Thursday, January 20, 2011

Lyme Disease Outbreak of 1975

In November of 1975, the Connecticut State Health Department received a call from two mothers who each reported that their child had been diagnosed with juvenile rheumatoid arthritis. Both mothers knew of other children with similar diagnoses in the area of Connecticut they inhabited; Lyme, Connecticut.

The reason that these reports of the disease alarmed officials was because juvenile rheumatoid arthritis was not only very severe, but was also extremely rare in children. And many children had been diagnosed with the disease.

So, officials at the Health Department contacted Dr. Allen Steere, a rheumatologist at Yale University who was fascinated by the case. Steere’s task force helped identify 39 children and 12 adults suffering from rheumatoid arthritis; uncharacteristically high numbers considering that the disease usually affects 1 child out of 100,000.

Steere also discovered several other interesting aspects of the outbreak:

· Most of the cases appeared during the summer, suggesting either a summer virus or an infection carried by an insect or tick vector.

· Unlike other summer diseases this one did not seem contagious.

· 25% of the victims reported having a spreading skin rash before experiencing other symptoms.

· The outbreak was limited to 3 Connecticut towns: Lyme, Old Lyme, and East Haddam.

· Most of the victims inhabited heavily wooded, rural areas; not in the urban setting.

After considering all of these factors, Steere concluded that the disease had yet to be recognized by the medical world and that it was also transmitted by an arthropod (insects). Thus, he named the disease “Lyme Arthritis” (changed to Lyme disease when it was discovered that the joints were not the only parts of the body affected by the infection).

However, Steere was not the first in the world to discover the disease. In 1909, Swedish dermatologist Arvid Afzelius described, in his work, an expanding, ring-like lesion in those bitten by the Ixodes tick. He named the rash “erythema chronicum migrans,” which is Latin for “chronic red rash that increases in size,” or “ECM” for short.

For additional facts about life of Ixodes tick vectors click here.

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