COVID-19 Situation Report |
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Editor: Alyson Browett, MPH
Contributors: Clint Haines, MS; Natasha Kaushal, MSPH; Amanda Kobokovich, MPH; Christina Potter, MSPH; Matthew Shearer, MPH; Marc Trotochaud, MSPH; and, Rachel A. Vahey, MHS.
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PANDEMIC MILESTONE March 11 marked 2 years since the WHO named COVID-19 a pandemic. More than 6 million people—and possibly many more—have lost their lives to SARS-CoV-2, and more than 450 million people have been infected. Notably, the WHO first declared the novel coronavirus a public health emergency of international concern (PHEIC) on January 30, 2020—when there were no deaths outside of China—but global levels of concern did not rise until the agency characterized COVID-19 as a pandemic. At that time, there were more than 118,000 cases and 4,291 deaths in 114 countries. Now, 2 years and millions more deaths later, many wealthy nations are reopening, having benefited from high levels of vaccination coverage and access to diagnostics and treatments, while some middle- and low-income countries (LMICs) continue to endure pandemic-related restrictions with low vaccination coverage and limited-to-no access to tests and therapies. To be sure, the pandemic has laid bare—and in some cases worsened—healthcare inequities among and within nations.
As some of the world seemingly moves on from the pandemic, conditions in other areas remain ideal for new variants to emerge. In the past week, there are signs that some of the sharp declines in new COVID-19 cases due to the Omicron variant could be reversing; Europe and Africa experienced an increase in cases last week, while the Western Pacific region continues to chart record numbers. More than 130 world leaders, economists, humanitarians, scientists, celebrities, and others signed an open letter urging more action to quickly vaccinate people in LMICs and “do what is necessary” to end the pandemic. Even as countries make moves to return to a “new normal” and many SARS-CoV-2 vaccines continue to prove safe and effective at preventing severe disease and death, the pandemic is not over. The virus is impossible to predict, and a new variant could develop the ability to slip past the vaccine- or infection-induced immune protection that much of the world’s population now has. That means public health measures might need to be reinstated and additional vaccine booster doses—or new vaccine formulations that address multiple variants—could be recommended in the future to combat waning protection.
EUROPEAN UPSWING Several European countries—including Austria, Germany, Netherlands, and the UK—are experiencing upswings in COVID-19 case trends over the past week, following weeks of decline. France lifted most of its restrictions on March 14 but is already seeing an increase in cases. Some nations, including the Netherlands and the UK, also are seeing increases in COVID-related hospitalizations. Several factors could be causing the increasing trends, including behavior changes following the removal of mitigation measures or waning vaccination protection. The WHO warned on March 13 that the war in Ukraine, which has forced more than 3 million people to flee to neighboring countries, could worsen the pandemic in Europe. The agency is working to keep medical supplies moving into the region. Hungary, Romania, Slovakia, and Moldova are providing testing, treatment, and vaccines at no charge to Ukrainian refugees.
Other experts posit the Omicron variant of concern (VOC) sublineage BA.2 could be driving an increase in cases. In the UK, researchers with the REACT monitoring program estimate that as of February 21, nearly half (47.2%) of sequenced samples were the BA.2 subvariant. In their previous report from late January, less than 1% of the samples were BA.2. Analysis from the Wellcome Sanger Institute shows that in the week to March 4, BA.2 is responsible for more than 75% of new COVID-19 cases in the country, suggesting the subvariant is now predominant. Notably, the REACT surveillance program, as well as several other UK COVID studies, are losing funding and will cease operations at the end of March. Several experts criticized the moves as shortsighted, saying the recent uptick in cases could portend the beginning of a sixth wave of COVID-19 cases.
