Thread by @prital_

@AdelineBlue1 @WHOKenya 1/ Hi, Thank you for your concern. It may seem like this vaccine is "pulled off the market", but this is NOT true. Places like Canada & Europe (currently rolling out this vaccine) have 2 stringent safety guards in place before any therapeutic is approved.

@AdelineBlue1 @WHOKenya 2/ The vaccine must: A: Undergo thorough review of clinical trial data by independent review bodies (e.g. Health Canada). People on these bodies are independent of pharmaceutical companies and have decades of medical and scientific experience to look for red flags.

@AdelineBlue1 @WHOKenya 3/ and B. Have a system in place for people like you and I to report any adverse events that happen to us after receiving the vaccine. This is called pharmacovigilance and is purposely put in place to proactively investigate any reported adverse events however rare.

@AdelineBlue1 @WHOKenya 4/ Let’s talk about the whys of pharmacovigilance: Whatever happened before e.g. pregnancies, miscarriages, strokes etc. will continue to happen at the same back ground rate. When you have mass roll out of a vaccine there are likely to be events that may occur around

@AdelineBlue1 @WHOKenya 5/ the time of vaccination but do NOT occur DIRECTLY BECAUSE of the vaccine. To distinguish this, pharmacovigilance comes in

@AdelineBlue1 @WHOKenya 6/ Having pharmacovigilance helps us answer: 1. Is an event happening more frequently than the background rate? 2. Is it linked to vaccine & what is the mechanism? 3. Who is at risk? 4. How can we mitigate this risk (therapeutics, awareness, and altering guidelines)

@AdelineBlue1 @WHOKenya 7/ So let’s talk about the events that happened that triggered the PAUSE in roll out.
In Europe, a signal was detected that there MAY be a very RARE blot clot event that occurs after vaccination. Roll out was PAUSED while they investigated this TRANSPARENTLY. Following

@AdelineBlue1 @WHOKenya 8/ investigation, they did NOT find that this vaccine increased the risk of blot clot formation above the background rate.

@AdelineBlue1 @WHOKenya 9/ However, they were UNABLE to conclusively determine whether a specific rare blood clot event (CVST) associated with low platelet counts in 25 out of a whopping 20 MILLION in UK/EU who were vaccinated with AZ was linked this vaccine. They continue to investigate

@AdelineBlue1 @WHOKenya 10/ this closely and have a mechanism by which this may be occurring (now termed VIPIT).

@AdelineBlue1 @WHOKenya 11/ So what has happened since? Given this is a rare event, and given that the morbidity and mortality of COVID-19 itself is high, the benefits of this vaccine greatly outweigh the risks.* Europe has since RESUMED roll out of this vaccine. Germany and Canada have

@AdelineBlue1 @WHOKenya 12/ placed a temporary age restriction (only those above 55-60 can get the AZ vaccine) while they investigate this further as the rare blood clot events have occurred primarily in younger people. If this vaccine is indeed linked to the rare blood clot events, and

@AdelineBlue1 @WHOKenya 13/ there are specific factors e.g. age and sex that are associated with it, the risk and benefits will be re-evaluated and guidelines will change. What else has happened since? Doctors have come together to put together therapeutic guidelines on how to treat these

@AdelineBlue1 @WHOKenya 14/ rare blood clot conditions and are now alert and actively looking out for this. See this document put out by Ontario: covid19-sciencetable.ca/sciencebrief/v…

@AdelineBlue1 @WHOKenya 15/ This is the purpose of pharmacovigilance. And it is working.

@AdelineBlue1 @WHOKenya 16/ One more thing. People in resource limited countries do not have the means to access well-resourced medical facilities that first world countries have. Without vaccines, so many many many more people will suffer or worse die from COVID-19 . Let’s look at best

@AdelineBlue1 @WHOKenya 17/ case scenario from a well resourced country like Canada. *We know that ~1 in 100 people infected with COVID-19 require intensive care, and of those 1 in 5 Canadians end up with blood clots. Mortality rates are high in those hospitalised. So when we say that

@AdelineBlue1 @WHOKenya 18/ the benefits far outweigh any potential risks THIS is what we mean. Cases are spiking in many places, without vaccination many vulnerable people will not make it, and those who do may suffer long term consequences.

@AdelineBlue1 @WHOKenya 19/ All approved vaccines nearly eliminate your chances of severe COVID-19 and death. The benefits are clear.

@AdelineBlue1 @WHOKenya 20/ On a personal note: As an under 55 year old, I have received this shot in Australia. Also both my parents received their first shot in Canada. I was born in Kenya and this country has a special place in my heart. This is personal to me. I am so happy that there

@AdelineBlue1 @WHOKenya 21/ is some relief in the form of vaccines in my birth country & that they aren’t being left behind. The current guidelines for roll out for Kenya, (those above 58) are in line with what countries with excellent pharmacovigilance systems like UK/ Europe/ Canada

@AdelineBlue1 @WHOKenya 22/ are doing. In those 55-65 years and above, the risk from a blood clot even IF linked to vaccine, are very rare. In contrast, the benefits are clear.

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