Scientists around the world are working towards effectively managing the COVID-19 pandemic. Developments are being made daily as we learn more about this virus. Here are five key developments to watch, as of January 2021.
The development and deployment of several safe and effective vaccines within one year is a remarkable scientific achievement that will dramatically help reduce the extent of disease and death. But, as has been said often, “vaccines don’t save lives, only vaccinations do.” This highlights that the development of the vaccines is only part of the equation. The next critical phase is the roll-out and deployment of the vaccine rapidly and equitably. In the United States, President Joe Biden has publicly announced an ambitious but achievable goal of administering 100 million doses in his first 100 days in office, with an estimate that enough doses will be available for 300 million people by the end of the summer.
It remains critical to continue efforts to slow the spread of the virus while the vaccine is rolled out to protect those who have not yet been vaccinated. Additionally, the more uncontrolled spread there is, the more opportunities the virus has to mutate, including the potential for what are known as “escape mutations” that may reduce the efficacy of current vaccines and treatments. Several new variants of concern have already arisen that are more highly transmissible, so it is imperative to reduce the spread of the virus while vaccination campaigns are underway. Most importantly, countries must ensure the rapid deployment of vaccines globally. This is a moral responsibility as well as a strategy to protect everyone—a threat from this virus in any one area of the globe can quickly be a threat everywhere, as we have seen throughout this pandemic.
While vaccine research often receives more media attention, therapeutics are vital to the COVID-19 response, as they have the potential to lower severe disease, hospitalization, and death. The National Institutes of Health (NIH) Treatment Guidelines have summarized the NIH’s therapeutic recommendations based on disease severity.
Steroid and antiviral therapies have also been shown to reduce risk of death in patients with severe cases of COVID-19. The steroid dexamethasone has been granted an Emergency Use Authorization, and the antiviral remdesivir developed by Gilead Sciences is the only therapeutic to have received approval by the Food and Drug Administration (FDA) to date. The therapeutics mentioned only represent the latest research, not medical endorsements. Always consult with a doctor about COVID-19 treatment.
Several monoclonal antibody-based therapies, which recognize a specific protein on the surface of the virus, have been shown to prevent disease progression in patients newly infected with COVID-19. Emergency Use Authorizations have been granted for bamlanivimab, an antibody-based therapy developed by Eli Lilly and for a casirivimab-plus-imdevimab antibody cocktail developed by Regeneron. However, it is important to note that there are concerns that a new variant of the virus may be more resistant to monoclonal antibodies.
COVID-19 diagnostic tests can be an important tool in slowing the spread of disease and have been used successfully by many organizations as part of their overall risk reduction strategy. The most common diagnostic test is PCR testing which looks for the genetic material of the virus in a person’s nose mucus, throat mucus, or, occasionally, saliva. Nose and throat PCR tests involve a long swab to collect mucus, while the saliva PCR test involves spitting into a tube. Saliva analysis also enables pooled sample testing, another strategy in which genetic material from several sources is combined before being tested for COVID-19 in order to reduce resource usage, cost, and time. A positive COVID-19 result in the pooled samples leads to retesting of all individual samples in the affected group.
The advantage of PCR testing is that this method is very sensitive and can detect the virus early on in infection. PCR-based testing also has some important limitations. These tests are administered by a trained professional or self-administered, but they require a laboratory for analysis. This means they can be expensive, and it can also take several days to receive the test result, creating long windows of time where an infectious person may not know they are infectious and therefore may not isolate before infecting others. Another issue with PCR testing is that, due to the sensitivity of the test, a person can test positive for the virus days or even weeks after they are no longer infectious.
A second type of test is a self-administered test that gives a quick result, within 15-20 minutes, without a laboratory, and is much cheaper than the PCR test (it can cost less than $5). These tests are based on lateral flow technology and sometimes referred to as “rapid tests” or antigen tests. These tests work by looking for proteins of the virus, instead of the virus’ genetic material itself, in samples from a person’s nose. As such, they are intended to detect if someone is in the acute infectious phase, a time when they are most likely to infect others. These antigen tests will not report someone as positive in the days or weeks after they are not infectious, an important advantage over PCR testing. The most important aspect of these tests is that because they are rapid, inexpensive, and self-administered, they can be taken frequently. This is critical because frequency of testing has been identified as the key aspect in determining the value of testing as a public health tool.
The use of testing has expanded across various organizations and sectors. For example, proof of a negative test is now a requirement for international air travel in many cases, and testing has been used successfully by some universities, including Harvard, to reduce risk to students living on campus. Theaters should be prepared to consider incorporating diagnostic testing, potentially including on-site rapid testing, into their planning for future gatherings or events.
“Airborne transmission” refers to the transmission of SARS-CoV-2 from an infectious person to another person via small virus-laden aerosols that are produced when the infectious person breathes, speaks, or coughs. These small aerosols can remain airborne for minutes to hours and can travel more than six feet to disperse throughout a room. These infectious aerosols can be inhaled by other people in the room unless they are removed from the air by ventilation, cleaned out of the air by filtration, or deposited on surfaces in the room by settling.
In July 2020, 239 scientists sent an open letter to the World Health Organization (WHO) calling for the organization to revise its recommendations to include this transmission method. The letter cited a large body of evidence that SARS-CoV-2 is present and infectious in small airborne droplets. In response, the WHO updated its guidelines to include the possibility of airborne transmission indoors, in crowds, or in poorly ventilated spaces, and the US Centers for Disease Control and Prevention (CDC) also acknowledged that airborne transmission can occur.
Variants of Concern
All viruses mutate. Given enough opportunity due to widespread uncontrolled transmission, genetic mutations may arise that change the nature of the virus in ways that are harmful. This can include variants that are more transmissible, cause more severe disease, or both. Some mutations can be harmless. When a new mutation arises that has the potential to cause more harm, it is referred to as a “variant of concern.” These variants are also sometimes referred to as “strains.” As of February 2021, several new variants of concern have been identified through genomic sequencing. These include variants first identified in the UK (B.1.1.7), South Africa (B.1.351), and Brazil (P.1). As of the date of this release, these new variants of concern have been shown to be more highly transmissible. In countries where they are detected, they have quickly displaced existing variants/strains that were previously circulating widely. Additionally, there is evidence that the B.1.351 and P.1 variants may not be as susceptible to some antibodies. Testing of the available vaccines against these variants of concern show that the vaccines are still highly effective, although less so against these variants than others.
The increased transmissibility of these newer variants and the potential for changes in immune response reinforce the need for rapid global vaccinations and for continued strict adherence to the control measures described in this roadmap, including mask wearing and healthy building controls, such as ventilation and filtration of indoor air.