COVID-19 Situation Report
Editor: Alyson Browett, MPH

Contributors: Clint Haines, MS; Noelle Huhn, MSPH; Natasha Kaushal, MSPH; Amanda Kobokovich, MPH; Christina Potter, MSPH; Matthew Shearer, MPH; Marc Trotochaud, MSPH; and, Rachel A. Vahey, MHS.
MONKEYPOX OUTBREAKS UPDATE Read our latest update from June 1 on the monkeypox outbreaks and visit our monkeypox resource page. We will continue to analyze the situation and provide updates, as needed. If you would like to receive these updates, please sign up here.
EPI UPDATE The WHO COVID-19 Dashboard reports 527.6 million cumulative cases and 6.29 million deaths worldwide as of June 1. The global weekly incidence decreased (-11.4%) over the previous week. The weekly trend increased in the Americas (+9.2%) and Eastern Mediterranean (+1.4%), while decreasing trends were observed in the remaining 4 regions. The trend in reported global weekly mortality decreased for an eighth consecutive week, but appears to be slowing, down 2.2% from the previous week. The number of new weekly deaths increased in the Americas (+13.2%), Western Pacific (+18.3%), and Africa (+15.2%). The number of new weekly deaths decreased in the other 3 regions.

The Omicron variant of concern (VOC) accounts for nearly all analyzed samples, with BA.2 responsible for 75% of these. Other Omicron sublineages are responsible for nearly all other cases, with BA.1 accounting for 4%, BA.2.12.1 for 16%, BA.4 for 3%, and BA.5 for 2%.

The US CDC is reporting 84.2 million cumulative cases of COVID-19 and 1,002,422 deaths. The current average daily incidence appears to have peaked, falling to a 7-day moving average of 103,686 on May 31, down from a high of 110,350 on May 26. However, the decline could be due to delayed reporting attributable to the Memorial Day holiday. The average daily incidence on Memorial Day (May 30) this year is 5 times higher than the average reported on last year’s Memorial Day (May 31, 2021). Prior to the holiday weekend, Our World In Data reported 7-day average US test positivity of 12%. The daily mortality dropped slightly to an average of 264 deaths per day*, and we have not yet observed an increase corresponding to the surge in daily incidence. Hospital admissions of people with COVID-19 continue to trend upwards, although more slowly, with an increase of 6% over the past week. New cases continue to be driven by the the BA.2.12.1 sublineage of Omicron (59%), followed by the BA.2 subvariant (35%) and B.1.1.529 (6%).
*Changes in state-level reporting may affect the accuracy of recently reported data, particularly over weekends. In an effort to reflect the longer-term trends, the numbers reported here may not correspond to the most recent dates.

WHO ESTIMATED GLOBAL EXCESS DEATHS Scientists working with the WHO have admitted to errors in the estimated global excess deaths associated with COVID-19, data first reported in the beginning of May. In a preprint revision, the researchers lowered Germany’s estimated COVID-related deaths by 37% and increased estimates for Sweden by 19%. The numbers are not yet corrected in the project website, a living model that researchers will continuously update. WHO experts said they are working to correct the inaccuracies and communicate the changes. 

PFIZER-BIONTECH EUA APPLICATION FOR UNDER-5 VACCINE On June 1, Pfizer-BioNTech completed their request to the US FDA for Emergency Use Authorization (EUA) of their SARS-CoV-2 vaccine for children ages 6 months through 4 years. A SARS-CoV-2 vaccine for this age group is greatly anticipated, as children have been more affected during the Omicron variant surges compared to past surges caused by other variants. The US FDA acknowledged receipt of Pfizer-BioNTech’s application and said its experts will be evaluating the data. The FDA’s Vaccines and Related Biological Products Advisory Committee (VRBPAC) is scheduled to review EUA requests for both the Pfizer-BioNTech 3-dose vaccine regimen for children under age 5 and the Moderna 2-dose vaccine regimen for children under age 6 on June 15.

