COVID-19 Data Dispatch

Tag: Omicron variant

  • National numbers, March 13

    National numbers, March 13

    Wastewater surveillance in the U.S. shows that we are currently in a plateau. Chart from Biobot, retrieved March 12.

    In the past week (March 5 through 11), the U.S. reported about 260,000 new COVID-19 cases, according to the CDC. This amounts to:

    • An average of 37,000 new cases each day
    • 79 total new cases for every 100,000 Americans
    • 29% fewer new cases than last week (February 26-March 4)

    In the past week, the U.S. also reported about 22,000 new COVID-19 patients admitted to hospitals. This amounts to:

    • An average of 3,100 new admissions each day
    • 6.6 total admissions for every 100,000 Americans
    • 28% fewer new admissions than last week

    Additionally, the U.S. reported:

    • 8,200 new COVID-19 deaths (2.5 for every 100,000 people)
    • 100% of new cases are Omicron-caused; 12% BA.2-caused (as of March 5)
    • An average of 100,000 vaccinations per day (per Bloomberg)

    Note: I’m shifting the format of these National Numbers posts to focus more on hospitalizations and wastewater, as case data become both less reliable and less available in many parts of the U.S.

    Overall, new COVID-19 cases are continuing to fall across the U.S. The country reported about 37,000 new cases a day last week, according to the CDC, compared to ten times that number in early February.

    Case numbers have become less reliable lately as testing sites close and people are redirected to use at-home rapid tests, which are generally not reported. Still, we’re seeing a similar trend in new COVID-19 patients admitted to hospitals: both new cases and new admissions dropped almost 30% last week from the week prior.

    Additionally, wastewater levels are decreasing or plateauing across the country, according to the Biobot tracker, which compiles trends from over 90 locations. The CDC wastewater surveillance tracker is showing similar overall trends as well.

    More than 98% of the U.S. population now lives in a location with a low or medium COVID-19 Community Level, according to the CDC. But a few places did see case increases last week: these include Nebraska, Kentucky, Alaska, and Delaware, according to the March 10 Community Profile Report.

    BA.2, the Omicron sister variant that is even more transmissible than the original version of this strain, is slowly gaining ground in the U.S.: it’s gone from causing an estimated 1% of cases in the first week of February to 12% in the first week of March, according to the CDC’s modeling.

    It hasn’t impacted case trends here yet, but deserves close attention in the coming weeks and months. Gothamist has a helpful article about BA.2’s potential impact in New York, where the variant’s prevalence in wastewater is doubling statewide every two weeks.

    Meanwhile, several European countries—including the U.K., Germany, the Netherlands, and others—reported case increases this week. This is likely due to ending pandemic safety measures, Omicron gaining its second wind, or some combination of the two; regardless, it doesn’t bode well for the U.S., which is also ending pretty much all pandemic safety measures.

    more national numbers
  • National numbers, March 6

    National numbers, March 6

    About 90% of the U.S. population now lives in a medium- or low-level COVID-19 “Community Level,” according to the CDC.

    In the past week (February 26 through March 4), the U.S. reported about 371,000 new COVID-19 cases, according to the CDC. This amounts to:

    • An average of 53,000 new cases each day
    • 113 total new cases for every 100,000 Americans
    • 29% fewer new cases than last week (February 19-25)

    Last week, America also saw:

    • 30,000 new COVID-19 patients admitted to hospitals (9 for every 100,000 people)
    • 11,000 new COVID-19 deaths (3.3 for every 100,000 people)
    • 100% of new cases are Omicron-caused (as of February 26)
    • An average of 140,000 vaccinations per day (per Bloomberg)

    New COVID-19 cases continue falling in the U.S. as the Omicron wave fizzles out. This week, the CDC reported an average of 53,000 new cases a day—less than one-tenth the cases reported at the peak of this surge.

    Hospitalization metrics also continue falling. About 30,000 new COVID-19 patients were admitted to U.S. hospitals this week, compared to almost 150,000 at the peak of the surge. According to the Hospital Circuit Breaker dashboard, only two states are currently at or over hospital capacity: Nebraska and Vermont.

