Medical authorities believe that two doses of the Covid-19 vaccine are more effective than one. This is despite concerns that some people might be cancelling their second AstraZeneca dosage in order to get a Pfizer shot.
State premiers and health officials are urging people to get vaccinated with the latest vaccine as soon as possible and to attend their first- and second-dose appointments as outbreaks of the Delta variant occur in New South Wales and Victoria.
On Tuesday, Daniel Andrews, Victorian premier, stated that the best vaccine is the one available today. There are literally thousands upon thousands of AstraZeneca appointments that you can make online.
Brad Hazzard (NSW health minister) said that more Pfizer doses were needed to meet the demand. He said that the mixed messages about vaccines over the past six to eight months, especially AstraZeneca have not helped the wider community understand how important it was to get vaccinated with any vaccine you are eligible for.
The Australian Technical Advisory Group on Immunisation's (Atagi), advises that the Pfizer vaccine should be the preferred Covid-19 vaccine for those under 60. This is due to the possibility of a rare clotting disorder called TTS, which can be linked with AstraZeneca vaccines in this age group.
People under 60 years old have signed up for AstraZeneca vaccinations in accordance to the Atagi advice that, in cases of outbreaks where Pfizer supplies are limited, those over 60 should reconsider the benefits of being vaccinated.
Scott Morrison, the prime minister, announced Tuesday that half a billion Pfizer doses would arrive from Singapore this week. Singapore has an average of 80% Covid-19 vaccination rates. Lt Gen John Frewen, the vaccine rollout coordinator, stated earlier in August that Australia was working to bring 32m Pfizer doses forward so that 1m would arrive each week.
Some people in Victoria and New South Wales who are awaiting second-dose AstraZeneca appointments have been encouraged by the announcements to believe that they may be able to get Pfizer instead. Except in exceptional cases, Australia's vaccination hubs and general practitioners do not allow this.
Dr Omar Khorshid, the head of the Australian Medical Association (AMA), stated that there are certain people who have been vaccinated with AstraZeneca and would be interested in receiving Pfizer as a second dose. However, this doesn't make sense.
He said that the majority of TTS risk is due to the first dose. AstraZeneca vaccination may provide longer-term protection than Pfizer.
It's a simple decision for those who have received their first dose of AstraZeneca. It is a wonderful vaccine that has excellent safety and efficacy. Studies on mixing vaccines are less extensive.
Dr Karen Price, head of the Royal Australasian College of General Practitioners, stated that GPs are having a lot of conversations with patients about mixed-dosing.
She stated that mixed dosing is not allowed in Australia. We are following Atagi guidelines. Given recent AstraZeneca studies that showed positive results and the fact that the second dose has very little TTS, I don't know what people are worried about.
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Pfizer is also preferred by some people because it can be vaccinated earlier. It is best to allow at least 21 days between doses. This is in comparison to a gap between AstraZeneca doses of four to 12 weeks, with 12 weeks being the recommended time for maximum efficacy.
Price stated that if people are worried about the gap, they can speak with their doctor to discuss bringing their second AstraZeneca dosage forward to earlier 12 weeks. This is especially important in areas where there has been an outbreak.
Canada was one of the first countries to allow mixed vaccination dosing. The National Advisory Committee on Immunization issued guidance in June allowing the use of the AstraZeneca and Pfizer vaccines interchangeably.
The promising results of studies on the administration of AstraZeneca and Pfizer as a first dose are also encouraging. A preliminary preprint study by the University of Oxford, which involved 830 participants, found that the combination provoked an immune response stronger than any other vaccine combinations.
Professor Allen Cheng, Atagi co-chair and an epidemiologist and infectious disease physician in Melbourne, stated that compared to the previous clinical trials, many millions have been exposed to two doses.
He said that we have given some advice early on about the use of vaccines in clinical situations when this is needed. People who have experienced serious reactions to one or both vaccines, or who have been given a vaccine from an overseas country that isn't available here. We note that although supplies of one vaccine remain limited, it is likely that consumers will not have the option to choose from a variety of schedules.
According to him, the evidence suggests that different vaccines can produce a strong immune response, be effective and are safe. It was necessary to determine the optimal timeframe for mixing vaccines and what vaccines would be valid in other countries. A few countries have yet to recognize vaccination passports of mixed-dose patients.
It is still being worked out what constitutes a valid vaccine. This complex area involves Atagi, TGA [Therapeutic Goods Administration] as well as government. Cheng stated that proof of vaccination status is not required at this time for most workforces and does not require vaccine passports.
