News Article: “Coronavirus: Spanish Study casts doubt on herd immunity feasibility“
BBC News Original article: www.bbc.com/news/world-europe-53315983
Written by Annabelle Ngai & Anthony Siu 27 July 2020
WHAT IS HERD IMMUNITY?
Before getting into the conclusions drawn by the Spanish Study, let us first understand the concept of herd immunity.
Generally speaking, herd immunity is achieved when a huge proportion of a population becomes immune to a disease.
There are two main ways to achieve herd immunity.
Widespread vaccination. Polio and rubella are a few of the many contagious diseases which have been successfully contained due to widespread vaccination. However, immunity gained from vaccines may wane with time as new strains form, requiring revaccination.
Natural infection. When a population is exposed to a disease and recovers from the infection, they will develop antibodies against future infection (ie, immunity). If a sufficient proportion of the population develops immunity (known as the threshold point), herd immunity is reached.
The threshold for achieving herd immunity varies from disease to disease. Using the contagious disease measles as an example, the threshold is about 95%. For COVID-19, experts currently estimate the threshold to be about 70%.
Although this might seem easier to achieve than the 95% rate for measles, a current Spanish study suggests that there is still a long way to go.
ACCORDING TO THE SPANISH STUDY
The development of herd immunity for COVID-19 is not as straightforward as many may have thought.
The study found that of a sample size of 60,000 people, only around 5% had developed antibodies. The study further shares that long lasting immunity may not necessarily build up in individuals under such a lethal infection like COVID-19 which has a death rate of over 10% in some countries. Rather, the immunity that is built up may merely be short-lived with possible repeated infections. The concept of developing herd immunity is still valid, but reaching it without a vaccine will be a costly move.
This study therefore reinforces the idea that social distancing measures should be continually enacted to minimise the risk of catching the disease for the general public and reduce the burden placed on healthcare systems worldwide.
HOW IT HELPS WITH MEDICAL SCHOOL APPLICATION
Herd immunity and vaccinations are common medical topics that can be brought up during interviews, more so given this current pandemic, so having some sort of background knowledge about them will definitely get you more prepared!
To be certain on whether you understand a certain topic/concept, not only should you familiarize yourself with the definition but also make sure you know how to explain the concept to others. That's good practise for your medical school interview as well.
For example, a common interview question would be the following: what do you think is the greatest breakthrough in medicine?
★ When I was practising this question last year, the answer I gave was vaccines. The benefit of inducing herd immunity is a big reason why I chose it as the greatest breakthrough amongst others such as gene editing and antibiotics!
Another question to consider would be regarding medical ethics.
There were numerous protests regarding social distancing citing it as a restriction of people’s freedoms. From an ethical standpoint, do you agree with these protests?
★ It is important to consider both sides here, just like any ethical scenario. Do consider applying the 4 pillars of medical ethics here as this involves consideration on almost all 4 of them (non-maleficence, beneficence, autonomy, and justice).
★ A key factor to keep in mind while answering this question is the importance of securing not just an individual's right and health, but also public health.