COVID-19
Updates on the COVID-19 pandemic from the Johns Hopkins Center for Health Security.

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The Johns Hopkins Center for Health Security also produces US Travel Industry and Retail Supply Chain Updates that provide a summary of major issues and events impacting the US travel industry and retail supply chain. You can access them here.
We will not publish a COVID-19 update on New Year's Day. Our next briefing will be on Tuesday, January 5.

We hope you, your friends, and your family have a safe and healthy holiday season.
From the first reports of unidentified pneumonia in China, our team at the Johns Hopkins Center for Health Security has been following and analyzing this situation closely. Thank you for reading our COVID-19 situation reports and learning alongside us. We are grateful to our technical team, who pulls together these updates with diligence and rigor—Divya Hosangadi, Amanda Kobokovich, Elena Martin, Christina Potter, Matthew Shearer, Marc Trotochaud, Rachel Vahey, and Matthew Watson; led by Dr. Caitlin Rivers—as well as our communications team, Margaret Miller and Julia Cizek. Finally, thank you to our funders and donors, who make these reports and the rest of our response work possible. 
In late December 2019, the initial reports emerged about 27 cases of an unidentified viral pneumonia in Wuhan, China. At that time, nobody imagined that 12 months later, the WHO would report 80 million cases and 1.8 million deaths worldwide.

In July, we took a look back at the first 6 months of COVID-19 and generated a timeline and overview to highlight some of the major events, benchmarks, and themes. At times over the past year, it has felt like we faced the same issues day after day without moving forward, and in some instances, we seemed to face the same challenges repeatedly. However, we as a global community have made a lot of progress in critical areas over the past 6 months, including numerous advancements in testing and vaccines. We are far from the end of this global disaster, and there is considerable disruption, pain, and work remaining; however, it now feels like there is finally a light at the end of the tunnel. 

Below, we have compiled a timeline of select events from the past 6 months of the pandemic:

July 7: Brazilian President Jair Bolsonaro tests positive for SARS-CoV-2
July 17: India surpasses 1 million cumulative cases
July 20: The WHO reports 600,000 cumulative deaths globally
July 22: China initiates vaccination of essential workers under an emergency authorization
July 23: The WHO reports 15 million cumulative cases globally
July 24: The US summer surge peaks at 67,187 new cases per day
July 28: The US surpasses Brazil as #1 globally in terms of daily mortality
July 29: The US surpasses 150,000 cumulative deaths

August 6: India surpasses the US as #1 globally in terms of daily incidence
August 7: 700,000 global deaths
August 9: The US surpasses 5 million cumulative cases
August 9: New Zealand reports 100 consecutive days without a documented case of domestic transmission
August 10: Brazil surpasses 100,000 cumulative deaths
August 12: 20 million global cases
August 15: South America’s first surge peaks at 75,932 new cases per day
August 22: Brazil surpasses the US to regain #1 globally in terms of daily mortality
August 23: 800,000 global deaths
August 26: India surpasses Brazil as #1 globally in terms of daily mortality

September 1: Russia surpasses 1 million cumulative cases
September 10: 900,000 global deaths
September 16: India surpasses 5 million cases
September 18: 30 million global cases
September 22: The US surpasses 200,000 deaths
September 29: 1 million global deaths

October 1: US President Donald Trump tests positive for SARS-CoV-2
October 3: India surpasses 100,000 cumulative deaths
October 4: The Great Barrington Declaration is published, calling for policies to achieve “herd immunity” through natural infection
October 9: Brazil surpasses 5 million cases
October 19: 40 million global cases
October 19: Spain surpasses 1 million cumulative cases
October 20: The US surpasses India to regain #1 globally in terms of daily incidence
October 21: Argentina surpasses 1 million cumulative cases
October 21: the US surpasses India to regain #1 globally in terms of daily mortality
October 24: France surpasses 1 million cumulative cases
October 26: Colombia surpasses 1 million cumulative cases
October 29: The WHO reports more than 500,000 new cases in a single day for the first time
October 30: The US becomes the first country to report more than 100,000 new cases in a single day

