Monday, October 31, 2022

Point-of-Care Test Identifies Bacterial and Viral Causes of Acute Respiratory Infections

A point-of-care test shows good sensitivity for identifying both bacterial and viral pathogens in patients with acute respiratory infections.

A point-of-care test has been found to correctly distinguish between bacterial and viral infections based on the host’s immune response, among patients with acute respiratory infections according to the results of a diagnostic study by team of US researchers.

Respiratory symptoms are the motive for a third of emergency room visits by both adult and paediatric patients. Acute respiratory infections due to either acute bronchitis, sinusitis, pneumonia and the common cold often present with overlapping symptoms leading to over-prescribing of antibiotics. Although multiplex PCR systems are available for the identification of bacterial and viral pathogens, an alternative strategy is to use a point-of-care test based on the host’s immune response to myxovirus resistance protein A (MxA) and C-reactive protein (CRP) in a finger-stick whole blood sample. To test the value of this approach in helping clinicians to decide on whether or not to prescribed antibiotics, in the present study, the US team examined the ability of the FebriDx® which is a rapid, point-of-care diagnostic test that is designed to aid in the differentiation of bacterial and viral acute respiratory infections. The test can provide a result within 10 minutes by identifying myxovirus resistance protein A, which is induced by type 1 interferon due to viral infections and CRP, a non-specific acute-phase protein produced in response to inflammation and infection. While CRP is not specific for bacterial infections, if only MxA levels are elevated (i.e., no change in CRP) this is indicative of a viral infection. Similarly, elevated CRP in the absence of MxA, indicates a bacterial infection.

The US team recruited patients from emergency departments and outpatient settings who presented with new-onset respiratory symptoms including rhinorrhoea, nasal congestion, sore, throat, hoarseness, cough or shortness of breath and a recent fever and an asymptomatic control group. The point-of-care test was administered to both groups of patients although the treating physicians were blind to the test results. The primary outcome was set as a bacterial or viral-associated systemic host response. In addition, patient samples were collected and analysed by multiplex PCR for either viral or bacterial identification and which served as independent assessment of the point-of-care test result.

Point-of-care test and bacterial or viral identification

A total of 520 symptomatic patients with a mean age of 35.3 (44.2% male) were included and 170 in the asymptomatic group.

Final diagnostic information was available for 496 individuals and of whom, 14.7% had a confirmed bacterial and 59.7% a viral infection with the remainder classed as negative. The point-of-care test correctly identified 93.1% of bacterial infections giving a sensitivity of 93.2% (95% CI 84.9 – 97%), a specificity of 88.4% (95% CI 85 – 91.1%) and a positive predictive value of 58.1%.

For viral infections, the point-of-care test had a sensitivity of 70.3% (95% CI 64.8 – 75.2%), a specificity of 88% (95% CI 82.8 – 91.8%) and a positive predictive value of 89.7%. Interestingly, none of the participants had a co-infection which was defined as both a bacterial and viral pathogen plus a host response based on the independent assessment.

The authors concluded that the rapid diagnostic point-of-care test could help inform clinicians when assessing for either bacterial or viral causes for acute respiratory infections.


Shapiro NI et al. Diagnostic Accuracy of a Bacterial and Viral Biomarker Point-of-Care Test in the Outpatient Setting JAMA Netw Open 2022

Wednesday, October 05, 2022

PRESS RELEASE: Nissui Pharma Solutions Launches its Mycoplasma Detection Kit in EMEA

Nissui Pharma Solutions (NPS), European subsidiary of Nissui Pharmaceutical Japan, commercialises contamination detection kit for the production of cell culture derived biopharmaceutical products. 

MycoFinder, our rapid mycoplasma detection kit, has been validated in accordance with the EP 2.6.7, USP 63 and JP 17 and is now commercially available throughout EMEA. MycoFinder uses real-time fluorescent PCR to ensure sensitive detection (below 10 CFU/mL) of mycoplasma. The kit is simple and quick to implement for product screening and batch release in laboratories where time is of the essence.

