Swine flu H1N1 outbreak
April 26, 2009
Update: Vitamin D for Flu Protection
Mexican authorities continued to take dramatic steps over the weekend to try to contain the swine flu outbreak that officials say has killed as many as 81 people, and sickened more than 1,300 others.
In the US, two new cases were reported Saturday by health officials in Kansas, as well as a new case in California, bringing the national total to 11, according to the Associated Press. Eight more cases of “probable” swine flu involving school students have been identified by New York City health officials. Cases in the US have so far remained mild.
Dr. Anne Schuchat, the U.S Centers for Disease Control and Prevention’s Interim Deputy Director for Science and Public Health Program, told reporters on Saturday that her agency was “worried, and because we are worried we are acting aggressively on a number of fronts” to investigate the outbreak. She added that, because of the wide geographic spread of the virus so far, the outbreak is already “beyond containment.”
But Schuchat added that U.S. health officials had numerous tools to fight the illness’ spread and protect the health of Americans.
Earlier in the day, the head of the World Health Organization said that the outbreak has the potential to develop into a pandemic.
WHO Director-General Margaret Chan said the outbreak involves “an animal strain of the H1N1 virus, and it has pandemic potential.” But, she added, it was too early to say whether a pandemic would occur, the Associated Press reported.
Twenty-four suspected new cases of swine flu were reported Saturday in Mexico City alone. The government ordered schools closed and all public events have been suspended for the time being, including more than 500 concerts and other gatherings in the city of 20 million residents, the AP said.
All of the original eight patients in the US — six from California and two from Texas — have recovered from their infections. According to the AP, Kansas health officials say that the two new cases there, involving a married couple, were also mild. The newly identified case in California involves a 35-year-old woman who was hospitalized but has recovered.
Speaking to reporters in a Saturday afternoon teleconference, the CDC’s Schuchat said that “at present there are still eight confirmed human cases of swine influenza in the United States. There is a serious situation in Mexico with severe disease and a number of confirmed swine influenza infections, generally among adults.” She stressed that “these are very dynamic times and many things will be changing,” and the spread and severity of the virus would be “very hard to predict.”
While agents at the Border Infectious Disease Surveillance system at the US-Mexico border are on high alert for those who might be carrying the flu, containing the virus was probably out of the question, Schuchat said. “If we found only a new influenza virus in one place, in a small community, we might be able to quench or contain it. But with infections in many different communities as we’re seeing, we don’t think that containment is feasible,” she said. She added that as investigators probe deeper into cases in cities away from California and Texas, new cases are likely to emerge.
But Schuchat stressed that there are other ways to fight the flu. “Containment would be fantastic, but we think that there are many, many tools in our toolbox to reduce the illness and suffering that this virus is causing, and reduce transmission — even if we are not in a circumstance where we could contain it,” she said.
CDC officials said Friday that tests showed some of the Mexico victims died from the same new strain of swine flu that sickened the eight people in Texas and California. It’s a worrisome new strain that combines genetic material from pigs, birds and humans.
“The United States government is working with the World Health Organization and other international partners to assure early detection and warning and to respond as rapidly as possible to this threat,” Dr. Richard Besser, acting director of the CDC, said during a Friday afternoon press briefing.
Besser said the CDC issued an outbreak notice for travelers to central Mexico and Mexico City, alerting people to the flu outbreak. “At this time there are no recommendations for U.S. travelers to change, restrict or alter their travel plans to Texas, California or Mexico,” he said.
While Mexico’s flu season is usually over by now, health officials noticed a sizeable uptick in flu cases in recent weeks. The World Health Organization reported about 800 cases of flu-like symptoms in Mexico in recent weeks, most of them among healthy young adults, with 57 deaths in Mexico City and three in central Mexico, The New York Times reported Friday.
That could be worrisome. Seasonal flus usually strike hardest at infants and the elderly, but pandemic flus — such as the 1918-19 Spanish flu, which killed an estimated 20 million to 40 million people worldwide — often strike young, healthy people, the newspaper reported.
