Important update: Healthcare facilities
CDC has updated select ways to operate healthcare systems effectively in response to COVID-19 vaccination. Learn more
UPDATE
Given new evidence on the B.1.617.2 (Delta) variant, CDC has updated the guidance for fully vaccinated people. CDC recommends universal indoor masking for all teachers, staff, students, and visitors to K-12 schools, regardless of vaccination status. Children should return to full-time in-person learning in the fall with layered prevention strategies in place.
UPDATE
The White House announced that vaccines will be required for international travelers coming into the United States, with an effective date of November 8, 2021. For purposes of entry into the United States, vaccines accepted will include FDA approved or authorized and WHO Emergency Use Listing vaccines. More information is available here.
UPDATE
Travel requirements to enter the United States are changing, starting November 8, 2021. More information is available here.

Unpacking Variants

Unpacking Variants
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Interpretive Summary for April 22, 2022

Unpacking Variants

Throughout the pandemic, the United States has experienced waves of different variants of SARS-CoV-2, the virus that causes COVID-19. SARS-CoV-2 is constantly changing, and new variants of the virus are expected to occur. In early 2021, the Alpha variant emerged, followed by the Delta variant later that summer. In late 2021 and throughout early 2022, the Omicron variant swept across the country and continues to be the predominant variant circulating in the United States.

In recent weeks, BA.2.12.1, an Omicron sublineage (sometimes called a “subvariant”), has emerged and is increasing in prevalence in parts of the country. Some early evidence suggests BA.2.12.1 is increasing in variant proportion faster than other Omicron sublineages. CDC is working to better understand BA.2.12.1, how it spreads, and how well existing treatments and vaccines for COVID-19 work against it.

As the virus continues to evolve, we expect to see new variants (and their many different lineages and sublineages) emerge and disappear as they compete against each other and other circulating viruses. CDC scientists closely monitor trends in variant proportions and evaluate the public health impact. While new variants may cause increases in cases, especially in localized areas, it is important to remember that we have all the tools needed to prevent COVID-19. CDC’s COVID-19 Community Levels tool can help communities and people make decisions about prevention strategies. Find your COVID-19 Community Level.

Did you know? Variants are made up of multiple lineages (or closely related groups of variants) and sublineages. Each of these variants starts with a parent lineage (for example, BA.1.1.529 for Omicron) followed by descendant lineages, which can all be arranged like a family tree. As the virus spreads, genetic mutations can accumulate and change the characteristics of the virus. Even though most mutations do not affect the characteristics of the virus, genomic surveillance systems detect and track mutations, regardless of whether they pose public health threats. To see variant proportion data, visit COVID Data Tracker.

What's New

COVID-19 Community Levels

On February 25, 2022, CDC updated the way it monitors COVID-19’s impact on our communities. Widespread availability of vaccines and testing, advances in treatments, and increasing levels of immunity in the population through vaccination or previous infection have moved the COVID-19 pandemic to a new phase. While we can’t prevent all cases of COVID-19, we can continue to limit the spread and protect those who are most at risk of severe illness.

Currently, there are 39 (1.21%) counties, districts, or territories with a high COVID-19 Community Level, 231 (7.17%) counties with a medium Community Level, and 2,954 (91.63%) counties with a low Community Level. This represents a slight (0.78%) increase in the number of high-level counties, a small (+1.67%) increase in the number of medium-level counties, and a corresponding (−2.45%) decrease in the number of low-level counties. Twenty-five (44.64%) of 56 jurisdictions had no high- or medium-level counties this week.

To check your COVID-19 community level, visit COVID Data Tracker.

U.S. COVID-19 Community Levels by County

map showing U.S. COVID-19 Community Levels by County 04-22-2022 legend for map green is low yellow is medium orange is high grey is no data

Reported Cases

As of April 20, 2022, the current 7-day moving average of daily new cases (42,605) increased 35.3% compared with the previous 7-day moving average (31,495). A total of 80,648,481 COVID-19 cases have been reported in the United States as of April 20, 2022.

CDC Nowcast projections* for the week ending April 16, 2022, estimate the combined national proportion of lineages designated as Omicron to be 100%. There are several lineages of Omicron (B.1.1.529, BA.1, BA.2, BA.3, BA.4 and BA.5), and each one has multiple sublineages. COVID Data Tracker shows the proportions of Omicron lineages grouped as follows: the B.1.1.529 lineage (includes BA.1, BA.3, BA.4 and BA.5), the BA.1.1** lineage, the BA.2 lineage, and the BA.2.12.1 lineage. The predominant Omicron lineage in the United States is BA.2. The national proportion of BA.2 is projected to be 74.4% (95% PI 68.3-79.7%). The national proportion of BA.2.12.1 is projected to be 19.0% (95% PI 13.4-26.0%). BA.1.1 is projected to be 6.1% (95% PI 5.1-7.3%) and B.1.1.529 (BA.1, BA.3, BA.4 and BA.5) is projected to be 0.5% (95% PI 0.3-0.6%). Omicron is predicted to be 100% in all HHS regions.

