Ynes Ortega is a key addition to the University of Georgia research team at the Griffin, Ga., Center for Food Safety and Quality Enhancement. Ortega is one of a handful of researchers in the world studying parasites on food.
"We're extremely excited about the new dimension of food safety expertise Dr. Ortega brings to our center," said CFSQE director Michael Doyle. "Her research into this emerging area of foodparasitology is certain to have tremendous impact on understanding the behavior, control and elimination of food-borne parasites."
Either bacteria or parasites usually cause food-borne illnesses. E. coli O157:H7, Salmonella and Camplyobacter are among the bacteria that cause these illnesses.
E. coli's Not the Only Bad Guy
Ortega's research, though, focuses on parasites in food and water. In 1993, she was part of a team of scientists that first identified Cyclospora, a parasite linked to outbreaks in raspberries, basil and lettuce.
The parasite was falsely linked to strawberries in a 1995 Texas outbreak. "The strawberries were blamed," Ortega said, "and strawberry growers lost $20 million in one week."
At the time, no one knew what was causing the illnesses. "The outbreak happened in Texas, but the whole world got involved," she said. "Researchers from universities, the CDC (Centers for Disease Control and Prevention), FDA (Food and Drug Administration) and health officials were all working together."
Though strawberries were being blamed, the team's research didn't support the speculations. "Later, the outbreak was epidemiologically linked to raspberry consumption," Ortega said.
Parasites Need Humans to Survive
Unlike bacteria, parasites need human hosts to survive and multiply. This makes the work of researchers like Ortega much harder.
"We can't multiply Cyclospora in the lab to study them," she said. "We have to take samples from sick people. It's hard to study a parasite you can't reproduce."
On the positive side, parasites seem easier to kill in humans. "Bacterial outbreaks are fast, and they kill fast," Ortega said. "On the other hand, parasites need time to multiply. So the process takes longer."
Medication isn't required to get rid of some parasites. "Our bodies fight them with our immune systems," she said.
Other parasites require medications, which aren't always effective. "Basically, you have to live with two to four weeks of diarrhea if the medication doesn't work," she said.
A Strong Immune System is Your Best Defense
As with food-borne illnesses caused by bacteria, parasite illnesses hit those with low immune systems harder.
"Currently, there is no efficient treatment for Cryptosporidium infections," she said. "And they can be life threatening. The best defense you can have against parasites is a strong immune system."
In her UGA lab, Ortega is studying the biology of these parasites. She's trying to find how to isolate them and detect them on food.
"The water industry has some experience and methods of detecting parasites," she said. "But the food industry doesn't."
By training, Ortega is a medical parasitologist. She is working to adapt detection methods used in the medical field. "We have to find out how to detect them and how to stop them," she said.
(Sharon Omahen is a news editor with the University of Georgia College of Agricultural and Environmental Sciences.)