It is a fact that quite a few Covid-19 vaccines have been rolled out across the globe; however, perhaps the most beleaguered one is the Oxford University/AstraZeneca vaccine, and questions are being asked regarding its efficiency and side effects.
Given that the rollout of this particular vaccine has been paused elsewhere, what is the latest information on who should be receiving the vaccine in Australia and who should not? Is there any reason for the Australians to worry?
The most recent information on side effects
It is not long ago that the rollout of this AstraZeneca vaccine has been suspended in Munich and Berlin by the German health authorities for individuals below 60 years of age following fresh concerns regarding a rare blood clotting. An identical move was also made by Canada because of the same reasons which halted the rollout of the vaccine for folks below 55 years of age.
Following the vaccination, very few people have been affected by a rare kind of blood clotting ailment (called disseminated intravascular coagulation) along with very few cases of blood clots in the vessels which drain blood from the brain (called cerebral venous sinus thrombosis). However, there is no evidence that the vaccine is responsible for causing these conditions.
According to the Therapeutic Goods Administration, the regulator of the medicines in Australia, individuals who haven’t received a Covid-19 vaccine might also suffer from these conditions. However, the National Advisory Committee on Immunization of Canada asserted that it has been suggested by new information from Europe that the risk of blood clots might be approximately 1 in 100,000. Moreover, it seemed that the females who are below 55 years of age were most likely to be affected.
Is there any substitute for AstraZeneca?
It is a fact that Australia depends on this vaccine to a great extent and 53.8m doses are being rolled out throughout the year. Pfizer’s mRNA vaccine happens to be the only other vaccine which is available presently in Australia. However, the majority of the high-risk individuals are going to receive the AstraZeneca vaccine for the time being. Another vaccine called Novavax is going to be rolled out by the Australian regulators (if sanctioned) by the conclusion of June.
Who shouldn’t receive the AstraZeneca vaccine?
Right now, it has been suggested by the Australian Technical Advisory Group on Immunization that all Covid-19 vaccinations (including the AstraZeneca vaccine) ought to be postponed for those individuals suffering from the following conditions:
• Individuals having a verified medical history of thrombocytopenia induced by heparin, in which case a low platelet count is developed by people after the blood thinner heparin is given to them.
• Individuals having a verified medical history of CVST.
Moreover, individuals who are prone to allergic reactions to any component of the AstraZeneca vaccine must not take it, and this is applicable for the Pfizer vaccine too. In fact, neither vaccine can be taken by people below 18 years of age in Australia.
What about efficiency? Will Pfizer’s vaccine provide me with more protection?
Here, we like to mention that according to the World Health Organization a vaccine efficiency of either equal to or more than 50% was imperative for controlling the virus.
According to the latest reports, the efficiency of the AstraZeneca vaccine is approximately 76% that takes place after 15 days or more of receiving 2 doses administered at the interval of 4 weeks. The confidence interval of the vaccine has been put by clinical trials at between 69% and 82%. This implies that the possibility that the true efficiency of the vaccine is between 69% and 82% is around 95% which makes it identical to other vaccines out there.
The confidence interval typically becomes more rigid providing more certainty with the addition of more data. It has been revealed by studies that efficacy can increase to as much as 82.4% in case the doses are administered at an interval of a minimum of 12 weeks, and a 12-week interval has been suggested by the Australian regulators.
This is almost similar to the Pfizer vaccine efficiency which is more than 89%. It appears that both these vaccines have an efficiency of 100% in terms of safeguarding against severe ailments and demise.
Will there be any concern in case elderly individuals get the AstraZeneca vaccine?
It is a fact that not much data is available regarding the safety and efficiency of this vaccine in individuals who are more than 65 years old.
For any particular elderly patient, the decision of immunizing will be depending on their environment, as well as comorbidities. We are expecting to have more information in the upcoming months on this particular topic.
It has been asserted by Professor John Skerritt, Head of the TGA, that the vaccine does not come with any upper age limit. Professor Peter Doherty, who has received the Nobel medicine prize for the year 1996 along with Rolf Zinkernagel for their findings regarding immunity and transplantation, happens to be 80 years of age and the AstraZeneca vaccine was administered to him only recently.
Do the vaccines come with other side effects?
You will come across several social media posts spreading misinformation as well as apprehension regarding the adverse side effects of the vaccines. You should bear in mind that virtually every regulator on the planet, as well as autonomous panels of researchers, consumer advocates, scientists, and medical practitioners, are reviewing the side effect and safety information all the time. One will find it extremely difficult to conceal any severe adverse reaction.
The side effects are quite mild when it comes to the AstraZeneca and Pfizer vaccines which include pain and tenderness at the site of the injection, feeling exhausted, headache, fever, muscle pain, or joint pain. Although individuals getting the AstraZeneca vaccine might be experiencing nausea more frequently, it is nevertheless not uncommon with the Pfizer vaccine as well.
It has been concluded by autonomous expert review in Australia that no increased threat of anaphylaxis is associated with the AstraZeneca vaccine above the projected rate for other vaccines. According to the TGA, Anaphylaxis can happen with any vaccine, and it is essential to monitor individuals for a period of 15 minutes following receiving the vaccine.