Global COVID-19 infection rates may be higher than previously reported
Study suggests two-thirds of the global population may have antibodies from vaccination or infection
Peer-Reviewed PublicationIMAGE: A PHLEBOTOMIST COLLECTS BLOOD IN THE HAY FIELD IN THE SELENGE AIMAG (PROVINCE) IN MONGOLIA FOR THE THIRD ROUND OF THE SARS-COV-2 POPULATION-BASED SEROEPIDEMIOLOGIC INVESTIGATION IN MAY 2021. view more
CREDIT: MONGOLIAN SARS-COV-2 POPULATION-BASED SEROEPIDEMIOLOGICAL INVESTIGATION PROJECT TEAM (CC BY 4.0, HTTPS://CREATIVECOMMONS.ORG/LICENSES/BY/4.0/)
Serosurveillance provides estimates of antibody levels against infectious diseases and is considered the gold standard for measuring population immunity due to past infection or vaccination. A study publishing November 10th in the open access journal PLOS Medicine jointly authored by the World Health Organization’s (WHO) Unity Studies and SeroTracker and colleagues suggests that based on seroprevalence, global COVID-19 infection rates are likely to be higher than previously reported.
The global scale of COVID-19 infections is not well understood. Routine surveillance data underestimates infection and cannot infer population immunity due to asymptomatic infections and uneven access to diagnostics. In order to ascertain the true rates of infection and indicators of immunity in the population against SARS-CoV-2 over time, researchers conducted a systematic review and meta-analysis of seroprevalence studies published from January 1, 2020 to May 20, 2022. From their search parameters, the authors identified 965 distinct seroprevalence studies sampling 5,346,069 participants between January 2020 and April 2022, with 43% of these studies being from low-middle income countries. They analyzed seroprevalence by country and month, estimating regional and global seroprevalence over time, and estimated seropositivity rates from infection versus infection or vaccination.
The researchers found that global seroprevalence has risen from 7.7% in June 2020 to 59.2% in September 2021, suggesting two-thirds of the global population may be SARS-CoV-2 seropositive from either vaccination or infection. Estimates of COVID-19 infections based on seroprevalence data far exceed reported cases, suggesting a bigger global impact of COVID-19 than previously known. The study did have limits, such as underrepresentation of some countries in the data, and overrepresentation of others.
According to the authors, “This study on global seroprevalence of SARS-CoV-2 antibodies found that while seroprevalence has increased over time, a third of the global population tested negative for antibodies against the virus as of September 2021 estimates. It was also found that compared to seroprevalence estimates, routine testing for COVID-19 has largely underestimated the number of global infections.”
Bergeri, Whelan, Ware, Subissi and colleagues add, “As we enter the third year of the COVID-19 pandemic, implementation of a global system or network for targeted, multi-pathogen, high-quality and standardized collaborative serosurveillance is a crucial next step to monitor the COVID-19 pandemic and contribute to preparedness for other emerging respiratory pathogens.”
#####
In your coverage, please use this URL to provide access to the freely available paper in PLOS Medicine: http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1004107
Citation: Bergeri I, Whelan M, Ware H, Subissi L, Nardone A, Lewis HC, et al. (2022) Global SARS-CoV-2 seroprevalence from January 2020 to April 2022: A systematic review and meta-analysis of standardized population-based studies. PLoS Med 19(11): e1004107. https://doi.org/10.1371/journal.pmed.1004107
Author Countries: Switzerland, Canada, France, Congo, Egypt, India, Philippines, Denmark, United States, United Kingdom
Funding: see manuscript
JOURNAL
PLoS Medicine
METHOD OF RESEARCH
Observational study
SUBJECT OF RESEARCH
People
COI STATEMENT
Competing Interests: see manuscript
COVID testing programs may increase risky behavior
Frequent, mandatory surveillance testing was one of the techniques deployed in some jurisdictions in an attempt to control COVID-19, but new research shows that such testing may have the unintended consequence of riskier behavior by those enrolled in the testing.
Based on a false sense of security, students who participated in frequent COVID-19 testing at two universities engaged in more behavior known to increase the risk of spreading the virus than they might have otherwise, according to results of surveys led by University of Wyoming economists.
“Recent research provides some evidence that people increase risky behavior in response to facemask wearing and vaccines, but this is the first study to examine the behavioral responses to mandatory testing,” wrote researchers Chian Jones Ritten, Linda Thunstrom and Todd Cherry, of UW, and J.D. Wulfhorst, of the University of Idaho. “Overall, (our) results suggest that students perceived that the mandatory testing policy decreased their risk of contracting COVID-19, and that this perception led to higher participation in COVID-risky events.”
The research findings were published Friday in PNAS Nexus, the open access sister journal of the prestigious Proceedings of the National Academy of Sciences.
During the fall 2020 semester, UW required all on-campus undergraduate students to be tested for COVID twice weekly, while the University of Idaho tested a small random sample of students weekly. Both universities required masks for all indoor events on campus.
