With all of the Kovid-19 vaccines being rolled out worldwide, none have been so controversial as the Oxford University / AstraZeneca vaccine, raising questions about its effectiveness and its side effects.
Seeing it Stop elsewhere in rollout of AstraZeneca vaccine, What is the latest on who should receive the AstraZeneca vaccine in Australia and what not? Should Australians be concerned about our dependence on it? And has the commentary to date been unbiased?
Latest on side effects
On Friday, Australia’s drug regulator, the Medical Goods Administration, said it would launch an investigation A possible link between the AstraZeneca vaccine and 44-year-old Melbourne who was hospitalized with a blood clot.
While health officials here said the case would not affect the rollout of the vaccine, and insisted that there was no confirmed causal link between the vaccine and the case, the acting Chief Medical Officer of Australia, Prof Michael Kidd, Officials said that the matter was being taken very seriously.
The head of TGA, John Skerritt, said that the Australian Technical Advisory Group (ATAGI) and the National Vaccine Safety Screening Group on Immunization were both monitoring the situation here and abroad, and ATAGI aimed to help state health workers develop new Guidelines have been issued to identify and respond to any possible instances of clotting cases.
This followed the suspension of the rollout in several other countries. on Wednesday, German health officials in Berlin and Munich suspend rollout AstraZeneca vaccine for people under 60 years old following new concerns around rare blood clots. Just a day before Canada Same move Due to similar concerns to prevent rollout for people under 55 years of age.
It follows a previous review of clotting by European and UK health authorities, as well as a review of that data by Australian regulators. The review found that the number of reported blood clotting cases after vaccination was lower than expected in the general population both in large clinical trials and during rollout worldwide.
There are a very small number of cases of rare blood clotting disease (known as diffuse intravascular coagulation) after vaccination, as well as extremely rare cases of clots in the vessels that drain blood from the brain (cerebral Venus is known as sinus thrombosis)).
It has not been proven that these cases were caused by the vaccine but, in Britain, Seven deaths related to slap have occurred among the recipient of Jab.. The UK Medicines and Healthcare Products Regulatory Agency noted that such cases are extremely rare: as of 24 March, an 18.1m dose of the Kovid-19 Oxford vaccine had been given.
The TGA notes that this condition is sometimes seen even in people who have not received the Kovid-19 vaccine. But Canada’s National Advisory Committee on Immunization said new data from Europe showed that the risk of blood clots could be one in 100,000, and it appears that women under 55 are at greatest risk. Was.
Is there an alternative to AstraZeneca?
Australia is relying too much on the AstraZeneca vaccine – by removing 53.8m doses during the year. The only other vaccine currently available in Australia is Pfizer’s mRNA vaccine, but With a fraction of the 20 m dose of this vaccine available In the initial phase of the rollout, all but the most at-risk people will receive the AstraZeneca vaccine for now. A third vaccine, known as Novavax, is also being investigated by Australian regulators and will be approved by the end of June.
Who Should Not Get the AstraZeneca Vaccine?
For some time, the Australian Technical Advisory Group on Immunization has suggested that any Kovid-19 vaccination (not just the AstraZeneca vaccine) should be protected in people who have a history of the following rare conditions:
People with confirmed medical history of CVST.
People with a confirmed medical history of heparin induced thrombocytopenia, when people developed a low platelet count after being given blood thinning heparin.
These are precautionary steps, until regulators obtain more data and do analysis. There are no remedies due to any proven link between these conditions and complications.
People with a history of severe allergic reaction to any component of the vaccine should not take it, and the same applies to the Pfizer vaccine. In Australia, the vaccine is not approved for people under 18 years of age for AstraZeneca or 16 years for Pfizer.
Professor Greg Dorey, an infectious disease physician and researcher at the Kirby Institute at the University of New South Wales, said overall, “I don’t think there’s a group that should preferably apply one vaccine to another. If you’re on it sometime this year If we want to get vaccination coverage, we need to go with the current strategy. But Novavax may also be available from June. “
What about efficacy? Will the Pfizer vaccine not give me more protection?
