This week brings positive news regarding schools, vaccines, and cases in the U.S.. Case counts have plateaued at a level similar to August of last year. Meanwhile, vaccinations rates continue to increase and states continue to loosen criteria to receive those vaccines. In Europe, case counts continue to climb in France, Italy, Germany, and Spain but those countries have also had slower progress with vaccinations.
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1) School Temperature Screen Survey
The Learn EM School Survey on temperature screening now has enough data to begin reporting. It is still open to any school or district to report their data confidentially, here. The goal is to ascertain the effectiveness of daily temperature checks in screening for COVID-19.
To date, the survey includes:
- 1556 children, screened daily
- 277 staff and parents, screened daily
- 640 total days of screening
School grade levels included:
- 36% Preschool
- 21% Kindergarten
- 16% Elementary school
- 16% Middle school
- 11% High school
- New York (30%)
- Florida (20%)
- Illinois (10%)
- Iowa (10%)
- Pennsylvania (10%)
- South Carolina (10%)
Participating schools reported
- 182,440 temperature screenings in children
- 35,620 temperature screenings in adults
There were no cases of COVID-19 detected. Additionally, there were only 2 elevated temperatures detected total, both in symptomatic children checked in the afternoon, and neither resulted in a positive COVID-19 test. Despite the temperature screening results, 10% of participating schools had cases of COVID-19 among students and staff within the school.
Based on these results, it is clear that screening of asymptomatic children and adults for the presence of elevated temperature is not effective in detecting cases of COVID-19. Resources devoted to this practice are better used elsewhere.
This summary can be found on the Lean EM website here, and will be updated as more schools share their experience.
2) Schools and Distancing
Speaking of schools, last week the CDC announced its revision to school distancing guidelines. 3 feet is now the standard with universal mask use. However, there are some caveats for middle and high schools that can’t cohort classrooms. The formal guidance strategy states:
- “In elementary schools, CDC recommends all students remain at least 3 feet apart in classrooms where mask use is universal — regardless of whether community transmission is low, moderate, substantial, or high.
- In middle and high schools, CDC also recommends students should be at least 3 feet apart in classrooms where mask use is universal and in communities where transmission is low, moderate, or substantial.
- Middle school students and high school students should be at least 6 feet apart in communities where transmission is high, if cohorting is not possible. Cohorting is when groups of students are kept together with the same peers and staff throughout the school day to reduce the risk for spread throughout the school. This recommendation is because COVID-19 transmission dynamics are different in older students – that is, they are more likely to be exposed to SARS-CoV-2 and spread it than younger children.”
They also note: “CDC continues to recommend at least 6 feet of distance:
- Between adults in the school building and between adults and students.
- In common areas, such as school lobbies and auditoriums.
- When masks can’t be worn, such as when eating.
- During activities when increased exhalation occurs, such as singing, shouting, band practice, sports, or exercise. These activities should be moved outdoors or to large, well-ventilated spaces whenever possible.
- In community settings outside of the classroom.”
3) Those Living With Children Have Increased Risk of COVID?
A study published in the British Medical Journal (BMJ) attempted to answer this question by looking at population data for 12 million people in the U.K. They collected clinic and hospital data from the two large COVID-19 waves in the UK, wave 1 ( February to August 2020) and wave 2 (September to December 2020). They found some interesting results.
- During wave 1, living with children was not associated with increased risks of SARS-CoV-2 infection, covid-19 related hospital or intensive care admission, or death.
- During wave 2, living with children was associated with an increased risk of SARS-CoV-2 infection (hazard ratio 1.06 for living with children aged 0-11 years; 1.22 for living with children aged 12-18 years) and covid-19 related hospital admission (1.18 for living with children aged 0-11; 1.26 for living with children aged 12-18).
Though these differences were statistically significant during the second wave, the study authors appropriately noted that the absolute difference (actual case numbers not ratios) were quite small. In addition, they also noted that there was no significant change in deaths.
So the technical answer is Yes, there was a small increased risk of COVID when living with children in the U.K. during the second wave only, but it was small and did not result in an increased risk of death, making it of questionable clinical significance.
