County Epidemiologist Plays Medical Detective With Infectious Diseases

Times Staff Writer

In the confines of his Santa Ana office, Orange County epidemiologist Thomas J. Prendergast pulled off his sweater, loosened his tie and unbuttoned his shirt to reveal a white T-shirt emblazoned with the words “Safe Sex.”

“It’s because of my job,” said Prendergast, explaining the reason his children gave him the shirt. The 48-year-old doctor monitors infectious diseases for the county, including AIDS, which is thought to be transmitted primarily through sexual contact.

“You should see the condom lei we gave him,” said his assistant, Rosann Lowery, referring to a gift in the shape of a Hawaiian floral wreath that he received from co-workers.

Prendergast can use a few moments of levity in an otherwise serious job that many would consider rather grim.


Prendergast said his job basically involves “looking for what makes people sick in large numbers.” So after spending more than 11 years tracking diseases and talking to people about them, one might think that Prendergast would be, well, a little sick of the job.

Not a chance. “It’s still an incredible thrill,” he said, tucking his dress shirt back into his slacks.

“It’s fascinating. It allows you to be inquisitive and insightful. And you get paid for it,” he said.

Since he became the county epidemiologist in 1977, he has seen the number of measles cases diminish to just a handful and the number of AIDS cases grow.


As of November, 861 cases of AIDS had been diagnosed in Orange County since 1980, according to county health officials. Of those, 505 people have died of the disease. An additional 441 people were found to have AIDS-related conditions, and of those, 23 have died.

“AIDS is certainly the largest, most severe epidemic we’ve faced in a long time,” he said.

Prendergast considers AIDS to be the most urgent public health problem and said he believes that his office has a major responsibility to deal with it. So, he spends much of his time fighting what he said may be the biggest challenge aside from treating AIDS patients or seeking a cure--correcting public misconceptions about the disease.

“Most of the fears people have about catching the disease are not necessary,” Prendergast said. “We can never treat the disease openly if we deal with it inappropriately.”


Earlier this year, Prendergast met with school officials, students and parents to ease their fears when 11-year-old Channon Phipps of El Toro, a hemophiliac who has tested positive for exposure to the AIDS virus, returned to school.

“There was no medical or public health reason why he should not be in school. I think it’s important that the anti-discrimination message not just come from the gay community,” said Prendergast, who regularly visits AIDS patients in hospitals.

Aside from dealing with the AIDS epidemic, Prendergast also spends time monitoring the transmission of other communicable diseases, which can include everything from the latest influenza attack to cases of food poisoning and infectious hepatitis.

“On good days, something comes together that makes sense,” he said. “The other days, there are mostly meetings all the time.”


One of the major trends Prendergast has tracked is the transmission of diseases such as hepatitis A and those associated with diarrhea and respiratory ailments among children in day-care centers. The problem has led to better testing of children and their families.

“This type of medicine (epidemiology) is so interesting because things always change,” Prendergast said. “I enjoy working on problems even though they are sometimes devastating.”