COVID-19 Data Dispatch

Tag: b.1.1.7. variant

  • New CDC page on variants still leaves gaps

    New CDC page on variants still leaves gaps

    This week, the CDC published a new data page about the coronavirus variants now circulating in the U.S. The page provides estimates of how many new cases in the country may be attributed to different SARS-CoV-2 lineages, including both more familiar, wild-type variants (B.1. and B.1.2) and newer variants of concern.

    This new page is a welcome addition to the CDC’s library, as their “Cases Caused by Variants” page only provides numbers of variant cases reported to the agency—which, as we have repeatedly stated at the CDD, represent huge undercounts.

    However, the page still has three big problems:

    First, the data are old. The CDC is currently reporting data for four two-week periods, the most recent of which ends February 27. That’s a full three weeks ago—a pretty significant lag when several “variants of concern” are concerning precisely because they are more infectious, meaning they can spread through the population more quickly.

    The CDC’s B.1.1.7 estimate (about 9% as of Feb. 27) particularly sticks out. CoVariants, a variant tracker run by independent researcher Emma Hodcroft, also puts B.1.1.7 prevalence in the U.S. at about 10% in late February… but estimates this variant accounts for 22% of sequences as of March 8. These estimates indicate that B.1.1.7 may have doubled its case counts in the two weeks after the CDC’s data stop.

    Second, the CDC data reveal geographic gaps in our current sequencing strategy. The CDC is providing state-by-state prevalence estimates for 19 select states—or, those states that are doing a lot of genomic sequencing. Of course, this includes big states such as California and New York, but excludes much of the Midwest and other smaller, less scientifically-endowed states.

    Michigan, that state currently facing a concerning surge, is not represented—even though the state has one of the highest raw counts of B.1.1.7 cases, as of this week. We can gather from a footnote that Michigan did not submit at least 300 sequences to the CDC between January 13 and February 13; still, this exclusion poses a challenge for researchers watching that surge.

    And finally, the data are presented in a confusing manner. When I shared this page with a couple of COVID Tracking Project friends on Friday, it took the group a lot of close-reading and back-and-forth to unpack those first two problems. And we’re all used to puzzling through confusing data portals! The CDC claims this page is an up-to-date tracker, “used to inform national and state public health actions related to variants,” but its data are weeks old and represent less than half of the country.

    The CDC needs to improve its communication of data gaps, lags, and uncertainties, especially on such an alarming topic as variants. And, of course, we need better variant data to begin with. The U.S. is aiming to sequence 25,000 samples per week, but that’s still far from the 5% of new cases we would need to sequence in order to develop an accurate picture of variant spread in the U.S.

    On that note: you may notice that we now have a new category for variant posts on the CDD website. I expect that this will continue to be a major topic for us going forward.

    Related posts

    • Some optimistic vaccine news but variants still pose a major threat

      Some optimistic vaccine news but variants still pose a major threat

      Last week, Janssen, a pharmaceutical division owned by megacorp Johnson & Johnson, released results for its phase 3 ENSEMBLE study. The Janssen vaccine uses an adenovirus vector (a modified common cold virus that delivers the DNA necessary to make the coronavirus spike protein), can be stored at normal fridge temperatures, and only requires one dose. Here’s a table of the raw numbers from Dr. Akiko Iwasaki of Yale:

      At first glance it does look like it’s “less effective” than the mRNA vaccines from Moderna and Pfizer. But, when you look at the severe disease, there’s a 100% decrease in deaths. No one who got the J&J vaccine died of coronavirus, no matter where they lived— including people who definitely were diagnosed with the South African B.1.351 variant. Here’s how that compares with the Moderna, AstraZeneca, Pfizer, and Novavax vaccines, per Dr. Ashish Jha of Brown:

      Nobody who got any of the vaccine candidates was hospitalized or died from COVID-19. That’s huge, especially as variants continue to spread across the U.S. (Here’s the updated CDC variant tracker.)

      J&J’s numbers are especially promising when it comes to variant strains. Moderna and Pfizer released their results before the B.1.1.7 (U.K.) or B.1.351. (S.A.) variants reached their current notoriety, which makes J&J’s overall efficacy numbers look worse by comparison. But the fact that no one who got the J&J vaccine was hospitalized no matter which variant they were infected with is a cause for optimism. (B.1.351 is the variant raising alarms for possibly being able to circumvent a vaccine’s protection due to a helpful mutation called E484K. A Brazilian variant, P1, also has this mutation, though there’s not a lot of research on vaccine efficacy for this particular mutant.)

      It also means that vaccination needs to step up. While it may seem counterintuitive to step up vaccinations against variants that can supposedly circumvent them, it’s important to note that there still was a significant decrease in COVID-19 cases in vaccinated patients from South Africa. A 57% drop compared with the 95% prevalence of the B.1.351 still suggests that vaccination can prevent these cases, and thus can seriously slow the spread of the variant.

      What does all of this mean for COVID-19 rates? We can infer a few things. For starters, when vaccines are distributed to the general public around April or May, we may see hospitalization rates and death rates drop more than positive test rates. Positive test rates should obviously drop too, but they’ll probably stay at least a little higher than hospitalizations and death rates for a while.

      Second, it means that we really need to ramp up sequencing efforts in the U.S.. We need more data to tell us just how well these vaccines can protect against the spreading variants, but we can’t collect that data if we don’t know which strain of SARS-CoV-2 someone gets. We here at the CDD have covered sequencing efforts – or lack thereof – before, but the rollout has still been painfully slow. CDC Director Rochelle Walensky stressed that “we should be treating every case as if it’s a variant during this pandemic right now,” during the January 29 White House coronavirus press briefing. But the 6,000 sequences per week she’s pushing for as of the February 1 briefing should have been the benchmark months ago. We’re still largely flying blind until we can get our act together.