The under-5 age group is the only in the US that remains ineligible for SARS-CoV-2 vaccination. However, parents remain divided on whether to jump at the opportunity to vaccinate their children once the option becomes available or wait. A Kaiser Family Foundation survey conducted in April found that 18% of parents would vaccinate their under-5 children as soon as the series becomes available, 11% would do so only if required, 38% would “wait and see,” and 27% indicated they would “definitely not” vaccinate their young children. 

US TRAVEL MASK MANDATE The US Department of Justice on May 31 asked the 11th US Circuit Court of Appeals to overturn an April decision by a federal judge that struck down the mandate requiring masks on public transportation and in transit stations. In that April decision, US District Judge Kathryn Kimball Mizelle argued that the mandate violates the Administrative Procedure Act and exceeds the US CDC’s statutory authority. However, the Justice Department argues in a 48-page brief that a mask mandate falls squarely within the CDC’s authority to protect public health and argues the District Court did not show the agency acted outside the “zone of reasonableness.”

In related travel news, White House officials met this week with travel industry officials who are pushing for the Biden administration to end a requirement that vaccinated international travelers test for SARS-CoV-2 prior to flying to the US. Industry officials argue that the pre-departure test requirement is not in line with the current threat from COVID-19 and that it is harming the US economy, as travelers are visiting other nations that have dropped their testing mandates. Some medical and public health experts also question the usefulness of pre-departure testing, arguing the disease is already circulating in the US.

HEALTH SYSTEMS STRENGTHENING Since the beginning of the COVID-19 pandemic, international organizations and national governments have focused on the public health emergency and set aside little funding aimed at strengthening healthcare systems, particularly in relation to pandemic preparedness. A proposed Financial Intermediary Fund (FIF) for Pandemic Prevention, Preparedness and Response, to be hosted by the World Bank, has received US$962 million in pledges, but it remains unclear how much of those or future commitments will go directly to national governments to fortify their public health infrastructure versus directly funding medical countermeasures. The comment period on a World Bank white paper on the proposed FIF closed yesterday, and feedback will be valuable in clarifying priorities for the fund. Without additional and sustained assistance from international and national sources, low- and middle-income countries likely will continue to struggle to purchase sufficient equipment and medicines, and pay for qualified staffing, in order to take care of patients today and prepare for the next pandemic. 
CHINA Following a surge in cases during March and April due to the Omicron variant of concern (VOC), the number of new COVID-19 cases in China has dropped significantly under the country’s stringent “zero COVID” strategy that employs widespread lockdowns, mass testing, and other mobility controls. In Shanghai, authorities are moving toward lifting strict lockdowns that have been in place for 2 months, heavily impacting the economy and, arguably, residents’ mental health. Though most residents are allowed to freely move about the city and return to work and school, COVID-19 restrictions continue to impact everyday life in the city, with residents needing to show negative PCR test results taken within the previous 72 hours to enter public spaces or access public transit. Officials hope that Shanghai’s reopening will quickly mobilize its manufacturing and export-heavy economy and help to correct a sharp economic slowdown. Beijing officials also announced restrictions in that city will be partially lifted, allowing people to return to work and resume shopping. While officials and state media laud the nation’s zero COVID policy, including a front-page feature in the People’s Daily declaring Shanghai’s victory over COVID-19, others cite mounting mental, social, and economic impacts on residents and question the policy’s endgame, with the looming threat of future lockdowns amid further outbreaks.

NORTH KOREA Last week, North Korean leader Kim Jong Un and other top officials discussed loosening tight COVID-19-related restrictions, maintaining that the nation’s first pandemic outbreak is receding. However, those claims are widely disputed, with the WHO stating that the situation likely is getting worse, not improving. The daily number of people reported as having fever has dropped from about 390,000 2 weeks ago to 96,000 today. The WHO has offered technical support and medical resources, including vaccines, on 3 separate occasions, but officials have declined those offers. Additionally, WHO officials have requested access to details about symptoms, transmission, and severity to better understand the nation’s situation, but have not yet received that information. North Korea’s claim to have controlled COVID-19 without vaccinations, lockdowns, or drugs raises many questions and concerns among experts, particularly because the outbreak there could have global implications. 

