FDA.gov Coronavirus (COVID-19) Update: April 20, 2021 – FDA.gov

For Immediate Release:

The U.S. Food and Drug Administration today announced the following actions taken in its ongoing response effort to the COVID-19 pandemic:

  • Today, the FDA took steps to further facilitate the authorization of tests for pooling specimens from asymptomatic individuals in serial testing programs. The FDA issued a pooling and serial testing amendment for many molecular diagnostic COVID-19 tests that had received an emergency use authorization (EUA) for testing individual samples. The amendment requires test developers to submit a notification to the FDA with the information required by the amendment, including self-certifying that the applicable validation has been completed. It further supports the expansion of COVID-19 testing in schools, workplaces, communities, and other entities looking to establish serial testing programs for people without symptoms and with no known suspected exposure to COVID-19.
  • Testing updates:
    • As of today, 367 tests and sample collection devices are authorized by the FDA under emergency use authorizations (EUAs). These include 269 molecular tests and sample collection devices, 75 antibody and other immune response tests, and 23 antigen tests. There are 49 molecular authorizations and one antibody authorization that can be used with home-collected samples. There is one molecular prescription at-home test, two antigen prescription at-home tests, four over-the-counter (OTC) at-home antigen tests, and two OTC molecular tests.
    • The FDA has authorized 8 antigen tests and 2 molecular tests for serial screening programs. The FDA has also authorized 462 revisions to EUA authorizations.

Related Information

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Coronavirus (COVID-19) Update: April 20, 2021 | FDA – FDA.gov

For Immediate Release:

The U.S. Food and Drug Administration today announced the following actions taken in its ongoing response effort to the COVID-19 pandemic:

  • Today, the FDA took steps to further facilitate the authorization of tests for pooling specimens from asymptomatic individuals in serial testing programs. The FDA issued a pooling and serial testing amendment for many molecular diagnostic COVID-19 tests that had received an emergency use authorization (EUA) for testing individual samples. The amendment requires test developers to submit a notification to the FDA with the information required by the amendment, including self-certifying that the applicable validation has been completed. It further supports the expansion of COVID-19 testing in schools, workplaces, communities, and other entities looking to establish serial testing programs for people without symptoms and with no known suspected exposure to COVID-19.
  • Testing updates:
    • As of today, 367 tests and sample collection devices are authorized by the FDA under emergency use authorizations (EUAs). These include 269 molecular tests and sample collection devices, 75 antibody and other immune response tests, and 23 antigen tests. There are 49 molecular authorizations and one antibody authorization that can be used with home-collected samples. There is one molecular prescription at-home test, two antigen prescription at-home tests, four over-the-counter (OTC) at-home antigen tests, and two OTC molecular tests.
    • The FDA has authorized 8 antigen tests and 2 molecular tests for serial screening programs. The FDA has also authorized 462 revisions to EUA authorizations.

Related Information

###

Boilerplate

The FDA, an agency within the U.S. Department of Health and Human Services, protects the public health by assuring the safety, effectiveness, and security of human and veterinary drugs, vaccines and other biological products for human use, and medical devices. The agency also is responsible for the safety and security of our nation’s food supply, cosmetics, dietary supplements, products that give off electronic radiation, and for regulating tobacco products.


Inquiries

Consumer:
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State Department To Issue Travel Warnings Amid ‘Unprecedented’ COVID-19 Risks – NPR

The U.S. Department of State will add a slew of countries to its “Do Not Travel List” later this week because of coronavirus danger. Paul J. Richards/AFP via Getty Images hide caption

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Paul J. Richards/AFP via Getty Images

The U.S. Department of State will add a slew of countries to its “Do Not Travel List” later this week because of coronavirus danger.

Paul J. Richards/AFP via Getty Images

The U.S. State Department on Monday announced plans to expand travel advisories, urging U.S. citizens to stay home as the COVID-19 pandemic continues to pose “unprecedented risks” around the globe.