    We’re now in the second week of the CDC’s new “Community Level” guidance for safety precautions tied to regional COVID-19 metrics. As of this week, “more than 90% of the U.S. population is in a location with low or medium COVID-19 Community Level,” according to the agency.

    Of course, the agency’s old guidance—still available on its COVID-19 dashboard—is less generous. According to these metrics, almost half of the country is still seeing “high community transmission,” with more than 100 new cases per 100,000 people in the last week. Remember, even though case numbers are much lower now than they were in early January, the Omicron surge warped our whole sense of COVID-19 proportion.

    Meanwhile, some parts of the country where Omicron arrived and peaked earlier are now in distinct plateaus. This includes Washington, D.C. and New York City; in NYC, case rates have actually started ticking back up very slightly in the last week.

    I personally trust NYC case numbers more than that metric in other places because the city still has widely available public testing. But as other cities and states close testing sites and redirect people to at-home tests, case numbers will continue becoming less reliable over the coming weeks. So, I am thinking about shifting these national updates to focus more on other metrics, like hospitalizations and wastewater.

    Readers, what do you think? Any recommendations for metrics you’d like to read more about here? Comment below or email me and let me know.

    more national numbers

  • Five more things, February 27

    Five additional news items from this week:

    • The CDC is not publicly releasing a lot of its COVID-19 data. Last weekend, New York Times reporter Apoorva Mandavilli broke the news that the CDC has withheld a lot of its COVID-19 data from the public, including information on breakthrough cases, demographic data, and wastewater data. This news was honestly not surprising to me because it follows a pattern: the CDC doesn’t like to share information unless it can control the interpretations. But I appreciated the conversation brought on by this article, with public health experts saying they’d rather have imperfect data than a complete data void. (I agree!)
    • BA.2 is definitely more transmissible than the original Omicron strain, but it does not appear to be significantly more severe or more capable of evading vaccines. Two recent posts, one in the New York Times COVID-19 updates page and one from Your Local Epidemiologist, share some updates on what scientists have learned about BA.2 in the past couple of weeks. In the U.S. and other countries with BA.2, this sublineage doesn’t seem to be causing a major rise in cases—at least so far.
    • New CDC study shows the utility of rapid testing out of isolation. More than half of patients infected with the coronavirus tested positive on rapid antigen tests between five and nine days after their initial diagnosis or symptom onset, a new CDC report found. The report includes over 700 patients at a rural healthcare network in Alaska. These findings suggest that rapid testing out of isolation is a good way to avoid transmitting the virus to others, if one has the tests available.
    • January saw record-high coronavirus infections in hospitals. POLITICO reporters analyzed hospitalization data from the Department of Health and Human Services (HHS), finding that: “More than 3,000 hospitalized patients each week in January had caught Covid sometime during their stay, more than any point of the pandemic.” This high number demonstrates Omicron’s high capacity to infect other people.
    • Hong Kong’s surge shows the value of vaccinations. Hong Kong has been a global leader in keeping COVID-19 cases low throughout the pandemic, yet Omicron has tested this territory’s strategy—causing record cases and overwhelming hospitals. One major issue for Hong Kong has been low vaccination rates, particularly among the elderly, as people did not see the need to get vaccinated when cases in the territory were practically nonexistent.
  • National numbers, February 27

    National numbers, February 27

    COVID-19 metrics are dropping across the board. Chart via Conor Kelly, posted on Twitter on February 23.

    In the past week (February 19 through 25), the U.S. reported about 526,000 new COVID-19 cases, according to the CDC. This amounts to:

    • An average of 75,000 new cases each day
    • 160 total new cases for every 100,000 Americans
    • 38% fewer new cases than last week (February 12-18)

    Last week, America also saw:

    • 42,000 new COVID-19 patients admitted to hospitals (13 for every 100,000 people)
    • 12,000 new COVID-19 deaths (3.6 for every 100,000 people)
    • 100% of new cases are Omicron-caused (as of February 19)
    • An average of 200,000 vaccinations per day (per Bloomberg)

    The U.S. is now on week six of falling COVID-19 case numbers nationwide. New cases fell 38% from last week to this week, and are down 87% from one month ago. This is also the first week that the country has reported a daily new case average under 100,000 since early December.

