TUESDAY, Nov. 20, 2007 (HealthDay News) -- Workers helping to rebuild New Orleans after hurricanes Katrina and Rita suffered from several different skin disorders, and new research suggests that many of the rashes were caused by some kind of insect bite.
"Dermatologic conditions have always been really common, but a systematic investigation had not really been done in the past," said study author Rebecca Noe, a staff epidemiologist with the National Center for Preparedness, Detection and Control of Infectious Disease at the U.S. Centers for Disease Control and Prevention in Atlanta. "When I did a literature search, I typically saw people saying 'rashes.' It was really general."
The study was published in the November issue of the Archives of Dermatology.
After the devastation of Katrina and Rita in August and September 2005, scientists had a chance to delve deeper.
Twenty-two percent of diseases treated in the aftermath of the twin disasters were skin-related.
At the end of September 2005, members of the CDC were asked by New Orleans hospital officials to assist investigating an outbreak of skin diseases among construction workers.
A group of men repairing roofs on a military base had rashes so severe they couldn't continue working.
The CDC investigators looked at biopsies and examined the living situations of 136 workers who were staying in 11 screened-in wooden huts on the military base. The workers had limited sanitation facilities (the main shower trailer was out of order).
Fifty-eight of the workers, or 42.6 percent, reported rashes. Of these, 70.7 percent were examined, and 27 (65.9 percent) were found to have papular urticaria, basically a reaction to insect bites.
Eight (19.5 percent) had bacterial folliculitis, an infection causing inflammation around the hair follicles. Six (14.6 percent) were found to have fiberglass dermatitis, irritation and inflammation resulting from contact with fiberglass. Two (4.9 percent) had brachioradial photodermatitis, a reaction to sunlight.
Men who were sleeping in previously flooded huts were 20 times more likely to have developed papular urticaria and four times more likely to have a self-reported rash.
Native American workers were more likely to develop papular urticaria and fiberglass dermatitis.
The investigators never found the creature(s) responsible for the outbreaks, but they suspect that a mite infestation of the huts was responsible.
"Some sort of bug was in the hut," Noe said.
Whenever flooding or another disturbance to the ecosystem occurs, rodents and birds are displaced and mites are left looking for other hosts -- humans included.
The findings were consistent with what on-the-scene specialists saw. Dr. Richard A. Keller, a Mohs' surgeon at Ochsner Health System, returned to work the Saturday after Hurricane Katrina and was the only, or one of the only, dermatologists in the city for two or three weeks.
He saw several cases of skin infections that rumors circulating at the time attributed to some strange, Louisiana-specific disease. Instead, the problems were similar to what the CDC found: papular eruptions, poison ivy and photoallergic eruptions.
"We reassured everyone that this wasn't some odd disease," Keller said. "The big thing we did was dispel the rumors."
The CDC recommended that the men living on the military base be relocated to other sleeping quarters, get improved laundry and shower services, and use insect repellant.
"Lay people need to make sure, if they're going into their home that has been flooded, to wear repellant and, if you can, long-sleeved clothing," Noe added.
More information
The U.S. Centers for Disease Control and Prevention has health information related to hurricanes.
