Nurse manager Sue McGrady receives the Pfizer/BioNTech vaccine in Sydney, Australia, on February 22. | Toby Zerna/AP

Hilda Bastian on the most important pandemic vaccine in the pipeline and why we’re on track for annual booster shots.

When Hilda Bastian and I first caught up over Skype to talk about Covid-19 vaccines last autumn, she showed me the boxes and unfinished rooms in her new home in Victoria, Australia. She’d been so busy tracking the global vaccine effort, she hadn’t had time to settle in.

Bastian — an expert in analyzing clinical trial data, founding member of the Cochrane Collaboration, and a former National Institutes of Health official — has gone down rabbit holes before. There was the time she traveled the US on her own dime to research and take historical photos for a Wikipedia list of African American mathematicians.