    Hospitalizations also continue to fall, with about 30% fewer new COVID-19 patients entering U.S. hospitals this week compared to last week. And death numbers have also begun to come down—though they are still high, with over 1,500 people dying of COVID-19 each day.

    Case numbers are falling in every single U.S. state; five states and D.C. reported fewer than 100 new cases for every 100,000 residents in the past week, according to the latest Community Profile Report: Washington, Nebraska, Maryland, Nevada, and Ohio. Last week, Maryland was the first state to report case numbers below the CDC’s old high transmission threshold. (The new threshold is higher, which I’ll get into later this issue.)

    To quote prolific COVID-19 data commentator (and my former COVID Tracking Project colleague) Conor Kelly, whose chart is featured above: “There’s not all that much interesting to report on with COVID data right now. Things are getting better fast everywhere. It’s just a question of how long it continues.”

    That continuation depends largely on variants. As the Omicron surge recedes, how long will we see these decreases (or a plateau at low numbers) before a new variant drives another surge? 

    One key factor here is BA.2, the Omicron sub-lineage that has been slowly gaining ground in the U.S. over the past month as it is more transmissible than original Omicron. And I do mean slowly: according to CDC estimates, BA.2 went from causing an estimated 2% of new cases in the week ending February 12 to 4% in the week ending February 19. It seems to be having a limited impact on the country’s case decrease right now, but we’ll see if that changes in the coming weeks.

    Meanwhile, America’s vaccination campaign is stalling. According to the Associated Press: “The average number of Americans getting their first shot is down to about 90,000 a day, the lowest point since the first few days of the U.S. vaccination campaign, in December 2020.” More investment into reaching people who remain unvaccinated (and unboosted) is necessary if we want to be prepared for potential future surges.

    more national numbers

  • Five more things, February 20

    A few additional news items from this week:

    • Omicron has caused more U.S. COVID-19 deaths than Delta. Despite numerous headlines proclaiming the Omicron variant to be “milder” than previous versions of the coronavirus, this variant infected such a high number of Americans that it still caused more deaths than previous waves, a new analysis by the New York Times shows. Between the end of November and this past week, the U.S. has reported over 30 million new COVID-19 cases and over 154,000 new deaths, the NYT found, compared to 11 million cases and 132,000 deaths from August 1 through October 31 (a period covering the worst of the Delta surge).
    • 124 countries are not on target to meet COVID-19 vaccination targets. The World Health Organization (WHO) set a target for all countries worldwide to have 70% of their populations fully vaccinated by mid-2022. As we approach the deadline, analysts at Our World in Data estimated how many countries have already met or are on track to meet the goal. They found: 124 countries are not on track to fully vaccinate 70% of their populations, including the U.S., Russia, Bangladesh, Egypt, Ethiopia, and other large nations.
    • Anime NYC was not an omicron superspreader event, CDC says. In early December, the Minnesota health department sounded the alarm about a Minnesotan whose COVID-19 case had been identified as Omicron—and who had recently traveled to New York City for the Anime NYC convention. The CDC investigated possible Omicron spread at this event, both by contact tracing the Minnesota case and by searching public health databases for cases connected to the event. Researchers found that this convention was not a superspreader for Omicron, despite what many feared; safety measures at the event likely played a role in preventing transmission, as did the convention’s timing at the very beginning of NYC’s Omicron wave. I covered the new findings for Science News.
    • Americans with lower socioeconomic status have more COVID-19 risk, new paper shows. Researchers at Brookings used large public databases to investigate the relationship between socioeconomic status and the risk of COVID-19 infections or death from the disease. Their paper, published this month in The ANNALS of the American Academy of Political and Social Science, found that education and income are major drivers of COVID-19 risk, as are race and ethnicity. The researchers also found that: “ socioeconomic status is not related to preventative behavior like mask use but is related to occupation-related exposure, which puts lower-socioeconomic-status households at risk.” 
    • The federal government has failed to disclose how much taxpayers are spending for “free” COVID-19 tests. One month into the Biden administration’s distribution of free at-home COVID-19 tests to Americans who request them, millions have received those tests. But the government has not shared how much it spent for the tests, making it difficult for journalists and researchers to determine how much taxpayer money was paid for each testing kit. “The reluctance to share pricing details flies against basic notions of cost control and accountability,” writes KHN reporter Christine Spolar in an article about this issue. The government has also failed to share details about who requested these free tests or when they were delivered, making it difficult to evaluate how equitable this distribution has been.

