NY Times: Ayub Abdi is a cute 5-year-old with a smile that might be called shy if not for the empty look in his eyes. He does not speak. When he was 2, he could say "Dad," "Mom," "give me" and "need water," but he has lost all that.

He does scream and spit, and he moans a loud "Unnnnh! Unnnnh!" when he is unhappy. At night he pounds the walls for hours, which led to his family's eviction from their last apartment.

As he is strapped into his seat in the bus that takes him to special education class, it is hard not to notice that there is only one other child inside, and he too is a son of Somali immigrants.

"I know 10 guys whose kids have autism," said Ayub's father, Abdirisak Jama, a 39-year-old security guard. "They are all looking for help."

Autism is terrifying the community of Somali immigrants in Minneapolis, and some pediatricians and educators have joined parents in raising the alarm. But public health experts say it is hard to tell whether the apparent surge of cases is an actual outbreak, with a cause that can be addressed, or just a statistical fluke.

In an effort to find out, the Minnesota Department of Health is conducting an epidemiological survey in consultation with the federal Centers for Disease Control and Prevention. This kind of conundrum, experts say, arises whenever there is a cluster of noncontagious illnesses.

While there is little research on autism clusters, reports of cancer clusters are so common that health agencies across the country respond to more than 1,000 inquiries about suspected ones each year. A vast majority prove unfounded, and even when one is confirmed, the cause is seldom ascertained, as it was for Kaposi's sarcoma among gay men and mesothelioma among asbestos workers.

It is "extraordinarily difficult" to separate chance clusters from those in which everyone was exposed to the same carcinogen, said Dr. Michael J. Thun, the American Cancer Society's vice president for epidemiology.

Since the cause of autism is unknown, the authorities in Minnesota say it is hard to know even what to investigate.

"There are obviously some real concerns here, but we don't want to make a cursory judgment," said Buddy Ferguson, a health department spokesman. Even counting autism cases is difficult because the diagnoses are first made by the schools, not doctors, and population estimates for Somalis vary widely. Results are expected late this month.

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