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Dr. Wilbur Chen, MD, MS, FACP, FIDSA, Professor of Medicine, 网红爆料 School of Medicine, and member of Governor's COVID-19 Taskforce

Today I want to summarize the global situation for the pandemic.

The total worldwide count of cases now exceeds 80 million, of which nearly 1.8 million deaths are attributed. These numbers are likely to be an undercount, as many cases and some deaths are missed.  The top 4 nations with the highest deaths due to COVID-19 are the United States (> 332 thousand), Brazil (>191 thousand), Russia (> 186 thousand), and India (>148 thousand).  The daily new cases and deaths are not slowing down at the moment. Recent or planned gatherings of friends and families during these winter holidays will result in new transmissions of the virus and cause new cases which will not be evident until 2 weeks from now.  So, this speaks to the importance of maintaining respectful distancing during the season (better to not arrange for gatherings outside your home), masking when outside the home, and hand hygiene.

Today (December 30, 2020), the U.K. equivalent of the U.S. Food and Drug Administration (FDA), known as the Medicines and Healthcare products Regulatory Agency (MHRA), announced the approval of a third COVID-19 vaccine; it is a vaccine manufactured by AstraZeneca in collaboration with Oxford University. The AstraZeneca vaccine is a virus-vectored vaccine, meaning that a weakened non-COVID-19 virus was modified to deliver the genetic code of the spike protein of COVID-19.  An application for U.S. FDA review seems imminent and its EUA approval would be a welcome added “tool” to our public health response to the pandemic.  This is because the AstraZeneca vaccine has much less of the logistical problems that have been experienced with either the Pfizer or Moderna vaccines.  Although the AstraZeneca vaccine requires 2 doses (separated by 28 days), it can be stored at standard refrigeration temperature.  Also, the AstraZeneca vaccine does not contain polyethylene glycol (PEG), which is the leading contender for the rare severe allergic reactions (called anaphylaxis) that have been observed with both the Pfizer and Moderna vaccines. A third and very important aspect of the AstraZeneca vaccine is that it can be made very cheaply (the equivalent of ~US$3-4 per dose) so that even low- and middle-income countries (LMICs) might be able to afford purchasing the vaccine for their populations.

There is also news with other COVID-19 vaccines around the world. The Russian Sputnik V vaccine (made by Gamaleya National Research Centre of Epidemiology and Microbiology, a state institute) is another virus-vectored vaccine that is purported to provide ~91% efficacy. The Chinese Coronavac vaccine (made by Sinovac, a Beijing-based biopharmaceutical company) is a more traditional-approach vaccine, based on inactivated (killed) viruses, with an alleged efficacy of between 50-91% efficacy; the wide efficacy is based on two separate press releases of interim analyses.  A second Chinese vaccine (made by Sinopharm, a state-owned company) is also an inactivated virus vaccine for which the company maintains shows 79% efficacy.  For these three COVID-19 vaccines, the data has not been released to the public and so none of these claims can be substantiated. None of these vaccines are being considered for use in the U.S. however they may be effective vaccines for the rest of the world, including LMICs, so that we can quickly end this pandemic.

On another topic, scientists have been closely tracking “variant” viruses. One notable variant virus, known as B.1.1.7, has rapidly spread throughout the U.K., a few other European countries, and was just detected in Colorado. The genetic sequence of the B.1.1.7 virus shows 17 mutations from the “original” virus, and these appear to allow this variant virus to spread more easily among humans. Thankfully, the B.1.1.7 virus has not been found to cause more severe disease.  There is another variant virus primarily circulating in South Africa, known as 501.V2 (or B1.351), which is also being closely monitored by scientists as it has many of the same mutations as the U.K. B.1.1.7 virus.  The COVID-19 vaccines that have been recently approved or that are in advanced clinical development are hypothesized to protect against these variant viruses. The laboratory studies to confirm this suspicion are underway.

The rolling out of vaccines appears to be slower than desired. It must be recognized that preparing for and implementing mass vaccinations, while maintaining physical distancing and proper processes to manage adverse events (such as rare severe allergic reactions or fainting), is a very large logistical hurdle. There are limited doses of vaccine that are being prioritized first to healthcare personnel (~21 million across the U.S.) and residents of long-term care facilities (~3 million), as these two special populations are at high-risk of infection or high-risk of severe disease with infection.  In the next few weeks and months, more vaccine supplies will become available, the next priority populations to target for vaccination will be older adults age 75 years and older (~21 million) and “frontline” essential workers (those who cannot telework as part of their occupation and have jobs that have been deemed critical for basic society to function; ~30 million). Afterwards, the next priority populations for vaccination will be older adults age 65-74 years (~32 million), adults age 18-64 years with high-risk medical conditions (~110 million), and essential workers that are not frontline (~57 million). Finally, the remainder of the population that has not yet been vaccinated will be vaccinated.

However, vaccines that are not taken up when offered will not be effective and there is a large amount of vaccine hesitancy in the population.  According to recent polling (late November) by organizations such as Gallup and the Pew Research Center, 60-63% of people responded that they would definitely or probably get the vaccine if made available today. This is an improvement from a low in September when ~50% of people responded positively to getting vaccinated.  However, that means that currently ~35-40% of the population would not get vaccinated and this could delay hopes for re-opening society.

Therefore, the final message as we welcome the New Year is that we must continue to build our faith and trust in the vaccines that are being developed. There are two vaccines being deployed and more that are anticipated to possibly be available soon.  The vaccines have proven to be safe and effective enough to demonstrate their value. The vaccines have been found to have adverse effects, but the risks can be managed and the benefit of vaccination far outweighs the potential for harm. I encourage everyone to become vaccine ambassadors and get vaccinated.

About the Author: Dr. Wilbur Chen is an adult infectious disease physician-scientist with a specific interest in clinical vaccinology. He is Professor of Medicine at the 网红爆料 School of Medicine (UMSOM), Chief of the Adult Clinical Studies section within the Center for Vaccine Development and Global Health (CVD, an organized rebsearch center of UMSOM), and Director of the 网红爆料, Baltimore (UMB) Travel Medicine Practice. Dr. Chen has served in a pivotal role in the COVID-19 pandemic as a member of Maryland Governor Larry Hogan’s COVID-19 taskforce. He is advising the state on vaccine development and distribution as well as COVID-19 safety initiatives. During the 2009 H1N1 pandemic, Dr. Chen was the principal investigator of the NIH--sponsored national H1N1 vaccine trials. Within the present COVID-19 pandemic, Dr. Chen is also co-leading the Maryland Department of Health (MDH) state-wide serological surveillance program of COVID-19, and is co-principal investigator of a CDC-funded COVID-19 syndromic surveillance program which is being implemented through the 网红爆料 Medical System.