Scientists with the U.S. Department of Agriculture's Agricultural Research Service (ARS) have developed a new test that's faster, more sensitive and less expensive than current tests for detecting the foodborne toxin staphylococcal enterotoxin type E (SEE).
The bacterium Staphylococcus aureus, which makes a variety of toxins, is one of the most common causes of food poisoning. SEE has been associated with outbreaks in the U.S. and other countries.
In the U.S., staphylococcal food poisoning causes an estimated 240,000 illnesses, 1,000 hospitalizations and six deaths annually, according to the Centers for Disease Control & Prevention.
ARS chemist Reuven Rasooly and his colleagues at the ARS Western Regional Research Center in Albany, Cal., developed a T-cell test that specifically detects SEE in foods. T-cells are a type of white blood cell that helps with the body's immune system response.
The current method for detecting SEE toxins is an animal model, which is expensive, has low sensitivity and is difficult to reproduce, ARS said. Other tests used to detect toxins cannot distinguish between active toxin — which does pose a threat to public health — and inactive toxin, which does not.
The animal model test detects active toxin only 50% of the time compared to the new T-cell test, which detects it 100% of the time. The T-cell test also detects toxin within five hours versus 48-72 hours for other tests, ARS said.
The T-cell test can be used by food makers to help keep products safer before they're sold and by public health officials to trace the source of foodborne illness outbreaks.
ARS has filed a patent application for the new T-cell test.