Reports of about 30 deaths among elderly people living in nursing homes who received the Pfizer vaccine have made international headlines.
With the Australian Therapeutic Products Administration (TGA) expecting to approve the vaccine imminently and the rollout scheduled to begin next month, this development may seem a cause for concern over the safety of the vaccine.
But there are a few reasons why it shouldn’t be.
What we know
We have not seen this problem reported in any other country that is launching the Pfizer vaccine.
Norway reported that about 45,000 people across the country have been vaccinated against COVID-19 so far. Its vaccine program has focused mainly on nursing home residents.
In other countries, there may be more focus on frontline health professionals in the first place. Therefore, if there is any association between deaths in the elderly and this vaccine, it may not be apparent yet.
It also depends on surveillance. Norway can have an especially rapid surveillance and reporting system, efficiently tracking everyone who has been vaccinated and reporting any adverse results quickly.
We would expect surveillance reports from other countries with an active vaccination program soon, adding to the essential data to build a more accurate picture of vaccine safety in different populations.
Norway’s reports will sensitize other countries to closely monitor vaccine recipients, particularly those in nursing homes that are older and more vulnerable. We can see more reports on this coming in the coming weeks, from other countries.
But we can’t either. We have limited information about these cases in Norway. The people who died were elderly and very fragile. Many had significant underlying health conditions common in very old people and may be nearing the end of their lives, regardless of the vaccine.
Although they are under investigation, it is important to note that deaths have not been conclusively linked to vaccine complications. Meanwhile, Australian experts are calling for calm.
Vaccines and the elderly
In the recent history of vaccines, we have not seen trends showing deaths in the elderly after vaccination. For example, there is no evidence that the annual flu vaccine has been linked to deaths in older people – or people of any age.
It is important to note, however, that when making a comparison with the flu vaccine or other vaccine and the Pfizer vaccine for COVID-19, we are comparing apples and oranges.
The Pfizer vaccine is based on mRNA technology, which is completely new in a human vaccine. This technology introduces part of the genetic material of the SARS-CoV-2 virus in the form of messenger RNA (mRNA). This instructs your cells to be part of the virus that stimulates an immune response that inhibits infection and protects against disease.
All vaccines are designed to generate an immune response – albeit in different ways – to prepare our bodies to fight the virus if and when we find it.
The creation of an immune response leads to inflammation of the body. Some people will not experience side effects from a vaccine, but inflammation can manifest itself differently in different people and between different vaccines. This can mean a reaction at the injection site, fatigue or malaise.
The deaths in Norway were reportedly associated with fever, nausea and diarrhea, which, although they are the extreme end of the spectrum of the vaccine’s side effects, would be tolerable for the vast majority of people.
How different people will respond to mRNA is what we are beginning to understand now. It is possible that this vaccine will have more serious effects in older and vulnerable people, where the initial inflammatory response can be overwhelming.
But it is still too early to draw conclusions.
Side effects show that a vaccine is generating an immune response
Vaccines need to generate an immune response to work, and side effects are a by-product of our body that creates an immune response.
Although the deaths are sad, they should not be a cause for alarm. In fact, this tells us that the vaccine is stimulating an immune response. For most people, this response will be completely tolerable and will lead to the development of an immune memory that protects them from severe COVID-19.
The big challenge for any vaccine is to generate an immune response sufficient for you to be protected from the disease in question, but not so much that you experience serious adverse effects. Where that line in the sand exists varies from person to person, but the oldest and most fragile vaccine recipients are at the greatest risk of serious and potentially fatal reactions.
So, for those who may be more susceptible, we can be a little more cautious. In approving the Pfizer vaccine, TGA may consider advising against this particular vaccine for very elderly and fragile people, particularly those who have other conditions and are potentially near the end of their lives.
Ideally, the vaccine should be considered on a case-by-case basis for this group, carefully weighing the risks and benefits in each situation, based on the best available data. 
Nathan Bartlett, Associate Professor, School of Biomedical Sciences and Pharmacy, University of Newcastle.
This article was republished from The Conversation under a Creative Commons license. Read the original article.