Although the COVID-19 pandemic is recent, pandemics have plagued humans throughout history, decimating communities. Pandemics of plague, smallpox, measles, chickenpox, mumps, whooping cough, influenza, typhoid fever, cholera and many other microbial pathogens have had profound impacts on humanity, and some continue to impact many people around the world.
Once an airborne infectious disease becomes a pandemic, it rarely disappears. Like seasonal influenza, the pathogen returns over and over again, infecting many people with each visit, rather than generating herd immunity. For example, devastating outbreaks of bubonic plague recurred in England every two to five years from 1361-1480.
Containment can reduce the transmission of airborne diseases and save lives by flattening the curve, but does not eliminate the risk of another round of infection once the containment measures are no longer in place. With the efficiency of international flights, it is possible to acquire an infection and travel to another corner of the globe before symptoms appear, potentially reinfecting a community that seemed to have eradicated transmission.
The most effective way to break this cycle is development of an effective vaccine. The impact of vaccines on pandemic diseases is nicely illustrated in the Vaccine Timeline printed along the lower border of this issue of Microcosm.
An effective vaccine will provide protection for the individual, but for a vaccine to prevent ongoing disease in the community, a sufficient proportion of the population must be vaccinated such that the transmission of the pathogen is effectively stopped – that is – enough people must be vaccinated to safely achieve herd immunity. And that means that the vaccine has to be widely accepted.
Wide acceptance of a vaccine requires that the vaccine has proven to be safe and effective. Demonstrating the safety and efficacy of vaccines relies on carefully controlled clinical trials. When we are in the middle of a pandemic like COVID-19, there is a tremendous desire to rush the clinical trials to get a vaccine to market as quickly as possible. But how can clinical trials be done faster and still be trustworthy? The article "Can Clinical Trials Be Improved?" provides thoughtful perspectives on this question.
Two other articles in this issue address the continuing search for effective vaccines that could save many lives and thwart pandemic threats: an HIV vaccine and a universal influenza vaccine. Despite tremendous scientific efforts and innovative approaches, these vaccines have been elusive so far. These two articles describe the challenges faced in developing these vaccines and optimism for future success.
Nevertheless, having a safe and effective vaccine is not enough. Even when the science is thorough and the data is solid, the population has to trust that the vaccine will not harm themselves or their families.
The article "Rebuilding Trust for Underrepresented Populations" discusses the challenges of regaining the confidence of vulnerable communities that had previous negative experiences with the medical system. Rebuilding this trust is crucial for reducing health disparities in marginalized populations. In contrast to the experiences of marginalized populations, vaccine deniers doubt the safety of vaccines based upon misinformation and misunderstanding. The fold-out in this issue of Microcosm provides concise, actionable recommendations for how you can effectively communicate the seriousness of COVID-19 and the crucial role of vaccines to friends, neighbors and colleagues. This one-page synopsis is meant to be "torn out" and used as a resource.
Overcoming these infectious disease challenges is crucial for human health, but microbiology is continuing to make important discoveries in many other areas as well. Some recent microbiology publications that we thought were particularly cool are highlighted in the "What's Hot" feature. A broad, robust basic research portfolio continues to be the essential pipeline for new applications. As highlighted by the recent Nobel Prize awarded to Emmanuelle Charpentier and Jennifer Doudna for CRISPR-Cas9, important scientific applications often come from areas of research that couldn't be predicted from the outset.
Stanley Maloy, Ph.D.
Editor in Chief