SARS-CoV-2/COVID-19 Toolbox

CDC released updated recommendations for how people can protect themselves and their communities from respiratory viruses, including COVID-19. The new guidance brings a unified approach to addressing risks from a range of common respiratory viral illnesses, such as COVID-19, flu, and RSV.

May 11, 2023, marked the end of the federal COVID-19 public health emergency (PHE) declaration. This doesn’t mean that COVID-19 is over, but the end of the PHE did initiate a cascade of updates to COVID-19 data collection, reporting, and surveillance. Some surveillance metrics will remain the same, but some will change in terms of reporting frequency, data sources, or availability.

This weekly series provides brief summaries of new COVID-19-related studies on many topics, including epidemiology, clinical treatment and management, laboratory science, and modeling.

Emerging Infectious Diseases journal created this spotlight to make it easier for readers to locate articles about coronavirus disease 2019 (COVID-19) as well as other coronavirus diseases in both humans and animals.

MMWR Weekly COVID-19 Briefing is a weekly podcast to update readers on the latest scientific information from CDC’s COVID-19 response. In each episode, MMWR’s Editor-in-Chief, Dr. Charlotte Kent provides an overview of the latest scientific information published in MMWR. New episodes are posted every Monday.

Find maps and charts tracking cases, deaths, and trends of COVID-19 in the United States, updated daily by 8 pm ET

The US CDC COVID-19 page provides current information on routes of transmission, symptoms, preventive measures, treatment, vaccines

Smith DJ, Lambrou A, Patel P
After anti-viral treatment, no consistent association between treatment and rebound was identified.

Cheng L, Dhiyebi H, Varia M, Atanas K, Srikanthan N, Hayat S, et al..
At the peak of the Omicron BA.2 outbreak in April 2022, reported COVID-19 cases were underestimated 19-fold because of changes in clinical testing.

Moulia DL, Wallace M, Roper LE, et al.
Updated vaccine recommendations for children > 6 months and adults >65.

Hause AM, Marquez P, Zhang B, et al.

Scobie HM, Panaggio M, Binder AM, et al.
Surveillance data from October 1, 2020–March 22, 2023

Silk BJ, Scobie HM, Duck WM, et al.
The authors indicate the following: “Changes to the national COVID-19 monitoring strategy and COVID Data Tracker capitalize on marked improvements in multiple surveillance systems.”

DeCuir J, Surie D, Zhu Y, et al.

Mark-Carew M, Kang G, Pampati S, Mead KR, Martin SB Jr., Barrios LC
To reduce school transmission of SARS-CoV-2, K–12 public school districts implemented various types of ventilation improvements.

Morfino RC, Bart SM, Franklin A, et al.
Summary from publication: During August 1–September 9, 2022, the biotech company Ginkgo Bioworks, in collaboration with CDC, evaluated the feasibility of SARS-CoV-2 variant detection in aircraft wastewater from incoming international flights.

Johnson AG, Linde L, Ali AR, et al.

Link-Gelles R, Ciesla AA, Roper LE, et al.

Wong MK, Brooks DJ, Ikejezie J, et al.
COVID-19–associated mortality among persons aged ≥60 years exceeded 80% of total COVID-19 mortality in 2020 and 2021 across all income groups.

Surie D, DeCuir J, Zhu Y, et al.

Link-Gelles R, Ciesla AA, Fleming-Dutra KE, et al.

Melgar M, Lee EH, Miller AD, et al.

Shah MM, Joyce B, Plumb ID, et al.

Link-Gelles R, Ciesla AA, Fleming-Dutra KE, et al.

Hause AM, Marquez P, Zhang B, et al.
Early safety findings from v-safe and the Vaccine Adverse Event Reporting System for bivalent booster doses administered to persons aged ≥12 years during the first 7 weeks of vaccine availability are similar to those previously described for monovalent vaccine booster vaccines.

Clarke KE, Jones JM, Deng Y, et al.

Shi DS, Whitaker M, Marks KJ, et al.

Plumb ID, Feldstein LR, Barkley E, et al.

Ferdinands JM, Rao S, Dixon BE, et al.

Klein NP, Stockwell MS, Demarco M, et al.
Two doses protect against COVID-19–associated emergency department and urgent care encounters among children and adolescents. However, vaccine effectiveness (VE) was lower during Omicron predominance and decreased with time since vaccination; a booster dose restored VE to 81% among adolescents aged 16–17 years. Overall, 2-dose VE against COVID-19–associated hospitalization was 73%–94%.