The researchers surveyed students at both universities and found that, in both cases, respondents who were tested more frequently perceived that they were at a reduced risk of contracting the virus. Those individuals also more frequently attended “risky” events such as large and small indoor gatherings and frequented restaurants and bars.
From a public health standpoint, such behavior is problematic because inaccurate and delayed test results can result in people who believe they’re not infected carrying the virus and infecting others. Although perhaps unlikely, it is possible that the benefits of testing programs could be entirely offset by increased viral transmission, the researchers say.
While other research shows that, in other contexts, this type of risk compensation behavior is generally small in magnitude, small behavioral changes may lead to meaningful increases in disease spread.
“These unintended consequences may pose a particularly large threat to public health when incubation times are short, the virus is highly transmissible and the risk of false negatives is high, such as with the Omicron variant of the coronavirus,” the researchers wrote.
Interestingly, the surveys found that women, more than men, perceive that increased testing reduces the risk of contracting the virus -- and are, thus, more likely to increase risky behavior than men.
Overall, the research shows that mandatory testing programs should be accompanied by mitigation measures to reduce the unintended consequence of people engaging in riskier behavior, the researchers say.
“Our findings suggest that programs with frequent testing may unintentionally increase behavior known to contribute to virus spread -- the potential consequences of which are amplified by the exponential nature of viral spread,” the researchers concluded. “Thus, when implementing mandatory testing programs to manage a pathogen, it is important to communicate the programs’ limitations in protecting against infection and highlight the potential for unintended behavioral responses.”
JOURNAL
PNAS Nexus
METHOD OF RESEARCH
Survey
SUBJECT OF RESEARCH
People
ARTICLE TITLE
Frequent mandatory COVID-19 testing may increase risky behavior
ARTICLE PUBLICATION DATE
10-Nov-2022
Investigating COVID-19 deaths for children and young people
Study confirms death rates remain low and fatalities are often linked to underlying conditions
Peer-Reviewed PublicationIMAGE: COVID-19 INFECTION RATES BY AGE GROUP AND NUMBER OF DEATHS BY CAUSE OF DEATH IN CYP <20 YEARS (PREDOMINANT CIRCULATING VARIANT SHOWN BY COLOURED CHEVRONS; ERROR BARS INDICATE 95% CONFIDENCE INTERVALS). view more
CREDIT: BERTRAN M, ET AL., 2022, PLOS MEDICINE, CC-BY 4.0 (HTTPS://CREATIVECOMMONS.ORG/LICENSES/BY/4.0/)
A new study conducted in England shows that the risk of death due to COVID-19 remains very low for children and young people, and most deaths occur in those with underlying health conditions. Marta Bertran of the UK Health Security Agency, London, and colleagues present these findings November 8th in the open access journal PLOS Medicine.
Pediatric deaths due to COVID-19 are rare, and because infection tends to be mild in children and young people compared to adults, it can be challenging to assess COVID-19 severity and cause of death for those with serious underlying health conditions. In addition, because death due to COVID-19 is so uncommon for children, limited data exist to examine such fatalities at the population level.
To improve our understanding of pediatric COVID-19 deaths—and which factors might be linked to an increased risk of death—Bertran and colleagues analyzed detailed data on everyone aged less than 20 years in England who died within 100 days of a confirmed COVID-19 infection between March 2020 and December 2021.
The analysis showed that, of 185 total deaths that occurred, 81 were due to COVID-19. Of those who died from COVID-19, 75 percent had underlying health conditions, primarily severe neurodisability and conditions involving a compromised immune system. Half of COVID-19 deaths occurred within seven days of infection and the majority within 30 days of infection.
These findings confirm that death due to COVID-19 remained rare in children and young people even as new variants of the SARS-Cov-2 virus emerged during the study period. They also highlight which children might be at greater risk of COVID-19 death, which could help inform parents, clinicians, and policymakers about prevention through vaccination, for example, and seeking early treatment.
The authors note that this study emphasizes the need for detailed review of individual cases in order to collaboratively monitor rare COVID-19 outcomes in children. They also note that the study period occurred prior to the rise of the Omicron variant, which now dominates cases worldwide.
Coauthor Shamez Ladhani adds, “Our national surveillance in England continues to show a very very low risk of death due to COVID-19 in children and teenagers, with most fatalities occurring in those with multiple and life-limiting underlying conditions.”
#####
In your coverage, please use this URL to provide access to the freely available paper in PLOS Medicine: http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1004118
Citation: Bertran M, Amin-Chowdhury Z, Davies HG, Allen H, Clare T, Davison C, et al. (2022) COVID-19 deaths in children and young people in England, March 2020 to December 2021: An active prospective national surveillance study. PLoS Med 19(11): e1004118. https://doi.org/10.1371/journal.pmed.1004118
Author Countries: United Kingdom
Funding: The author(s) received no specific funding for this work.
JOURNAL
PLoS Medicine
METHOD OF RESEARCH
Observational study
SUBJECT OF RESEARCH
People
No comments:
Post a Comment