    Note: this title and format are inspired by Rob Meyer’s Weekly Planet newsletter.

  • National numbers, February 20

    National numbers, February 20

    The majority of U.S. counties are still seeing high transmission, according to the CDC, but a few places like Maryland and New York City are starting to fall below this threshold.

    In the past week (February 12 through 18), the U.S. reported about 850,000 new COVID-19 cases, according to the CDC. This amounts to:

    • An average of 122,000 new cases each day
    • 259 total new cases for every 100,000 Americans
    • 43% fewer new cases than last week (February 5-11)

    Last week, America also saw:

    • 60,000 new COVID-19 patients admitted to hospitals (18 for every 100,000 people)
    • 14,000 new COVID-19 deaths (4.3 for every 100,000 people)
    • 100% of new cases are Omicron-caused (as of February 12)
    • An average of 200,000 vaccinations per day (per Bloomberg)

    New COVID-19 cases continue to drop in the U.S. as the country slowly comes down from its Omicron wave. This week, the country reported a total of 850,000 new cases, according to the CDC; it’s the first week under one million new cases have been reported since early December, though we are still seeing over 100,000 new cases a day.

    Hospitalizations are also going down, with the Department of Health and Human Services reporting about 65,000 beds in use for confirmed and suspected COVID-19 patients as of Saturday. The hospital circuit breaker dashboard (by Jeremy Faust et al.) shows that the vast majority of U.S. hospitals have capacity, as of this week. Still, over 2,000 Americans continue to die of COVID-19 each day.

    At the state level, we continue to see case decreases across the country. The one exception is Maine: this state saw a 350% increase in cases from last week to this week, according to the February 17 Community Profile Report. However, local reports suggest that a number of the new cases reported this week were backlogged—meaning the cases occurred weeks ago and were belatedly added to state tallies.

    After over a month of falling case numbers nationwide, some parts of the country are finally dropping below the CDC’s high transmission threshold (100 new cases for every 100,000 residents reported in a week). Maryland is the first state to do this, with 92 new cases for every 100,000 residents reported in the week ending February 17.

    New York City, where I live, also fell below the high transmission threshold this week, with 83 new cases for every 100,000 residents reported in the week ending February 15, according to city data. Both New York City and Maryland were early Omicron hotspots and have reported falling case numbers since early January.

    While Omicron overall continues to cause 100% of new COVID-19 cases in the country, BA.2, the slightly-more-transmissible sister lineage, is starting to gain ground. The CDC estimates that BA.2 caused 3.9% of new cases in the week ending February 12, compared to 1.5% of new cases in the previous week. As BA.2 continues replacing original Omicron, we’ll see if this subvariant has an impact on the U.S.’s downward case trends.

    more national numbers
  • Omicron updates: BA.2, vaccine effectiveness, and more

    Omicron updates: BA.2, vaccine effectiveness, and more

    As of February 5, the CDC is now including BA.2 in its variant prevalence estimates. Screenshot from the CDC dashboard.

    A few Omicron-related news items for this week:

