Despite being able to improve surveillance and prevent spread to some extent, these measures have severely impacted economies and livelihoods, and the path towards regaining normalcy involves achieving herd immunity against the virus either naturally or through mass vaccination.
As part of a body’s natural immune response, NAbs are generated by either exposure to the virus or a vaccine. For effective prevention of viral infections, NAbs must be generated in sufficient quantities.
The number of NAbs present in individuals indicates if they possess protective immunity to the virus and their probability of experiencing severe outcomes should they be infected.
NAb testing can determine whether vaccinated individuals should be considered for booster shots for additional protection against the virus.
Though various COVID-19 diagnostic tests are available, the detection of SARs-CoV-2 NAbs is still generally conducted at hospitals and specialized diagnostic laboratories.
Currently, NAbs are commonly detected using virus neutralization tests (VNTs), which require handling of live virus, a facility with rigorous biosafety and containment precautions, skilled personnel, and 2 to 4 days of processing time.
Thus, these tests are not viable for large population testing and surveillance due to the lengthy process that may put a strain on existing laboratory capabilities.
The development of a more efficient means of testing better allows for immediate point-of-care testing and mass monitoring for events or workplaces, specific localities, high traffic points, and critical points of entry such as immigration checkpoints.
“With the gradual opening up of borders, economies, and society, having the right test, and information will be crucial to not only plan for this future but also ensure that it can be done safely without hampering current efforts to curb the spread of the virus,” said Dr. Megan McBee, Scientific Director at SMART AMR.
According to the research team’s data, which has been published in medical and public health journal Communications Medicine, the newly developed rapid cellulose pull-down viral neutralization test (cpVNT) detects SARS-CoV-2 NAbs in plasma samples within 10 minutes.
This detection test utilizes a vertical flow paper-based assay format and protein engineering technology developed at SMART AMR and the Hadley D. Sikes lab at MIT.
Cellulose was adopted as test material as it is cost-effective and easily manufactured, and to avoid reliance on nitrocellulose, which is in high demand due to its use in other rapid COVID-19 tests.
The developed test is simple to administer, non-invasive, and offers quick results. To perform the test, a user mixes a drop of fingertip blood with the reaction solutions and places it on a paper strip, before inserting it into a portable reader device that will detect the NAb signals and reflect the results.
This test offers up to 93% accuracy, higher than similar lab-based methods currently being used.
Besides detecting immunity to the current vaccine version of the COVID-19 virus, the NAb test can be modified to monitor immunity against the other variants of the virus.
This can provide information on the potential efficacy of different vaccines against each variant, or whether one should travel to areas that may have a high incidence of a specific variant.
Further development of the test is underway for its approval by regulatory authorities and manufacturing for public use.
Source: Medindia