November 1: The United Kingdom surpasses 1 million cumulative cases
November 8: 1.25 million global deaths
November 8: Europe’s “second wave” peaks at 287,101 new cases per day
November 9: 50 million global cases
November 9: The US surpasses 10 million cases
November 12: Italy surpasses 1 million cumulative cases
November 16: Mexico surpasses 1 million cumulative cases
November 17: The US FDA issues an Emergency Use Authorization (EUA) for the first fully at-home SARS-CoV-2 test kit
November 18: Pfizer announces the completion of the Phase 3 clinical trials for its SARS-CoV-2 vaccine, developed in collaboration with BioNTech
November 21: Mexico surpasses 100,000 cumulative deaths
November 26: 60 million global cases
November 27: Germany surpasses 1 million cumulative cases
November 30: Moderna announces the completion of the Phase 3 clinical trials for its SARS-CoV-2 vaccine

December 2: The UK issues emergency authorization for the Pfizer/BioNTech vaccine
December 3: Poland surpasses 1 million cumulative cases
December 3: The US becomes the first country to report more than 200,000 new cases in a single day
December 4: Iran surpasses 1 million cumulative cases
December 4: 1.50 million global deaths
December 5: Russia opens vaccination to the public, using its Sputnik V vaccine
December 8: The US surpasses 15 million cases
December 8: The UK administers its first vaccinations to the public, using the Pfizer/BioNTech vaccine
December 10: Turkey surpasses 1 million cumulative cases*
December 11: US FDA issues an EUA for the Pfizer/BioNTech SARS-CoV-2 vaccine
December 13: 70 million global cases
December 14: The US surpasses 300,000 deaths
December 14: The US administers its first vaccinations to the public, using the Pfizer/BioNTech vaccine
December 15: The US FDA issues an EUA for the first fully at-home SARS-CoV-2 diagnostic test available without a prescription
December 17: French President Emmanuel Macron tests positive for SARS-CoV-2
December 18: US FDA issues an EUA for the Moderna SARS-CoV-2 vaccine
December 19: India surpasses 10 million cases
December 21: The first COVID-19 cases are reported in Antarctica, the last of the 7 continents to report a case
December 23: The US reports 1 million vaccine doses administered
December 24: Peru surpasses 1 million cumulative cases
December 24: Ukraine surpasses 1 million cumulative cases
December 26: European countries administer the first vaccinations to the public, using the Pfizer/BioNTech vaccine
December 27: 1.75 million global deaths
December 29: The UK begins administering the the second doses of the Pfizer/BioNTech vaccine

NOTE: The dates corresponding to incidence or mortality milestones, with the exception of the US, refer to the WHO COVID-19 dashboard. Individual country COVID-19 reporting pages are linked, but not all include historical data. US dates refer to US CDC reporting.
*Turkey updated its COVID-19 reporting to include all individuals who tested positive and reported more than 800,000 previously unreported cases on December 10. The incidence reported by the WHO does not align directly with this timeline.

The first 6 months of the pandemic were dominated by news of COVID-19 spreading to new continents and countries and national, state, and local governments implementing highly restrictive measures to prevent the introduction of the virus or bring national epidemics under control. However, the second half of 2020 had a very different storyline. Much of the global attention over the past 6 months was divided between progress in developing and testing various medical countermeasures and adapting COVID-19 control measures to ease the economic and social impacts of the pandemic while still slowing the spread. And while the main focus remains on identifying and tracking new cases and providing clinical care for active patients, attention is shifting toward recovery, whether in terms of patients recovering from the disease or societies and economies recovering from the pandemic.

