COVID-19: Self-Collected Midnasal Swabs / Vaccine by December? / Prolonged Viral Shedding in Pregnancy / Rapid Acceleration of Diagnostics

By Amy Orciari Herman

Edited by Susan Sadoughi, MD, and Richard Saitz, MD, MPH, FACP, DFASAM

Take a look at some of the latest developments in COVID-19:

Self-collected midnasal swabs: Midnasal swab specimens self-collected at home may be comparable to clinician-collected nasopharyngeal swab specimens for detecting SARS-CoV-2 in symptomatic patients, a JAMA Network Open study suggests. Nearly 200 symptomatic patients — 85% of whom were health care workers — contributed both types of specimens for analysis. About one fifth had a positive result on at least one specimen. With the clinician-collected swabs as the reference, home swabs had a sensitivity of 80% and specificity of 98%. Among the 28 true positives detected at home, the specimen was self-collected a median of 4 days after symptom onset; among the 7 false-negatives at home, the specimen was collected at a median of 6 days. The authors acknowledge study limitations but write, "This approach is safe and scalable in the pandemic setting, permitting widespread testing of symptomatic participants early in illness and the potential for prompt self-isolation and [contact] tracing."

Vaccine by December? The U.S. Department of Health and Human services on Tuesday announced an agreement with Pfizer to produce up to 600 million doses of vaccine against SARS-CoV-2, pending safety and efficacy results from a phase 3 trial and subsequent emergency use authorization from the FDA. If the vaccine is authorized, HHS said, Pfizer could begin delivering the vaccine "to locations at the U.S. government's direction" in the final quarter of 2020. Entering into the agreement now will expedite shipping later, HHS said. The vaccine is currently in phase 1/2 trials.

Prolonged viral shedding in pregnancy: A 27-year-old woman with COVID-19 during pregnancy had SARS-CoV-2 RNA detected in her nasopharynx for over 100 days, according to a case report in Obstetrics & Gynecology. The woman presented with mild symptoms and tested positive at roughly 28 weeks' gestation; her symptoms resolved within 3 days. She tested positive again during labor at 38 weeks' gestation — and then again 5 weeks later, a full 104 days after her initial positive test result. The researchers conclude that "a positive screening SARS-CoV-2 test in the asymptomatic pregnant patient should be interpreted with caution. ... positivity does not necessarily represent acute asymptomatic or presymptomatic infection." They add that "there may be a role for antibody testing ... as part of a universal screening protocol."

Rapid Acceleration of Diagnostics: A special report in the New England Journal of Medicine details the National Institutes of Health's Rapid Acceleration of Diagnostics (RADx) initiative, which aims to "support the development, production scale-up, and deployment of accurate, rapid [SARS-CoV-2] tests across the country." One goal is to enable 2% of the U.S. population to be tested per day by December 2020. Read more at the link below.