When should you get your second dose of AstraZenica? (NOTE: This is not medical advice.)

The question as to when you should get your second dose of AstraZenica is often discussed with family and friends. I couldn't help feeling the shorter time of 6 weeks reduced from 12 weeks may have been more to meet government targets than the health needs of people. Having said that, in areas where there was substantial risk the shorter period could well have been warranted. The level of risk across Australia is not the same but unfortunately the messages we may be receiving from the mainstream news media does not differentiate the level of risk.

Ultimately each of us has to take responsibility for our own health choices. With so much information, misinformation, and sometime questionable information, it can be very hard to make better choices. Sometimes pressure from those around us will lead us to make  choices that may not be in our best health interests.

I keep a close watch on the level of risk around me so if possible my choice is to see if I can wait 12 weeks for the second dose of AstraZenica. Why? Because in theory this should give me a greater level of protection based on the efficacy research. I don't consider this to be a perfect choice, just a potentially better choice.

A second and potentially more important point comes from the reference linked to from the document linked below which states:

"Yet we do know two doses of the AstraZeneca vaccine protects against serious COVID-19 after infection with the Delta variant, whereas one dose doesn’t."

The link provided then leads to the research article which states:

"Sera from individuals who had received one dose of the Pfizer or the AstraZeneca vaccine had a barely discernible inhibitory effect on the Delta variant. Administration of two doses of the vaccine generated a neutralizing response in 95% of individuals, with titres three- to fivefold lower against the Delta variant than against the Alpha variant. "

This to me is more of a concern. Children are now back at school and in childcare centres. Borders are starting to open up. The risk of catching COVID-19 would appear to be rapidly increasing. Increased efficacy is good, but not if a single dose doesn't protect you against serious COVID-19 infection. That is the quandary we're all faced with.

Please keep in mind I have no medical background. Do not take the information provided as advice or guidance. This is just my own personal choice.

To help guide my choice I've read a considerable amount of information on the internet so I decided to find an article I felt could summarise the efficacy information. The following is from doctors in Erina NSW who summarise the information well and provide supporting links. I've not yet found the actual information in the Lancet, but it does correspond with other information I've found.

WHEN SHOULD I HAVE MY 2ND ASTRAZENECA VACCINE? – Your Family Doctors

The linked article is quite good to read as it concludes that even if getting the AstraZenica second dose early may be sub-optimal, if this is followed up by a later Pfizer dose this will further boost immunity.

One missing piece of information I've not yet found is that whilst we know the booster is needed for Pfizer as protection diminishes over time, I've not seen evidence this is the case for AstraZenica. I feel the government will recommend a Pfizer booster as it is a simpler message, but is it needed if you've waited the full 12 weeks for a second dose of AstraZenica. Only time and further research will tell.

I hope the information provided helps in some way.

Kelvin