MycoFinder: sensitivity, simplicity and speed 

MycoFinder is in a PCR tube strip format with all the components of the Master Mix freeze-dried in each PCR tube. This allows preparation of PCR reactions in minutes, the Master Mix is resuspended simply by adding 25┬ÁL of DNA sample directly into the tubes. 

The kit is compatible with most commercially available thermocyclers due to two formats of PCR strips (white and clear). The ease of use of the MycoFinder kit, combined with the optimised Master Mix, results in PCR data in less than one hour.

For more information, please visit

Christopher Tarabay

Commercial Director NPS

DNA Nets Capture COVID-19 Virus in Low-Cost Rapid-Testing Platform

Tiny nets woven from DNA strands can ensnare the spike protein of the virus that causes COVID-19, lighting up the virus for a fast-yet-sensitive diagnostic test – and also impeding the virus from infecting cells, opening a new possible route to antiviral treatment, according to a new study.

Researchers at the University of Illinois Urbana-Champaign and collaborators demonstrated the DNA nets’ ability to detect and impede COVID-19 in human cell cultures in a paper published in the Journal of the American Chemical Society. 

“This platform combines the sensitivity of clinical PCR tests and the speed and low cost of antigen tests,” said study leader Xing Wang, a professor of bioengineering and of chemistry at Illinois. “We need tests like this for a couple of reasons. One is to prepare for the next pandemic. The other reason is to track ongoing viral epidemics – not only coronaviruses, but also other deadly and economically impactful viruses like HIV or influenza.”   

DNA is best known for its genetic properties, but it also can be folded into custom nanoscale structures that can perform functions or specifically bind to other structures much like proteins do. The DNA nets the Illinois group developed were designed to bind to the coronavirus spike protein – the structure that sticks out from the surface of the virus and binds to receptors on human cells to infect them. Once bound, the nets give off a fluorescent signal that can be read by an inexpensive handheld device in about 10 minutes.

The researchers demonstrated that their DNA nets effectively targeted the spike protein and were able to detect the virus at very low levels, equivalent to the sensitivity of gold-standard PCR tests that detect the virus’s genetic material but can take a day or more to return results from a clinical lab.

The technique holds several advantages, Wang said. It does not need any special preparation or equipment, and can be performed at room temperature, so all a user would do is mix the sample with the solution and read it. The researchers estimated in their study that the method would cost $1.26 per test.  

“Another advantage of this measure is that we can detect the entire virus, which is still infectious, and distinguish it from fragments that may not be infectious anymore,” Wang said. This not only gives patients and physicians better understanding of whether they are infectious, but it could greatly improve community-level modeling and tracking of active outbreaks, such as through wastewater.

In addition, the DNA nets inhibited the virus’s spread in live cell cultures, with the antiviral activity increasing with the size of the DNA net scaffold. This points to DNA structures’ potential as therapeutic agents, Wang said.

“I had this idea at the very beginning of the pandemic to build a platform for testing, but also for inhibition at the same time,” Wang said. “Lots of other groups working on inhibitors are trying to wrap up the entire virus, or the parts of the virus that provide access to antibodies. This is not good, because you want the body to form antibodies. With the hollow DNA net structures, antibodies can still access the virus.”

The DNA net platform can be adapted to other viruses, Wang said, and even multiplexed so that a single test could detect multiple viruses.

“We're trying to develop a unified technology that can be used as a plug-and-play platform. We want to take advantage of DNA sensors’ high binding affinity, low limit of detection, low cost and rapid preparation,” Wang said.

The National Institutes of Health supported this work through the Rapid Acceleration of Diagnostics program. The researchers will continue to work through the RADx program to explore and accelerate clinical applications for the DNA net platform.

Wang also is affiliated with the Holonyak Micro and Nanotechnology Lab and the Carl R. Woese Institute for Genomic Biology at Illinois.

The paper “Net-shaped DNA nanostructures designed for rapid/sensitive detection and potential inhibition of the SARS-CoV-2 virus” is available at