By Da Young Kang
For the last several months, countries around the world have instituted social distancing and mask requirements in response to the coronavirus pandemic. With over five hundred thousand deaths each day worldwide due to COVID-19, many are convinced the only way to return to normal and prevent more deaths is the development of a vaccine.
The first vaccine ever was developed by an English doctor named Edward Jenner. In 1796, he performed an experiment on an 8-year-old boy, injecting pus from a cowpox pustule into the patient’s arm. Jenner’s experiment proved successful and protected the boy from smallpox, a widespread and deadly disease at the time. Although his methods are controversial — inserting a part of an animal into a human — Jenner’s vaccine was accepted for its favorable effects. He also coined the word “vaccine,” from the Latin word for cow, vacca. Today, he is widely known as the father of immunology.
Before discussing how vaccines themselves work, it is important to first understand how the human body responds to infections. When bacteria or viruses enter the body, they cause immune responses such as coughing, inflammation, and fever. This is called the first line of defense. The second line of defense involves macrophages which take in and digest the foreign invaders, leaving behind pieces called antigens. Next, B lymphocytes create antibodies to attack these antigens. T lymphocytes also serve to fight against infected cells. The immune system is also able to “remember” antigens, resulting in quicker and potentially more effective responses when the body encounters the same pathogen in the future.
Vaccines use this second line of defense to develop immunity against germs. This is done by injecting an imposter of pathogens or viruses to imitate an infection. As a result, the body produces antibodies and T lymphocytes without the body actually getting infected.
And now, for the million-dollar question: how long will the development of vaccines against the coronavirus take? Experts hold conflicting opinions. According to Dr. Anthony S. Fauci, the top infectious disease expert on the Trump administration’s coronavirus task force, America could have a viable vaccine ready in 12 to 18 months. However, many critics such as Robert van Exan, a cell biologist who has worked in vaccine production for decades, predict that a vaccine will not be available until 2021 or 2022 — gauging even this prediction to be highly optimistic. This more conservative view stems partially from the numerous steps that must be taken for a vaccine to be brought to the market including academic research, a pre-clinical phase (preparation for clinical trials), three phases of clinical trials, construction of factories, manufacturing, approval by the FDA, and distribution. These steps take a long time especially because less than 10% of drugs in clinical trials get approved by the FDA.
In order to accelerate the process, scientists can combine clinical trial phases and get a head start on making plans for later steps of the process. For example, factories can be built in preparation for FDA approval. Another option is to wait for the mRNA vaccine to become viable. Although the mRNA vaccine has never been made or used, this method promises faster production than other vaccines. Despite the concerning circumstances, the good news is that there are more than 254 therapies and 95 vaccines being developed for COVID-19. The World Health Organization has also announced that 75 countries have shown interest in financing the creation of vaccines and in securing equal rights to access them. For the time being, however, it is crucial to continue practicing social distancing and wearing masks.