Prof Baker has a range of public health research interests, with a particular focus on infectious diseases, environmental health and housing and has published widely in these areas.
As a member of the Ministry of Health's Covid-19 technical advisory group, he strongly advocated for eliminating the virus and keeping it out of the country. His commentary helped inform the government's decision for a national lockdown.
"I guess it symbolises the fact that the population approach that we all practice - and it's a big team of us doing this - really can make a difference, I think, particularly when the country is confronted with a new poorly-understood threat like the Covid-19 pandemic," Prof Baker said.
He said the critical moment for New Zealand was back in March when the country was following the influenza pandemic model, which was about mitigation and flattening the curve, and New Zealand changed direction at the last possible moment towards an elimination approach.
"We're still the only country in the world to have a written elimination strategy that we published, and I think it guided our response since then."
Prof Baker said "a big moment" for him was when a paper he co-authored on the elimination approach was published on the British Medical Journal on December 23.
"We really looked at the evidence from across the globe including New Zealand and what we concluded is that the elimination strategy not only protects the health of people, but also protects economies and we've seen better outcomes for countries like New Zealand, Australia, China and Taiwan that have really eliminated the virus or had that as our goal ..."
Internationally, Prof Baker is a member of the World Health Organisation Regional Verification Commission for Measles and Rubella Elimination and the Australian National Health and Medical Research Council's Centre for Research Excellence on Integrated Systems for Epidemic Response.
He also received the HRC Liley Medal in 2013 and the Prime Minister's Science Prize in 2014.
