No more throat cultures for respiratory infection diagnosis
Microbiological testing currently takes time and money, with typical results needing a day or more following throat culture from a cotton swab. However, use of antibiotics without testing is undesirable for a number of reasons and causes problems that could be avoided with low-cost, rapid assays. First, infections caused by viruses and not by bacteria do not respond to antibiotics. Viral pathogens causing respiratory illness are numerous including influenza A and B, adenovirus and respiratory syncytial virus (RSV) whereas bacterial pathogens are primarily streptococcus A and B. In addition, ineffective yet prolonged administration of antibiotics can foster the growth of resistant strains of bacteria making future treatment of illnesses problematic. In fact, as a result of just such an effect, specific bacteria typically respond to specific antibiotics and not to others. In all cases, overuse of antibiotics can harm the normal balance of flora in the patient’s digestive tract. European researchers with funding for the ‘Multiplex bioassays using the two-photon excitation method’ (Biotphex) project developed a rapid, on-site (in the doctor’s office) bioassay for respiratory pathogens. The technology was based on the two-photon excitation (TPX) methodology developed for three-dimensional (3D) in vivo imaging of cells and tissues and using fluorescent biomarkers for specific pathogens. The TPX detection technique promises to eliminate unnecessary prescription of antibiotics by differentiating between viral and bacterial pathogens and allowing effective prescription of pathogen-specific medication. Further, technology led to development of a rapid bacterial antibiotic sensitivity test, facilitating prescription of the appropriate antibiotic for a given bacterial pathogen. The prototype was successfully tested and specificity demonstrated in samples containing staphylococcus aureus and streptococcus pyogenes in high background levels of non-bacterial constituents. Commercialisation of the low-cost and rapid Biotphex assays should eliminate hesitance on the part of doctors to conduct microbiological testing. Its widespread use may also encourage patients in some countries not to self-medicate given the ease with which pathogen-specific medication can be prescribed. Biotphex results could have significant impact on patient health, healthcare costs and development of antibiotic-resistant strains of bacteria.
