Posted on by Lawrence Tabak, D.D.S., Ph.D.
More than 215 million people in the United States are now fully vaccinated against the SARS-CoV-2 virus responsible for COVID-19 . More than 40 percent—more than 94 million people—also have rolled up their sleeves for an additional, booster dose. Now, an NIH-funded study exploring how mRNA vaccines are performing over time comes as a reminder of just how important it will be to keep those COVID-19 vaccines up to date as coronavirus variants continue to circulate.
The results, published in the journal Science Translational Medicine, show that people who received two doses of either the Pfizer or Moderna COVID-19 mRNA vaccines did generate needed virus-neutralizing antibodies . But levels of those antibodies dropped considerably after six months, suggesting declining immunity over time.
The data also reveal that study participants had much reduced protection against newer SARS-CoV-2 variants, including Delta and Omicron. While antibody protection remained stronger in people who’d also had a breakthrough infection, even that didn’t appear to offer much protection against infection by the Omicron variant.
The new study comes from a team led by Shan-Lu Liu at The Ohio State University, Columbus. They wanted to explore how well vaccine-acquired immune protection holds up over time, especially in light of newly arising SARS-CoV-2 variants.
This is an important issue going forward because mRNA vaccines train the immune system to produce antibodies against the spike proteins that crown the surface of the SARS-CoV-2 coronavirus. These new variants often have mutated, or slightly changed, spike proteins compared to the original one the immune system has been trained to detect, potentially dampening the immune response.
In the study, the team collected serum samples from 48 fully vaccinated health care workers at four key time points: 1) before vaccination, 2) three weeks after the first dose, 3) one month after the second dose, and 4) six months after the second dose.
They then tested the ability of antibodies in those samples to neutralize spike proteins as a correlate for how well a vaccine works to prevent infection. The spike proteins represented five major SARS-CoV-2 variants. The variants included D614G, which arose very soon after the coronavirus first was identified in Wuhan and quickly took over, as well as Alpha (B.1.1.7), Beta (B.1.351), Delta (B.1.617.2), and Omicron (B.1.1.529).
The researchers explored in the lab how neutralizing antibodies within those serum samples reacted to SARS-CoV-2 pseudoviruses representing each of the five variants. SARS-CoV-2 pseudoviruses are harmless viruses engineered, in this case, to bear coronavirus spike proteins on their surfaces. Because they don’t replicate, they are safe to study without specially designed biosafety facilities.
At any of the four time points, antibodies showed a minimal ability to neutralize the Omicron spike protein, which harbors about 30 mutations. These findings are consistent with an earlier study showing a significant decline in neutralizing antibodies against Omicron in people who’ve received the initial series of two shots, with improved neutralizing ability following an additional booster dose.
The neutralizing ability of antibodies against all other spike variants showed a dramatic decline from 1 to 6 months after the second dose. While there was a marked decline over time after both vaccines, samples from health care workers who’d received the Moderna vaccine showed about twice the neutralizing ability of those who’d received the Pfizer vaccine. The data also suggests greater immune protection in fully vaccinated healthcare workers who’d had a breakthrough infection with SARS-CoV-2.
In addition to recommending full vaccination for all eligible individuals, the Centers for Disease Control and Prevention (CDC) now recommends everyone 12 years and up should get a booster dose of either the Pfizer or Moderna vaccines at least five months after completing the primary series of two shots . Those who’ve received the Johnson & Johnson vaccine should get a booster at least two months after receiving the initial dose.
While plenty of questions about the durability of COVID-19 immunity over time remain, it’s clear that the rapid deployment of multiple vaccines over the course of this pandemic already has saved many lives and kept many more people out of the hospital. As the Omicron threat subsides and we start to look forward to better days ahead, it will remain critical for researchers and policymakers to continually evaluate and revise vaccination strategies and recommendations, to keep our defenses up as this virus continues to evolve.
 COVID-19 vaccinations in the United States. Centers for Disease Control and Prevention. February 27, 2022.
 Neutralizing antibody responses elicited by SARS-CoV-2 mRNA vaccination wane over time and are boosted by breakthrough infection. Evans JP, Zeng C, Carlin C, Lozanski G, Saif LJ, Oltz EM, Gumina RJ, Liu SL. Sci Transl Med. 2022 Feb 15:eabn8057.
 COVID-19 vaccine booster shots. Centers for Disease Control and Prevention. Feb 2, 2022.
COVID-19 Research (NIH)
Shan-Lu Liu (The Ohio State University, Columbus)
NIH Support: National Institute of Allergy and Infectious Diseases; National Cancer Institute; National Heart, Lung, and Blood Institute; Eunice Kennedy Shriver National Institute of Child Health and Human Development
Posted on by Dr. Francis Collins
With most kids now back in school, parents face a new everyday concern: determining whether their child’s latest cough or sneeze might be a sign of COVID-19. If so, parents will want to keep their child at home to protect other students and staff, while also preventing the spread of the virus in their communities. And if it’s the parent who has a new cough, they also will want to know if the reason is COVID-19 before going to work or the store.
