The flu strain spreading around this year is mainly Influenza A type H3N2, but it is slightly different from the H3N2 in this year's influenza vaccine.  This means that the flu shot (or mist) is only 23 percent effective in preventing the flu compared to 40 percent in the past.  However, it makes those that catch the flu less likely to stay ill for a long time and thus, less likely to pass it on.

More importantly, only about 42 percent of children have gotten their flu immunization this season.  Immunizations work by the "herd effect." If 90 percent of children got their seasonal flu preventive shot this year, almost no one would get the flu because there would not be unimmunized people to pass it on.  (Normally, about 65 percent of people immunized will completely stop a flu epidemic, but you need much higher coverage. with a relatively ineffective vaccine this year. It has to do with the fact that only about half of the the people directly exposed to flu unimmunized will catch it.)

This season, 56 children in the United States have died of influenza. Children's hospitals and regular hospitals are so full that they sometimes can't take any more patients. Some are pushing out the admitted patients (maybe a little too soon) to open those beds up.

My office tries to get everyone who comes in to get the flu immunization, but many parents are sure that the flu shot gives them the flu. This is simply not true, although it can make them achy for a few days. They won't get the shot and refuse to let their children get vaccinated as well.  In one case, I had one family of five where every single one of them got very ill with the flu. I still think they will not get the shot next year because the mother is sure the shot is dangerous, which it is not.

Make sure everyone has the influenza vaccine if anyone in your family has chronic lung disease (asthma is the most common in children) or heart disease.  And if you know anyone with a chronic disease, you are also protecting them by getting the vaccine.

This brings me to another infectious disease that appears to be spreading throughout the country. Measles were eliminated from the U.S. a few years go, but a doctor lied after being paid to lie by a lawyer to win a case in Great Britain and published a paper that measles cause autism.  It does not.  But the internet never lets anything die and this has led to the growing anti-vaccine movement.

I was always taught to do unto others as you would want them to do unto you.  When you get a measles shot, you protect yourself and everyone you meet.  One measles case in December of a foreign visitor to Disneyland has resulted in the majority of the more than 100 cases of measles in the U.S. in the past six weeks. About 15 percent of cases have resulted in hospitalizations, according to the Centers for Disease Control and Prevention. Most tragically, an infected child could die or have brain damage during the current outbreak or develop permanent brain damage in a few months to a few years.

Now it appears that the measles may have spread to Pennsylvania. Last week, the state Department of Health sent out a health advisory of a possible measles exposure by a Cumberland County resident. The notice lists three places this person was in Cumberland and Franklin counties during the end of January.

Help your community. Get your immunizations and immunize your children.  Many pediatricians will simply not see unimmunized children because we see chronically ill children. A chronically ill child is very likely get the measles or another illness if exposed to an infected child whose parents were too selfish to protect themselves and others.  These chronically ill children could die from an exposure at the doctor's office.

Our neurologist (a doctor who specializes in diseases of the brain and nervous system) and who takes care of the children with measles induced brain damage, wants us to not see unimmunized or partially immunized children.  We have rejected that view so far (as has the American Academy of Pediatrics), but I do wonder if our neurology colleague is right and we are wrong?

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