Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Developer of anthrax quick test finds similar test for strep throat

29.07.2002


The culprit in bacterial streptococcus pharyngitis, or strep throat, can be vicious. Ask a parent who suspects their child has caught the virus, or the family of 29 Texans, including nine children, who died in 1997 after the bacteria manifested itself into a flesh eating disease. This virulent disorder used to cause physicians to order patients to immediately start taking antibiotics – even when a bacterial origin had not been established.



But taking antibiotics when not needed reduces the curative effects of antibiotics. That is why physicians applauded the introduction of the Rapid Streptococcal Antigen Test or the "rapid strep" test. Research indicates that this test, which takes about 20 minutes, is just as accurate as the much slower culture analysis. (If the rapid test is not clearly negative and symptoms exist, a doctor may also perform a regular culture.)

Advocates claim the rapid test is 80 to 90 percent sensitive in detecting group A beta-hemolytic streptococcus in throat swabs and 90 to 95 percent specific in eliminating streptococcal infection as a consideration in rapid test-negative patients. Detection of streptococci by rapid antigen tests or throat culture has consistently been shown to be a cost-effective strategy in the management of sore throat, independent of the issues surrounding antibiotic overuse.


But the leader of a team that developed a rapid test for anthrax exposure has completed an assessment of various testing procedures used in the rapid test and found the results wanting. He suggests that rapid antigen testing lacks sensitivity, negative results require a back-up culture and that its sensitivity may be declining. One alternative is rRNA (ribosomal ribonucleic acid) testing which has enhanced sensitivity but is still not as effective as a culture. His conclusion is that assessing PCR (polymerase chain reaction) using the same principle and diagnostic equipment in a proposed test for anthrax may offer the best test for bacterial strep throat.

The Study

Presenting “Rapid Testing for Streptococcal Infection: How Effective Is It?” is physician Franklin R. Cockerill III, Professor and Chair, Microbiology, Mayo Clinic and Mayo Medical School, Rochester, MN. His comments will be offered at the 54th Annual Meeting of the American Association for Clinical Chemistry (AACC). AACC (http://www.aacc.org/) is the scientific organization for clinical laboratory professionals, physicians, and research scientists. Their primary commitment is the understanding of laboratory testing to identify, monitor and treat human disease. More than 11,000 attendees are expected for the meeting, which is being held at the Orange County Convention Center, Orlando, FL, July 28-August 1, 2002.

Background

The most common manifestation of Group A streptococcus is “strep throat,” due to bacterial pathogens. Group A is responsible for 15-30 percent of cases reported. Characteristic symptoms are sudden onset of sore throat, pain on swallowing, fever, headache, abdominal pain, nausea and vomiting; uncharacteristic symptoms include hoarseness, cough and diarrhea. The signs of the disease are redness and signs of pus in the throat.

The Preferred Test

Dr. Cockerill proposes “Rapid-cycle real time PCR” as the preferred test for bacterial streptococcus pharyngitis. PCR, or polymerase chain reaction, is an enzymatic method for the repeated copying and amplification of the two strands of DNA of a particular gene sequence. It is widely used in the detection of HIV.

He believes the LightCycler® instrument for polymerase chain reaction (PCR)-based assays is the optimum diagnostic equipment to detect streptococcus group A bacterium, and is also suggested for anthrax detection. In comparing the Group A Streptococcus LightCycler® assay against the antigen/culture method, he found:


Processing and analytical time for 32 samples (specimens and controls) were 1.5 hours for PCR and up to 2 days for the antigen/culture method.
Personal time for administering the LightCycler® test was three minutes and seven minutes for the antigen/culture procedure.
Sensitivity was higher in all categories when compared against cultures (except an equal measure for legionella).

Conclusion

Dr. Cockerill finds that, when compared to cultures, time to process LightCycler® assays were significantly shorter than culture based tests.


Editor’s Note: To interview Dr. Cockerill, please contact Donna Krupa at 703.527.7357 (direct dial), 703.967.2751 (cell) or djkrupa1@aol.com.
Or contact the AACC Newsroom at: 407.685.4215.


Donna Krupa | EurekAlert!

More articles from Health and Medicine:

nachricht Nanoparticles as a Solution against Antibiotic Resistance?
15.12.2017 | Friedrich-Schiller-Universität Jena

nachricht Plasmonic biosensors enable development of new easy-to-use health tests
14.12.2017 | Aalto University

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>