PAXLOVID Some healthcare providers are reconsidering prescribing Paxlovid to very low-risk individuals infected with SARS-CoV-2. The rationale is based on the potential for viral rebound, previously reported by the CDC, and that individuals who experience a rebound after completing isolation are more likely to transmit the virus to others before they are actually recovered. Therefore, some providers are choosing not to prescribe Paxlovid to individuals not meeting criteria for high-risk categories, instead hoping mild infections will run their course. Pfizer is currently reporting a rebound rate of about 2%. Still, the proportion could possibly be an underestimate, as there is low visibility on the true number of Paxlovid courses being prescribed and taken, and by which populations. Additionally, there is no central mechanism for people taking Paxlovid to report instances of adverse events or viral rebound. The US HHS Office of the Assistant Secretary for Preparedness & Response (ASPR) maintains a website tracking ordered and dispensed COVID-19 therapeutics among US states and territories, but there is no demographic data associated with the numbers. Prescribers appear amenable to continuing to prescribe Paxlovid to high-risk individuals, as the drug reduced the risk of hospitalization and death by about 90% in clinical trials. Notably, those data are based on the use of Paxlovid among only unvaccinated people who were never previously diagnosed with COVID-19, highlighting the need for data on the drug’s use among other populations, including those who were previously vaccinated, previously infected, or are at low-risk of disease progression.

TESTING & ISOLATION The US CDC recommends that people who test positive for COVID-19 isolate for a minimum of 5 days and follow that with 5 days of wearing a mask if they are asymptomatic or symptoms are resolving. However, some people continue to test positive on at-home rapid antigen tests 5, 10, even 13 days after their initial diagnosis, raising concerns they might remain infectious longer than the recommended isolation period. Experts are divided as to whether rapid tests should be used as a bellwether of infectiousness but agree that the tests are a useful tool in helping people recovering from COVID-19 assess whether they should engage in certain activities after day 10, such as attending large indoor gatherings or visiting with elderly or immunocompromised people. Overall, people with COVID-19 in the US should continue to follow CDC guidance to help prevent further transmission of the virus.

NIH TREATMENT GUIDELINES The US NIH updated its Coronavirus Disease 2019 (COVID-19) Treatment Guidelines on May 31. The updates include 4 new sections discussing the care of children critically ill with COVID-19 or multisystem inflammatory syndrome in children (MIS-C); new information informing treatments to prevent blood clots among patients with COVID-19; additional rationale in sections discussing critical care for adults with COVID-19; new information about the use of Evusheld (tixagevimab/cilgavimab) for pre-exposure prophylaxis among immunocompromised individuals; and other information. 

RESEARCH ROUNDUP The research roundup provides quick synopses of COVID-19-related research.

From BMJ, a living systematic review and network meta-analysis evaluating the effectiveness of heterologous and homologous SARS-CoV-2 vaccine regimens with and without boosters in preventing infection, hospitalization, and death. The researchers found that 3-dose mRNA vaccine regimens, regardless of being heterologous or homologous, are the most effective against asymptomatic and symptomatic infections with SARS-CoV-2 variants including Alpha, Delta, and Omicron. The effectiveness of 3-dose regimens against COVID-19-related mortality could not be determined.

From the European Heart Journal, a systematic review and meta-analysis of 158 observational studies from 49 countries on 6 continents looking at the effect of the COVID-19 pandemic on the care for and outcomes of cardiovascular (CV) diseases unrelated to SARS-CoV-2 infection. Overall, the pandemic severely disrupted CV-related care, with disparity in severity by country income classification. According to the researchers, the disruptions likely will have impacts well into the future, as the longer people wait for CV-related care, the more damage to the heart muscle, increasing the risk of adverse outcomes. 

From JAMA Internal Medicine, a retrospective cohort study showing that pulse oximeters overestimate blood oxygen levels among darker-skinned COVID-19 patients—including those who are Asian, Black, and Hispanic—compared with White COVID-19 patients, possibly leading to delays in treatment. The findings point to one possible reason COVID-19 mortality rates have been higher in US communities of color.

