A vaccine for the coronavirus?

We have all been living in the “new normal” of the coronavirus pandemic for some time now. As the conversation turns toward the path to restarting the economy, the question on a lot of people’s minds – including mine – is when we may have a coronavirus vaccine, which would help avoid the risk of widespread second wave of infections.

It is an important question, and one to which unfortunately, there isn’t one simple answer.

Developing a vaccine is complex even when there isn’t a global pandemic. There are many reasons for this, including the virus’ virology. To develop a vaccine, scientists need to be able to identify the virus’ mode of infection and then find an effective way to block it, thus preventing it from replicating and spreading to other cells.

In the case of some viruses – like smallpox or measles – vaccines confer lifelong immunity. This is because while the virus undergoes mutations, those mutations do not change the way the virus infects the cell. Other viruses, like the seasonal flu or tetanus, mutate enough over time for the same vaccine to no longer be effective. How long the immunity conferred by a vaccine lasts also depends on the rate of the virus’ mutation. We have to get a flu vaccine each year to protect against that year’s strain, whereas a tetanus vaccine is effective for several years.

The COVID-19 coronavirus is still very new to all of us and it will take some time to understand its virology, the rate at which it is mutating, whether those mutations affect its mode of infection and how effective any vaccine will be against it. The good news is, the virus’ genetic code has been mapped and countless scientists around the world are working on dozens of trials to develop an effective defense against the coronavirus. Just as the mountain of news and information about coronavirus treatments and a potential vaccine can be overwhelming, we are also hearing a lot of new terms in relation to the new virus, which can be confusing. 

Here are a few simple explanations for the new terms that have entered into our common vernacular during this pandemic.

Contact tracing

Contact tracing is the process of identifying people who were potentially exposed to someone who tested positive for the virus. Through robust contact tracing, we can know who to monitor or quarantine until the chain of transmission is halted.

Serology testing

The term refers to the measurement of antibodies, which are specific proteins made in response to infection, in the blood. Antibody test results are important in detecting evidence of infection. These tests can be helpful to determine how much of the population has been exposed to the coronavirus and help guide the response to the pandemic.

Herd immunity

Herd immunity occurs when a sufficient proportion of a population is immune to an infectious disease (through vaccination and/or prior illness) to make its spread from person to person less likely. It’s an important goal because even individuals not vaccinated (such as newborns and those with chronic illnesses) are offered some protection because the disease has little opportunity to spread within the community.