      Some states in particular may be flying blinder than others. As Caroline Chen wrote in ProPublica yesterday, governors of New York, Michigan, Massachusetts, California, and Idaho are planning to relax more restrictions, including those on indoor dining. Such a plan is probably the perfect way to ensure these variants spread, so much that even Chen was surprised at how pessimistic the outlook was when she asked 10 scientists for the piece.

      The B.1.1.7 variant is expected to become the dominant strain in the U.S. by March, according to the CDC. And on top of that, the B.1.1.7 variant seems to have picked up that helpful E484K mutation in some cases as well. Per Angela Rasmussen of Georgetown University, if these governors don’t realize how much they’re about to screw everything up, “the worst could be yet to come.” God help us.

      more vaccine coverage
    • We’re not doing enough sequencing to detect B.1.1.7

      We’re not doing enough sequencing to detect B.1.1.7

      The CDC has identified 63 cases of the B.1.1.7 variant as of Jan. 8, but this is likely a significant undercount thanks to the nation’s lack of systematic sequencing.

      A new, more transmissible strain of COVID-19 (known as B.1.1.7) has caused quite a stir these past few weeks. It surfaced in the United Kingdom and has been detected in eight states: California, Colorado, Connecticut, Florida, Georgia, New York, Texas, and Pennsylvania. The fact that a mutant strain happened isn’t a surprise, as RNA viruses mutate quite often. But as vaccines roll out, the spread of a new strain is yet another reminder that we’re nowhere near out of the woods yet.  

      It’s entirely possible to differentiate between strains of SARS-CoV-2 through genetic testing. To detect the B.1.1.7 variant, COVID-19 positive samples can be sequenced to search for a telltale deletion in the virus’s RNA. And in theory, we could track the spread of this variant with good testing data. A truly robust tracking effort should include a centralized surveillance program to sequence the RNA of the SARS-CoV-2 virus in all positive cases—or at least a good sample—to detect any mutant strains and track their impact. However, this is an area where the US has consistently faltered: as of December 23rd, only 51,212 out of 18 million positive cases had been sequenced. 

      As with most of the government’s response, handling this seems to be mostly up to the states. According to releases from Colorado, Pennsylvania, Connecticut, and Texas, it looks like these states are making sequencing efforts. Georgia said, “The variant was discovered during analysis of a specimen sent by a pharmacy in Georgia to a commercial lab”, which I can only assume means they have been conducting some kind of sequencing effort. I couldn’t find references to the extent of sequencing efforts in the announcements from California, Florida, or New York. 

      From these releases, it’s obvious that there is no unified cross-state effort. Pennsylvania stated that they had been sending “10-35 random samples biweekly to the CDC since November to study sequencing,” but that’s not going to be nearly enough to track this more transmissible variant. Are there any plans to ramp up sequencing? And that’s just from Pennsylvania because they deigned to tell us—are all states going to ramp up sequencing? It’s just not clear. 

      And after all that, starting to test for the variant now still won’t tell us just how widespread it is. The first case in New York was in someone with no evident travel history. Indeed, this is true for most people who have been infected, and, per Dr. Angela Rasmussen in Buzzfeed News, this suggests that the variant is already circulating in the community. To know how widespread the variant is, we would need to retroactively test samples that had already tested positive. Colorado’s press release mentioned that they would be doing some retroactive testing, but what about the other seven states? 

      Plus, that’s just states with already confirmed cases—there absolutely will be more confirmed cases in other states, because if it is already present in the community, there probably already are cases in other states. To know just where this variant is, every positive test in the US stretching back months into the past would have to be retroactively re-tested for the variant—an unlikely occurrence. 

      Even if there were a coordinated effort to retroactively sequence all positive tests, some cases of the variant could still slip through the cracks, because most states still aren’t doing enough PCR testing as it is. As of January 8th, according to Ashish Jha’s team at the Brown University School of Public Health, 86% of states aren’t meeting their testing targets. (Meeting testing targets indicates that enough testing is happening to “identify most people reporting symptoms and at least two of their close contacts.” State targets on this dashboard were last configured on October 1, so keep that in mind.) Only two states where the variant has surfaced, Connecticut and New York, are meeting their targets—and cases are surging in both states right now. Longtime readers are going to be very familiar with this problem, but if any new people are reading, this means that in most states we don’t even know how widespread our “garden variety” COVID-19 is. So how are we supposed to know where the UK variant is if we can’t even keep track of the virus that’s been here for almost a year? 

      Beyond testing, even reporting on confirmed cases of the variant is spotty at best. The CDC is reporting how many detected cases of COVID-19 have been caused by the variant, but no state with a confirmed case caused by B.1.1.7 is displaying that data on their dashboard. (I checked the 8 states’ dashboards and left a comment on California’s because the ask box was right there.) Why is this not on their dashboards? I couldn’t tell you, but it seems like important information that should be reported.

      All of these unanswered questions show, yet again, that we desperately need a unified effort from the federal government to track and combat this virus. It should not be this hard to find how we’re tracking the spread of this variant, it should not be this hard to tell which methods work for even identifying the variant, and it should at least be possible to find this data on state health dashboards. It might look like we’re close to the finish line as vaccines continue to be distributed, but we’re tripping over the exact same problems we did at the beginning. 

      more testing data