Home tests are now coming online to help concerned people make the right choice quickly. As more COVID-19 home tests enter the U.S. marketplace, research continues to help optimize their use. That’s why NIH and the Centers for Disease Control and Prevention (CDC) are teaming up in several parts of the country to provide residents age 2 and older with free home-testing kits for COVID-19. These reliable, nasal swab tests provide yes-or-no answers in about 15 minutes for parents and anyone else concerned about their possible exposure to the novel coronavirus.
The tests are part of an initiative called Say Yes! COVID Test (SYCT) that’s evaluating how best to implement home-testing programs within range of American communities, both urban and rural. The lessons learned are providing needed science-based data to help guide public health officials who are interested in implementing similar home-testing programs in communities throughout their states.
After successful eight-week pilot programs this past spring and summer in parts of North Carolina, Tennessee, and Michigan, SYCT is partnering this fall with four new communities. They are Fulton County, GA; Honolulu County, HI; Louisville Metro, KY; and Marion County, IN.
The Georgia and Hawaii partnerships, launched on September 20, are already off to a flying start. In Fulton County, home to Atlanta and several small cities, 21,673 direct-to-consumer orders (173,384 tests) have already been received. In Honolulu County, demand for the tests has exceeded all expectations, with 91,000 orders received in the first week (728,000 tests). The online ordering has now closed in Hawaii, and the remaining tests will be distributed on the ground through the local public health department.
SYCT offers the Quidel QuickVue® At-Home COVID-19 test, which is supplied through the NIH Rapid Acceleration of Diagnostics (RADx) initiative. The antigen test uses a self-collected nasal swab sample that is placed in a test tube containing solution, followed by a test strip. Colored lines that appear on the test strip indicate a positive or negative result—similar to a pregnancy test.
The program allows residents in participating counties to order free home tests online or for in-person pick up at designated sites in their community. Each resident can ask for eight rapid tests, which equals two weekly tests over four weeks. An easy-to-navigate website like this one and a digital app, developed by initiative partner CareEvolution, are available for residents to order their tests, sign-up for testing reminders, and allow voluntary test result reporting to the public health department.
SYCT will generate data to answer several important questions about self or home-testing. They include questions about consumer demand, ensuring full community access, testing behavior, willingness to report test results, and, above all, effectiveness in controlling the spread of SARS-CoV-2, the coronavirus that causes COVID-19
Researchers at the University of North Carolina-Chapel Hill; Duke University, Durham, NC; and the UMass Chan Medical School, Worcester, MA, will help crunch the data and look for guiding themes. They will also conduct a study pre- and post-intervention to evaluate levels of SARS-CoV-2 in the community, including using measures of virus in wastewater. In addition, researchers will compare their results to other counties similar in size and infection rates, but that are not participating in a free testing initiative.
The NIH and CDC are exploring ways to scale a SYCT-like program nationally to communities experiencing surges in COVID-19. The Biden Administration also recently invoked the Defense Production Act to purchase millions of COVID-19 home tests to help accelerate their availability and offer them at a lower cost to more Americans. That encompasses many different types of people, including concerned parents who need a quick-and-accurate answer on whether their children’s cough or sneeze is COVID-19.
COVID-19 Research (NIH)
Rapid Acceleration of Diagnostics (RADx) (NIH)
NIH Support: National Institute of Biomedical Imaging and Bioengineering; National Heart, Lung, and Blood Institute; National Institute on Minority Health and Health Disparities
Posted on by Dr. Francis Collins
At the end of last year, you may recall hearing news reports that the number of COVID-19 cases in the United States had topped 20 million. While that number came as truly sobering news, it also likely was an underestimate. Many cases went undetected due to limited testing early in the year and a large number of infections that produced mild or no symptoms.
Now, a recent article published in Nature offers a more-comprehensive estimate that puts the true number of infections by the end of 2020 at more than 100 million . That’s equal to just under a third of the U.S. population of 328 million. This revised number shows just how rapidly this novel coronavirus spread through the country last year. It also brings home just how timely the vaccines have been—and continue to be in 2021—to protect our nation’s health in this time of pandemic.
The work comes from NIH grantee Jeffrey Shaman, Sen Pei, and colleagues, Columbia University, New York. As shown above in the map, the researchers estimated the percentage of people who had been infected with SARS-CoV-2, the novel coronavirus that causes COVID-19, in communities across the country through December 2020.
To generate this map, they started with existing national data on the number of coronavirus cases (both detected and undetected) in 3,142 U.S. counties and major metropolitan areas. They then factored in data from the Centers for Disease Control and Prevention (CDC) on the number of people who tested positive for antibodies against SARS-CoV-2. These CDC data are useful for picking up on past infections, including those that went undetected.
