Editor: Alyson Browett, MPH
PANDEMIC VS ENDEMIC Even as the number of COVID-19 cases continue to reach record levels in some regions, those in the general public, members of the scientific community, and politicians are debating when the world can move on from the pandemic, arguments summarized as “pandemic vs endemic.” Some health officials from the US and Europe have recently expressed cautious optimism that their regions could be moving out of a pandemic state and into a period of endemic disease control, citing a different immunological landscape due to vaccination and previous infections, continued mitigation measures such as mask-wearing and testing, and newly available antiviral treatments. Other experts warn it is too soon to declare a pandemic endgame, saying global vaccination gaps and the threat of new, possibly more dangerous variants make predicting the pandemic’s path impossible. Still others are warning that endemicity does not mean COVID-19 becomes harmless, as other endemic diseases continue to cause substantial suffering and death. For example, HIV, malaria, and tuberculosis—all considered to be endemic in certain regions—continue to kill millions of people each year and, although relatively controlled in wealthy nations, linger in poorer, more vulnerable countries.
The surge of COVID-19 cases caused by the Omicron variant is beginning to recede in regions of the US hit first, but other areas of the nation continue to experience record numbers of hospitalizations and deaths, creating various pandemic scenarios nationwide. In Europe, Denmark lifted all of its remaining COVID-19 restrictions last week, the first country on the continent to do so, while other nations, such as the UK and Austria, also are relaxing their rules. Thailand on January 27 adopted guidelines outlining how COVID-19 could become an endemic disease, but officials said it likely will still be between 6 months to a year before the country reaches that point. Research from Malawi, supported by evidence from other countries, suggests that a very high prevalence of the population in several African nations have already been infected with SARS-CoV-2, providing high levels of natural immunity and possibly signaling endemicity. While it remains unclear how the pandemic will reach an end, scientists agree that there is a light at the end of the tunnel.
OMICRON BA.2 Only about 2 months from first being detected, the highly transmissible Omicron variant of the SARS-CoV-2 virus—the most common form of which is called BA.1—has become the predominant variant worldwide, accounting for nearly 99% of all sequenced cases as of the end of January. Scientists are now tracking a sublineage of the original Omicron variant known as BA.2, or “stealth Omicron,” as well as 2 other subvariants, BA.1.1529 and BA.3. A growing number of cases are being attributed to BA.2, including 82% of new cases in Denmark,* 9% in the UK, and 8% in the US. Though BA.2 appears to be even more transmissible than its cousin, according to a Danish study, vaccines remain effective—perhaps more so—against it than BA.1. The WHO has urged health agencies worldwide to begin investigating BA.2, and the US CDC last week said that while the subvariant is circulating at low levels in the country, there is no evidence it causes more severe disease than the BA.1 lineage.
In a study posted online last week on the preprint server bioRxiv, researchers describe unusual genetic mutations in Omicron’s BA.1 lineage and postulate that it likely evolved under unusual conditions, such as within the body of a person with a compromised immune system. The research—which suggests that Omicron developed over time and not in a stepwise fashion from the last variant, Delta—makes it clear that scientists are unable to predict how and where the next variant will evolve, nor whether it will be more transmissible or virulent. *This high percentage could be attributable to Denmark’s robust sequencing program.
MODERNA VACCINE APPROVAL The US FDA on January 31 granted full approval to Moderna’s SARS-CoV-2 vaccine for the prevention of COVID-19 in adults aged 18 and older, the second such vaccine to receive approval in the US. The vaccine, to be marketed under the brand name Spikevax, is administered as 2 shots given 28 days apart and is the same formulation that has been available under emergency use authorization (EUA) since December 2020. The mRNA vaccine remains available under EUA as a third primary series dose for adults with certain types of immunocompromise and as a single booster dose for adults who originally received the same or different SARS-CoV-2 vaccine. Moderna’s vaccine—which is already licensed in several other countries and regions, including Canada, Japan, Israel, UK, and the EU—is the company’s first FDA-approved product. The FDA is currently reviewing Moderna’s EUA application for authorization among teenagers ages 12 to 17.