The updated travel guidelines are intended to curb visits “to approximately 80% of countries worldwide” which are currently experiencing dramatic spikes in cases, the department said in a statement. New guidance is expected be released later this week.

The latest recommendations come as the coronavirus “continues to pose unprecedented risks to travelers,” and the new guidelines “better reflect the Centers for Disease Control and Prevention’s science-based Travel Health Notices,” according to the notice.

The State Department added: “As always, we are closely monitoring conditions around the globe, and will regularly update our destination-specific advice to U.S. travelers as conditions evolve.”

As of Monday afternoon, the Johns Hopkins Coronavirus Resource Center reported 141,786,586 COVID-19 cases around the world. The United States has confirmed more cases than any other country in the world — 31,733,400 with India, Brazil, France, Russia, the United Kingdom, Turkey, Italy, Spain and Germany rounding out the top 10 spots. Meanwhile, global deaths have surpassed 3 million, according to the latest data.

French President Emmanuel Macron in March extended a nationwide lockdown through the end of April, citing new, faster-spreading variants of the coronavirus. He called it “an epidemic within the epidemic.”

As NPR reported, “In Brazil, deaths have topped 3,000 per day as the country is ravaged by the virus. Mexico has recorded more than 211,000 deaths. India has had more than 175,000 deaths and deaths in the United Kingdom have topped 127,000.”

More Than Half Of U.S. Adults Have Gotten At Least One COVID-19 Vaccine Dose – NPR

A nurse administers the Moderna COVID-19 vaccine at a Veterans Administration Long Beach Healthcare System pop-up vaccination site at the Dae Hueng Presbyterian Church on Saturday in Gardena, Calif. More than half of U.S. adults have now received at least one vaccine dose. Patrick T. Fallon/AFP via Getty Images hide caption

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Patrick T. Fallon/AFP via Getty Images

A nurse administers the Moderna COVID-19 vaccine at a Veterans Administration Long Beach Healthcare System pop-up vaccination site at the Dae Hueng Presbyterian Church on Saturday in Gardena, Calif. More than half of U.S. adults have now received at least one vaccine dose.

Patrick T. Fallon/AFP via Getty Images

After a year of grim milestones, Sunday marked a hopeful statistic in America’s fight against the coronavirus. According to the Centers for Disease Control and Prevention, more than half of all American adults have now gotten at least one vaccine dose.

After months of limited vaccine availability, every adult in the country will eligible to sign up for vaccination on Monday. The only remaining states still with certain adult age restrictions — Hawaii, Massachusetts, New Jersey, Oregon, Rhode Island and Vermont — will open vaccine registration to all people age 16 and older, meeting a federal deadline for all adults to be eligible set earlier this month.

About 130 million adults have gotten at least one vaccine dose, the CDC reported Sunday. And 84 million, or about a third of all adults, are fully vaccinated. (The CDC considers people “fully vaccinated” if they have received two doses of the Pfizer or Moderna vaccine, or one dose of the Johnson & Johnson vaccine.) The U.S. has one of the highest vaccination rates in the world.

Within the U.S., New Hampshire, Maine, Connecticut, Massachusetts and New Mexico report the highest percentage of population who have received at least one dose, according to NPR’s vaccination tracker.

Most of the states with the highest vaccination rates have historically voted Democratic in presidential elections, with the exception of South Dakota.

On the flip side, many of the states reporting the lowest rates of people receiving at least one dose of vaccine are traditionally Republican voting.

The vaccination trend is not absolute — it does not hold for the percentage of adults who are fully vaccinated, for example, where Republican Alaska leads.

Still, more than 40% of Republicans say they don’t want to get the vaccine, according to a Monmouth University poll released Wednesday. “Much of this reluctance is really ingrained in partisan identity,” said Patrick Murray, director of the independent Monmouth University Polling Institute.

