Umair Irfan
Former correspondent
Latest articles by Umair Irfan
AstraZeneca and the University of Oxford say their vaccine has up to 90 percent efficacy. But there’s a lot we still don’t know.
The first doses may begin rolling out next week.
The company is now seeking Food and Drug Administration approval.
What the latest Covid-19 vaccine announcements from AstraZeneca-Oxford, Pfizer-BioNTech, and Moderna can and can’t tell us.
The companies say their vaccine could begin distribution to high-risk people by mid-December.
Moderna says its vaccine is 95 percent effective. Here’s what you need to know.
Subtropical Storm Theta is now the 29th named storm of the season.
The results are promising, but they’re drawn from a very small number of infections.
More than 120,000 new Covid-19 cases in a single day: We should have seen this coming.
Why the presidential election matters so much for global action on climate change.