EPIDEMIOLOGY & CONTROL MEASURES
The pandemic and the associated policies needed to curb transmission had a wide range of severe downstream impacts, wreaking havoc on national, regional, and local economies. The entertainment, service, and travel and tourism sectors bore the large brunt of the financial losses, and an unimaginable number of businesses around the world have closed, temporarily or permanently, and countless individuals were forced out of work. This has resulted in the loss of hundreds of millions of jobs and trillions of dollars in income globally. Additionally, tax revenue from businesses fell sharply, decreasing government revenue at a time when they need to increase spending in order to implement response operations and provide emergency financial support to individuals and businesses. Even healthcare systems have faced significant financial challenges, as many hospitals and health systems pared back non-essential or non-emergent procedures and patients delayed screenings and procedures due to concerns about infection risk.

In an effort to mitigate these economic losses, national, state, and local governments around the world eased COVID-19 restrictions once transmission decreased—or in some instances, regardless of the current transmission risk—which allowed individuals to resume some social and economic activities. The speed and degree to which these policies were relaxed varied by location, but it appeared that many governments erred on the side of supporting economic recovery over maintaining control of transmission. The increased social interaction provided opportunity for individuals, particularly those with mild or no symptoms, to transmit the infection in community settings, which inevitably led to increased incidence, hospitalizations, and mortality. As a result, many countries faced a resurgence in SARS-CoV-2 transmission, in many cases more severe than the first wave or surge. But unlike during the “first wave” of transmission, many governments were reluctant to reinstate highly restrictive COVID-19 policies when incidence increased—in some instances, higher than the initial surge—which permitted community transmission to continue and accelerate, often setting new records for daily incidence and mortality.

While each country’s epidemic is unique, this trend was evident in countries around the world, in virtually every region. Perhaps the most notable were European countries and the US due to the magnitude of their respective epidemics. In Europe, most countries—including France, Germany, Italy, Spain, and the UK, all of which were severely affected early in the pandemic—were able to bring daily incidence to very low levels and maintain them for several weeks or months. Following efforts to relax travel restrictions and social distancing measures in order to revive local and national economies, particularly those reliant on tourism, European countries soon faced increasing incidence. But rather than reimpose highly restrictive control measures like they did earlier in the pandemic, most countries elected to use modified or relaxed social distancing policies in order to maintain some level of economic activity, which resulted in continued transmission that eventually grew into a much larger “second wave” across the continent. In contrast to Europe, the US never really gained control of its “first wave” before state governments began to relax COVID-19 control measures. Many of these efforts occurred in states that were not severely affected during the initial surge, and the increase in social activity coincided with geographic spread of the US epidemic across the country. Daily incidence in the US decreased approximately 40% from its initial peak—down to approximately 19,000 new cases per day—before it rebounded, reaching 66,000 per day during the summer surge and more than 220,000 during the ongoing autumn/winter surge.

Similar trends are evident in a number of countries in other parts of the world as well, many of which were severely affected early in the pandemic. Other notable examples include Japan and South Korea, both of which gained control of transmission following their first wave before easing restrictions and facing larger second and/or third waves. Russia exhibited a trajectory similar to that of the US, decreasing transmission to about half of its first peak before facing a much larger second surge.

While much of the world continues to struggle with the pandemic, a number of countries and territories have demonstrated the ability to contain SARS-CoV-2 transmission. Most notable is New Zealand, which successfully interrupted domestic transmission in June and reported zero new domestic cases for more than 100 consecutive days. Following an outbreak in Auckland in August and September, which was brought under control relatively quickly, New Zealand has maintained daily incidence below 10 new cases per day. As an island nation, New Zealand has the advantage of being able to more tightly control inbound travel compared to most countries, implementing strict limitations on arriving travelers and mandating quarantine for those permitted to enter the country; however, the country’s strict adherence to evidence-based policies has helped it maintain control over its epidemic. After bringing domestic transmission under control through a tiered system of national-level “lockdowns,” New Zealand was able to relax the vast majority of restrictions, which allowed the country to resume most normal social and economic activities without resulting in dramatic increases in transmission. National officials continually evaluated epidemiological data and reintroduced control measures as necessary in response to emerging outbreaks or other incidents, enabling the country to quickly regain control and then slowly ease restrictions again.