Halasa NB, Olson SM, Staat MA, et al.
Completion of a 2-dose mRNA COVID-19 vaccination series during pregnancy might help prevent COVID-19 hospitalization among infants aged <6 months.

Danza P, Koo TH, Haddix M, et al.

Omicron summary relative to infection and hospitalization of adults.

Lipkind HS, Vazquez-Benitez G, DeSilva M, et al.

In a retrospective cohort of >40,000 pregnant women, COVID-19 vaccination during pregnancy was not associated with preterm birth or small-for-gestational-age at birth overall, stratified by trimester of vaccination, or number of vaccine doses received during pregnancy, compared with unvaccinated pregnant women.

Fox-Lewis A, Williamson F, Harrower J, Ren X, Sonder GJB, McNeill A, et al.

Xu S, Huang R, Sy LS, et al.

Olson SM, Newhams MM, Halasa NB, et al.

Olson SM, Newhams MM, Halasa NB, et al.

Hause AM, Baggs J, Gee J, et al.

Budzyn SE, Panaggio MJ, Parks SE, et al.

Van Naarden Braun K, Drexler M, Rozenfeld RA, et al.

Hause AM, Gee J, Baggs J, et al.

Brown CM, Vostok J, Johnson H, et al.

Lee JT, Althomsons SP, Wu H, et al.

Christie A, Brooks JT, Hicks LA, et al.

Lindsley WG, Derk RC, Coyle JP, et al.
A combination of HEPA air cleaners and universal masking reduced exposure by up to 90%.

Bryant-Genevier J, Rao CY, Lopes-Cardozo B, et al.

MacNeil JR, Su JR, Broder KR, et al.

Feder KA, Pearlowitz M, Goode A, et al.

Based on laboratory modeling of exposure to SARS-CoV-2 on single-aisle and twin-aisle aircraft, exposures in scenarios in which the middle seat was vacant were reduced by 23% to 57%, compared with full aircraft occupancy, depending upon the model.

Thompson MG, Burgess JL, Naleway AL, et al.
These findings indicate that authorized mRNA COVID-19 vaccines are effective for preventing SARS-CoV-2 infection, regardless of symptom status, among working-age adults in real-world conditions. 

Emerging Infectious Diseases journal created this spotlight to make it easier for readers to locate articles about coronavirus disease 2019 (COVID-19) as well as other coronavirus diseases in both humans and animals.

Provides updated guidance for Point-of-Care testing for SARS-CoV-2.

Pray IW, Ford L, Cole D, et al.

Barrios LC, Riggs MA, Green RF, et al.

Jensen P, Lambert L, et al.

Gharpure R, Hunter CM, Schnall AH, et al.

Report on Safe Household Cleaning and Disinfection for COVID-19 Prevention in the U.S.

Kratzel A, Todt D, V’kovski P, et al.

Lu J, Gu J, Li K, et al.

Gold JA, Gettings JR, Kimball A, et al.

Gee J, Marquez P, Su J, et al.

Firestone MJ, Lorentz AJ, Wang X, et al.

Groves LM, Usagawa L, Elm J, et al.
Twenty-one COVID-19 cases were linked to an index case in a fitness instructor, who, along with a patient who was also an instructor, taught classes <1 day, 1 to <2 days, and ≥2 days before symptom onset; aggregate attack rates were 95%, 13%, and 0%, respectively.

The federal COVID-19 PHE declaration ended on May 11, 2023.

Scobie HM, Panaggio M, Binder AM, et al.
Surveillance data from October 1, 2020–March 22, 2023

Silk BJ, Scobie HM, Duck WM, et al.
The authors indicate the following: “Changes to the national COVID-19 monitoring strategy and COVID Data Tracker capitalize on marked improvements in multiple surveillance systems.”

Forecasts of disease burden help inform public health decision making by projecting the likely impact of COVID-19 in the next few weeks.

As some communities in the United States begin to plan and hold events and gatherings, the CDC offers the following considerations for enhancing protection of individuals and communities and preventing spread of coronavirus disease 2019

As of 12:01AM ET on June 12, 2022, all air passengers, regardless of citizenship or vaccination status, are no longer required to show a negative viral COVID-19 test result, or documentation of recovery from COVID-19, before boarding a flight to the United States.

Based on laboratory modeling of exposure to SARS-CoV-2 on single-aisle and twin-aisle aircraft, exposures in scenarios in which the middle seat was vacant were reduced by 23% to 57%, compared with full aircraft occupancy, depending upon the model.

Recommendations/requirements for international travel (masks, testing, quarantine) for vaccinated and unvaccinated Americans.

