PLoS publishes an online journal of “Neglected Tropical Diseases”. The tropical areas often have lower density populations than temperate zones, and there are fewer scientists to investigate health issues. However, these “neglected” diseases can adversely affect many people. “Pararama associated phalangeal periarthritis” is a disease of rubber plantation workers. The disease is characterized by joint-space narrowing, bone alteration, degeneration of the articular cartilage and immobilization of the affected joints. This disease is caused by contact with the Pararma caterpillar.
Pararama is the common name of the caterpillar, Premolis semirufa., the caterpillar of an Arctiid (Tiger) Moth. The caterpillars have urticating hairs that contain enzymes and other components that cause intense heat, pain, edema and itching which lasts for three to seven days. The caterpillars are found on rubber trees and workers inadvertently brush the caterpillars when tapping the trees. A recent study by a group of Brazilian scientists investigated the components of the urticating hairs. They have partially characterized the components and found that the chemicals in the hair are highly allergenic. The problems that workers suffer in their joints may be due to an inflammatory immune reaction caused by the caterpillar hairs.
Pararama Caterpillar
Photo by Rosana de Fátima Shoji
Living With Insects Blog 