities since the pandemic of 2009, during which 539 people died.
Chapman also announced that a Riverside County infant under six months of age has died of pertussis, also known as whooping cough. It is the first confirmed pertussis death in the state since 2010. He did not say whether the child's mother had been vaccinated, but he said the case underscores the importance of pregnant women getting vaccinated, because the immunity they develop is passed to their infants until the babies are old enough to be vaccinated themselves.
Pertussis is cyclical, with peaks in incidence every 3 to 5 years. In 2010, California experienced a pertussis epidemic. There were more than 9,100 cases, including 10 deaths.
The current flu epidemic, which has reached levels not seen since the pandemic of 2009, has put most big area hospitals on the defensive. Officials have implemented a range of precautions to keep patients, visitors, and staff safe.
Cedars-Sinai in Los Angeles was spurred into action when it noticed an increase in emergency room visits and a rise in the number of young people affected by the flu, said hospital epidemiologist Rekha Murthy.
"Those two factors really led us to concerns about transmission of influenza to vulnerable patients," said Murthy.
At Cedars-Sinai everyone is given a mask when they enter and anyone who is sick is discouraged from visiting.
Officials say they are also paying extra attention to high-risk areas in their hospitals, such as neo-natal intensive care units and cancer wings.
Even before the flu epidemic, City of Hope in Duarte had required people visiting admitted patients to wear masks and gloves, said Anne Marie Flood, infection prevention manager at the hospital.
Now, any visitors who are sick are sent home, children under five are not allowed at all and outpatients who show symptoms are required to wear a mask and are separated from others.
"I like to say the only sick people who belong here are our patients," said Flood. "It presents a risk not only to our patients, but to our healthcare workers, other visitors and the like."
Kaiser Permanente says its medical centers have implemented different precautions, depending on how hard they have been hit by the flu.
Some of the chain’s hospitals are going beyond passing out masks and hand sanitizer, said Kalvin Yu, Kaiser’s regional chief of infectious diseases.
Kaiser's Fontana medical center has enacted a policy under which anyone 14 years or younger is prohibited from entering the hospital, said Yu.
Kaiser is telling any of its members who are sick with the flu to not go in to see their doctor, unless they have other medical issues.
In addition to Fontana, Kaiser says its Baldwin Park, West Los Angeles and Orange County medical centers are considered flu hot spots.
At UCLA Health Sciences Center, masks are not mandatory, but every staff member is on the lookout for people who appear to have the flu. Those with symptoms are discouraged from visiting until they are better, said spokeswoman Roxanne Yamaguchi Moster.
UC Irvine Medical Center is requiring anyone who seems to have the flu to wear a mask if they have to be in the hospital, said spokesman John Murray.
Protections are also in place for hospital staff. In October, Los Angeles County Department of Public Health Director Jonathan Fielding mandated that acute care hospital staff get the flu vaccine or wear a mask throughout the flu season.
The flu hospitalization rate is lower than in recent seasons, but the number of deaths is higher, due at least in part to the more severe H1N1 strain that has hit this season.
Hospital officials review flu data on a weekly basis. Kaiser's Yu said the figures appear to be stabilizing, although they are still high. He warned that it's too soon to declare that the virus is waning, since H1N1 peaked twice in 2009 and nearly doubled the length of the flu season.