Also on January 31, Novavax filed for authorization of its SARS-CoV-2 vaccine, NVX-CoV2373, which uses nanoparticles of the viral spike protein to elicit an immune response. According to the Associated Press, US regulators have urged Pfizer-BioNTech to apply for emergency authorization for a 2-dose regimen of their SARS-CoV-2 vaccine for children ages 6 months to 5 years while awaiting data on a 3-dose course. The companies’ vaccine, marketed as Comirnaty, was the first vaccine to receive FDA approval for people aged 16 years and older, and it is authorized for use among children aged 5 to 15 years.
PAXLOVID The European Medicines Agency (EMA) last week recommended Pfizer’s antiviral COVID-19 treatment Paxlovid for conditional marketing authorization. The European Commission will fast-track review the recommendation, and if approved, EU member states would be able to use the oral antiviral to treat adults with COVID-19 who are at risk of severe illness while they recover at home. Italy, Germany, and Belgium are among several European countries that have already purchased the drug.
VACCINE EFFECTIVENESS New findings from the UK Health Security Agency provide further evidence that booster doses of SARS-CoV-2 vaccines are critical for protection against the Omicron variant. Two doses of a vaccine provided 60% protection from death around 6 months after the last dose in individuals 50 years and older, but a booster dose raised the protective efficacy to 95% 2 weeks after receipt of the shot. Uptake of booster doses is increasing in Europe but only approximately 50% of adults have received one as of late January. Modeling of the Omicron variant surge in Europe predicts that current levels of booster vaccinations could reduce the number of hospital admissions by 500,000-800,000, with further reductions of another 300,000-500,000 admissions if all previously vaccinated people received boosters. The assessment from the European Centre for Disease Prevention and Control (ECDC) also warns that countries with low vaccination rates are expected to face significant pressures on their hospital systems. Vaccines and booster doses remain one of the best tools for protecting individuals against death and reducing pressure on chronically overworked hospital staff.
Recent evidence indicates that current vaccine designs are still capable of providing protection against the Omicron variant sublineage BA.2. Protection against symptomatic infection 25 weeks after a second dose of vaccine is only around 13%, but the protective efficacy jumps to 70% 2 weeks after a booster dose. The jump in protective efficacy against symptomatic disease further highlights the role that booster doses can play in mitigating the severity of disease during the pandemic. The evidence that BA.2 does not escape immunity more than the original Omicron variant is welcome news after the immune escape shift seen between Delta and Omicron. However, a preprint report from Denmark suggests that the BA.2 variant may be 1.5 times more infectious than Omicron.
AT-HOME SARS-COV-2 TESTS Only 2 weeks after launching COVIDtests.gov, a website for US residents to order SARS-CoV-2 tests through the US Postal Service, about 60 million households have requested the tests so far, according to White House officials. The orders leave enough tests for about 65 million more households—about 260 million tests of the US government’s initial order of 500 million. Reportedly, the government plans to order an additional 500 million tests to increase availability. The US has been criticized for not having federal guidance on how to use testing as a COVID-19 mitigation strategy. But even when given FDA-authorized test instructions, a substantial proportion of test users misinterpret negative results of at-home self-tests by not taking into account the implications of a high-risk, pretest exposure and ignoring federal self-quarantine recommendations, according to a study published on January 31 in JAMA Internal Medicine. The researchers suggest that pilot-tested decision science-based instructions might help to increase test takers’ understanding of results and the tests’ usefulness to public health.
ADDITIONAL DOSES FOR IMMUNOCOMPROMISED Public health agencies around the world continue work to determine the effectiveness of additional or booster SARS-CoV-2 mRNA vaccine doses for various populations, including healthcare workers, older adults, and people with compromised immune systems. A report published January 28 in the US CDC’s Morbidity and Mortality Weekly Report (MMWR) aimed to better understand the effects of a third mRNA vaccine dose in immunocompetent and immunocompromised individuals. In the study, a third dose increased vaccine effectiveness (VE) against COVID-19-associated hospitalization from 82% to 97% among individuals with healthy immune systems and from 69% to 88% among people with immunocompromise. The researchers concluded the results support recommendations for a third mRNA vaccine dose as part of a primary series for immunocompromised adults or as a booster dose among immunocompetent adults.
