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All 50 States Have Cases of the Swine Flu Virus

How effective is the flu vaccine?

Vaccine effectiveness varies from year to year, depending upon the degree of similarity between the influenza virus strains included in the vaccine and the strain or strains that circulate during the influenza season.

Vaccine strains must be chosen 9 to 10 months before the influenza season begins, and sometimes mutations occur in the circulating strains of viruses between the time vaccine strains are chosen and the next influenza season. These mutations sometimes reduce the ability of the vaccine-induced antibody to inhibit the newly mutated virus, thereby reducing vaccine effectiveness.

Vaccine effectiveness also varies from one person to another, depending on factors such as age and overall health.

The most serious side effect that can occur after influenza vaccination is an allergic reaction in people who have a severe allergy to eggs. For this reason, people who have an allergy to eggs should not receive the influenza vaccine.

The National Center for Infectious Diseases (a division of the Centers for Disease Control and Prevention, CDC) says that influenza vaccine causes no side effects in most people who are not allergic to eggs.

Less than one-third of people who receive the vaccine experience some soreness at the vaccination site, and about 5 to 10 percent experience mild side effects, such as headache or low-grade fever for about a day after receiving the vaccination.

Because these mild side effects mimic some influenza symptoms, some people believe the influenza vaccine causes them to get influenza. However, according to the CDC, "influenza vaccine produced in the United States has never been capable of causing influenza because the only type of influenza vaccine that has been licensed in the United States to the present time is made from killed influenza viruses, which cannot cause infection."

The flu causes complications that may develop into a more serious disease or become dangerous to some groups, such as elderly people and those with chronic medical conditions.

The CDC recommends getting the flu shot every year, between September and mid-November, before the flu season hits (usually December to April). The flu shot takes one to two weeks to become effective.

Although there are many new medications designed to treat flu symptoms and even shorten the duration of the illness, the flu vaccine still offers the best protection against the flu.

Always consult your physician for more information.

US health officials reported swine flu cases in all 50 states, with the total number of people infected probably surpassing 200,000.

"It's accurate to say that there are probably several hundred thousand people that have been impacted by this flu," says Tom Skinner, a spokesman for the US Centers for Disease Control and Prevention (CDC). "But that's in line with what we would see with seasonal influenza if we had the number of cases we are reporting right now."

While the swine flu outbreak continues to decline, new cases will continue to appear, Skinner adds.

A total of 10,053 cases in all 50 states and the District of Columbia, including 17 deaths, were reported on Monday by the CDC. According to the agency, confirmed cases of H1N1 swine flu represent about one in 20 of actual cases, bringing the total number of cases to about 200,000.

Effects of the Swine Flu (H1N1)

According to US officials, infections with H1N1 swine flu virus continue to be mild and recovery is fairly quick, similar to infections with seasonal flu. Based on tests conducted by theCDC, results show that the virus remains susceptible to two common antiviral drugs, Tamiflu and Relenza.

"What was unusual was that in late March into April and late May we saw activity at a higher-than-expected level," says Skinner.  The swine flu outbreak activity increased late in the typical flu season, which is different from other outbreaks.

Last week, Dr. Anne Schuchat, the CDC's interim deputy director for science and public health program, reported that the newly identified H1N1 swine flu virus continues to act like the seasonal H1N1 viruses, which may partly explain why this flu strain affects more younger people.

"Seasonal H1N1 often causes more disease in younger people, compared with the other strains that can be more common in older people," says Dr. Schuchat.

Due to exposure to another H1N1 flu strain that circulated prior to 1957, some older adults may have partial immunity to the H1N1 swine flu virus.

Vaccines for the Swine Flu

According to Dr. Schuchat, if research and testing remain on schedule this summer, a vaccine for the swine flu virus could be ready in October. Viruses from candidates infected with the swine flu virus have been shipped to vaccine manufacturers, she adds.

Dr. Schuchat says, it is still unclear whether a swine flu vaccine is needed. Decisions to move forward would be based on several factors, including the severity and spread of the virus and whether the vaccine will be safe and effective, she reports.

The flu season is decreasing in the Northern Hemisphere but is just beginning in the Southern Hemisphere. Dr. Schuchat states that during the next few months, scientists will be evaluating the virus to see if it mutates or becomes resistant to antiviral medications, or if it is more easily spread among people.

There is no way to tell now if the H1N1 swine flu virus will be more poisonous when - and if - it returns to the Northern Hemisphere with the approach of winter, according to Dr. Schuchat.

On Tuesday, the World Health Organization (WHO) reported that 62 countries have reported 17,410 cases of H1N1 swine flu, including 115 deaths, most of them in Mexico, where the outbreak began.

Always consult your physician for more information.

 

  
 
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