In the US, daily cases, hospitalizations, and deaths continue to decline, but some warn the nation—much of which has recently dropped public health measures—should take note. With lower rates of vaccination and booster coverage than many European countries, and the BA.2 sublineage believed to be more transmissible than BA.1, the US could face rising hospitalizations if a new surge develops. The US CDC estimates that BA.2 is now responsible for about 11.6% of new COVID-19 cases in the country as of March 5, up from about 1% at the end of January. Still other experts predict the rising percentage of cases caused by BA.2 should not be cause for alarm in the US, expressing doubt that the subvariant will cause a new surge. They cite the protective effects of vaccines and natural immunity and the effectiveness of some treatments against the Omicron subvariant.
Last week at a briefing, the WHO discussed another variant, AY.4/BA.1 recombinant, or so-called “Deltacron,” which has been detected in a small number of cases in France, Netherlands, Denmark, and the US. WHO officials noted that little is known about the recombinant variant, which combines attributes from the Delta and Omicron variants of concern, but said many studies are ongoing. Several experts outside of WHO said the variant should not be cause for concern at this time.
WASTEWATER SURVEILLANCE Wastewater disease surveillance, which can detect viral fragments shed in feces, has been used for decades to track infectious agents, from polio to norovirus, but the method has moved into the spotlight during the COVID-19 pandemic. The inexpensive method can help monitor infections, predict where outbreaks might occur, and, using the added step of genetic sequencing, provide clues about how SARS-CoV-2 is evolving. In Europe, 26 of the 27 EU Member States have established SARS-CoV-2 wastewater monitoring systems.
The US CDC last month launched a dashboard for its National Wastewater Surveillance System to track SARS-CoV-2 levels in sewage so communities can quickly adapt their public health responses. But with 400 sites in 34 states, focused mainly in areas of high population, and only a dozen states routinely reporting results, the US system has enormous gaps in what could otherwise be a robust monitoring program. Instead of working with local labs to help states stand up surveillance programs, the CDC contracted a large, private commercial lab to assist states. But privacy concerns, logistical challenges, and a lack of trust in the national company have hindered progress in expanding the system. A system with wider coverage would be able to give a more detailed picture of the current pandemic’s fluctuations and also serve as a monitoring system for future disease outbreaks. But some wastewater scientists expressed concern that without permanent and more thoughtful use of funding, wastewater surveillance may never be established in the US as a long-term tool for protecting public health.
US IMMIGRATION POLICIES Early in the COVID-19 pandemic, the US CDC issued an order under Title 42 suspending the right of certain asylum seekers to enter the US at any border crossing or port of entry in order to control the situation in congregate settings where noncitizens are processed and held. Children traveling alone were exempted from the order shortly after US President Joe Biden took office in January 2021. Over the weekend, the CDC terminated the order as it relates to unaccompanied minors after determining the “expulsion of unaccompanied noncitizen children is not warranted to protect the public health.” Testing and other preventive measures now allow these children to be released to sponsors in the US, typically close relatives. The change went into effect shortly before a court order would have forced the CDC to include, not exempt, children from Title 42. The order remains in effect for all other migrants.
However, pressure is mounting for the Biden administration to end the pandemic-related border restrictions for all noncitizen migrants. President Biden made a campaign promise to end what he called the “moral and national shame” of immigration policies put into place under former US President Donald Trump, but is now facing the reality of managing what could amount to record numbers of people seeking asylum in the coming weeks. Refugees from Ukraine are making their way to the US, and last week US Vice President Kamala Harris committed to taking in more asylum seekers from the country during an overseas trip. The same day, a Ukrainian family was barred from entering the country under Title 42. Although US immigration authorities later allowed the family to enter, the situation highlighted the order that some advocates call “absurd and untenable,” especially with the availability of COVID-19 diagnostics, vaccines, and therapies. The CDC has the authority to lift the order, which is set to expire in early April.