Third doses of both the Pfizer-BioNTech and Moderna vaccines are authorized in the US as part of a primary series for people with immunocompromise, and in October 2021, the CDC recommended certain immunocompromised individuals receive a fourth, or booster, dose 6 months after their third shot. But some immunocompromised people say pharmacies have turned them away for a fourth dose. Last week, the CDC was expected to reinforce its messaging regarding fourth doses for certain immunocompromised individuals in a conference call with pharmacies. An estimated 7 million people in the US live with compromised immune systems, such as those with HIV or those taking immunosuppressive treatments for cancer or following an organ transplant. The US NIH announced this week it plans to study antibody responses to additional vaccine doses among kidney and liver transplant recipients who have had 2 to 4 previous vaccine doses but who did not have a detectable immune response. The study also will examine whether a concurrent reduction in immunosuppressive medication impacts antibody response.
CANADIAN PROTEST Thousands of Canadian truckers and other protesters made their way to Ottawa on January 29 as part of a so-called “Freedom Convoy” to protest vaccine mandates and other public health measures implemented during the COVID-19 pandemic. The rally originated in British Columbia the week prior and consisted of trucks and their supporters driving across the country to the nation’s capital. The original goal of the rally was to protest a mandate put in place on January 15 that required all unvaccinated cross-border truckers to quarantine upon returning home, but the message has since shifted to a general condemnation of all public health interventions. Media reported that people and vehicles clogged the streets of Ottawa making noise and bringing the city to a standstill, but the rally was largely peaceful.
The “Freedom Convoy” rally has been shrouded in controversy since before the event. The Canadian Trucking Alliance (CTA) directly opposed the rally and urged the public to be aware that many of the individuals who are speaking out have no direct connection to the trucking industry. Canadian government officials and the CTA also claim that approximately 90% of the nation’s truckers are already vaccinated and that the individuals participating in the rally represent a fringe minority group. The controversy began heating up when a GoFundMe for the rally raised C$5.5 million (US$4.3 million) in a short time. GoFundMe froze the account for discussions with the organizers, and a former intelligence analyst stated that the speed and anonymity of the donations raised red flags. The analyst also said there is clear activity from foreign countries on the GoFundMe page. Additionally, there are reports that some protestors espouse anti-Semitic and racist views and waved Nazi flags during the rally, defecated in the streets, harassed staff at a local homeless shelter, and at least one protester danced on Canada’s Tomb of the Unknown Soldier. Some protestors called for an attack on the Canadian Parliament similar to the attack on the US Capitol on January 6, 2021. By midday on January 31, many of the protestors had left the area. Prime Minister Justin Trudeau—who is isolating at an undisclosed location after announcing this week he tested positive for COVID-19—said he would not be intimidated by the protestors. The rally notably garnered support from a former US president’s son, Donald Trump Jr., and a tech billionaire, Elon Musk.
COVID-19 MISINFORMATION The music streaming platform Spotify was in the spotlight over the weekend after Canadian music icon Neil Young criticized the service for hosting a podcast by comedian Joe Rogan, who has come under fire for spreading COVID-19 misinformation. Late last week, Young called for his music to be removed from Spotify in protest, and he was later joined by other legendary artists Joni Mitchell and Nils Lofgren. Other popular podcast hosts on Spotify, including Brene Brown and Prince Harry and Meghan Markle, expressed concerns over the platform’s handling of pandemic misinformation. The hashtags #CancelSpotify, #DeleteSpotify, and #ByeSpotify were trending on social media. Spotify removed Young’s music over the weekend, and Spotify Chief Executive Daniel Ek on January 30 published transparency rules, saying the streaming service would add advisories before any content that discusses the virus and link to Spotify’s COVID-19 hub. Rogan responded in a video posted to Instagram, saying he would interview doctors with different opinions right after he talks to “the controversial ones.” WHO Director-General Tedros Adhanom Ghebreyesus thanked Young on Twitter “for standing up against misinformation and inaccuracies around #COVID19 vaccination.”
Meanwhile, in an address to the International Catholic Media Consortium on COVID-19 Vaccines on January 28, Pope Francis said that spreading misinformation and fake news regarding COVID-19 and vaccines constitutes a violation of human rights. His comments were the second time in less than a month that he has addressed misleading information about COVID-19. Pope Francis called on journalists to help the public better understand scientific facts and address the spreading “infodemic.”