“I’m not having the vaccine. It kills people”, was the uncompromising response from one of my patients when I asked her if she was getting vaccinated. I can’t give much more detail of our discussion as consultations are confidential, but the background to her statement goes something like this.
She explained that a friend of hers knew of a man who developed a stroke three days after his Covid vaccination. The family were distraught and asked the doctor if the vaccine was the cause of the stroke. The doctor was not sure but reported the case to Medsafe. The family took this to mean the doctor thought there was a link. The family members talked to their friends, and soon the story was going around that the vaccine caused strokes. The situation escalated when another friend explained that all the complications from the vaccine are listed on the Medsafe website. This included a significant number of deaths. To make things worse, the friend explained that the government was keeping this information from us; this was beginning to sound like a conspiracy theory.
Is it true that large numbers are dying from the vaccine? Most definitely not.
Before I explain what is actually recorded on the Medsafe website, it is important to understand a fundamental principle used to evaluate complications from a treatment or medication.
Ice cream and sunburn
Most of us like ice cream (including my youngest), but did you know this humble dessert can cause harm. Eating ice cream is associated with sunburn. The more ice cream that is consumed, the more people get sunburn. Do we believe that eating ice cream really causes sunburn? There is a correlation between the two because both occur in the Summer; we eat ice cream when it’s hot and more people get sunburn when it’s hot. There is a correlation between ice cream consumption and sunburn but not causation; one does not cause the other. This is a fundamental concept as it is easy to jump to the conclusion that one event causes another. So how does this apply to the COVID vaccine?
Medsafe and CARM
Medsafe has to approve all new medications in New Zealand to ensure they are safe. Part of the assessment is to look at the range of side effects and complications. However, not all side effects are known for new drugs. They only become apparent over time. Therefore doctors are encouraged to report any untoward effects of the new medication to the Centre for Adverse Reactions Monitoring (CARM). CARM then tries to see if the side effect is caused by the drug.
Sometimes it’s easy to make a connection. For example, if a patient vomits two hours after every tablet and the vomiting stops when they stop taking their medication, the association is clear. However, when the patient develops a stroke three days after vaccination, it is much harder to make a clear link; the vaccine may have caused the stroke, but it could have occurred by chance; the patient was going to have a stroke anyway.
So how do we know which is true? The only way to establish a clear link is to look at many cases and have a control or comparison group.
Stroke incidence unchanged
I will use stroke as an example. Let’s assume that there are on average 100 strokes in New Zealand every month. After the vaccination programme has been going one month, the incidence of stroke is still 100, but three of these stroke patients received the Covid vaccine the week before they had their stroke. The doctors involved are concerned, and they report the cases to CARM, who documents them on their website. They do not make a causal link between the vaccine and the stroke; they just record the data. At this stage, they have no idea if the two are linked. However, the critical point is that the incidence of stroke has not changed; 100 strokes were expected, and 100 strokes occurred. No association can be made at this point. The longer the data are collected and the more cases reported, the clearer the connection becomes. If the incidence of stroke increases, this is a signal that the vaccine may cause strokes; if the incidence remains the same, a link is unlikely.
Obviously, the interpretation of results it’s not that simple. The incidence of stroke varies each month, not all patients are reported, and some have other risk factors that make a stroke more likely. So the only way to get a clear picture is to look at a vast number of cases over time.
Misinterpretation of results
So what did my patient and her friends do wrong? They misinterpreted the results. They saw strokes and deaths listed on the website and jumped to the conclusion that these complications were caused by the vaccine. Just the same as assuming eating ice cream causes sunburn. Strokes are occurring at the same rate, and thousands of people are getting vaccinated. Inevitably, some people who were destined to have a stroke will have recently received the vaccine. It doesn’t mean one caused the other.
It’s essential to realise that the information on the Medsafe site just records cases that have been referred to them, where doctors or patients themselves have raised some concern. However, it’s only with careful investigation of more significant numbers over time that it is possible to identify clear links between vaccination and a side-effect. The people at CARM are trained to do this. They look for any signals that might suggest a causal link. They investigate these very carefully and only suggest causality if they are confident their data supports this conclusion. To date, they have found no connection between the Pfizer vaccine and stroke, and only one death is thought to be linked to the vaccine, and that is still under investigation.
The bottom line is that the vaccine is safe.