COVID-19 prevention strategies
Monitoring community levels of COVID-19 to guide COVID-19 prevention efforts. People can use information about the current level of impact of COVID-19 in their community to decide which preventive behaviors to use and when (anytime or at specific times), based on their risk of severe illness and the of their family members. , their risk tolerance and specific determining factors. CDC’s community tiers for COVID-19 reflect the current effect of COVID-19 on communities and identify geographic areas that may experience increased severe outcomes associated with COVID-19, based on hospitalization rates, occupancy hospital beds and the incidence of COVID-19 during previous years. period*** (1). Prevention recommendations based on community levels of COVID-19 have clear goals to reduce medically significant illness and limit the burden on the health care system. At all levels of the COVID-19 community (low, medium, and high), recommendations emphasize staying up-to-date with vaccination, improving ventilation, testing symptomatic and exposed persons, and isolating those with infected. At the average level of the COVID-19 community, recommended strategies include increasing protections for persons who are at high risk for severe disease (eg, use of masks or respirators that provide a higher level of protection for the wearer) . At the high level of the COVID-19 community, additional recommendations focus on all persons wearing masks indoors in public and further increasing protection for high-risk populations.††† As SARS-CoV-2 continues to circulate, changes in the Community Levels of COVID-19 for a jurisdiction help signal when the use of certain prevention strategies should be discontinued or increased, based on a person’s level of risk for severe disease or of their family. or social contacts. The Community Levels of COVID-19 provide a broad framework for public health officials and jurisdictions to use and adapt as needed based on local context by combining local information to assess the need for public health interventions.
Non-pharmaceutical interventions. Implementation of multiple prevention strategies helps protect individuals and communities from exposure to SARS-CoV-2 and reduces the risk of significant medical illness and death by reducing the risk of infection (Table). Implementation of multiple non-pharmaceutical preventive interventions can complement the use of vaccines and therapies, particularly as community rates of COVID-19 increase and among persons at high risk for severe disease. The CDC’s recommendations for preventing COVID-19 no longer differentiate based on a person’s vaccination status because new infections do occur, although they are generally mild (16), and people who have had COVID-19 but have not been vaccinated have some protection against severe disease from their previous infection (17). In addition to recommended strategies at all levels of the COVID-19 community, education and messaging to help individuals understand their risk for medically significant illness complement recommendations for risk-based prevention strategies.
Testing for current infection. Diagnostic testing can identify infections early so that infected persons can take action to reduce the risk of transmission of the virus and receive treatment, if clinically indicated, to reduce their risk of serious illness and death. All persons should seek testing for active infection when they are symptomatic or have a known or suspected exposure to someone with COVID-19. When considering whether and where to implement screening testing of asymptomatic persons with no known exposure, public health officials may consider prioritizing high-risk collection settings, such as long-term care facilities, shelters for homelessness and correctional facilities and workplace settings that include congregate housing with limited access to medical care.§§§ In these types of high-risk clustered settings, screening testing can complement diagnostic testing of symptomatic persons by identifying asymptomatic infected persons (18,19). When implemented, screening testing strategies should include all persons, regardless of vaccination status. Screening testing may not be cost-effective in general community settings, particularly if the prevalence of COVID-19 is low (20,21).
Isolation. Symptomatic or infected persons should be isolated immediately, and infected persons should remain in isolation for ≥5 days and wear an appropriate, high-quality mask or respirator if they must be around others. Infected persons may end isolation after 5 days only when they have been fever-free for ≥24 hours without the use of medications and all other symptoms have improved, and they should continue to wear a mask or respirator around others in at home and in public. day 10¶¶¶ (Figure) (22,23). Persons who have access to antigen tests and who choose to use testing to determine when they can stop unmasking should wait to do the first test until at least day 6 and they have been fever-free for ≥24 hours without the use of fever-reducing medications. and all other symptoms improved. Using two antigen tests with ≥48 hours between tests provides more reliable information due to improved test sensitivity (24). Two consecutive test results must be negative for persons to discontinue masking. If each test result is positive, persons should continue to wear a mask around others and continue testing every 48 hours until they have two consecutive negative results.****
Management of exposures to SARS-CoV-2. CDC now recommends case investigation and contact tracing only in healthcare settings and certain high-risk congregate settings.†††† In all other circumstances, public health efforts may focus on case notification and providing exposed persons with information and resources to access testing. Persons who have had confirmed or suspected recent exposure to an infected person should wear a mask for 10 days around others when in public and should be tested ≥5 days after exposure (or sooner if symptomatic), regardless of their vaccination status. .§§§§ In light of the high population levels of anti-SARS-CoV-2 seroprevalence (7,16), and to limit social and economic impacts, quarantine of exposed persons is no longer recommended, regardless of vaccination status.