80,648,481
Total Cases Reported

80,648,481
Total Cases Reported

42,605
Current 7-Day Average**

42,605
Current 7-Day Average**

31,495
Prior 7-Day Average

31,495
Prior 7-Day Average

35.3%
Change in 7-Day Average since Prior Week 

35.3%
Change in 7-Day Average since Prior Week 

*The median time from specimen collection to sequence data reporting is about 3 weeks. As a result, weighted estimates for the most recent few weeks may be unstable or unavailable. CDC’s Nowcast is a data projection tool that helps fill this gap by generating timely estimates of variant proportions for variants that are circulating in the United States. View Nowcast estimates on CDC’s COVID Data Tracker website on the Variant Proportions page.

**For national data, the proportion of BA.1.1 is shown separately. For regional data, the proportion of BA.1.1 is also aggregated with B.1.1.529.

***Historical cases are excluded from daily new cases and 7-day average calculations until they are incorporated into the dataset for the applicable date. Of 516,953 historical cases reported retroactively, 559 were reported in the current week and 4,203 were reported in the prior week.

Daily Trends in COVID-19 Cases in the United States Reported to CDC

red line

7-Day moving average

A bar graph showing daily trends in COVID-19 cases in the United States and a line with the 7-day moving average.

Vaccinations

The U.S. COVID-19 Vaccination Program began December 14, 2020. As of April 20, 2022, 570.5 million vaccine doses have been administered in the United States. Overall, about 256.9 million people, or 77.4% of the total U.S. population, have received at least one dose of vaccine. About 219.0 million people, or 66.0% of the total U.S. population, have been fully vaccinated.* Of those fully vaccinated, about 99.7 million people have received a booster dose,** but 49.6% of the total booster-eligible population has not yet received a booster dose. As of April 20, 2022, the 7-day average number of administered vaccine doses reported (by date of CDC report) to CDC per day was 470,903, a 13.2% decrease from the previous week.

CDC’s COVID Data Tracker displays vaccination trends by age group, race/ethnicity, and urban/rural status. To see trends by age group and race/ethnicity, visit the Vaccination Demographic Trends tab. To see trends by urban/rural status, visit  the COVID-19 Vaccination Equity tab.

570,485,199
Vaccine Doses Administered

570,485,199 Vaccine Doses Administered

570,485,199
Vaccine Doses Administered

256,935,026
People who received at least one dose

570,485,199 Vaccine Doses Administered

256,935,026
People who received at least one dose

219,047,079
People who are fully vaccinated*

219,047,079
People who are fully vaccinated*

77.4%
Percentage of the U.S. population that has received at least one dose

570,485,199 Vaccine Doses Administered

77.4%
Percentage of the U.S. population that has received at least one dose

66.0%
Percentage of the U.S. population that has been fully vaccinated*

66.0%
Percentage of the U.S. population that has been fully vaccinated*

+0.1
Percentage point increase from last week

570,485,199 Vaccine Doses Administered

+0.1
Percentage point increase from last week

+0.2
Percentage point increase from last week

+0.2
Percentage point increase from last week

*Represents the number of people who have received the second dose in a two-dose COVID-19 vaccine series (such as the Pfizer-BioNTech or Moderna vaccines) or one dose of the single-shot Johnson & Johnson’s Janssen vaccine.

**Represents the number of people who are fully vaccinated and have received another dose of COVID-19 vaccine since August 13, 2021. This includes people who received their first additional dose or booster dose.

Daily Change in the Total Number of Administered COVID-19 Vaccine Doses Reported to CDC by the Date of CDC Report, United States

red line

7-Day moving average

Chart showing Daily Change in the Total Number of Administered COVID-19 Vaccine Doses Reported to CDC by the Date of CDC Report, U.S.A. 04-22-2022

Hospitalizations

New Hospital Admissions

The current 7-day daily average for April 13–19, 2022, was 1,582. This is an 8.2% increase from the prior 7-day average (1,463) from April 6–12, 2022.

4,623,627
Total New Admissions

4,623,627
Total New Admissions

1,582
Current 7-Day Average

1,582
Current 7-Day Average

1,463
Prior 7-Day Average

1,463
Prior 7-Day Average

+8.2%
Change in 7-Day Average

+8.2%
Change in 7-Day Average

The start of consistent reporting of hospital admissions data was August 1, 2020.

Daily Trends in Number of New COVID-19 Hospital Admissions in the United States

A bar graph showing daily trends in number of new COVID-19 hospital admissions in the United States.

New admissions are pulled from a 10 am EDT snapshot of the HHS Unified Hospital Data – Analytic Dataset. Due to potential reporting delays, data from the most recent 7 days, as noted in the figure above with the grey bar, should be interpreted with caution. Small shifts in historic data may also occur due to changes in the Centers for Medicare & Medicaid Services (CMS) Provider of Services file, which is used to identify the cohort of included hospitals.

