Wednesday, August 24, 2011

A Back to School Basic



The phrase “Back to school,” can elicit a wide range of thoughts. Emotional responses include excitement, nerves, and in the case of my wife a profound “Thank Goodness!” My daughter, about to enter first grade, has a somewhat different opinion. “Can my American Girl go instead?”. No matter what, this is the time of year of making back to school plans and lists. Pencils, erasers, coloring books and computer accessories. Notebooks, crayons, backpacks and brown bag lunches. Scissors, sanitizer and glue sticks. Gym clothes, clean underwear and shoes that fit. Feel like something important is missing? Well if you are a 7th-12th grader without an up to date pertussis (whooping cought) booster, than yes, something important is missing. In fact, this something is critically important – as you may not be allowed to attend school without it.
Last year, the state legislature passed AB354, which mandates an up to date pertussis booster (as part of the Tdap immunization) for all 7th-12th students. Based on this new law and immunization records, an estimated 5,000 students in Marin will need to move the Tdap shot to the top of their back to school list, or else there may just not be a school to go back to. Now, if you or your children are in this group, this requirement likely seems like a hassle, and it is. But, there is a good reason. I’ll take a moment to explain...

Vaccination efforts during the past century have made certain childhood diseases so rare that they seem like remnants of an uncivilized past. Few of us have actually seen a new case of polio or measles, so it’s easy to be lulled into thinking that these ailments are so antiquated they couldn’t possibly cause trouble again. Unfortunately, this is just not true. The diseases that we vaccinate against are not extinct; they are lurking, waiting for enough people to drop their guard. If you think that I am an alarmist, consider these recent outbreaks: polio in Nigeria, measles across the U.S. and whooping cough in Marin County.

We are currently in the midst largest pertussis outbreak in 40 years – with ten deaths in California alone. Nationwide, measles is back – with a confirmed 156 cases in the first half of this year – the most since 1996. These outbreaks should remind us that we aren’t as safe from vaccine preventable diseases as we may think. Pertussis, for instance, is a highly contagious lung infection that can affect both children and adults and classically causes a “whoop” after coughing. In the days before DTP (diptheria-tetanus-pertussis) immunization, pertussis killed thousands of infants every year – often because the cough was so severe that it caused them to start bleeding in the brain. Thankfully, with the advent of widespread vaccination, the number of infections declined 99% between the 1930s and the 1980s and the death rate plummeted to single digits by the 1990s. In the last ten years, however, we’ve seen a resurgence of this infant-killer. Nationwide in 2005, there were over 25,000 cases of pertussis reported to the CDC; 21 of these were in Marin County. There are several explanations for pertussis’ comeback, but mostly it can be blamed on under-immunization. The protection afforded by the pertussis vaccine tends to wear off three to five years after vaccination, thus even children who have received the recommended DTaP series (five shots between the ages of 2 months and 6 years) are at risk for contracting the disease later.  Because of herd immunity (immunity that occurs when the vaccination of part of the community – or herd – provides protection to unvaccinated individuals) many parents think that their children are protected against pertussis (and other diseases) even if they are not fully vaccinated. Unfortunately, the more parents who believe this and exercise the (personal belief) exemption to mandatory vaccination, the more likely it is that herd immunity will fail. This is why a group of pediatricians in Philadelphia have published a manifesto to those who “absolutely” refuse to immunize: “by not vaccinating your child you are taking selfish advantage of thousands of others who do vaccinate their children ... We feel such an attitude to be self-centered and unacceptable.” These pediatricians would be appalled with vaccination rates in Marin – according to the California Department of Public Health, the Marin County kindergarten immunization rate is 84.7%, significantly below the state rate of 92.1%. And while we have long suspected that un-immunized children are at greater risk of disease, we now have solid evidence of this. Two papers published in 2009 by a team of researchers from Colorado document significantly increased risk of pertussis (twenty-three fold risk) and varicella (nine-fold) in children whose parents refuse these immunizations.

So, what can we do to ward off a further surge in preventable infectious disease? Well, a great place to start is at the top of that back to school list. Fortunately, efforts are in play to make this as hassle free as possible. The Marin County Department of Health and Human Services is partnering with the Marin County Office of Education, San Rafael Kaiser Permanente, the Marin County School Nurses’ Association and the Marin Medical Reserve Corps to offer five vaccine clinics in school sites around the county just before the start of classes. At these clinics the vaccine will be offered at no cost to Kaiser members and the many students who qualify for free vaccine under federal rules and at a maximum will cost $32. Dates are August 15th, 16th, 17th, 19th and 22nd. For more information and details visit http://www.co.marin.ca.us/tdap.