Other examples of success include Australia, Brunei, Cambodia, China, Singapore, Taiwan, and Vietnam as well as many countries in Africa. Many experts around the world originally forecast that African nations would face major COVID-19 epidemics, due in part to weak health systems, limited testing and reporting capacity, and few government resources to support response activities, but this has largely not come to fruition. With a few exceptions, including Egypt and South Africa, African nations have generally maintained low levels of reported incidence since the onset of the pandemic. National leaders in many African countries were quick to implement social distancing restrictions, which helped contain community transmission. While African countries have been successful in terms of limiting transmission, many expect to face significant barriers to accessing SARS-CoV-2 vaccines as they become available.

While cases in the areas most severely affected early in the pandemic skewed heavily toward older, more vulnerable individuals, transmission during subsequent waves and surges tended to begin among younger adults. Limited testing capacity early in the pandemic necessitated allocating the available tests to those who sought care for their disease and those at the highest risk for progressing to severe disease, which included a high proportion of older adults. Younger individuals typically experience milder disease than older or high-risk patients; however, these milder symptoms (including asymptomatic infection) allow individuals to unknowingly continue social activities or essential work while infectious, which provides further opportunity to spread the disease. 

A number of people, including elected officials, have called for younger, healthier adults to continue social activity while protecting the most vulnerable. They viewed this as a way to spread the infection widely among those at the lowest risk for severe disease and death, with the goal of moving toward “herd immunity” that would, in turn, protect the most vulnerable. One notable example was the Great Barrington Declaration, which encouraged lower-risk individuals to “resume life as normal.” Experts around the world, spanning health care and public health, criticized this strategy as “scientifically and ethically problematic.” In addition to placing younger adults at risk, including for both acute COVID-19 disease and a variety of potential longer-term health effects, increased community transmission would inevitably spill over to high-risk settings, even if they were largely separated from the community. In response to the Barrington Declaration, experts published several high-profile responses, including the John Snow Memorandum, outlining the many shortcomings of approaches that aim to achieve herd immunity through natural infection. As most experts expected, increasing incidence in countries around the world tended to be followed several weeks later by increasing mortality, resulting from both mortality among the younger, healthier population who were driving community transmission and the spread from these individuals to higher-risk individuals, even those who remained relatively isolated.

LONG-TERM HEALTH EFFECTS
The global COVID-19 response has understandably focused heavily on combating community transmission and treating acute disease, but as more COVID-19 patients recover, evidence increasingly illustrates the longer-term health effects stemming from SARS-CoV-2 infection. Now colloquially referred to as “long COVID”—and affected individuals as “long-haulers”—persistent symptoms associated with SARS-CoV-2 infection have been reported in recovered individuals for months after recovery from acute infection or disease. The symptoms vary widely in terms of affected organ systems, duration, and severity, which poses challenges in identifying and classifying the longer-term condition. Difficulty breathing and fatigue are among the most commonly reported symptoms, but some recovered COVID-19 patients also report gastrointestinal distress; joint and muscle pain; cardiovascular effects, such as erratic heartbeat; and neurological symptoms, including light sensitivity, memory loss, and “brain fog.” The longer-term symptoms have been documented in individuals across the spectrum of acute COVID-19 disease severity as well as those who did not report symptoms during the acute stage of their infection, and individuals who were younger and healthier prior to infection (ie, those who would be expected to be at lower risk for severe COVID-19 disease and death) have also reported lasting effects from SARS-CoV-2 infection. The impact on lower-risk individuals is concerning, particularly as the age distribution of reported COVID-19 cases continues to shift toward younger portions of the population, and the diverse clinical presentation can make it difficult for clinicians to identify “long COVID,” particularly in patients that did not previously experience acute COVID-19 disease or test positive for SARS-CoV-2 infection.

Attention on the long-term health effects of COVID-19 is growing, but much uncertainty remains. Numerous research efforts are ongoing to better characterize the various health conditions affecting recovered COVID-19 patients, and it is becoming more clear that the COVID-19 pandemic could have effects that last beyond the completion of vaccination efforts.