4) Sinovac Vaccine Safe In Children
The Chinese manufacturer Sinovac is reporting “preliminary data” from Phase 1 and 2 trials of its COVID vaccine in children. In an interview with one of the researchers, Reuters reports that the trials included 500 children age 3-17 receiving either 2 medium doses, low doses, or placebo 2 weeks apart. The researcher suggested that antibody levels in children were higher than in adults, and that lower doses may be sufficient. Other reports note that the data has been submitted to Chinese drug regulators. The data has not yet been published in any scientific journal.
5) Astra Zeneca Vaccine Efficacy
Drug manufacturer Astra Zeneca reported results of its phase 3 trial in the US this past week. It reported
- 79% vaccine efficacy at preventing symptomatic COVID-19
- 100% efficacy against severe or critical disease and hospitalization
- Comparable efficacy result across ethnicity and age, with 80% efficacy in participants aged 65 years and over
- Favorable overall safety profile
- 100% efficacy at preventing severe disease and hospitalization.
This interim safety and efficacy analysis was based on 32,449 participants accruing 141 symptomatic cases of COVID-19.
Unfortunately, the National Institute of Allergy and Infectious Disease (NIAID) also released a statement this week noting that the Data and Safety Monitoring Board was concerned these published numbers may be based on old data. The NIAID statement did not clarify exactly which statistic was incorrect. Other media outlets suggested the efficacy should have been reported to be 69-74%.
In response to the NIAID statement, Astra Zeneca updated its report online, which now states the vaccine has:
- 76% vaccine efficacy against symptomatic COVID-19
- 100% efficacy against severe or critical disease and hospitalization
- 85% efficacy against symptomatic COVID-19 in participants aged 65 years and over
These are still excellent numbers. Though the company may have some PR work to do, its vaccine appears to be performing very well. I look forward to the formal release of its trial data when it applies to the FDA for emergency authorization.
6) Vaccines Prevent Asymptomatic Infection
Since the authorization of the Pfizer and Moderna COVID-19 vaccines, researchers have been trying to determine if vaccinated individuals can still spread the virus. This requires testing of vaccinated people and following them over time to see if they develop infections, symptoms, or test positive without symptoms. The assumption is that someone who is vaccinated and tests positive may be able to transmit the virus to others by acting as a carrier without actually becoming infected themselves. This past week, two letters helped shed some light on the question.
First is a letter to the editor titled SARS-CoV-2 Infection after Vaccination in Health Care Workers in California that appeared in the New England Journal of Medicine (NEJM) this past week. The letter details a study of test results from the University of California, San Diego (UCSD) and the University of California, Los Angeles (UCLA) health systems. Both systems began vaccinating health care workers in December, 2020. UCSD mandated its workers be tested weekly and UCLA added a voluntary program for testing workers. The study pooled results from both institutions from December 16, 2020 through February 9, 2021. They found:
- 36,659 health care workers received the first dose of vaccine, and 28,184 of these persons (77%) received the second dose.
- After receiving both vaccinations, 37 health care workers tested positive
- 22 had positive test results 1 to 7 days after the second dose
- 8 health care workers tested positive 8 to 14 days after the second vaccination
- 7 tested positive 15 or more days after the second vaccination
- The case positivity rate for workers 2 weeks after vaccination was 0.05%
They concluded: “The rarity of positive test results 14 days after administration of the second dose of vaccine is encouraging and suggests that the efficacy of these vaccines is maintained outside the trial setting”
A second letter to the editor titled Early Evidence of the Effect of SARS-CoV-2 Vaccine at One Medical Center also appeared in the NEJM. It details the experience of the University of Texas Southwestern Medical Center (UTSW) after vaccinating its healthcare workers. Between December 15, 2020, and January 28, 2021:
- 23,234 employees were vaccinated
- 234 of 8969 nonvaccinated employees (2.6%) became infected
- 112 of 6144 partially vaccinated employees (1.8%) became infected.
