FRIDAY, May 8, 2009 (HealthDay News) -- The swine flu outbreak in the United States is far from over, with hundreds of new cases being reported each day, federal health officials cautioned on Friday.
"I want to address an issue that's been concerning me, that has to do with a sense of having dodged a bullet, a sense that this is over," Dr. Richard Besser, acting director of the U.S. Centers for Disease Control and Prevention, said during an afternoon teleconference. "While we have seen a lot of encouraging news in terms of severity, we continue to see hundreds and hundreds of new cases each day," he said.
The good news, Besser said, is that most of the infections continue to cause only mild illness, similar to the seasonal flu, and virtually all patients are recovering quickly and fully.
As of Friday, there were approximately 2,500 confirmed and probable cases in 43 states and the District of Columbia, Besser said. "There are 1,639 confirmed cases in 42 states and D.C. We have approximately 850 probable cases reported nationwide," he said.
Fifty-seven people have been hospitalized, he said, adding that, of 26 hospitalized patients, 58 percent had an underlying health condition; seven patients had asthma.
And while the swine flu -- technically known as the H1N1 virus -- is similar to seasonal flu, there are some important differences, Besser said. "One thing we are seeing, unlike seasonal flu, a higher percentage seem to be having vomiting and diarrhea," he said.
Meanwhile, a new Harvard University survey finds that many Americans have taken measures to protect themselves and family members from the disease.
For instance, 67 percent of those surveyed said they or someone in their home are washing their hands or using a hand sanitizer more frequently, and 55 percent said they've taken steps to stay at home if they or a family member gets sick.
"This outbreak has permeated a lot of American life," Robert J. Blendon, a professor of health policy and political analysis at the Harvard School of Public Health/Kennedy School of Government, said during the teleconference. "This is something that has really gotten into their lives. This is not something people are watching but not doing anything about. It's incredible when you see the list of things people are trying to do to avoid the situation."
Among those steps cited by the survey:
- About 25 percent report that they or a household member have avoided air travel or avoided public places where many people gather. About one-third said they personally have taken steps to avoid being near someone who has flu-like symptoms.
- 14 percent said they've stopped shaking hands with people, and 12 percent said they have stopped hugging and kissing close friends or relatives, even though 61 percent aren't concerned that they or someone in their immediate family may get sick from the swine flu in the next 12 months.
- 83 percent said they're satisfied with the way public health officials have managed the response to the outbreak, and 88 percent said they're satisfied with the information health officials have provided.
On Thursday, Besser said most new cases of swine flu in the United States are now caused by person-to-person transmission and not some link to Mexico, as was the case when the outbreak began two weeks ago. Mexico is believed to be the source of the outbreak.
The two U.S. deaths linked to swine flu occurred in individuals with multiple underlying health problems, according to a CDC report released Thursday by the New England Journal of Medicine.
The first victim -- a Mexican toddler named Miguel Tejada Vazquez who had been treated at a Texas hospital -- suffered from a chronic muscle disorder called myasthenia gravis, and also had a heart defect, low oxygen, and problems swallowing.
The second case involved 33-year-old schoolteacher Judy Trunnell, who suffered from asthma and rheumatoid arthritis and who was 35 weeks' pregnant and in a coma when she died in a Texas hospital on Tuesday. Doctors delivered her baby girl via Cesarean section.
On Friday, news reports said Canada had confirmed its first death linked to swine flu, a woman in her 30s living in northern Alberta. That woman also had other medical conditions, a provincial health officer noted.
On Thursday, the New England Journal of Medicine released a study by CDC researchers that said 11 cases of infection with a swine flu virus similar to that involved in the current outbreak have been recorded in the United States since 2005. These viral strains were so-called "triple-reassortant" viruses, meaning that -- like the current H1N1 strain -- they contained genes from bird, pig and human viruses.
The findings suggest that "all human infections with influenza viruses of animal origin, even those that appear to be clinically mild, warrant a thorough public health investigation to assess the epidemiological risk to humans," the researchers said.
Testing has found that the swine flu virus remains susceptible to two common antiviral drugs, Tamiflu and Relenza, according to the CDC.
U.S. health officials earlier this week said the outbreak of swine flu appears similar to the seasonal flu in its severity, so schools across the nation should remain open and any schools that did close should reopen.
On Friday, the World Health Organization was reporting 2,500 confirmed cases of swine flu in 25 countries, with Canada, Spain and the United Kingdom having the most cases outside of Mexico and the United States.
There were 1,204 laboratory-confirmed cases in Mexico, including 44 deaths. The United States had reported 896 confirmed cases, including the two deaths, the WHO said.
Meanwhile in Mexico, the country continued to emerge Friday from a virtual shutdown designed to limit infections. High schools, universities, dance halls, movie theaters and bars have reopened, and primary schools are to reopen next week, the Associated Press reported.
Reports emerged Friday that the swine flu has extended its spread in the Southern hemisphere, where flu season is just beginning. Argentina and Brazil have now confirmed their first cases of swine flu, joining Colombia as South American nations reporting infections, the news service said.
For more on swine flu, visit the U.S. Centers for Disease Control and Prevention.