Oxford University
Study of Healthcare Workers Shows COVID-19 Immunity Lasts Many Months
Posted on by Dr. Francis Collins
Throughout the COVID-19 pandemic, healthcare workers around the world have shown willingness to put their own lives on the line for their patients and communities. Unfortunately, many have also contracted SARS-CoV-2, the coronavirus that causes of COVID-19, while caring for patients. That makes these frontline heroes helpful in another way in the fight against SARS-CoV-2: determining whether people who have recovered from COVID-19 can be reinfected by the virus.
New findings from a study of thousands of healthcare workers in England show that those who got COVID-19 and produced antibodies against the virus are highly unlikely to become infected again, at least over the several months that the study was conducted. In the rare instances in which someone with acquired immunity for SARS-CoV-2 subsequently tested positive for the virus within a six month period, they never showed any signs of being ill.
Some earlier studies have shown that people who survive a COVID-19 infection continue to produce protective antibodies against key parts of the virus for several months. But how long those antibodies last and whether they are enough to protect against reinfection have remained open questions.
In search of answers, researchers led by David Eyre, University of Oxford, England, looked to more than 12,000 healthcare workers at Oxford University Hospitals from April to November 2020. At the start of the study, 11,052 of them tested negative for antibodies against SARS-CoV-2, suggesting they hadn’t had COVID-19. But the other 1,246 tested positive for antibodies, evidence that they’d already been infected.
After this initial testing, all participants received antibody tests once every two months and diagnostic tests for an active COVID-19 infection at least every other week. What the researchers discovered was rather interesting. Eighty-nine of the 11,052 healthcare workers who tested negative at the outset later got a symptomatic COVID-19 infection. Another 76 individuals who originally tested negative for antibodies tested positive for COVID-19, despite having no symptoms.
Here’s the good news: Just three of these more than 1400 antibody-positive individuals subsequently tested positive for SARS-CoV-2. What’s more, not one of them had any symptoms of COVID-19.
The findings, which were posted as a pre-print on medRxiv, suggest that acquired immunity from an initial COVID-19 infection offers protection against reinfection for six months or maybe longer. Questions remain about whether the acquired immunity is due to the observed antibodies alone or their interplay with other immune cells. It will be important to continue to follow these healthcare workers even longer, to learn just how long their immune protection might last.
Meanwhile, more than 15 million people in the United States have now tested positive for COVID-19, leading to more than 285,000 deaths. Last week, the U.S. reported for the first time more than 200,000 new infections, with hospitalizations and deaths also on the rise.
While the new findings on reinfection come as good news to be sure, it’s important to remember that the vast majority of the 328 million Americans still remain susceptible to this life-threatening virus. So, throughout this holiday season and beyond—as we eagerly await the approval and widespread distribution of vaccines—we must all continue to do absolutely everything we can to protect ourselves, our loved ones, and our communities from COVID-19.
Reference:
[1] Antibodies to SARS-CoV-2 are associated with protection against reinfection. Lumley, S.F. et al. MedRxiv. 19 November 2020.
Links:
Coronavirus (COVID) (NIH)
Combat COVID (U.S. Department of Health and Human Services, Washington, D.C.)
David Eyre (University of Oxford, England)
Reasons for Gratitude Amid the COVID-19 Pandemic
Posted on by Dr. Francis Collins
For many of us, Thanksgiving will feel really different this year. Less will need to be more, as we celebrate alone or with our immediate household members to stay safe and help combat the surge in COVID-19 cases across most of the land. And yet, times of trouble can also help us to focus on what’s really important in our lives. So, even as we face these challenges and the range of emotions that arise with them, it’s worth remembering that this Thanksgiving, there remain many reasons to be grateful.
I’m certainly grateful for a loving family and friends that provide depth and meaning to life, even though most of us can’t be physically together and hug each other right now. My faith is also a source of comfort and reassurance at this time. I also feel a deep sense of gratitude for everyone who has sacrificed for the common good over the last several months, especially those who’ve masked up and physically distanced to provide essential services in our communities to keep everything going. You will no doubt have your own list of heroes, but here are just a few of mine:
• Healthcare workers, thanks for all you do under such difficult and dangerous conditions.
• Essential workers, thanks for clocking in every day. That includes bus drivers, grocery store cashiers, waste collectors, tradespeople, firefighters, law enforcement officers, and all those who deliver packages to my door.
• Teachers, working remotely or in person. Thanks for your commitment to our students and continuing to bring out the best in them.
• Parents, including so many now working with kids at home. Thanks for juggling responsibilities and making everything work.
• Clinical trials participants. Your participation is critical for developing treatments and vaccines. Thanks to you all, including the fine examples of many public figures, including the trial participation of Senator Rob Portman and financial contribution of legendary performer Dolly Parton.
• Everyone following the 3 W’s: Wear a mask, Watch your distance, and Wash your hands. Thank you for doing your part every day to keep yourself, your loved ones, and your community safe. You are our front lines in the battle.
• Researchers, from both the public and private sectors, who are working in partnership all around the world. Our shared goal is to learn all we can about COVID-19 and to develop better tests, new treatments, and safe and effective vaccines.
On that note, you may have heard about the very promising interim clinical trial results of an investigational COVID-19 vaccine known as mRNA-1273, co-developed by the biotechnology company Moderna, Cambridge, MA, and NIH’s National Institute of Allergy and Infectious Diseases. That mRNA vaccine was found to be 94.5 percent effective in preventing symptomatic COVID-19. Another mRNA vaccine, developed by Pfizer and BioNTech, also recently was shown to be 95 percent effective and has now submitted an application for emergency use authorization (EUA) to the Food and Drug Administration (FDA). In addition, AstraZeneca announced that, in a late-stage clinical trial, the vaccine it developed in partnership with the University of Oxford reduced the risk of COVID-19 infection by an average of 70 percent, with up to 90 percent efficacy in one dosing regimen.
Other promising vaccine candidates continue to work their way through clinical trials, and we’ll no doubt be hearing more about those soon. It is truly remarkable to accomplish in 10 months what normally takes about 8 years. Therapeutic progress is also moving forward rapidly, with a second monoclonal antibody treatment for high-risk outpatients receiving emergency use authorization from the FDA just a few days ago.
For all of these advances, I am immensely grateful. Of course, it will take time and continued study to get a COVID-19 vaccine fully approved and distributed to all those who need it. The success of any vaccine also will hinge on people across the country—including you and all those whom I’ve recognized here—making the choice to protect themselves and others by getting vaccinated against COVID-19.
As we look ahead to that day when the COVID-19 pandemic is under control, I encourage you to take some time to jot down your own list of reasons to be grateful. Encourage family members to do the same and take some time to share them with one another, whether it’s around the table or by email, phone, or videoconferencing. The holidays are a time for making memories and—as different as it may look—this year is no different. So, while you’re enjoying your Thanksgiving meal around a smaller table, remember that you’re doing it from a place of love and gratitude. I wish for you a safe and happy Thanksgiving.
Links:
Coronavirus (COVID) (NIH)
Your Health: Holiday Celebrations and Small Gatherings (Centers for Disease Control and Prevention, Atlanta)
