Adapt the frequency of COVID-19 testing depending on transmission rate
and community immunity, study finds

Date:
January 18, 2022
Source:
University of Texas at Austin
Summary:
Expanding rapid testing stands out as an affordable way to
help mitigate risks associated with COVID-19 and emerging
variants. Infectious disease researchers have developed a new
model that tailors testing recommendations to new variants and
likely immunity levels in a community, offering a new strategy
as public health leaders seek a way out of a pandemic that has so
far thwarted the best efforts to end its spread.



FULL STORY ========================================================================== Expanding rapid testing stands out as an affordable way to help mitigate
risks associated with COVID-19 and emerging variants. Infectious disease researchers at The University of Texas at Austin have developed a new
model that tailors testing recommendations to new variants and likely
immunity levels in a community, offering a new strategy as public health leaders seek a way out of a pandemic that has so far thwarted the best
efforts to end its spread. It is the first study to identify optimal
levels of testing in a partially immunized population.


========================================================================== Analysis from the UT Covid-19 Modeling Consortium, published in The Lancet Regional Health -- Americas, describes cost-effective testing for people without symptoms and recommends isolation strategies to help policymakers safeguard against COVID-19 resurgences linked to new variants. A prior
study from the team published in TheLancet Public Health provided optimal testing strategies for a fully unvaccinated population.

"As COVID-19 continues to evolve and cause waves of infections worldwide,
rapid testing is an economic strategy for slowing spread and saving
lives. Our study helps decision makers determine whether and how often
to test," said Lauren Ancel Meyers, director of the consortium and a
professor of integrative biology and statistics and data sciences at UT
Austin. "Frequent testing is recommended when the virus is spreading
rapidly in a population with low levels of immunity." The consortium
developed a multiscale model that uses how much the virus is circulating
in a local population, how much of the population is immunized against COVID-19, and other factors to determine how often people without symptoms should be tested in order to help reduce the spread of the virus.

The study recommends a staged strategy that tracks the changing risks as
new variants emerge and subside. If a rapidly spreading variant emerges
in a partially immunized population, the researchers recommend testing
everyone at least once per week combined with a 10-day isolation of
people who test positive and their households. As the level of immunity increases in a population, testing can be rolled back to once per month
and eventually suspended. For example, for a variant as infectious and immune-evasive as omicron, daily testing is advised until 70% of the
population is immunized against the variant, followed by monthly testing
until 80% are immunized.

The U.S. may face future waves of transmission caused by vaccine-evasive variants. The study suggests that proactive testing will remain a cost- effective strategy for reducing risks and avoiding burdensome restrictions
as new threats arise. The recommended testing strategies balance the costs associated with administering tests and missing school or work during
isolation with the benefits of preventing COVID-19 hospitalizations
and deaths.

"As COVID-19 continues to evolve, so does our arsenal of effective countermeasures. Our research shows that mass use of rapid tests
coupled with voluntary isolation and household quarantine can be
both life saving and cost saving, if tailored to local risks," Meyers
said. "Now is the time to prepare for yet unknown COVID-19 variants and
future pandemics. Proactive testing and isolation can be key to keeping
schools and businesses open while preventing overwhelming surges in
our hospitals." Co-corresponding authors are Zhanwei Du, previously
of Meyer's lab, Yan Bai of The University of Hong Kong and Lin Wang
of the University of Cambridge. Other authors are Xutong Wang of The
University of Texas at Austin; Abhishek Pandey, Meagan Fitzpatrick and
Alison P. Galvani of Yale School of Public Health; Matteo Chinazzi, Ana
Pastore y Piontti and Alessandro Vespignani of Northeastern University; Nathaniel Hupert of Weill Cornell Medicine and Cornell Institute
for Disease and Disaster Preparedness; Michael Lachmann of Santa Fe
Institute; and Benjamin J. Cowling of Hong Kong University. Meyers is
the Cooley Centennial Professor of Integrative Biology and Statistics &
Data Sciences at The University of Texas at Austin.

The research was supported by the National Institutes of Health,
Centers for Disease Control and Prevention, HK Innovation and Technology Commission, China National Natural Science Foundation, European Research Council and EPSRC Impact Acceleration Grant.

special promotion Explore the latest scientific research on sleep and
dreams in this free online course from New Scientist -- Sign_up_now_>>> academy.newscientist.com/courses/science-of-sleep-and-dreams ========================================================================== Story Source: Materials provided by University_of_Texas_at_Austin. Note: Content may be edited for style and length.


========================================================================== Journal References:
1. Zhanwei Du, Lin Wang, Yuan Bai, Xutong Wang, Abhishek Pandey,
Meagan C.

Fitzpatrick, Matteo Chinazzi, Ana Pastore y Piontti, Nathaniel
Hupert, Michael Lachmann, Alessandro Vespignani, Alison P. Galvani,
Benjamin J.

Cowling, Lauren Ancel Meyers. Cost-effective proactive testing
strategies during COVID-19 mass vaccination: A modelling
study. The Lancet Regional Health - Americas, 2022; 8: 100182 DOI:
10.1016/j.lana.2021.100182
2. Zhanwei Du, Abhishek Pandey, Yuan Bai, Meagan C Fitzpatrick, Matteo
Chinazzi, Ana Pastore y Piontti, Michael Lachmann, Alessandro
Vespignani, Benjamin J Cowling, Alison P Galvani, Lauren Ancel
Meyers. Comparative cost-effectiveness of SARS-CoV-2 testing
strategies in the USA: a modelling study. The Lancet Public Health,
2021; 6 (3): e184 DOI: 10.1016/S2468-2667(21)00002-5 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2022/01/220118125144.htm

--- up 6 weeks, 3 days, 7 hours, 13 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)