This page is about travel that is different from your everyday activities, away from your local community.

Find guidance and resources on preventing and controlling COVID-19 infections in globally mobile populations.

Public Health Communication at US Ports of Entry

Find maps and charts tracking cases, deaths, and trends of COVID-19 in the United States, updated daily by 8 pm ET

CDC is committed to helping cruise lines provide for the safety and well-being of their crew members while onboard cruise ships and as they disembark. CDC is allowing crew members to disembark from all cruise ships in U.S. waters with certain precautions.

This page is about travel that is different from your everyday activities, away from your local community.

This document provides guidance for ships originating from or porting in the United States to help prevent, detect, report, and medically manage suspected or confirmed COVID-19 cases. As ships travel worldwide, ship management and medical staff need to be aware of and respond to local jurisdictional requirements.

For maritime pilots, potential sources of exposures include close contact with a vessel crewmember with COVID-19 and touching your nose, mouth, or eyes after contacting surfaces or handling items that a person with COVID-19 has touched.

Guidance, fact sheets, and tools for many industries and occupations

Updated guidance related to K-12 schools and transmission of SARS-CoV-2- recommendation that “3 feet between students in classrooms could provide a feasible definition of physical distancing so long as other prevention measures are maximized.

Plan, Prepare, and Respond

Plan, Prepare, and Respond

For maritime pilots, potential sources of exposures include close contact with a vessel crewmember with COVID-19 and touching your nose, mouth, or eyes after contacting surfaces or handling items that a person with COVID-19 has touched.

Hause AM, Marquez P, Zhang B, et al.

Melgar M, Lee EH, Miller AD, et al.

Shi DS, Whitaker M, Marks KJ, et al.

CDC released updated recommendations for how people can protect themselves and their communities from respiratory viruses, including COVID-19. The new guidance brings a unified approach to addressing risks from a range of common respiratory viral illnesses, such as COVID-19, flu, and RSV.

Additional info for the immunocompromised: Know how to protect yourself and what to do if you get sick.

Tools, information, and action steps to share with your family, friends, and healthcare provider

CDC is launching a new tool to monitor COVID-19 Community Levels. Each county’s COVID-19 Community Level is ranked as low, medium, or high. The community level, updated regularly, will be tied to high, medium or low precautions based on certain factors such as hospitalizations, cases and beds filled.

Good ventilation, along with other preventive actions, like staying 6 feet apart and correctly wearing masks, can help prevent you from getting and spreading COVID-19.

Current advice for visiting a restaurant, bar, nail salon, the library, traveling overnight, hosting a cook-out, etc.

Added three new Frequently Asked Questions (FAQs) on the usefulness of carbon dioxide monitors to inform ventilation decisions, the useful of temperature and relative humidity to control the spread of COVID-19, and the use of fans indoors.

Information for Where You Live, Work, Learn, and Play

CDC offers supplemental information about attending sporting events, as some communities begin to open up.

As some communities in the United States begin to plan and hold events and gatherings, the CDC offers the following considerations for enhancing protection of individuals and communities and preventing spread of coronavirus disease 2019

Resources and tools to help pregnant people, breastfeeding people and new parents caring for infants to protect their health and help people who serve these communities communicate with them.

Groves LM, Usagawa L, Elm J, et al.
Twenty-one COVID-19 cases were linked to an index case in a fitness instructor, who, along with a patient who was also an instructor, taught classes <1 day, 1 to <2 days, and ≥2 days before symptom onset; aggregate attack rates were 95%, 13%, and 0%, respectively.

Interim Infection Prevention and Control Guidance for Dental Settings During the Coronavirus Disease 2019 (COVID-19) Pandemic

Resources for people who work and reside in prisons, jails, and detention centers.

Guidance and tools to help administrators of correctional and detention facilities make decisions and protect and communicate with staff, people who are incarcerated, and their communities.

This guidance applies to all U.S. settings where healthcare is delivered, including nursing homes and home health. The recommendations in this guidance continue to apply after the expiration of the federal COVID-19 Public Health Emergency.

In general, asymptomatic healthcare personnel (HCP) who have had a higher-risk exposure do not require work restriction, regardless of vaccination status, if they do not develop symptoms or test positive for SARS-CoV-2.

Due to the increased transmissibility of the Omicron variant and concerns about potential impacts on the healthcare system, the CDC is updating recommendations to enhance protection for healthcare personnel, patients, and visitors, and ensure adequate staffing in healthcare facilities.

Bryant-Genevier J, Rao CY, Lopes-Cardozo B, et al.

Tools to support Health Departments’ contact tracing.