It is useful to remember that when the epidemic was originally declared, the world Health The organization said that controlling the virus requires vaccine efficacy of 50% or above, and anything above that would be welcome.
The latest data from AstraZeneca shows the efficacy of the vaccine at 76% with symptoms, 15 days or longer after receiving two doses four weeks apart. Clinical trials put the vaccine confidence interval between 68% and 82%. This means that if this experiment was repeated multiple times, a 95% confidence interval would yield true efficacy. Overall, efficacy does not differ substantially for other vaccines, including Pfizer.
As more data is added, the confidence interval is usually stronger and provides greater certainty. Studies have shown that efficacy has increased to 82.4%, If doses are given at least 12 weeks apart, and Australian regulators recommend a 12-week interval.
This is not really much different from the efficacy of the Pfizer vaccine, Which has an efficacy of over 89%. Both these vaccines appear to have 100% efficacy to date when it protects against severe illness and death.
Are the elderly not worried about receiving the AstraZeneca vaccine?
It is true that limited data are still available on the efficacy and safety of vaccines in persons over 65 years of age.
But the TGA states that “the vaccine has been shown to create an immune response in this group and can be used in general clinical trial populations based on demonstrated efficacy and safety”.
As with any patient, the decision to vaccinate an elderly patient depends on comorbidities and their environment (as if they are in aged care). Further clinical trials and post-market monitoring are expected to provide further information in the coming months.
The head of the TGA, Professor John Skerritt, has made it clear that there is no upper age limit for the vaccine.
“Our analysis of the data gives us no reason to suspect that the vaccine will not be fully effective in older groups,” he said.
Laureate Professor Peter Doherty, who shared the 1996 Nobel Drug Prize with Swiss colleague Rolf Zinarknegal for his discoveries about transplant and immunity, turned 80 on Wednesday and received the AstraZeneca vaccine on Wednesday.
“I’m happy to be the poster boy for the AstraZeneca vaccine,” he told Guardian Australia. “It has worked very well and has been given to a large number of people in the United Kingdom, and they have given it side by side with Pfizer and both appear to be working on each other as well. It is working very well in the UK. So I am very happy to have the AstraZeneca vaccine. “
Are there other side effects of vaccines?
Some are posting social media that is spreading misinformation and fear about the ill effects and side effects. It is important to remember that almost every health regulator in the world, as well as independent panels of consumer advocates, researchers, doctors, and scientists are reviewing safety and side-effect data at all times. It would be impossible to hide any serious adverse reactions.
For any drug, whether a vaccine or other drug, rare, the “one in a million” side-effect can only be known once when it is widely rolled out. There may never be enough people in a clinical trial to detect these events. But they are so rare that the disease, in this case, Kovid, is often very risky for health.
“When you give a drug to 50 million people, when you search for side-effects, you need to remember that certain issues are detected that occur anyway and that the person gets vaccinated Was imposed or not, ”said Doherty.
The most common side effects are mild and similar to the Pfizer and AstraZeneca vaccines: tenderness and pain at the injection site, feeling tired, chills or fever, headaches and joint pains or muscle aches. People receiving the AstraZeneca vaccine may experience nausea more frequently than those receiving the Pfizer, although it is still common with the Pfizer vaccine.
The independent expert review in Australia of suspected anaphylaxis (severe allergic reaction) cases following the AstraZeneca vaccine concluded that there is no risk of vaccine-associated anaphylaxis above the expected rate for any vaccine.
“Anaphylaxis is a very rare side-effect that can occur with any vaccine,” TGA said, and it’s important to note that people are monitored for 15 minutes after receiving the vaccine.
Source link: https://www.theguardian.com/society/2021/mar/31/why-australia-remains-confident-in-astrazeneca-vaccine-as-two-countries-put-rollout-on-ice