A male COVID-19 expert standing outside in a suit with his arms crossed
Dr Rob Grenfell answered your questions live on Facebook.

Wouldn’t it be handy if you could carry around a COVID-19 expert in your pocket? Like Siri or Alexa – but one that could answer your technical questions, in real-time, with scientific accuracy?

Well, our recent live stream with our Director of Health and Biosecurity, Dr Rob Grenfell, allowed our community to do just that. We asked what you wanted to know about COVID-19 and, over the 30-minute session, Rob answered. If you missed the live stream here is our COVID-19 expert FAQ to get you up to speed.

I already had COVID-19, am I immune or do I still need a vaccine?

If you have had COVID-19 it’s likely you have some immunity against reinfection. But immunity that we get from vaccinating is stronger than immunity from the infection itself. For this reason it’s recommended all adults receive a vaccination, even if they’ve already had COVID-19. 

How do viruses mutate?  

SARS-CoV-2 is an RNA (ribonucleic acid) virus. The flu is also an RNA virus. It is normal and we expect these types of viruses to mutate over time. Mutation happens when the virus replicates or makes copies of itself. Its genes undergo random ‘copying errors’, which we refer to as genetic mutations. 

The mutations we’re particularly interested in are changes to the protein of the coronavirus spike protein. This is what most COVID-19 vaccines target to protect us from disease. Viruses with these mutations are called variants. Variants could differ by a single or many mutations. 

Does the Oxford-AstraZeneca vaccine work against the variant from South Africa?

At this stage, there is no peer-reviewed research on the effectiveness of the Oxford-AstraZeneca vaccine on the South African variant, also known as 501.V2 or B.1.351. We are aware there is ongoing research in South Africa on the utility of the Oxford-AstraZeneca vaccine as it stands, and we await the results of this study. The University of Oxford is also looking into modifying the vaccine so it has a stronger effect against this strain. 

It is better to have some immunity than none as various strains will continue circulating in the community. However, if needed, vaccines will be tweaked to increase their efficacy against variants of concern.  

How do I know what is in the vaccines?

The full list of ingredients for the Pfizer and Oxford-AstraZeneca vaccines are available from the Therapeutic Goods Administration.

Could a test confirm if I had COVID-19 in the past? 

Antibody or serology tests can determine if you’ve had a past infection with SARS-CoV-2, the virus that causes COVID-19. If you’re interested, you can find more information on the types of tests available through the NSW Health website.  

Who needs a couch guru or a questionable online forum when you have a qualified COVID-19 expert at your disposal? It’s not too late to catch up, tune in to the recording of the live stream below or on our Facebook page. Or, read more of our expert commentary on COVID-19.

Have another area of science you would like to ask our researchers about? Let us know in the comments and follow our social channels for future live streams just like this one.


  1. Hi John, thanks for your comment. We suggest speaking to your GP or healthcare practitioner who can understand your personal health circumstances and provide advice based on this.

    Team CSIRO

  2. I would like Dr Grenfell’s opinion on having novavax for my booster jab after two jabs of astra zeneca, as i had a bad reaction on first jab. aged 70 years

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