THIRD & FOURTH VACCINE DOSES Experts are beginning to look toward the future of preventing COVID-19 cases and hospitalizations, even as many areas of the world continue to recover from surges caused by the Omicron variant of concern. Among potential strategies under review is the need for third and fourth vaccine doses, particularly of mRNA vaccines. Studies are showing that a third dose of mRNA vaccine is needed to reach the same protective levels against Omicron compared to 2 doses for the Delta and Alpha variants. Many people in the US received their third, or booster, dose before and during the Omicron wave to demonstrated efficacy in keeping people out of the hospital; a recent CDC Morbidity and Mortality Weekly Report (MMWR) study showed that unvaccinated persons were hospitalized at a rate 23.0 times higher than boosted, vaccinated persons but at a rate only 5.3 times higher than unboosted, vaccinated persons. Notably, vaccine-derived immunity does wane over time, thus necessitating future doses in order to maintain protective levels. With this expected dip in mind, some are calling for a fourth dose of mRNA vaccines. Pfizer is already planning to submit data on fourth-dose efficacy to the US FDA. A small trial conducted in Israel found that a fourth dose restored immunity levels to where they had been with a third dose, although those levels also are expected to wane.
Nevertheless, many experts are highlighting the pitfalls in continually chasing the next dose of the same vaccine, especially in the context of future variants. For this reason, vaccine manufacturers are also looking at new formulations of vaccines to cover future variants and provide longer-lasting protection. Amidst its plans to submit for authorization of a fourth dose, Pfizer also has committed to developing a longer-lasting vaccine candidate that can cover more potential SARS-CoV-2 variants. The speed and efficacy of first generation SARS-CoV-2 vaccines was remarkable and a technological feat; now vaccine manufacturers must transition to a long-term outlook for maintaining protection against SARS-CoV-2.
CHINA China is facing its largest COVID-19 outbreak since the early days of the pandemic. On March 15, the National Health Commission reported the detection of 3,507 new cases due to community transmission, more than double the 1,337 recorded in the previous 24 hours. At least 15,000 cases have been recorded in recent outbreaks in 28 provinces, with about 80% of cases caused by the highly transmissible Omicron variant. A little more than half of those testing positive are asymptomatic, and no new deaths have been reported. Authorities attribute the large proportion of asymptomatic and less serious cases to the country’s high vaccination rate, which is estimated to be about 87%.
Although the total number of cases is low compared with some other nations, China continues to enforce its “dynamic zero-COVID” approach. In response, China has locked down tens of millions of people in several neighborhoods and cities, including Jilin, where most of the new infections have occurred, and Shenzhen, the nation’s technology hub. The shutdowns are impacting car and tech manufacturing and likely will further disrupt global supply chains. Notably, Shenzhen, in Guangdong Province, shares a border with Hong Kong, which also is experiencing an Omicron-fueled surge in cases. Additionally, Jilin province shares a long border with North Korea, which continues to claim it has recorded no COVID-19 cases. The quick surge is expected to overwhelm healthcare facilities and hospitals, particularly in rural areas, and the country has moved quickly to construct temporary facilities to house thousands of people who test positive. A forecasting model run by Lanzhou University predicted the current surge of infections will be brought under control in early April, racking up about 35,000 cases. However, if the current exponential rise in daily case numbers continues, many more cases will be recorded. The current outbreak is testing China’s costly zero tolerance approach in the face of the highly infectious Omicron variant, but there is no sign the nation will pivot to a “living with the virus” mentality anytime soon, despite deep economic disruption.
About 70% of assisted-living homes are experiencing outbreaks, and thousands of older adults have died of COVID-19. Hong Kong is working to maintain its “zero COVID” strategy of mass testing, contact tracing, border closures, and quarantines that kept SARS-CoV-2 at bay for the past 2 years. Nearly 300,000 of Hong Kong’s 7.4 million residents are isolating at home, and many have left the city to avoid compulsory testing, travel bans, and quarantines. Those who test positive on a rapid test—including those with mild or no symptoms—can be prosecuted if they refuse to enter a government-run quarantine center, unless the facilities are full. The government is working to construct additional isolation centers out of shipping containers. Some experts warn the initially successful “zero COVID” policy might have bred complacency, leading some people to forgo vaccination and catching the government off guard for the arrival of Omicron. Hong Kong’s situation also highlights the importance of vaccination in helping to prevent widespread disruption and protect people from hospitalization and death.
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