Speaking to CNN’s State of the Union on Sunday, Dr. Anthony Fauci said he was frustrated by the partisan divide, which he believes is fueled by comments by Republican leaders like Ohio Rep. Jim Jordan, who accused Fauci last week of promoting pandemic guidelines that violate Americans’ freedoms.

“It is quite frustrating because the fact that one may not want to get vaccinated, in this case a disturbingly large proportion of Republicans, only actually works against where they want to be,” Fauci told CNN.

“On the one hand, they want to be relieved of the restrictions. But on the other hand, they don’t want to get vaccinated,” Fauci said. “It just almost doesn’t make any sense.”

There’s also been a disparity in vaccinations by gender. Close to 60% of people who have been vaccinated are women, compared to about 40% men, according to Kaiser Health News. “Women are more likely to seek preventive care in general,” reporter Laura Ungar told NPR’s Weekend Edition.

“Also, women are more likely to take on the role of arranging health care for the family,” she said. “So they may be more able to kind of navigate the health system.”

Coronavirus (COVID-19) Update: April 16, 2021 – FDA.gov

For Immediate Release:

The U.S. Food and Drug Administration today announced the following actions taken in its ongoing response effort to the COVID-19 pandemic:

  • As part of the FDA’s effort to protect consumers, the agency issued a warning letter jointly with the Federal Trade Commission to Trinity Natural Health & Pain Management, Inc. for selling an unapproved product with fraudulent COVID-19 claims. The company sells  “COVID-19 Formula” and misleadingly represents that it can mitigate, prevent, treat, diagnose or cure COVID-19 in people. The FDA requested that Trinity Natural Health & Pain Management, Inc. take immediate action to cease the sale of any unapproved and unauthorized products for the treatment or prevention of COVID-19. Consumers concerned about COVID-19 should consult with their health care provider.
  • On Tuesday, the FDA and Centers for Disease Control and Prevention (CDC) issued a Statement regarding the Janssen (Johnson & Johnson) COVID-19 Vaccine. Out of an abundance of caution, the FDA and CDC recommended a pause in the use of this vaccine while we review the data from six reported cases in the U.S. of a rare and severe type of blood clot in people who received the vaccine. This pause was recommended, in part, to ensure that the health care provider community is aware of the potential for these adverse events and can plan for proper recognition and management due to the unique treatment required with this type of blood clot. The FDA added three questions about the recommended pause in the use of this vaccine to the Janssen COVID-19 Frequently Asked Questions webpage; they include:
    • Why are the FDA and CDC recommending a pause in the use of the Janssen COVID-19 Vaccine?
    • If I received the Janssen COVID-19 Vaccine am I at risk for these adverse events?
    • What should health care providers look for in evaluating Janssen COVID-19 Vaccine recipients for these rare events?
  • The FDA updated one question, How many doses can be obtained from the multi-dose vials of Moderna COVID-19 Vaccine, to the Moderna COVID-19 Frequently Asked Questions webpage to address the number of doses in vials. This information is also reflected in the Letter Granting Moderna EUA Amendment and the Fact Sheet for Healthcare Providers Administering Vaccine: EUA of the Moderna COVID-19 Vaccine to Prevent COVID-19.
  • Testing updates:
    • As of today, 363 tests and sample collection devices are authorized by the FDA under emergency use authorizations (EUAs). These include 266 molecular tests and sample collection devices, 75 antibody and other immune response tests, and 22 antigen tests. There are 46 molecular authorizations and one antibody authorization that can be used with home-collected samples. There is one molecular prescription at-home test, two antigen prescription at-home tests, four over-the-counter (OTC) at-home antigen tests, and two OTC molecular tests.
    • The FDA has authorized 7 antigen tests and 2 molecular tests for serial screening programs. The FDA has also authorized 457 revisions to EUA authorizations.