    • The CDC added BA.2 to its variant prevalence estimates. As I mentioned in today’s National Numbers post, the CDC is now splitting out its estimates of Omicron prevalence in the U.S. into original Omicron, also called B.1.1.529 or BA.1, and BA.2—a sister strain that’s capable of spreading faster than original Omicron. BA.2 has become the dominant variant in some parts of Europe and Asia, but seems to be present in the U.S. in fairly low numbers so far: the CDC estimates it caused about 3.6% of new cases nationwide in the week ending February 5, with a 95% confidence interval of 1.8% to 6.8%. The remainder of new cases last week were caused by original Omicron.
    • CDC describes its expanded genomic surveillance efforts in an MMWR study released this week. Between June 2021 and January 2022, the agency has extended its ability to monitor new variants spreading in the U.S., incorporating public repositories like GISAID into CDC data collection and developing modeling techniques that can produce more timely estimates of variant prevalence. (Remember: all variant data are weeks old, so the CDC uses modeling to predict the present.) According to the MMWR study, genomic sequencing capacity in the U.S. tripled from early 2021 to the second half of the year.
    • Vaccine effectiveness from a booster shot wanes several months after vaccination. In another MMWR study released this week, the CDC reports on mRNA vaccine effectiveness after two and three doses, based on data from a hospital network including hundreds of thousands of patients in 10 states. During the U.S.’s Omicron surge, researchers found, vaccine effectiveness against COVID-19 hospitalization was 91% two months after a third dose—but declined to 78% four months afterward. It’s unclear whether this declining effectiveness is a direct result of Omicron getting past the vaccine’s defenses, or whether we’d see similar declines with other variants. Also, the CDC’s findings are not stratified by age or other factors that make people more vulnerable to severe COVID-19.
    • Updated monoclonal antibody treatment from Eli Lilly gets FDA authorization. During the Omicron surge, one challenge for healthcare providers has been that, out of three monoclonal antibody treatments authorized by the FDA, only one retained effectiveness against this variant. (Monoclonal antibody treatments provide a boost to the immune system for vulnerable patients.) This week, however, the FDA authorized an updated version of Eli Lilly’s treatment that does work against Omicron, including against the BA.2 lineage. The federal government has purchased 600,000 courses of this new treatment.
    • More data released on South Africa’s mild Omicron wave. A new paper published in JAMA this week, from researchers at a healthcare provider in South Africa, compares COVID-19 hospitalizations during the Omicron surge to past surges. Among patients who visited the 49 hospitals in this provider’s network, about 41% of those who went to an emergency department with a positive COVID-19 test were admitted to the hospital during the Omicron surge—compared to almost 70% during South Africa’s prior surges. The paper provides additional evidence that Omicron is less likely to cause severe COVID-19 than past variants, though this likelihood is tied in part to high levels of vaccination and past infection in South Africa and other countries.
    • Omicron has been identified in white-tailed deer. New York City was an early Omicron hotspot in the U.S.; and the variant has been passed onto white-tailed deer in Staten Island, according to a new preprint posted this week (and not yet peer-reviewed). Scientists have previously identified coronavirus infections in 13 states, but finding Omicron is particularly concerning for researchers. “The circulation of the virus in deer provides opportunities for it to adapt and evolve,” Vivek Kapur, a veterinary microbiologist who was involved in the Staten Island study, told the New York Times. 

    More variant reporting

  • National numbers, February 13

    National numbers, February 13

    Current COVID-19 hospitalizations in the U.S. have fallen under 100,000 for the first time since the Omicron surge started. Chart by Conor Kelly, posted on Twitter on February 9.

    In the past week (February 5 through 11), the U.S. reported about 1.5 million new COVID-19 cases, according to the CDC. This amounts to:

    • An average of 215,000 new cases each day
    • 459 total new cases for every 100,000 Americans
    • One in 218 Americans testing positive for COVID-19
    • 43% fewer new cases than last week (January 29-February 4)

    Last week, America also saw:

    • 85,000 new COVID-19 patients admitted to hospitals (26 for every 100,000 people)
    • 16,000 new COVID-19 deaths (4.9 for every 100,000 people)
    • 100% of new cases are Omicron-caused (as of February 5)
    • An average of 300,000 vaccinations per day (per Bloomberg)

    COVID-19 cases continue to decline across the U.S. as the country comes out of its Omicron surge. Nationwide, the U.S. reported an average of 215,000 new cases a day last week—a drop of about 75% from the peak of the Omicron surge, when nearly 800,000 new cases were reported each day.

    Hospitalizations are also decreasing: this week, the number of confirmed and suspected COVID-19 patients in U.S. hospitals dropped under 100,000 for the first time since the surge started in December. Deaths are decreasing as well, but are still at high levels: over 2,000 Americans are dying of COVID-19 each day.