During this COCA Call, presenters will discuss the current impact of the COVID-19 pandemic on healthcare systems in the U.S., including key successes and challenges from the hospital response perspective.

CDC’s Prepare to Care for COVID-19 is a resource with practical tools clinicians can use to care for patients with COVID-19, and will be regularly updated to help clinicians adapt as the outbreak unfolds.

Added guidance on offering and promoting COVID-19 vaccination, prevention strategies for IHEs where everyone is fully vaccinated and for IHEs where not everyone is fully vaccinated, general guidance.

Mark-Carew M, Kang G, Pampati S, Mead KR, Martin SB Jr., Barrios LC
To reduce school transmission of SARS-CoV-2, K–12 public school districts implemented various types of ventilation improvements.

Budzyn SE, Panaggio MJ, Parks SE, et al.

Lu J, Gu J, Li K, et al.

Guidance for minimizing spread of disease in restaurants and bars.

Wong MK, Brooks DJ, Ikejezie J, et al.
COVID-19–associated mortality among persons aged ≥60 years exceeded 80% of total COVID-19 mortality in 2020 and 2021 across all income groups.

Lee JT, Althomsons SP, Wu H, et al.

This guidance has been updated and organized according to IPC practices that should remain in place whether or not nursing homes are experiencing outbreaks of SARS-CoV-2. 

Interim SARS-CoV-2 Testing Guidelines for Nursing Home Residents and Healthcare Personnel

Considerations for Use in Nursing Homes and other Long-Term Care Facilities

The Respiratory Surveillance Line List provides a template for data collection and active monitoring of both residents and staff during a suspected respiratory illness cluster or outbreak at a nursing home or other LTC facility. Using this tool will provide facilities with a line listing of all individuals monitored for or meeting the case definition for the outbreak illness.

Van Naarden Braun K, Drexler M, Rozenfeld RA, et al.

Key Points include strategies for contingency capacity

Data were added from studies published since the last update that further demonstrate that mask wearing reduces new infections. Data were added that demonstrate the importance of mask fit to improve performance and reduce community exposure to SARS-CoV-2. A section was added on the health effects of mask wearing

Barrios LC, Riggs MA, Green RF, et al.

Dr. Brooks provided a brief update on the COVID response at CDC, and some of the latest scientific developments and guidance. Dr. Michael Bell reviewed CDC’s latest considerations for wearing cloth face coverings and understanding the importance of cloth face coverings and wearing them properly.

How to Select, Wear, and Clean Your Mask

Key Points include strategies for contingency capacity

Currently there remains a lack of regulatory alignment among OSHA, the Food and Drug Administration (FDA), and the National Institute for Occupational Safety and Health (NIOSH) regarding respirator approval for use in health care.

Jensen P, Lambert L, et al.

Includes downloadable documents

Gharpure R, Hunter CM, Schnall AH, et al.

Report on Safe Household Cleaning and Disinfection for COVID-19 Prevention in the U.S.

Dr. Brooks provided a brief update on the COVID response at CDC, and some of the latest scientific developments and guidance. Dr. Michael Bell reviewed CDC’s latest considerations for wearing cloth face coverings and understanding the importance of cloth face coverings and wearing them properly.

This guidance is intended for clinical laboratory and support staff who handle or process specimens associated with COVID-19.

Quick reference guide adapted from the CDC Laboratory Training course for shipping Covid samples.

This site includes updated information on importing SARS-CoV-2 isolates, cultures or fluids reasonably expected to contain SARS-CoV-2.

Includes a FAQs on import permits in the US, including questions about SARS-CoV-2

Kratzel A, Todt D, V’kovski P, et al.

Danza P, Koo TH, Haddix M, et al.

Omicron summary relative to infection and hospitalization of adults.

Updated information on the Omicron variant

Due to the increased transmissibility of the Omicron variant and concerns about potential impacts on the healthcare system, the CDC is updating recommendations to enhance protection for healthcare personnel, patients, and visitors, and ensure adequate staffing in healthcare facilities.

provides information on the Delta variant and what you can do to help slow the spread

Maps and a list of countries that have reported variants of SARS-CoV-2.

More in depth information for laboratories testing for Covid-19 variants.

Firestone MJ, Lorentz AJ, Wang X, et al.

Mark-Carew M, Kang G, Pampati S, Mead KR, Martin SB Jr., Barrios LC
To reduce school transmission of SARS-CoV-2, K–12 public school districts implemented various types of ventilation improvements.

Clarke KE, Jones JM, Deng Y, et al.