- 4 of 8121 fully vaccinated employees (0.05%) became infected
This study similarly concluded: “Real-world experience with SARS-CoV-2 vaccination at UTSW has shown a marked reduction in the incidence of infections among employees. This decrease has preserved the workforce when it was most needed.”
Both letters present very positive news regarding the efficacy of the vaccines at times of maximal community transmission and very higher exposure rates for front line workers. They both show very low post vaccination rates of 0.05%.
Drug manufacturer Regeneron announced that its antibody combination drug REGEN-COV (casirivimab with imdevimab) was 70% effective in a phase 3 trial of three different doses: 8000 mg, 2400 mg, and 1200 mg. The drug received FDA emergency authorization at the 2400 mg dose in November, 2020. Regeneron states it is submitting its new phase 3 results to the FDA to get approval for marketing a lower 1200mg dose of the drug in hopes of increasing availability.
Meanwhile, a separate study, pre-publication in the journal Cell, examined the ability of casirivimab (one of Regeneron’s antibody medicaitons), bamlanivimab (a Lilly antibody medication) and the Pfizer vaccine to protect against the B1351 (South Africa) variant and the P1 (Brazil) variant. It found:
- Both variants were partially resistant to casirivimab (Regeneron)
- Both variants were fully resistant to bamlanivimab (Lilly)
- Both variants were “less efficiently inhibited” by convalescent plasma or antibodies from those vaccinated with the Pfizer vaccine
This study, though small and focused on lab testing only, suggests limitations to antibody treatments and vaccines specifically against the B1351 (South Africa) and P1 (Brazil) variants.
8) U.S. Media Prone To Negative COVID Reporting
An interesting study from Dartmouth College examined U.S. and international media reporting during the COVID pandemic and noted significant negative trends in the U.S. media reporting of COVID-19 related topics. Their conclusions included:
- Overall, we find that relative to other media sources, the most influential U.S. news sources are outliers in terms of the negative tone of their coronavirus stories and their choices of stories covered. We are unable to explain these patterns using differential political views of their audiences or time patterns in infection rates.
- U.S. major outlets do demonstrate an above average interest in promoting prosocial behavior like mask wearing and social distancing.
- Our results suggest that U.S. major outlets publish unusually negative COVID-19 stories in response to reader demand and interest.
They conclude: The U.S. versus non-U.S. difference in negativity among major media outlets may stem from the lack of a major publicly owned player in the U.S. media or the absence of fair and balanced reporting regulations.
One of the most negative outlets named in the report was the NYTimes, which did a good job covering the report’s findings and discussing them with its readers, here.
9) COVID vs Influenza
We modeled mortality rates from COVID compared to prior Influenza seasons in May, 2020. That visual was published in ACEP Now and ultimately adopted by the CDC. This past week, a study was published in the Journal of General Internal Medicine examining a large Boston teaching hospital’s experience with COVID-19 compared to it’s own 8 prior seasons of influenza. The findings were striking.
- 1052 influenza patients and 582 COVID patients were compared.
- In an 8 month season, influenza resulted in an average of 210 hospital admissions while in a 2 month period, COVID resulted in an average 582 hospital admissions.
- Influenza caused a median of 1 patient per week to require a ventilator while COVID caused 17 people a week to require a ventilator.
- 25% of those on ventilators due to influenza had multiple other medical problems vs 4% of COVID patients
- Influenza morality was 3% for admitted patients vs 20% for COVID
They concluded that COVID-19 resulted in more hospitalizations, more severe illness (morbidity), and more deaths (mortality), even in those who were previously healthy. This is no surprise to anyone who has been following the pandemic hospitalizations and deaths across the globe for the past year and serves as yet another reminder that COVID-19 is far worse than the seasonal flu.
10) COVID Variants
The CDC continues to track variant activity in the U.S.. All 50 states have reported B117 (UK) variant cases. 27 states have had cases of the B1351 (South Africa) variant. 18 states have isolated P1 (Brazil) variant. The variants are present in the U.S. and numbers are increasing. This is a good reason for all adults, who have no contraindication, to be vaccinated against COVID-19.