Schuchat said Thursday that the virus in the United States is influenza A H1N1 mixed with swine influenza viruses. The virus contains genetic pieces from four different flu viruses — North American swine influenza, North American avian influenza, human influenza viruses and swine influenza viruses found in Asia and Europe, she said.
“That particular genetic combination of swine influenza viruses has not been recognized before in the U.S. or elsewhere,” Schuchat said.
The viruses found in the United States are resistant to two antiviral medications — amantadine and rimantadine — but are susceptible to the antivirals oseltamivir (Tamiflu) and zanamivir (Relenza), Schuchat said.
Swine flu is a respiratory disease of pigs caused by type A influenza. Swine flu does not normally infect humans. However, human infections do occur, usually after exposure to pigs. Symptoms resemble those of the regular flu, including sore throat, coughing and fever.
Dr. Marc Siegel, associate professor of medicine at New York University School of Medicine, said the current outbreak was unlikely to become a pandemic. “Swine flu could cause the next pandemic, but it is not likely that this thing is going to erupt and take over the world,” he said. Even though the virus is being transmitted human-to-human, “that’s a far cry from becoming a pandemic,” he added.
Dr. Martin J. Blaser, chairman of the Department of Medicine at New York University Langone Medical Center in New York City, also believes it’s unlikely the outbreak will trigger a pandemic.
“The CDC has been doing more surveillance for flu,” Blaser said. “So it could be that these cases have been happening all the time, but we just never saw them. Or it is possible that it is a new strain of influenza that is emerging or it’s a dangerous new combination. That’s why we have to watch it closely.”
From December 2005 through February 2009, a total of 12 human infections with swine influenza were reported from 10 states in the United States. Since March 2009, a number of confirmed human cases of a novel, new strain of swine influenza A (H1N1) virus infection in California, Texas, and Mexico have been identified.
Flu viruses are named after the two main proteins on their surfaces, abbreviated H and N. They are also differentiated by what animal they usually infect. The H in the new virus comes from pigs, but some of its other genes come from bird and human flu viruses, a mixture that the US Centers for Disease Control and Prevention calls “very unusual”.
What can I do to protect myself from getting sick?
There is no vaccine available right now to protect against swine flu. There are everyday actions that can help prevent the spread of germs that cause respiratory illnesses like influenza. Take these everyday steps to protect your health:
- Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.
- Wash your hands often with soap and water, especially after you cough or sneeze. Alcohol-based hand cleaners are
- Try to avoid close contact with sick people.
- If you get sick with influenza, CDC recommends that you stay home from work or school and limit contact with others to keep from infecting them. Avoid touching your eyes, nose or mouth. Germs spread this way.
What should I do if I get sick?
If you live in San Diego County or Imperial County California or Guadalupe County, Texas and become ill with influenza-like symptoms, including fever, body aches, runny nose, sore throat, nausea, or vomiting or diarrhea, you may want to contact their health care provider, particularly if you are worried about your symptoms. Your health care provider will determine whether influenza testing or treatment is needed.
If you are sick, you should stay home and avoid contact with other people as much as possible to keep from spreading your illness to others.
If you become ill and experience any of the following warning signs, seek emergency medical care.
In children emergency warning signs that need urgent medical attention include:
- Fast breathing or trouble breathing
- Bluish skin color
- Not drinking enough fluids
- Not waking up or not interacting
- Being so irritable that the child does not want to be held
- Flu-like symptoms improve but then return with fever and worse cough
- Fever with a rash
In adults, emergency warning signs that need urgent medical attention include:
- Difficulty breathing or shortness of breath
- Pain or pressure in the chest or abdomen
- Sudden dizziness
- Severe or persistent vomiting
Can I get swine influenza from eating or preparing pork?
No. Swine influenza viruses are not spread by food. You cannot get swine influenza from eating pork or pork products. Eating properly handled and cooked pork products is safe.