Scientists at the University of Veterinary Medicine, Vienna (Vetmeduni Vienna) use infrared light and artificial intelligence, to present the method for the prediction of disease progression.
The study demonstrates that artificial neuronal network (ANN)-assisted Fourier Transform infrared (FTIR) spectroscopy allows a rapid and reliable discrimination of S. aureus capsular serotypes.
Tom Grunert et al have developed a method by which the capsules can quickly and clearly be distinguished from one another without the use of antibodies.
Infrared light is shone on the microorganisms to be tested and the resulting spectral data inputted into a supervised self-learning system, an artificial neuronal network which uses the data to work out the type of capsule.
99% success rate
The researchers claim that with the new method they can routinely test patient samples with a success rate of up to 99%.
Aggressive types of S. aureus form capsules and multiply rapidly but are also quickly recognized by the immune system while capsule-free forms are better able to survive within cells and are less well recognized.
The researchers described this as “hide and seek” before they attack and so are more likely to cause chronic infections that are harder to treat.
S. aureus was previously detected and the nature of its capsule checked by means of specific antibodies that bind the capsule.
The procedure is relatively complex, as the antibodies are not commercially available and have to be produced in animal experiments, explained the researchers.
Staphylococcusaureus in food
Staphylococcus aureus has the ability to make seven different toxins that are frequently responsible for food poisoning, according to the US Centers for Disease Control and Prevention (CDC).
The most common way for food to be contaminated is through contact with food workers who carry the bacteria or through contaminated milk and cheeses, said the agency.
Monika Ehling-Schulz, the head of Grunert’s institute, said: "In principle, germs have two choices when they infect a host: attack or hide – in technical terms virulence or persistence.
“If they attack, they risk destroying the host and consequently themselves, whereas if they hide, they may be outcompeted by others.
“A detailed knowledge of the mechanisms of virulence and persistence and the way bacteria switch between them will help us to develop novel and more effective therapies."