    All 50 states and the majority of counties continue to report case declines, according to the latest Community Profile Report. But case rates are still very high across the country, well above the CDC’s threshold for high transmission (more on this later in the issue).

    States with high case rates this week include Alaska, Kentucky, West Virginia, Montana, Mississippi, North Dakota, California, and Idaho; all reported over 700 new cases for every 100,000 residents in the week ending February 9.

    Omicron is still causing 100% of new cases in the country, according to CDC estimates. But the agency is now splitting its estimates into the original Omicron and its sister strain BA.2: BA.2 caused between 2% and 7% of new cases nationwide in the week ending February 5, the CDC says. In the coming weeks, we’ll see whether this strain—which is even more transmissible than original Omicron—has an impact on U.S. case numbers.

    New vaccination numbers have been fairly low for the past couple of weeks, with an average of under 300,000 shots given each day (including boosters). And the FDA is now delaying vaccine authorization for children under age 5: the agency has decided to wait for Pfizer to provide data on how well a three-dose series performs in this age group, after initially considering authorization based on data about two doses.

    more national numbers
  • Omicron updates: The continued importance of vaccination

    Omicron updates: The continued importance of vaccination

    COVID-19 deaths during the Omicron wave have been much higher in the U.S. than in other similarly wealthy countries, according to a New York Times analysis.

    Just a few updates for this week:

    • Scientists are still learning about BA.2, the more-transmissible Omicron offshoot. There haven’t been many major updates about BA.2 since last week, when I wrote this FAQ post; but this STAT News article by Andrew Joseph provides a helpful summary of what we know so far. The article explains that BA.2 clearly has a transmission advantage over BA.1 (and has now become the dominant variant in a few countries), but BA.1 may have spread around the world due to chance and some well-placed superspreading events. Notably, the CDC is not yet splitting out its Omicron prevalence estimates into BA.1 and BA.2, so we don’t have a great sense of how much this sub-lineage is spreading in the U.S.
    • More data indicates immune system memory remains strong against Omicron. In previous Omicron update posts, I’ve noted that, while vaccinated people are more likely to have a breakthrough case with Omicron than with past variants, vaccination is still highly protective against severe symptoms. A new study published in Nature this week further affirms this protection; researchers found that 70% to 80% of T cell response to Omicron was retained in people who were vaccinated or tested positive on antibody tests, compared to past variants. (T cells are key pieces of immune system memory response.)
    • Similarly, more data backs up the importance of vaccination to protect against severe disease during the Omicron era. The CDC released more MMWR studies this week showing that fully vaccinated and boosted Americans were less likely to require hospitalization or intensive care during the Omicron surge compared to the unvaccinated. For example, in Los Angeles County, California, hospitalization rates among unvaccinated people were 23 times higher than rates among those fully vaccinated with a booster, and five times higher than those vaccinated without a booster.

    • Omicron is too transmissible for school testing programs to keep up. I’ve previously reported on the challenges of K-12 COVID-19 testing programs, including the difficulty of setting up public health logistics, getting enough tests, and increasing polarization of testing. During the Omicron surge, these challenges have been magnified—to the point that some states, including Utah, Vermont, and Massachusetts, have suspended testing programs, POLITICO reported this week. I hope to see some of these programs resume after the surge is over.
    • The U.S.’s death toll during the Omicron surge has been far higher than in similarly wealthy nations. A new analysis from the New York Times compares the death toll in the U.S. from December 2021 through January 2022, adjusted for population, to death tolls in peer wealthy nations like Germany, Canada, Australia, and Japan. The comparison is striking: “the share of Americans who have been killed by the coronavirus is at least 63 percent higher than in any of these other large, wealthy nations,” the NYT reports. This difference is largely because the U.S. is less vaccinated than these other countries, particularly when it comes to booster shots and vaccinations among seniors.
    • Globally, cases during the Omicron surge surpassed all of 2020. “In the 10 weeks since Omicron was discovered, there have been 90 million COVID-19 cases reported — more than in all of 2020,” said Tedros Adhanom Ghebreyesus, Director-General of the World Health Organization, at a press conference last week. In a Twitter thread reporting from the press conference, STAT’s Helen Branswell noted that the WHO is concerned about countries “opening up” and lifting COVID-19 restrictions before their case numbers are actually low enough to warrant these measures.

