COVID-19 Scan for Nov 18, 2020

News brief

Duke says testing program prevented campus COVID-19 outbreaks

Duke University's aggressive pooled surveillance COVID-19 testing program enabled large-scale testing, successfully reduced transmission, and prevented major outbreaks seen on other college campuses, according to a Morbidity and Mortality Weekly Report (MMWR) study yesterday.

The Duke campaign relied on a combination of strategies, including a 14-day pre-arrival self-quarantine for all enrolled students and a code-of-conduct pledge to wear masks, follow physical distancing guidelines, and undergo regular COVID-19 testing. Daily symptom monitoring—carried out via a custom smartphone app—was accompanied by contact tracing and quarantine. On-campus students were tested twice a week with self-swab kits collected at strategically located sites on campus. Off-campus students were tested once a week.  

The surveillance testing used pooled samples to conserve resources, and the researchers reported positive results with testing samples in batches of five and re-testing individual samples within batches that showed a positive result. The batch method allowed the Duke Human Vaccine Institute to process 80,000 samples from Aug 2 to Oct 11, including 68,913 specimens from 10,265 graduate and undergraduate students—excluding 781 student-athletes who participated in a separate surveillance program.

The Duke surveillance approach resulted in a lower average per-capita infection prevalence among students (0.08%) than in the surrounding community (Durham County, 0.1%), and no large campus outbreaks. There were 84 COVID-19 cases among students, with 51% of the cases occurring among asymptomatic people, highlighting the importance of comprehensive versus symptom-based testing.

"By late summer there were still things we didn't fully understand about SARS-CoV-2 transmission, so there was some uncertainty going into the fall semester," said Steve Haase, PhD, of Duke University School of Medicine in a Duke Health news release yesterday. "Over the course of the semester we've learned many things, including that it is possible to limit the spread of the virus and create a safer environment for our students to have that invaluable on-campus learning experience." 
Nov 17 MMWR study
Nov 17 Duke Health news release


Smartwatch data may help identify pre-symptomatic COVID-19

A study in Nature Biomedical Engineering today shows that smartwatches and other wearable devices may detect pre-symptomatic COVID-19 infection and allow for early-stage interventions that reduce transmission.

Among infected smartwatch users, 81% showed alterations in their heart rate, number of daily steps, or time asleep. Changes before symptom onset identified 63% of the COVID-19–positive individuals, showing that consumer wearable device data can recognize pre-symptomatic infection.

Stanford University researchers analyzed data from 4,642 smartwatch users, focusing on 32 COVID-19–positive participants with Fitbit data that captured resting heart rate (RHR), steps per day, and sleep duration.

Of individuals with a symptom-onset date or a diagnosis date, 88% (22 out of 25) and 100% (25 out of 25) showed a 7-beats-per-minute median elevation in RHR relative to baseline both in advance of and at the time of symptom onset or diagnosis. Elevated signals were detected several days ahead of symptom onset and diagnosis—4 days and 7 days, respectively—highlighting the potential for early identification of infection and mitigation of community spread.

Steps per day significantly decreased and sleep duration increased after the onset of elevated heart rate signals, but no association was found between the magnitude of the increased heart rate signal and specific symptoms, illness length, or temperature.

The researchers also developed an online detection method using smartwatch data to explore the potential detection of early stage COVID-19 illness in advance of symptoms, finding that they were able to detect 63% of known COVID-19 infections.

"Our findings suggest that activity tracking and health monitoring via consumer wearable devices may be used for the large-scale, real-time detection of respiratory infections, often pre-symptomatically," the authors concluded.
Nov 18 Nat Biomed Eng study

News Scan for Nov 18, 2020

News brief

Childhood vaccine uptake down 26% this year, report estimates

Nine million childhood vaccines are projected to be missed by the end of this year in the United States—a 26% decrease compared with 2019—according to a Blue Cross Blue Shield Association (BCBSA) report. This decline would cause a gap between vaccination rate and that required for herd immunity of 4.8 percentage points for measles and 12.7 percentage points for pertussis (whooping cough). Polio would still maintain a 2.9-percentage-point buffer.