From The Lancet Global Health, a modeling study estimating the transmission dynamics of SARS-CoV-2 in the African region from the beginning of the pandemic through 2022. According to the model, only 1.4% of the region’s estimated 505.6 million SARS-CoV-2 infections were reported, and 35.3% of the region’s estimated 439,000 deaths were reported as COVID-19-related. While the number of estimated infections were similar in 2020 and 2021, 81% of the deaths were in 2021. The researchers estimate that SARS-CoV-2 infections will remain high throughout this year but deaths will be substantially reduced due to an estimated 52.3% of the region’s population having some SARS-CoV-2 immunity, mostly from previous infection.

From medRxiv, a preprint study examining the protection conferred by prior SARS-CoV-2 infection and vaccination during the Omicron wave within resident and staff populations. Even among individuals infected prior to or during the period of Delta predominance, a third dose of mRNA vaccine provided significantly more protection from infection with Omicron than the primary 2-dose series, suggesting booster doses should remain a priority even among populations with previous infection.

From medRxiv, a preprint study examining the effectiveness of the combination monoclonal antibody treatment Evusheld (tixagevimab/cilgavimab) as pre-exposure prophylaxis among adults who were immunocompromised or otherwise at high-risk of COVID-19 infection or severe disease. Compared with controls, treated individuals had lower incidences of COVID-19 infection, hospitalization, and all-cause mortality. 

From medRxiv, a preprint study estimating the prevalence of SARS-CoV-2 infection during the Omicron BA.2/BA.2.12.1 surge in relation to official case counts and assessing the uptake of SARS-CoV-2 antivirals in New York City adult residents. According to the researchers, official surveillance data vastly underestimated the true magnitude of the recent BA.2/BA.2.12.1 surge, by about 30-fold, and among those residents with COVID-19, 56% were unaware of the availability of the antiviral Paxlovid. 

From Nature Communications, a study evaluating the virus-neutralizing capacity against SARS-CoV-2 variants Alpha, Beta, Gamma, Delta, and Omicron among 62 pediatric patients who were hospitalized with severe COVID-19 or acute multisystem inflammatory syndrome (MIS-C) and 65 pediatric outpatients who had recovered from mild COVID-19 prior to the emergence of Omicron. The researchers found that children who were previously infected with SARS-CoV-2 or had MIS-C are not protected against Omicron, but children who had received a 2-dose vaccine regimen demonstrated high cross-neutralization against all variants, including Omicron. The findings support the need for vaccination of children.

From PLOS Medicine, the latest update to a living systematic review and meta-analysis of studies published through July 2021 showing that most SARS-CoV-2 infections are not persistently asymptomatic and those infections that were asymptomatic were less infectious than symptomatic infections. The researchers note that the true proportion of asymptomatic COVID-19 cases remains unknown. 

From PLOS ONE, a prospective cohort study conducted in 2 community COVID-19 screening centers to evaluate the diagnostic accuracy of non-invasive detection of SARS-CoV-2 infection by trained dogs compared with nasopharyngeal RT-PCR, saliva RT-PCR, and nasopharyngeal antigen testing. The overall sensitivity of canine olfactory detection was 97% and reached 100% in asymptomatic individuals compared to RT-PCR, while the specificity was 91% and 94% in asymptomatic individuals. For nasopharyngeal antigen testing, dog detection had higher sensitivity (97% vs 84%) but lower specificity (90% vs 97%). The study supports the use of dogs to quickly obtain results and could be used in the context of mass screening.

From PNAS, a large study drawing information from several datasets covering 92 regions on 6 continents to estimate the effect of mask wearing on SARS-CoV-2 transmission, adjusting for mobility and nonpharmaceutical interventions (NPIs). The researchers found that the mean observed level of mask wearing corresponds to a 19% decrease in the reproduction number R, showing mask wearing in community settings is associated with a notable reduction in transmission.