COVID-19 Scan for Feb 24, 2021

News brief

COVID-19 antibodies may offer at least partial protection

Americans with COVID-19 antibodies displayed 10-fold increased protection against infection 90 days after testing compared with those who had no antibodies, according to a study published today in JAMA Internal Medicine.

The study tracked more than 50% of the commercial antibody and diagnostic tests administered in the United States from Jan 8 to Aug 23, 2020, covering 3,257,478 people. At the index test, 88.3% had a negative antibody test, 11.6% were positive, and 0.1% were excluded because of uncertain results.

The researchers then followed the seropositive and seronegative groups for a median of 54 and 47 days, respectively. During this time, 41,587 (11.0%) of seropositive individuals and 273,735 (9.5%) of seronegative individuals received at least one nucleic acid amplification test (NAAT), most commonly polymerase chain reaction (PCR).

While 11.3% of this seropositive subgroup had a positive NAAT during days 0 to 30, most likely due to continued viral RNA shedding, the prevalence declined to 2.7% from days 31 to 60, 1.1% from days 61 to 90, and 0.3% beyond day 90. Across each period, about 3.0% of the seronegative group had positive NAAT results.

In other words, the ratio of positive NAATs in seropositive versus seronegative people declined from 2.85 (95% confidence interval [CI], 2.73 to 2.97) during the first 30 days to 0.10 (95% CI, 0.05 to 0.19) after day 90. Because some of the positive NAATs after day 60 could be reinfections in the seropositive group, the researchers note, "Protection against reinfection is likely relative rather than complete."

"The data from this study suggest that people who have a positive result from a commercial antibody test appear to have substantial immunity to SARS-CoV-2, which means they may be at lower risk for future infection," says lead researcher Lynne Penberthy, MD, MPH, in a National Cancer Institute (NCI) press release.

In an editor's note, Mitchell Katz, MD, of NYC Health and Hospitals, writes that, despite the findings, "Vaccination against SARS-CoV-2 is recommended regardless of antibody status."
Feb 24 JAMA Intern Med study
Feb 24 JAMA Intern Med editor's note
Feb 24 NCI
press release


Empathetic calls associated with better mental health during pandemic

An empathy-focused telephone program was associated with reduced loneliness, depression, and anxiety in 120 Meals on Wheels Central Texas clients, according to a study published yesterday in JAMA Psychiatry.

From Jul 6 to Sep 24, 2020, the researchers had 120 people receive daily telephone calls for the first 5 days and then, depending on preference, at least twice a week for a total of 4 weeks. After the first 5 days, 58.3% of the intervention group chose to continue the daily calls, followed by 22.5% choosing twice a week. The 120 people in the control group received no calls.

All study participants had at least one chronic condition, and 63% were at least 65 years old. More than half (56.3%) were living alone. Thirteen people in the intervention group and 1 in the control group were lost to follow-up, so the final data were for 107 and 119, respectively.

Callers received 1 hour of video conference training, handouts, and videotaped instructions on conducting conversations led by the recipient's interests. While these conversations were intended to be less than 10 minutes, some went longer.

When comparing the intervention and control groups, the intervention group improved 1.1 points on the UCLA Loneliness Scale (95% confidence interval [CI], 0.5 to 1.7), 0.32 point on the De Jong Giervald Loneliness Scale (95% CI, -0.20 to 0.81, not statistically significant), 1.5 points on the Personal Health Questionnaire for Depression (95% CI, 0.22 to 2.7), and 1.8 points on the Generalized Anxiety Disorder scale (95% CI, 0.44 to 3.2). Overall, the intervention group's self-assessed mental health score via the Short Form Questionnaire Survey increased 2.6 points relative to the control group (95% CI, 0.81 to 4.4).

"In this study, loneliness, depression, and anxiety were rapidly reduced through layperson-delivered calls that focused on empathetic listening, suggesting a scalable approach to persistent mental health challenges of older adults," the researchers write. "Future work should address whether improvements can be sustained, or enhanced, with a longer implementation period."
Feb 23 JAMA Psychiatry study

News Scan for Feb 24, 2021

News brief

ECDC finds low threat to humans from H5N8 avian flu

The European Centre for Disease Prevention and Control (ECDC) today issued a risk assessment regarding human H5N8 avian flu cases reported recently in Russia, with the caveat that it was basing its report on very limited data.

Russia recently reported seven infections in people who worked at poultry facilities in the south. They reportedly had asymptomatic infections, and no human-to-human transmission was noted.

The ECDC said that, since October, about 1,700 outbreaks in birds involving H5N8 and other avian flu strains have been reported in Europe and neighboring countries.

Currently, the risk is very low for the public and low for people exposed to the virus in occupational settings, the ECDC said. It added that H5N8 remains avian-adapted, with no markers for adaptation to mammals.

So far it doesn't appear to be pathogenic in humans, and the virus remains susceptible to existing antivirals. Disease severity is asymptomatic or mild, so the ECDC assessed the severity impact as very low.
Feb 24 ECDC risk assessment
Feb 22 CIDRAP News story "Russia reports first human H5N8 avian flu cases"


FDA accepts priority review for Pfizer’s tick-borne encephalitis vaccine

Yesterday the Food and Drug Administration (FDA) accepted priority review of TicoVac, Pfizer's tick-borne encephalitis (TBE) vaccine. If approved, TicoVac could be used to prevent active infections in people 1 year and older.

"For many years, our TBE vaccine has helped protect millions of people in Europe from this potentially serious disease. We are proud that today's U.S. FDA Priority Review acceptance acknowledges the potential value that our vaccine candidate can bring," said Nanette Cocero, PhD, the global president of vaccines for Pfizer, in a company press release. "If approved in the U.S., we hope this vaccine will help protect those traveling to or residing temporarily in at-risk locations, potentially including military personnel who are serving overseas."

TicoVac has been approved for use outside of the United States for more than 40 years, and in real-world studies the vaccine prevents disease in 96% to 99% of recipients after two doses. More than 160 million doses of the vaccine have been distributed outside of the United States since 1976.

TBE, which is endemic in parts of Europe and Asia, is a viral infection of the brain and spine. Though it rarely causes death, one third of people with CBE can have long-term effects, including cognitive changes, muscle weakness, or permanent paralysis.

Though TBE is not endemic in the United States, it has been reported in 35 countries. There are no approved treatments for the disease.
Feb 23 Pfizer
press release

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