According to BCBS medical claims, both measles, mumps, and rubella (MMR) and diphtheria, tetanus, and pertussis (DtaP) childhood vaccination rates dropped 26% January through September year-over-year, with a predicted 2020-end rate of 88.2% and 79.3%, respectively. That compares with herd immunity requirements of 93.0% and 92.0%, respectively, according to the Centers for Disease Control and Prevention.

Polio vaccination rates went down 16% from 2019 and have an 88.9% coverage prediction for 2020, but the BCBSA does not specify why the decline was less for this vaccine.

In a BCBSA survey of 2,000 parents, 40% cited COVID-19 disruptions as the reason they did not complete their child's vaccinations. Most postponements occurred during the pandemic's onset, March through May, and then again in August, when normally vaccinations would be part of the back-to-school routine.

"The U.S. is on the precipice of a severe immunization crisis among children," said Vincent Nelson, MD, BCBSA chief medical officer, in a press release. "The COVID-19 pandemic has significantly interrupted adherence to vaccination schedules, and the possibility that preventable diseases, like polio, could become a threat to public health once again is particularly concerning."
Nov 18 BCBSA press release
Nov 18 BCBSA infographic


CARB-X to fund development of monoclonal antibody for biofilm infections

CARB-X announced today that it is awarding up to $2.42 million to Clarametyx Biosciences of Columbus, Ohio, to develop a monoclonal antibody treatment for serious infections caused by bacterial biofilms.

The money from CARB-X (the Combating Antibiotic Resistant Bacteria Biopharmaceutical Accelerator) will help fund preclinical development of CMTX-101, a monoclonal antibody designed to rapidly collapse bacterial biofilms by targeting a region of DNABII-binding proteins that help stabilize and maintain biofilm integrity.

Biofilms are communities of microbes that can grow on medical devices and human tissue and form a protective layer around bacteria. They are highly resistant to antibiotics and the immune system and are therefore difficult to treat.

"Bacterial biofilms are a serious global health concern due to their ability to resist both antibiotics and the host’s immune system," Erin Duffy, PhD, director of research and development at CARB-X, said in a press release. "We urgently need new therapeutics to address life-threatening bacterial infections. Clarametyx is developing an exciting new approach that could be effective against a broad range of serious drug-resistant pathogens and also numerous types of infections."

Clarametyx will be eligible for an additional $11.85 million if it meets project milestones.

Since launching in 2016, CARB-X has awarded more than $259 million to 73 projects focused on antibiotic-resistant bacteria.
Nov 18 CARB-X press release


H5N8 avian flu sparks more outbreaks in European poultry, wild birds

Three European countries—Denmark, Germany, and the Netherlands—reported more highly pathogenic H5N8 avian flu outbreaks in wild birds and poultry, according to the latest notifications from the World Organization for Animal Health (OIE).

Denmark reported an event at a poultry farm in Randers, located in the central part of the country. It began on Nov 15 and killed 1,500 of 25,000 susceptible birds, and the rest were slated for culling.

Germany reported 19 detections in wild birds, all in Lower Saxony state, which had reported one earlier detection. The events began from Nov 2 to Nov 13, and 16 of 19 infected waterfowl and seabirds died.

The Netherlands reported new H5N8 outbreaks in both poultry and wild birds. The poultry outbreak began on Nov 12 at a commercial farm in Gelderland province in the east central part of the country. The virus killed 3,840 of 22,040 birds, and the rest were destroyed to curb the spread of the virus. Also, the country reported two more events in wild birds, both in South Holland province in the southwest. Between the two events, five mute swans were found dead.
Nov 18 OIE report on H5N8 in Denmark
Nov 17 OIE report on H5N8 in Germany
Nov 17 OIE report on H5N8 in Dutch poultry
Nov 17 OIE report on H5N8 in Dutch wild birds

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