From these data, the researchers calculated that only about 11 percent of all COVID-19 cases were confirmed by a positive test result in March 2020. By the end of the year, with testing improvements and heightened public awareness of COVID-19, the ascertainment rate (the number of infections that were known versus unknown) rose to about 25 percent on average. This measure also varied a lot across the country. For instance, the ascertainment rates in Miami and Phoenix were higher than the national average, while rates in New York City, Los Angeles, and Chicago were lower than average.
How many people were potentially walking around with a contagious SARS-CoV-2 infection? The model helps to answer this, too. On December 31, 2020, the researchers estimate that 0.77 percent of the U.S. population had a contagious infection. That’s about 1 in every 130 people on average. In some places, it was much higher. In Los Angeles, for example, nearly 1 in 40 (or 2.42 percent) had a SARS-CoV-2 infection as they rang in the New Year.
Over the course of the year, the fatality rate associated with COVID-19 dropped, at least in part due to earlier diagnosis and advances in treatment. The fatality rate went from 0.77 percent in April to 0.31 percent in December. While this is great news, it still shows that COVID-19 remains much more dangerous than seasonal influenza (which has a fatality rate of 0.08 percent).
Today, the landscape has changed considerably. Vaccines are now widely available, giving many more people immune protection without ever having to get infected. And yet, the rise of the Delta and other variants means that breakthrough infections and reinfections—which the researchers didn’t account for in their model—have become a much bigger concern.
Looking ahead to the end of 2021, Americans must continue to do everything they can to protect their communities from the spread of this terrible virus. That means getting vaccinated if you haven’t already, staying home and getting tested if you’ve got symptoms or know of an exposure, and taking other measures to keep yourself and your loved ones safe and well. These measures we take now will influence the infection rates and susceptibility to SARS-CoV-2 in our communities going forward. That will determine what the map of SARS-CoV-2 infections will look like in 2021 and beyond and, ultimately, how soon we can finally put this pandemic behind us.
 Burden and characteristics of COVID-19 in the United States during 2020. Pei S, Yamana TK, Kandula S, Galanti M, Shaman J. Nature. 2021 Aug 26.
COVID-19 Research (NIH)
Sen Pei (Columbia University, New York)
Jeffrey Shaman (Columbia University, New York)
Posted on by Dr. Francis Collins
Recently, there is a new and very hopeful COVID-19 number for everyone to track: the total number of vaccine doses that have been administered in the United States. If 80 percent of Americans roll up their sleeves in the coming months and accept COVID-19 vaccinations, we can greatly slow the spread of the novel coronavirus in our communities and bring this horrible pandemic to an end in 2021.
So far, more than 20 million people in our country have received one or two doses of either the Pfizer or Moderna vaccine. While this number is lower than initially projected for a variety of logistical reasons, we’re already seeing improvements in the distribution system that has made it possible to get close to 1 million doses administered per day.
If you want to keep track of the vaccine progress in your state over the coming weeks, it’s now pretty easy to do online. A fine resource is the vaccine information on the Centers for Disease Control and Prevention (CDC) COVID Data Tracker. It offers an interactive state-by-state map, as well as data on vaccinations in long-term care facilities. Keep in mind that there’s a delay of three to five days in reporting actual vaccinations from the states.
There’s also a lot of useful information on the Johns Hopkins Coronavirus Resource Center’s Vaccine Tracker. Posting the daily updates is a team, led by William Moss, that draws on the expertise of data scientists, analysts, programmers, and researchers. The Hopkins team gathers its vaccination data from each state’s official dashboard, webpages, press releases, or wherever cumulative numbers are reported. Not all states publish the same vaccine information, and that’s what can make the Vaccine Tracker so challenging to compile.
The Hopkins team now presents on its homepage the top 10 U. S. states and territories to vaccinate fully the highest percentage of their residents. With another click, there’s also a full rundown of vaccine administration by state and territory, plus the District of Columbia. The site also links to lots of other information about COVID-19—including cases, testing, contact tracing, and an interactive tool about vaccine development.
In uncertain times, knowledge can be a source of comfort. That’s what makes these interactive COVID-19 resources so helpful and empowering. They show that, with time, safe and effective COVID-19 vaccines will indeed coming to everyone. I hope that you will accept your vaccine, like I did when given the opportunity. However, until we get to the point where most Americans are immunized, we must stay vigilant and keep up our tried-and-true public health measures such as wearing masks, limiting physical interactions (especially indoors), and washing our hands.
COVID-19 Research (NIH)
CDC COVID Data Tracker (Centers for Disease Control and Prevention, Atlanta)
Coronavirus Resource Center (Johns Hopkins University School of Medicine)
William Moss (Johns Hopkins University, Baltimore)
International Vaccine Access Center (Johns Hopkins Bloomberg School of Public Health, Baltimore)