For the past few months, the Omicron variant has been like an onion for scientists: they have had to peel back one layer at a time with scientific accuracy while the world first went into full panic mode and then came to declare the new “variant of concern” a possible game changer that could end the pandemic phase of SARS-CoV-2.

Now, two bouts of research on international travellers have added to the body of knowledge of Omicron and the best way forward in managing the disease.

One — published as correspondence in The Lancet — suggests that even with booster shots Omicron can break through, and the other — a preprint in Science of the Total Environment — suggests that testing wastewater on aircraft is a great way to carry out surveillance of a variant traversing the world...