    More variant reporting

  • Other Omicron updates: Healthcare system, treatments, and more

    Other Omicron updates: Healthcare system, treatments, and more

    A new CDC analysis found that Omicron led to record hospitalizations, but lower levels of ICU admissions and other indicators of the most severe disease compared to past surges. Chart via CDC MMWR.

    While BA.2 has dominated the news cycle this week, we’re still learning more about—and seeing policy shifts due to—the original Omicron strain, BA.1. Here are a few major updates:

    • Omicron is causing 100% of new COVID-19 cases in the U.S. According to the CDC’s latest update of its variant prevalence estimates, Omicron caused more than 99% of new COVID-19 cases in the country for the second week in a row: there was a slight increase from 99.4% of new cases in the week ending January 15 to 99.9% in the week ending January 22. The remaining 0.1% of cases are caused by Delta. The CDC is not yet distinguishing between BA.1 and BA.2 in its estimates, but will likely start doing so in the coming weeks.
    • ICU admissions and other indicators of severe COVID-19 symptoms were lower during the Omicron surge than during previous surges in the U.S. The CDC released another round of studies presenting Omicron’s impact on the healthcare system last week, including this report focusing on disease severity. CDC researchers analyzed data from three hospital surveillance systems and an additional large database; while the peak of new COVID-19 cases was five times higher during the Omicron surge than the Delta surge, they found, the peak of hospital admissions was only 1.8 times higher. And ICU admissions, the average stay length for hospitalized COVID-19 patients, and death rates were all lower during the Omicron surge than in the Delta and winter 2020-2021 surges.
    • Pfizer and BioNTech have started a clinical trial of an Omicron-specific vaccine. Quickly after Omicron was identified, both Pfizer and Moderna started updating their vaccines for this variant and investigating whether such Omicron-specific shots would be necessary. Pfizer is now entering a new clinical trial with its Omicron-specific shot, along with its vaccine development partner BioNTech, according to Reuters. Trial participants will include about 1,400 people who received third doses from Pfizer’s current COVID-19 vaccine regimen three to six months earlier. Pfizer intends to study the Omicron-specific shot’s safety and effectiveness against this variant.

    • The FDA recommends that U.S. facilities stop using monoclonal antibody treatments that don’t work well against Omicron. Speaking of Omicron-specific drugs: the Food and Drug Administration (FDA) announced this week that the agency is limiting use of two monoclonal antibody treatments, made by Regeneron and Eli Lilly. Both treatments, which boost patients’ immune systems by providing them with lab-made antibodies, worked well at reducing severe symptoms for past variants but have less of an impact on Omicron infections. As a result, healthcare providers should “ limit their use to only when the patient is likely to have been infected with or exposed to a variant that is susceptible to these treatments,” the FDA says. A third monoclonal antibody treatment, along with other drugs (including Pfizer’s hard-to-find pill), do work well against Omicron.
    • Omicron has a short incubation period, so test timing is key. As I’ve written in the past, Omicron infections tend to move more quickly than infections with past variants: people can go from an exposure to symptoms within three days, rather than four or five. As a result, there’s less time to catch an infection before becoming contagious; but at the same time, rapid tests may give negative results in those early days of an infection, before patients have built up enough of a viral load for an antigen test to identify the infection. A recent New York Times article summarizes the science on how Omicron infections compare to past variants and provides recommendations on testing. For instance: “many experts now recommend taking a rapid test two to four days after a potential exposure,” and ideally testing twice about a day apart.
    • Some experts are optimistic that we could see a COVID-19 lull after Omicron surges. Last week, I shared a STAT News article explaining that, thanks to high levels of population immunity, the U.S. might have “a bit of a break from the Covid roller coaster” after our Omicron surge ends in the coming weeks. Despite BA.2 concerns, Dr. Hans Henri Kluge, WHO’s regional director for Europe, shared a similarly optimistic view in a statement last week. “The pandemic is far from over, but I am hopeful we can end the emergency phase in 2022 and address other health threats that urgently require our attention,” he said.

    More variant reporting