Related Information

###

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The FDA, an agency within the U.S. Department of Health and Human Services, protects the public health by assuring the safety, effectiveness, and security of human and veterinary drugs, vaccines and other biological products for human use, and medical devices. The agency also is responsible for the safety and security of our nation’s food supply, cosmetics, dietary supplements, products that give off electronic radiation, and for regulating tobacco products.


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Consumer:
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FDA.gov Coronavirus (COVID-19) Update: April 16, 2021 – FDA.gov

For Immediate Release:

The U.S. Food and Drug Administration today announced the following actions taken in its ongoing response effort to the COVID-19 pandemic:

  • As part of the FDA’s effort to protect consumers, the agency issued a warning letter jointly with the Federal Trade Commission to Trinity Natural Health & Pain Management, Inc. for selling an unapproved product with fraudulent COVID-19 claims. The company sells  “COVID-19 Formula” and misleadingly represents that it can mitigate, prevent, treat, diagnose or cure COVID-19 in people. The FDA requested that Trinity Natural Health & Pain Management, Inc. take immediate action to cease the sale of any unapproved and unauthorized products for the treatment or prevention of COVID-19. Consumers concerned about COVID-19 should consult with their health care provider.
  • On Tuesday, the FDA and Centers for Disease Control and Prevention (CDC) issued a Statement regarding the Janssen (Johnson & Johnson) COVID-19 Vaccine. Out of an abundance of caution, the FDA and CDC recommended a pause in the use of this vaccine while we review the data from six reported cases in the U.S. of a rare and severe type of blood clot in people who received the vaccine. This pause was recommended, in part, to ensure that the health care provider community is aware of the potential for these adverse events and can plan for proper recognition and management due to the unique treatment required with this type of blood clot. The FDA added three questions about the recommended pause in the use of this vaccine to the Janssen COVID-19 Frequently Asked Questions webpage; they include:
    • Why are the FDA and CDC recommending a pause in the use of the Janssen COVID-19 Vaccine?
    • If I received the Janssen COVID-19 Vaccine am I at risk for these adverse events?
    • What should health care providers look for in evaluating Janssen COVID-19 Vaccine recipients for these rare events?
  • The FDA updated one question, How many doses can be obtained from the multi-dose vials of Moderna COVID-19 Vaccine, to the Moderna COVID-19 Frequently Asked Questions webpage to address the number of doses in vials. This information is also reflected in the Letter Granting Moderna EUA Amendment and the Fact Sheet for Healthcare Providers Administering Vaccine: EUA of the Moderna COVID-19 Vaccine to Prevent COVID-19.
  • Testing updates:
    • As of today, 363 tests and sample collection devices are authorized by the FDA under emergency use authorizations (EUAs). These include 266 molecular tests and sample collection devices, 75 antibody and other immune response tests, and 22 antigen tests. There are 46 molecular authorizations and one antibody authorization that can be used with home-collected samples. There is one molecular prescription at-home test, two antigen prescription at-home tests, four over-the-counter (OTC) at-home antigen tests, and two OTC molecular tests.
    • The FDA has authorized 7 antigen tests and 2 molecular tests for serial screening programs. The FDA has also authorized 457 revisions to EUA authorizations.

Related Information

###

Boilerplate

The FDA, an agency within the U.S. Department of Health and Human Services, protects the public health by assuring the safety, effectiveness, and security of human and veterinary drugs, vaccines and other biological products for human use, and medical devices. The agency also is responsible for the safety and security of our nation’s food supply, cosmetics, dietary supplements, products that give off electronic radiation, and for regulating tobacco products.


Inquiries

Consumer:
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Brazil COVID-19: ‘Humanitarian Crisis’ With More Than 3000 Deaths A Day – NPR

A health worker treats a COVID-19 patient at a field hospital in Ribeirao Pires, greater Sao Paulo area, on Tuesday. Andre Penner/AP hide caption

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Andre Penner/AP

A health worker treats a COVID-19 patient at a field hospital in Ribeirao Pires, greater Sao Paulo area, on Tuesday.