COVID-NET: Hospitalization Rates by Vaccination Status in Children Ages 5–11 Years

CDC’s Coronavirus Disease 2019-Associated Hospitalization Surveillance Network (COVID-NET) shows that rates of COVID-19-associated hospitalizations in February 2022 were 2 times as high among unvaccinated children ages 5–11 years compared to adolescents who received a COVID-19 primary vaccination series.*

Additional information on COVID-19-associated hospitalizations among children ages 5–11 years can be found in a new report using COVID-NET data here.

*Compared to older age groups, children ages 5–11 years have very low rates of hospitalization for any vaccination status. As a result, hospitalization rates by vaccination status for this age group might have more week-to-week variability due to small sample sizes.

Rates of COVID-19-Associated Hospitalizations by Vaccination Status in Children Ages 5–11 Years, January–February 2022

A line graph showing weekly rates of COVID-19-associated hospitalization among children ages 5-11, by vaccination status..

The Coronavirus Disease 2019 (COVID-19)-Associated Hospitalization Surveillance Network (COVID-NET) is an additional source for hospitalization data collected through a network of more than 250 acute-care hospitals in 14 states (representing ~10% of the U.S. population). Detailed data on patient demographics, including race/ethnicity, underlying medical conditions, medical interventions, and clinical outcomes, are collected using a standardized case reporting form.

More COVID-NET Data

Deaths

The current 7-day moving average of new deaths (376) has decreased 9.4% compared with the previous 7-day moving average (415). As of April 20, 2022, a total of 987,601 COVID-19 deaths have been reported in the United States.

987,601
Total Deaths Reported

987,601
Total Deaths Reported

376
Current 7-Day Average*

376
Current 7-Day Average*

415
Prior 7-Day Average

415
Prior 7-Day Average

-9.4%
Change in 7-Day Average Since Prior Week

-9.4%
Change in 7-Day Average Since Prior Week

*Historical deaths are excluded from the daily new deaths and 7-day average calculations until they are incorporated into the dataset by their applicable date. Of 21,064 historical deaths reported retroactively, 320 were reported in the current week; and none were reported in the prior week.

Daily Trends in Number of COVID-19 Deaths in the United States Reported to CDC

red line

7-Day moving average

A bar graph showing daily trends in number of COVID-19 deaths in the United States reported to CDC. More Death Data

Testing

The percentage of COVID-19 NAATs (nucleic acid amplification tests)* that are positive (percent positivity) is increasing in comparison to the previous week. The 7-day average of percent positivity from NAATs is now 5.3%. The 7-day average number of tests reported for April 8-14, 2022 was 727,146, down 6.7% from 779,004 for the prior 7 days.

863,827,004
Total Tests Reported

863,827,004 Total Tests Reported

863,827,004
Total Tests Reported

727,146
7-Day Average Tests Reported

863,827,004 Total Tests Reported

727,146
7-Day Average Tests Reported

5.3%
7-Day Average % Positivity

5.3%
7-Day Average % Positivity

3.7%
Previous 7-Day Average % Positivity

863,827,004 Total Tests Reported

3.7%
Previous 7-Day Average % Positivity

+1.58
Percentage point change in 7-Day Average % Positivity since Prior Week

+1.58
Percentage point change in 7-Day Average % Positivity since Prior Week

*Test for SARS-CoV-2, the virus that causes COVID-19

COVID-19 NAAT Laboratory Test 7-day Percent Positivity by State/Territory

A map of the United States with each state shaded according to COVID-19 NAAT laboratory test 7-day percent positivity.

Wastewater Surveillance

In February, CDC’s COVID Data Tracker released a Wastewater Surveillance tab, which tracks levels, changes, and detections of SARS-CoV-2 viral RNA in wastewater at more than 800 testing sites across the country. Because many people with COVID-19 shed the virus in their feces, wastewater testing can help us monitor COVID-19 in communities. Wastewater surveillance can provide an early warning of increasing COVID-19 cases and help communities prepare.

Currently, virus levels in wastewater are relatively low across the country. However, more than half of all sites reporting wastewater data are experiencing a modest increase in SARS-CoV-2 levels. These increases often reflect minor changes from very low levels to levels that are still low. It’s important to note that even a small increase when levels are low can appear like a dramatic increase in the percent change.

SARS-CoV-2 Levels in Wastewater by Site

A map of the U.S. showing wastewater surveillance locations, and the level of SARS-CoV-2 viral RNA detected at each location. white dot new site, blue dot 0% to 19%, light blue dot 20% to 39%, lightest blue dot 40% to 59%, orange dot 60% to 79%, red dot 80% to 100%

0% means levels are the lowest they have been at the site; 100% means levels are the highest they have been at the site.

More Wastewater Data