COVID variant family expands

Since the Omicron variant of SARS-CoV-2 emerged in late 2021, it has spawned a series of subvariants that have sparked global waves of infection. In the past few months, scientists have identified more than a dozen extra subvariants to watch. There are so many that they’re being called a swarm, or ‘variant soup’. BQ.1.1 (a descendant of BQ.1) and XBB seem to be rising to the top, possibly because they have many mutations in a key region of the viral spike protein called the receptor binding domain, which is required to infect cells.

Growing family: Illustration of the SARS-CoV-2 family tree from origin to the Omicron variant soup.

Source: NextStrain

The variants near you

In Europe and North America, SARS-CoV-2 variants in the BQ.1 family are rising quickly and are likely to drive infection waves as these regions enter winter. They are also a common ingredient of the variant soup in South Africa, Nigeria and elsewhere in Africa. XBB, by contrast, looks likely to dominate infections in Asia; it recently drove a wave of infections in Singapore.

Variant swarm: Bar chart showing the proportion of Omicron sublineages found in 8 locations worldwide.

Source: Moritz Gerstung, Cov-Spectrum.org and GISAID

Money worries for science students

Eighty-five per cent of graduate students who responded to a Nature survey are worried about the increasing cost of living, and 25% are concerned about their growing student debt. Forty-five per cent said that rising inflation could cause them to reconsider whether to continue their science studies. The survey involved more than 3,200 self-selected PhD and master’s students from around the world.

Results from Nature Careers survey about the money worries of graduate students.

How species suffer in heatwaves

Even a small temperature rise has a severe effect on animal mortality, and understanding this relationship is important for predicting the effects of heatwaves caused by climate change. A paper in Nature used published data to examine how changes in temperature affect the rate of biological processes, such as movement or metabolism, at permissive temperatures — those at which species function normally. They also looked at how higher, stressful temperatures affect the rate of heat failure (irreversible heat injuries that result in death). This graph shows that rising temperatures drive a very rapid increase in heat-failure rates in frogs and molluscs. These high sensitivities suggest that when there is no way to escape hot conditions, species can quickly succumb.

Figure 1