Andre Penner/AP

Health officials in Brazil say many hospitals are running dangerously short of sedatives and other crucial medications used for treating gravely ill COVID-19 patients.

They say some health services have already exhausted stocks of certain drugs, while others expect to do so within the next few days unless they receive fresh supplies.

The warning comes amid intense international concern over the spiraling pandemic in Brazil, where the average daily death toll has risen above 3,000, the highest in the world. To date, 365,444 people in the country have died of COVID-19, according to Brazil’s health ministry.

Brazil’s health crisis is being described as a “humanitarian catastrophe” by the international medical aid agency Doctors Without Borders (known by its French acronym, MSF), which has teams in parts of the country.

The “Brazilian authorities’ … refusal to adopt evidence-based public health measures has sent far too many to an early grave,” MSF’s international president Dr. Christos Christou said in a statement on Wednesday.

He said this has put Brazil in “a permanent state of mourning” and has caused “the near collapse of Brazil’s health system.”

The alarm over the lack of medicines is being raised, in particular, by the country’s richest and most populous state, São Paulo, which has so far registered almost one in four of Brazil’s total COVID-19 deaths.

São Paulo’s state government says its health services are facing “very serious” shortages, notably of muscle relaxants and sedatives needed for patients on respirators in intensive care units.

In a letter sent Tuesday to Brazil’s Health Ministry, the state issued an urgent appeal for fresh supplies and accused the ministry of ignoring nine recent requests.

The scale of the problem has been underscored by a survey conducted by an organization representing local health officials: This found that more than two thirds of the 3,126 municipal health services in São Paulo were completely out of muscle relaxants, while 961 had no sedatives.

Front-line medical staff are reportedly turning to less effective alternative drugs, yet there have also been Brazilian media accounts of patients being tied by their arms to their beds to prevent them reacting violently to intubation when they wake up.

One of the country’s leading news organizations, Folha de S. Paulo, recently published photographs and video of patients on respirators with their arms tied to the sides of their beds in a hospital in the northwestern city of Porto Velho.

Medicine shortages are adding to the already intense pressure on the country’s intensive care units, where often exhausted and depleted staff are struggling to cope with a second wave of the pandemic, propelled by new variants of the virus. In parts of the country, patients have died while waiting for ICU beds to become available, according to medical staff and victims’ families.

Overall occupancy rates for ICU beds have dropped slightly recently but remain critical in most of Brazil, according to a bulletin issued Wednesday by Fiocruz, a national health research institution. It said 16 of Brazil’s 26 states have ICU bed occupancy levels of 90% or above. In São Paulo, it was 86%.

Brazil’s Health Ministry has reportedly had significant problems buying anything close to sufficient quantities of medicines to cope with the surge in intensive care patients. It said Thursday that a large consignment of medicines donated by businesses was to be flown into the country in the coming hours, including sedatives, muscle relaxants and other drugs.

São Paulo has long been highly critical of the response to the pandemic by President Jair Bolsonaro, who has had four health ministers since the first coronavirus case was reported in Brazil early last year.

The state is far from alone.

Bolsonaro is facing ferocious criticism at home and abroad for scoffing at the threat of the virus, undermining social distancing and isolation measures, advocating unproven remedies, bungling the national vaccination program and discouraging people from being vaccinated.

The far-right president’s position has become still more uncomfortable following a decision by Brazil’s Supreme Court on Wednesday to give the go-ahead to a Senate inquiry into his government’s handling of the pandemic.

Bolsonaro has argued throughout that lockdowns and other pandemic restrictions inflict more economic and social misery than the virus itself. He fell back on that defense again Wednesday, with a vaguely worded warning that there will soon be “enormous crises” in Brazil.

“I am not threatening anyone, but Brazil is at the limit,” he told supporters, adding mysteriously: “I am waiting for the people to give a signal because the hunger, misery and unemployment is there.”

