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People with symptoms that sought the COVID-19 test could be effectively swabbed at home, and the results of such tests were found to be comparable to those involving conventional nasopharyngeal wipes by clinicians. Suggests new research.
Household swab tests showed 80% sensitivity and 98% specificity for the detection of SARS-CoV-2 compared to tests performed by clinicians.
“Timely testing should be a priority because there are still many cases throughout the United States,” said Dr. Helen Y. Chu, senior research author. Medscape Medical News.. Household tests can also supplement traditional types of tests.
Professor Chu, a professor of medicine in the Department of Allergies and Infectious Diseases at the University, further added, “Self-collected swabs at home are a way for individuals to get tested quickly and accurately without having to leave the house to expose others. Will be provided.” Of the Washington Medical School in Seattle.
Findings published online on July 22 Research letter To JAMA network open.
Previous research reported in JAMA Network Open On June 12, a good agreement between COVID-19 patient wipes and clinician wipes was also revealed. inside that Investigation Of the 30 participants, researchers at Stanford University in California reported that samples taken by patients were 100% sensitive and 95% specific.
To compare these approaches in a larger population, the researchers evaluated 185 people, including healthcare professionals, seeking the COVID-19 test.
They used a custom designed self-swab test. This kit includes Copan FLOQSwab, BD Universal Transport Media, and other off-the-shelf individual components. Researchers issued an instruction sheet on the creation of the test kit on July 9. New England Medical Journal (Supplementary Figure 2).
Positive correlation
Overall, the test confirmed positive results in 41 out of 185 participants (22%). Most of the participants-85%-were healthcare workers. Within this group, 14 (9%) were SARS-CoV-2 positive.
Chu and colleagues report a “substantial agreement” between the two forms of testing, reflected by the Cohenkappa coefficient of 0.81.
In addition, the home swab cycle threshold (a measure of viral load) was positively correlated with the clinician swab (correlation coefficient, 0.81; P <.001). At high viral loads (defined as a cycle threshold of 32 or less), the sensitivity of household swabs increased to 95%.
When asked if the similar accuracy of the two test approaches was unexpected, Chu said: Previous studies have shown that other respiratory pathogens include: influenza, Collected.
PPE savings, early detection?
“Unsupervised home self-swab collections have several benefits, such as external access to healthcare systems and minimal use of personal protective equipment,” the researchers say. “This approach is safe and scalable in a pandemic environment, allowing symptomatic participants to be extensively tested early in the disease, with the potential for rapid self-isolation and contract tracking.”
Home-based strategies should “target early-stage individuals with illness who have the highest risk of infection and are unlikely to care,” they added.
Since most participants were health care providers, one of the limitations of the study was generalizability to the general public. “Remarkably, the majority of participants in this study are healthcare professionals themselves, and whether they can do a better job in collecting samples compared to the general public. Is questioning,” said the Director of Pathology and Laboratory Medicine at the North Shore University Health System in Evanston, Illinois. Medscape Medical News When asked to comment on a study.
“Clinicians are accustomed to the process of swabs and are likely to have a better understanding of how to properly take swabs,” Chu said. “But people are pretty good at following their instructions and collecting their swabs.”
“This encouraging, but small, study examined the accuracy of self-collected intranasal samples to detect COVID compared to gold standard nasopharyngeal swabs collected by health care workers,” Kaul said. He says. This strategy will enable broader public testing and reduce the need for personal protective equipment and health care professionals who are “neither currently”.
“The data showed that self-collecting samples yielded positive results in 80% of the positive samples—20% were overlooked, probably due to the fact that mid-nasal and nasopharyngeal swabs were being compared The swab’s sensitivity is rather low.” She suggested performing the assay on the platform with good sensitivity to ensure that fewer cases were missed.
When asked if self-swabs are available at the drive-thru COVID-19 test site, he said, “Yes, I believe swabs can generalize results to any place where they are self-collected. The collection is expected to have the same level of accuracy if the instructions provided at these drive-through test sites are clear and concise.”
Additional restrictions include potential sample degradation due to ambient temperature shipments, and timing differences in sample collection between groups — the self-swab cohort took a day longer. The timeline may have affected viral load levels, the researchers say.
Multiple research plans
“We have begun a large-scale study investigating response to an outbreak, which has led to “non-contact” contact tracking in this way,” Zhu said of future work.
We also plan to use a biorepository of blood samples from people with confirmed SARS-CoV-2 infection to compare viral load to antibody levels.
Chu et al. analyzed a swab sample taken within 48 hours of a positive test and found changes in viral load and viral shedding over time compared to swabs taken every 2-3 days from the same patient for 2 weeks. Evaluate
Unanswered question
The study “raises important questions to investigate further,” said Dr. Zvi G. Loewy, vice president of pharmaceutical and biomedical research at Toro University of Pharmacy in New York City. Medscape Medical News When asked for a comment.
“We are in the age of personalized medicine,” Ruwi said. “Diabetics routinely test blood glucose levels. It is very possible for patients to collect their own specimens for the COVID-19 test, if the collection of specimens is properly designed.”
Unanswered questions from the study included whether self-collection minimizes COVID-19 exposure, and whether self-testing actually promotes testing overall, he said. Regarding study design, Loewy proposed a similar study in the future to adopt a crossover design and compare two samples of each individual.
Chu and Loewy do not disclose related financial relationships.
JAMA Netw Open.. Published July 22, 2020 Online. Full text
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