Fox-Lewis A, Williamson F, Harrower J, Ren X, Sonder GJB, McNeill A, et al.

Comparison between isolation and quarantine in the context of COVID-19 vaccination

Brown CM, Vostok J, Johnson H, et al.

Christie A, Brooks JT, Hicks LA, et al.

This page includes multiple examples of outdoor activites and the risk for unvaccinated individual wearing the covering by unvaccinated

It is possible for people to be infected through contact with contaminated surfaces or objects (fomites), but the risk is generally considered to be low.

This science brief has been updated to reflect current knowledge about SARS-CoV-2 transmission and reformatted to be more concise.

Feder KA, Pearlowitz M, Goode A, et al.

Jensen P, Lambert L, et al.

Gold JA, Gettings JR, Kimball A, et al.

Groves LM, Usagawa L, Elm J, et al.
Twenty-one COVID-19 cases were linked to an index case in a fitness instructor, who, along with a patient who was also an instructor, taught classes <1 day, 1 to <2 days, and ≥2 days before symptom onset; aggregate attack rates were 95%, 13%, and 0%, respectively.

CDC is tracking a new SARS-CoV-2 variant called BA.2.86 (Pirola) and working to better understand its potential impact on public health.

Discusses the risk of animals spreading Covid and the risk of spreading Covid to animals, also research with animals.

Tools and resources for occupational safety and health professionals and state and local public health officials assessing manufacturing facilities

Cheng L, Dhiyebi H, Varia M, Atanas K, Srikanthan N, Hayat S, et al..
At the peak of the Omicron BA.2 outbreak in April 2022, reported COVID-19 cases were underestimated 19-fold because of changes in clinical testing.

Includes information on various tests, who can use, and extended expiration dating for some tests.

Link-Gelles R, Ciesla AA, Fleming-Dutra KE, et al.

A new way to get tested for Covid and treated at the same site, if appropriate. People who test positive at home can also bring those tests to the sites to be evaluated for treatment.

Use this guidance to help make sure you reduce those risks as much as possible to keep you and your coworkers, patients, customers, family, and community safe and healthy while you perform POC tests.

Lindsley WG, Derk RC, Coyle JP, et al.
A combination of HEPA air cleaners and universal masking reduced exposure by up to 90%.

Gettings J, Czarnik M, Morris E, et al.

CDC is offering a series of brief (15-20 minute) webinars addressing topics around COVID-19 vaccination.

Added three new Frequently Asked Questions (FAQs) on the usefulness of carbon dioxide monitors to inform ventilation decisions, the useful of temperature and relative humidity to control the spread of COVID-19, and the use of fans indoors.

Lu J, Gu J, Li K, et al.

Key Points include strategies for contingency capacity

This site provides a listing of NIOSH-approved particulate filtering facepiece respirators. This type of air-purifying respirators protects by filtering particles out of the air the user is breathing. There are seven classes of filters for NIOSH-approved filtering facepiece respirators available at this time. Ninety-five percent is the minimal level of filtration that will be approved by NIOSH. The N, R, and P designations refer to the filter’s oil resistance as described below.

Public Health Communication at US Ports of Entry

Keck JW, Adatorwovor R, Liversedge M, et al.
Persons living in long-term care facilities (LTCFs) were disproportionately affected by COVID-19. We used wastewater surveillance to detect SARS-CoV-2 infection in this setting by collecting and testing 24-hour composite wastewater samples 2–4 times weekly at 6 LTCFs in Kentucky, USA, during March 2021–February 2022.

CDC’s new page has county-level information on how Flu, COVID-19 and RSV viruses are trending in your area, and other useful info.

Quick reference guide adapted from the CDC Laboratory Training course for shipping Covid samples.

CDC’s National Wastewater Surveillance System (NWSS) program collects and displays wastewater data from communities across the United States.

Morfino RC, Bart SM, Franklin A, et al.
Summary from publication: During August 1–September 9, 2022, the biotech company Ginkgo Bioworks, in collaboration with CDC, evaluated the feasibility of SARS-CoV-2 variant detection in aircraft wastewater from incoming international flights.

A new public health tool to understand COVID-19 spread in a community

Good ventilation, along with other preventive actions, like staying 6 feet apart and correctly wearing masks, can help prevent you from getting and spreading COVID-19.

Plan, Prepare, and Respond

Information for Where You Live, Work, Learn, and Play

Tools and resources for occupational safety and health professionals and state and local public health officials assessing manufacturing facilities

This section provides steps and consideration that jurisdictions can use to develop a protocol for the tracing of close contacts.

Tools to support Health Departments’ contact tracing.