Strep throat bacteria vaccine developed by U researchers

Mickie Barg

Strep throat, toxic shock and flesh-eating disease are only a few of the ailments caused by Group A streptococcus bacteria. Each year, strep throat alone accounts for 10 percent to 30 percent of general medicine office calls, with millions of people getting sore throats checked and receiving antibiotic prescriptions.
A patented vaccine developed at the University could end this ordeal.
University researchers and Pennsylvania-based Wyeth-Ayerst laboratories, a division of American Home Products, are focusing on a protein on the strep bacteria which suppresses the immune response needed to combat disease. The protein is common in several different diseases.
Normally, when a bacteria invades the body a signal is sent for disease-fighting cells to surround, engulf and digest the microorganism.
“In simple terms, when strep bacteria in the throat starts a fire (the disease-fighting cells) dampen the fire,” said University microbiologist Patrick Cleary, developer of the vaccine.
This particular protein prevents the signal from being sent, allowing the bacteria to invade the mucus-lined surfaces of the body, including the throat and nose, resulting in illness. A course of antibiotics controls the bacteria.
In cases of invasive Group A streptococcus, the bacteria invades parts of the body where it is not usually found such as the blood and lung muscles. The results could lead to severe diseases like toxic shock and flesh-eating bacteria.
Cleary said outbreaks of flesh-eating bacteria a decade ago caused an interest in vaccine development. Grants of nearly $300,000 from the National Institutes of Health and American Home Products ensure continued research.
Center for Disease Control 1998 statistics show about 10,000 cases of invasive type A streptococcal disease in the United States. Of these, about 7 percent were toxic shock and flesh-eating bacteria.
“Both of these are lethal in less than 50 percent of the cases,” Cleary said of the two invasive diseases.
More common are the several million cases each year of strep throat and impetigo, a skin infection found on people living in warm climates. Type A streptococcus is also responsible for scarlet fever and rheumatic fever, which can cause heart problems in young people.
Type B streptococcus can cause meningitis, blood infections and pneumonia in newborn infants.
University researchers are continuing tests on mice, and leaving human testing to Wyeth-Ayerst.
“We are working on the project and preparing two human clinical evaluations,” said Wyeth-Ayerst spokesperson Doug Petkus. “I can’t provide any definitive time line on the project.”
Mickie Barg covers the Medical School and welcomes comments at mbarg[email protected]