08/01/2008 05:12 am ET | Updated Nov 17, 2011

Is Autism an "American Disease?" Somali Immigrants Reportedly Have High Rates

NOTE: Please also see my post today at AGE OF AUTISM -- "Top Researcher: Spread Shots Out 'As Much As Possible' With Mitochondrial Disorders"

A very interesting article was published today by Elizabeth Gorman on that should be researched further: It might shine new light on genetic, and possibly environmental factors in autism.

The article reports that an unusually large proportion of Somali-speaking children in Minnesota have autism, something that has also been noted in Sweden, where Somali immigrants call autism "the Swedish Disease," because they did not see it back in East Africa.

According to the report, almost 6 percent of the Minneapolis school district's total enrollment is made up of Somali-speaking students. But in the city's early childhood and kindergarten programs, "more than 12 percent of the students with autism reported speaking Somali at home," and over "17 percent of students in the district's early childhood special education autism program are Somali speaking," the article said.

Somali kids with autism seem to be doing worse, on average, than their school mates: "About a quarter of all autism children who attend autism classrooms for students functioning too low to be mainstreamed in regular schoolrooms are Somali."

The statewide autism rate in Minnesota is already quite high -- at 100 per 10,000 children, as compared to the national average estimate of 67 per 10,000. In the Somali immigrant community, however, it could be much higher than either of those figures.

Why would that be? There is almost certainly a strong genetic connection at play here, but there may be other factors as well, including a lack of vitamin D from sunlight, (see the Swedish study in article) or, yes, vaccinations.

I do not know if vaccines are playing a role at all here. In fact, this report says that the Somali children were all born and vaccinated in the United States (though it seems to me that some must have immigrated here).

The "American Disease" idea comes from Somali parents themselves, and from some of the experts who work with them.

Anne Harrington, an early childhood special education coordinator for the Minneapolis school district and a specialist on the topic, told Gorman that Somalis "Are given more [vaccines] than we get, and sometimes they're doubled up. Then their children are given immunizations. In Somalia, their generations have not received these immunizations, and then suddenly they're getting just a wallop of them in the moms and then in the babies. That's certainly a concern that's been expressed to me by the Somali population."

I have never heard that before, and there may be nothing to it. On the other hand, the Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices recommends that refugee adults receive at least 10 vaccines -- including pregnant women. Some of them contain thimerosal.

In addition, any of these kids who are older than five -- meaning they were born in 2002 or earlier -- could have received thimerosal in their vaccines.

Whatever the reason for the apparent higher rates of autism (ie, genes, sunlight, vitamins, vaccines, all of the above, none of the above) it is an interesting phenomenon and, it seems to me, an intriguing avenue of research.

There are data out there to suggest that elevated autism rates may not be limited strictly to immigrants from Somalia:

# A study of pervasive developmental disorder (a form of ASD) prevalence in Montreal school districts in 2003-2004 showed that the average PDD rate in the city's five predominantly French-speaking school districts (ie, largely Canadian-born) was 42.3 per 10,000 students, but in the largely English-speaking school district, where many immigrant children live, the rate was 69.2 per 10,000.

# In the English-speaking district, although the overall PDD rate was 69.2 per 10,000, among foreign-born children it was 106.6 per 10,000, and among Canadian-born children it was 67.6 per 10,000 - or 58% higher in the foreign born population.

# In Sweden, researchers reported that the incidence of autism among Somali immigrant children is far higher than among children living in Somalia (though better medical care and diagnostics would play a role, I'd think). Swedish media report that Somalis living in Sweden have dubbed autism, "The Swedish disease," because it is so common among Somali immigrants.

# These data might support reports that autism rates are also higher in immigrant communities in North America. On June 6, 2007, the Canadian Broadcasting News reported that, "autism rates are higher in immigrant families." Health-care specialists in Montreal, it said, were, "trying to understand why such a high number of autistic children come from immigrant families, a phenomenon seen in major cities across North America."

# This information MIGHT also help explain why autism numbers in California (and Minnesota, for that matter), are still high. In California, between 2003 and 2007, the rate of autism among black and white children enrolled in the state's DDS program increased by 50%. But the rate among Asian children in the same period went up by 79%, and the rate among Hispanic kids increased by 84.2%. The growth rate was about 58% higher among Asian and Hispanic children than black and white children.

# One in four California residents are foreign born. The majority are from Mexico, Central America, China, Korea, the Philippines and other countries with high vaccination rates (Mexico's is about 92%) and that still use the full amount of thimerosal in shots. Many if not most of these children are routinely revaccinated upon entry into the United States.

It would be very interesting, I believe, to look at autism rates in high and low immigration states. Not to implicate vaccines, but to find out if children of immigrants are more at risk than our native born population -- and why.