FDA Provides Guidance on Remote Interactive Evaluations for Oversight of Drug Facilities During COVID-19 – FDA.gov

For Immediate Release:

The following quote is attributed to Acting FDA Commissioner Janet Woodcock, M.D.

During this worldwide public health emergency, the FDA has used a variety of tools to oversee facilities that manufacture FDA-regulated products. These tools include record requests in advance of or in lieu of a drug facility inspection, relying on information from trusted regulatory partners, and remote interactive evaluations (such as remote livestreaming video of operations, teleconferences and screen sharing). We have used some or all of these approaches to evaluate facilities for human and animal medical products during the public health emergency when inspections of drug facilities were not possible due to travel or quarantine restrictions.

Inspections are an important tool to keep Americans safe, and are part of a set of tools used for regulatory oversight. As part of the wide variety of tools we have deployed during the COVID-19 pandemic, remote interactive evaluations have informed the FDA’s regulatory decision-making, contributed to ensuring drug quality and helped determine the scope, depth and timing of future inspections. By necessity, we have adapted by conducting more remote interactive evaluations throughout the public health emergency and are continuing to expand their use as appropriate. The purpose of this new guidance is to provide further clarity for regulated facilities on how the FDA will request and conduct these remote interactive evaluations during the COVID-19 public health emergency.

We recognize that remote interactive evaluations do not replace inspections, and that there are situations where only an inspection is appropriate based on risk and history of compliance with FDA regulations. Within the exceptional context of a global pandemic, we see remote interactive evaluations as part of a necessary strategy to evaluate medical product facilities by using all available approaches to ensure the medical products we regulate are safe, effective and of high quality.

Additional Information

  • Today, the U.S. Food and Drug Administration announced the availability of a guidance document entitled, “Remote Interactive Evaluations of Drug Manufacturing and Bioresearch Monitoring Facilities During the COVID-19 Public Health Emergency.” This guidance describes various interactive and virtual tools. The agency refers to its use of any combination of these interactive tools as a remote interactive evaluation. 
  • This guidance describes how remote interactive evaluations will be requested by the FDA and conducted for the duration of the COVID-19 public health emergency at any facility where pharmaceutical products, including biological products, are manufactured, processed, packed or held; facilities covered under the FDA’s bioresearch monitoring program; and outsourcing facilities registered under section 503B of the Federal Food, Drug, and Cosmetic Act.  
  • The agency will use existing risk management methods and related tools to determine when to request a facility’s participation in a remote interactive evaluation. The FDA conducts inspections for many purposes and programs, including pre-approval and pre-license, post-approval, surveillance, for-cause and bioresearch monitoring programs. The agency will consider each of these inspectional program areas as possible candidates for remote interactive evaluations, recognizing that there will be instances where only an inspection will be appropriate. 
  • The FDA intends to use information from remote interactive evaluations to meet user-fee commitments and to update facilities information, when deemed appropriate based on risk and history of compliance with FDA regulations. Facilities can choose to decline the FDA’s request to perform a remote facility evaluation; however, this may delay the agency’s ability to evaluate the facility or product and make a regulatory decision. The FDA will not accept requests from applicants or facilities to perform a remote interactive evaluation, as decisions to offer a remote interactive evaluation will rest with FDA, based on risk and compliance history.
     

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The FDA, an agency within the U.S. Department of Health and Human Services, protects the public health by assuring the safety, effectiveness, and security of human and veterinary drugs, vaccines and other biological products for human use, and medical devices. The agency also is responsible for the safety and security of our nation’s food supply, cosmetics, dietary supplements, products that give off electronic radiation, and for regulating tobacco products.


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FDA.gov Coronavirus (COVID-19) Update: April 13, 2021 – FDA.gov

Boilerplate

The FDA, an agency within the U.S. Department of Health and Human Services, protects the public health by assuring the safety, effectiveness, and security of human and veterinary drugs, vaccines and other biological products for human use, and medical devices. The agency also is responsible for the safety and security of our nation’s food supply, cosmetics, dietary supplements, products that give off electronic radiation, and for regulating tobacco products.

