05/25/2005 12:20 pm ET Updated May 25, 2011

Vaccines and Autism: More Answers

As the former director of Los Angles' Immunization Program and a frequent consultant to the WHO on vaccine preventable diseases, I think that the questions raised in David Kirby's posts and the answers given in Dr. Jay Gordon's need another perspective. Clearly, safety issues surrounding vaccines need to be looked at frequently and from every conceivable scientific angle. However, I would like to remind parents what the situation would look like if we did not have the current vaccines to use. It's not a very pleasant picture. To a large degree, without vaccines the health of our children might look similar to children born over 100 years ago -- when each year thousands of infants and young children dying of or debilitated by polio, diphtheria, measles, whooping cough, pneumonia, and other infections.

More recently, having worked in countries where many children have not had the benefit of such immunizations, I have seen first-hand what these diseases can do. For example, in the early 1990’s in China, before successful attempts to eradicate polio, I was witness to one of the largest outbreaks of paralysis in the world -- with over 400 polio cases (all which could have been prevented with polio vaccine). In El Salvador I watched a 7-year-old girl with measles who was hospitalized with pneumonia struggle to breath -- this child had not been vaccinated against measles. There are thousands of other examples of this kind, and even in many places in the world today children are still suffering daily from these diseases! Thus, I feel that it is critically important that parents recognize the ability of the current Measles, Mumps, Rubella (MMR) vaccines to protect infants and children from once common, and potentially serious infectious diseases.

MMR vaccine has been used widely in the United States since 1971 –- and the available epidemiologic evidence does not support a causal link between MMR vaccine and autism. (Also, MMR vaccine has never had the thimerosal additive). Two separate groups, the Institute of Medicine (IOM) of the National Academy of Sciences and the American Academy of Pediatrics (AAP), have reviewed the evidence regarding a potential link between autism and MMR vaccine, found none, and independently concluded that the U.S. should continue its policy of using MMR vaccine.

Analysis in recent reports of increased Autism due to the measles vaccine suffers from what might best be described as the "Ecological Fallacy." That is, mistakenly using broad trends to implicate a specific causal relationship. An example of this type of thinking is -- the birth rate decreases in Belgium during the 1960's were due to the decrease in the stork population. Of course, the two are not causally related -- the decrease in births were principally due to birth control, and the decrease in storks due to changes in the style of the roofs which made it more difficult for storks to nest. An excellent presentation on the difficulties in conducting such trend analysis for autism is given by Dr. Eric Fombonne. Also, to read more about autism and vaccine issues, I recommend going to the CDC site on this subject.

It is currently recommended that all children in the United States be protected against 11 vaccine-preventable diseases. This requires 16 to 20 injections within the first 18 months of life. In addition to protecting children against Measles, Mumps, and Rubella, these vaccines protect children from paralysis due to polio (inactivated poliovirus), painful lesions (varicella/chickenpox), lockjaw (tetanus), pneumonia (pneumococcal conjugate), whooping coughs (pertussis), liver disease (hepatitis), etc. Worldwide, hundreds of millions of children have now been vaccinated and received the benefit of the protection that these vaccines provide -- including my own two children.

Dr. Marc Strassburg is an adjunct Professor of Epidemiology at UCLA, and has served as a consultant to the World Health Organization (WHO) on vaccine preventable diseases for over 34 years