VACCINES
While progress has been made on many fronts relative to medical countermeasures, the most important news pertains to vaccine development. Since the onset of the pandemic, vaccine development efforts around the world have yielded dozens of candidate products, currently in various phases of development, trials, and authorization. Russia initiated vaccination of the public in Moscow on December 5, using its Sputnik V vaccine, which is still undergoing Phase 3 clinical trials. China has developed multiple candidate vaccines, which are also at various stages of development and testing. The vaccine developed by Sinopharm is still completing Phase 3 clinical trials, but Bahrain and the United Arab Emirates authorized the vaccine for use. Doses of the Sinopharm vaccine have already been distributed to other countries as well. Several Chinese vaccines were issued emergency authorizations in China early in the clinical trial process, and vaccinations began for essential workers in July, despite not having Phase 3 clinical trial data available.

Perhaps the biggest news is the formal regulatory authorization of multiple vaccines in the UK, US, Canada, Europe, and numerous other countries. Following announcements of Phase 3 clinical trial results for the vaccines developed by Pfizer/BioNTech and Moderna, regulatory agencies began convening to review safety and efficacy data and determine whether the products warranted emergency authorization for use among the general public. On December 2, the UK was the first to authorize the use of a vaccine that had completed Phase 3 clinical trials, the product developed by Pfizer and BioNTech, and it initiated vaccination efforts on December 8. The US soon followed, with Emergency Use Authorizations (EUAs) for both the Pfizer/BioNTech vaccine (December 11) and the Moderna vaccine (December 18), and it began vaccinating individuals on December 14. European countries initiated their vaccination programs starting December 26. In the UK, the US, and Europe, the first vaccinations were administered to high-risk older adults, including long-term care facility residents, and frontline healthcare workers. Eligibility will expand as vaccine availability in each country increases. Phase 3 clinical trial data have not yet been released for the vaccines developed in China or Russia or for the AstraZeneca/Oxford University vaccine, another leading candidate. A number of other candidate vaccines developed in countries around the world are spread across the research and development pipeline, and work will continue on those products as vaccination efforts begin with those that have already received authorization from regulatory agencies.

But just having a vaccine will not end this pandemic. Production, logistics, and vaccination operations will be critical over the coming months and years, and everyone must remain vigilant and dedicated in order to combat the virus until we are able to deploy the vaccine globally. While vaccination has commenced in a number of high-income countries, principally in Europe and North America, many countries do not yet have access to any vaccines. It could be months before they receive their first doses, and it could take years to complete a global mass vaccination effort. Most low- and middle-income countries cannot compete financially against high-income countries, which puts them at a disadvantage in terms of securing vaccine doses as production is scaled up. Many low- and middle-income countries, including in Africa, have banded together under the WHO’s COVID-19 Vaccine Global Access Facility (COVAX), in partnership with Gavi and UNICEF, to pool funding—including donations from other countries and organizations—to support the purchase of early vaccine doses. As of December 18, 92 countries are eligible to receive vaccines under COVAX, and the WHO anticipates being able to distribute 1.3 billion doses of the vaccine in 2021, enough to cover 20% of the population in eligible countries.

In addition to production and allocation concerns, a number of questions remain about the vaccines’ impact. While efficacy has been demonstrated in Phase 3 clinical trials for 2 vaccines, it remains unclear how long the immunity conferred by the vaccines will last. Further, the vaccines have largely been trialed in adults, and additional data are required to assess their safety and efficacy in children. And while the vaccines have been shown to be efficacious in terms of preventing COVID-19 disease, including severe disease, researchers are still evaluating whether they are capable of preventing infection or mitigating the ability of vaccinated individuals to transmit the infection to others. As these questions and others are evaluated over the coming months and years, social distancing, mask use, and other COVID-19 risk mitigation measures will be critical to containing transmission.

Wear your mask, maintain physical distance, wash your hands, and stay home when you are sick. And remember, we are all in this together, even if we are 6 feet apart.