Previous COVID-19 may cut risk of reinfection 84% – CIDRAP

People who had COVID-19 had an 84% lower risk of becoming reinfected and a 93% lower risk of symptomatic infection during 7 months of follow-up, according to findings from a large, multicenter study published late last week in The Lancet.

The prospective cohort SARS-CoV-2 Immunity and Reinfection Evaluation (SIREN) study, by Public Health England Colindale researchers, involved 25,661 workers at public hospitals throughout England who were tested for SARS-CoV-2 every 2 to 4 weeks and antibodies at enrollment and every 4 weeks. Volunteers also completed questionnaires on symptoms and exposures every 2 weeks.

Of the 25,661 participants, 32.3% were assigned to the baseline positive (possibly or probably previously infected) group, and 67.7% were assigned to the negative group. Of the 8,278 positive participants, 91.2% had SARS-CoV-2 antibodies at study enrollment, while 7.0% were negative for antibodies but had a previously positive antibody and/or coronavirus test, and 1.8% had tested positive for COVID-19 but didn’t have linked antibody data.

Far fewer symptomatic infections

From June 2020 to January 2021, 1.4% of the 8,278 participants who previously had COVID-19 were infected, compared with 9.8% of 17,383 initially coronavirus-naïve participants. Infections in the baseline-positive group peaked in the first week of April, while they peaked in the negative group the last week of December.

Incidence density was 7.6 new infections per 100,000 person-days in those previously infected, versus 57.3 per 100,000 person-days in those without previous infection. Compared with primary infections, the adjusted incidence rate ratio was 0.16 for reinfections. Median time between primary infection and reinfection was more than 200 days.

Among the baseline-positive group, 50.3% of infections were symptomatic, with 32.3% involving usual coronavirus symptoms. Among the baseline-negative cohort, 80.3% of infections were symptomatic, 66.1% of them involving usual COVID-19 symptoms.

The authors noted that, late in the follow-up period, from Dec 8, 2020, to Jan 11, 2021, 52.2% of all participants were vaccinated against SARS-CoV-2. Thus, 0.4% of the study’s person-time follow-up included participants 21 or more days after vaccination, which the researchers said likely had only a modest effect on the results.

Median participant age in the baseline-positive cohort was 45.7 years, 84.2% were women, and 87.3% were White. Median follow-up was 275 days in the positive group and 195 days in the negative group.

“This study shows that previous infection with SARS-CoV-2 induces effective immunity to future infections in most individuals,” the authors wrote. “The importance of understanding the nature and rate of SARS-CoV-2 reinfection to guide non-pharmaceutical interventions and public health control measures is essential in this evolving pandemic.”

Natural immunity vs vaccine protection

In a commentary in the same journal, Florian Krammer, PhD, of the Icahn School of Medicine at Mount Sinai in New York City, said that although natural infection tends to induce lower and more variable antibody concentrations than COVID-19 vaccines, “the findings of the authors suggest that infection and the development of an antibody response provides protection similar to or even better than currently used SARS-CoV-2 vaccines.

He added, “The SIREN study adds to a growing number of studies, which demonstrate that infection does protect against reinfection, and probably in an antibody-dependent manner.”

Krammer pointed out that the researchers didn’t link quantitative antibody measurements to protection against infection afforded by natural infection versus vaccines, a topic that should be a priority for future studies.

“Establishment of antibody titres as a correlate of protection and defining a protective titre would be extremely important for public health considerations and for patient management,” he wrote. “A correlate of protection and a protective threshold would also allow for the development of additional SARS-CoV-2 vaccines based on small immunogenicity-based phase 3 trials rather than large and costly field efficacy trials, which are becoming exceedingly difficult to perform.”