As a young schoolboy I remember one day that classes suddenly stopped. We filed out to the long corridor and joined the queue. People were there who I had never seen before at our school: people in white coats with documents and tables and long lines of … white spoons!

When my turn came, I was told to take the spoon and swallow. The drop of liquid was pink and sugary; it went down the hatch easily. But I was nervous – who wouldn’t be when a total stranger tells you to swallow a foreign substance?

The pink liquid was of course the vaccine against polio, a dreadful and feared disease. As a virologist working at the former Fairfield Hospital for Infectious Diseases in Melbourne, I saw first-hand the devastating effects of polio paralysis. One man I met had lived at the hospital for decades. He was unable to breath for himself and needed the 24/7 support of an artificial lung.  Today we thank God for the Salk vaccine and the virtual eradication of polio.

Now it’s 2021 and we face a new and very different disease. For a year, concern about Covid-19 has dominated our ‘collective consciousness’. As news of a possible vaccine began to break, there was a communal sigh of relief – or at least of hope – that this pandemic could end soon. And, thankfully, vaccines have been developed (with a big shout-out to those teams of scientists who developed and tested Covid-19 vaccines in record time). But there is also a collective concern, even fear, of the new vaccines.
As vaccines become available, it is only natural to ask questions: How do they work? Are they safe? After all, we humans are averse to allowing strange and foreign substances into our bodies!

The goal of a vaccine is to cause an immune response to a specific bug like a virus without the harmful effects that the virus itself causes.

Let me tell you about these vaccines, particularly the messenger RNA (mRNA) vaccines produced by Pfizer/BioNTech and Moderna. They are the first to complete phase-3 testing and the first-ever mRNA vaccines approved for human use.

Messenger RNA vaccines – A new way to make a vaccine

The goal of a vaccine is to cause an immune response to a specific bug like a virus without the harmful effects that the virus itself causes. It’s that immune response from our bodies that gives us protection from the virus and the disease it causes. Many vaccines used in the past against non-Covid diseases have consisted of the actual virus that has been killed or somehow rendered inactive. But the Covid-19 mRNA vaccine is different. Instead of injecting whole virus particles, the mRNA vaccine is a small and incomplete part of the genetic material of the virus (its mRNA).

The mRNA is wrapped in a harmless coating to offer some protection to the mRNA after injection. Once inside our cells, the mRNA becomes the ‘messenger’ (that’s the “m” in mRNA) that instructs our bodies to make copies of a particular part (the spike protein) of Covid-19. Then, this protein causes an immune response that is specific enough to protect against the actual virus if we are exposed to Covid-19 in the future.

No need to worry – thank God!

Besides the already comprehensive testing phases these vaccines have undergone, there are at least four good reasons we can be confident that an mRNA Covid vaccine is safe:

• This vaccine is neither a weakened nor a killed whole virus, so the risks associated with those traditional vaccine designs (that is, the possibility of actual harmful infection from the vaccine) are avoided.
•  The mRNA Covid vaccine is designed to trigger the cells in our body to make just a piece of virus protein; this piece cannot cause Covid-19 because it lacks all the rest of the machinery of the whole virus. But it can and does produce a safe immune response.
• It may sound worrying that mRNA vaccines consist of genetic material: Can this material somehow interfere with our own DNA? However, there is no need to worry. The mRNA simply does not enter the part of each cell (the nucleus) where our DNA resides so there is no interaction with our own DNA.
•  To further add to the vaccine’s safety, the mRNA from the vaccine is quickly degraded by our cells after it has finished making the protein it was designed to make. This is partly because mRNA is naturally far less stable than DNA. It won’t last long in the cell before it is effectively destroyed.

So, as a Christian, I give thanks to God that we have developed Covid-19 vaccines far more rapidly than vaccines of previous decades. Thank God for the science that will save millions of lives. Thank God that mRNA vaccines can be produced in larger amounts, more simply, and with greater precision than older whole-virus vaccines. Thank God for his provision of medical science and the good that comes of it.

David Hooker is trained in science and theology and currently on the teaching staff in biomedical science at Monash University. Formally a pastor, he has recently completed his doctoral studies with the Australian College of Theology, synthesising science and theology on the topic of human ageing.

David is a member of ISCAST–Christians in Science and Technology. ISCAST is a network of people in Australia, from students to academics, exploring the interface of science, technology, and Christianity.