Does Lyme disease induce autism in children?

The view that Lyme disease induces autism in children has been advanced by the Lyme-Induced Autism Foundation (LIAF) which claims that up to 90% of autistic children are infected with Borrelia (1). There are no published data to substantiate such a claim. Having a positive ELISA or Western Blot test is not proof of active infection; it might indicate the presence of antibodies that are the result of past infection with Borrelia burgdorferi, the causative agent of Lyme disease. Such antibodies may persist at low levels, months to years after the active infection has been cured by appropriate antibiotic therapy. In some persons, a positive ELISA or Western blot is due to a non-specific cross-reaction (i.e., a false positive test).

There are serious problems with the quality of the laboratory tests used to support the claim that a large percentage of autistic children are seropositive for Lyme disease. First, the actual data upon which the claim is based have never been published in a peer reviewed scientific journal; this casts doubts on their accuracy. Second, there has been no independent confirmation to establish that the results are valid and reproducible. Third, in many cases, it appears that non-standard criteria were used to interpret the Western blots that were used to support an association between Lyme disease and autism. Such criteria are at variance with those recommended by the CDC, thereby resulting in a significant number of false positive tests. Consequently, the unpublished results of the serological tests reported by the LIAF must be viewed with grave skepticism.

The results of two recent carefully conducted controlled studies completely refute the erroneous claim of the LIAF, namely, that Lyme disease induces autism in children (2,3).

It should also be noted that data on the prevalence of autism and Lyme disease (number of reported cases per 100,000 residents) for nine States (Al, AR, CO, GA, MD, MO, NC, PA, SC, and WI) for the years 2004 and 2006, provide no indication of an association between Lyme disease and autism (4,5). An analysis by Spearman’s rank correlation test yields r values of 0.234 and 0.317 for the years 2004 and 2006, respectively. In this particular method of statistical analysis, r values must be at or very close to 1.0 to affirm a close association between Lyme disease and autism. Furthermore, the average age at which the first signs/symptoms of autism occur in children is lower than that of Lyme disease, and there is no evidence that autistic children are exposed to ticks at a greater frequency than normal children.

Since families with autistic children already suffer enormous financial and emotional burdens, they should not have their hopes needlessly raised by unproven speculations that are not supported by scientific evidence. It would be irresponsible and even harmful to treat autistic children with extended antibiotic therapy, as some physicians are already recommending and doing, in the absence of indisputable evidence of a persistent infection. Neither the National Institutes of Health nor the Autism Science Foundation, which fund almost all of the research on autism and have developed many promising and successful approaches for treating autism, have any evidence to support a link between Lyme disease and autism.

References:

1. http://www.lymeinducedautism.com/lymeautismconnection.html

2. “Serologic markers of Lyme disease in children with autism”.
Ajamtan, M., Kosofsky, B.E., Wormser, G.P., Rajadhyalsha, A., and Alaedini, A.
JAMA 309: 1771-1772, 2013.

3. “Lack of serum antibodies against Borrelia burgdorferi in children with autism”
Burbelo, P.D., Swedo, S.E., Thurm, A., Bayal, A., Levin, A.E., Marques, A.,
and Iadorola, M.J.
Clinical Vaccine Immunology, May 2013, on-line ahead of print publication.

4. Autism and Developmental Disabilities Monitoring Network Report of 2009(http://www.cdc.gov/ncbddd/autism/states/ADDMCommunityReport2009.pdf).

5. Reported Lyme Disease Cases by State, 1999-2008(http://www.cdc.gov/ncidod/dvbid/lyme/ld_rptdLymeCasesbyState.htm