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Coloured scanning electron micrograph of SARS-CoV-2 virus particles (yellow) emerging from the surface of a cell (blue).

Particles of SARS-CoV-2 (yellow; artificially coloured) emerge from a cell.Credit: National Institutes of Health/Science Photo Library

Natural COVID immunity might not last

Unvaccinated people who have been infected with SARS-CoV-2 are at risk of reinfection within a couple years, according to a model based on knowledge of SARS-CoV-2 and other coronaviruses. Researchers combined long-term data for ‘endemic’, or continually circulating, coronaviruses that can cause the common cold with genetic data from SARS-CoV-2 and the closely related coronaviruses SARS-CoV and MERS-CoV. The results suggest that the average reinfection risk rises from about 5% at 4 months after initial infection to 50% by 17 months. “Immunity is relatively short-lived,” says bioinformatician Jeffrey Townsend. “You should still get vaccinated even if you got infected.”

Nature | 4 min read

Fires in Australia hammered invertebrates

More than 14,000 invertebrate species, including insects, spiders and worms, lost habitat in the 2019–20 wildfires across Australia. At least one animal, the Banksia montana mealybug (Pseudococcus markharveyi) seems to have gone extinct in the fires. A report from the National Environmental Science Programme recommends that 60 species be added to Australia’s list of threatened invertebrates, almost doubling the number on the list. And those are “just the ones we know about”, says entomologist and arachnologist Jess Marsh — many more vulnerable species lack sufficient data to be listed.

The Guardian | 6 min read

Reference: National Environmental Science Programme report

Features & opinion

Why fossil-fuel subsidies are so hard to kill

Each year, governments around the world pour about half a trillion dollars into artificially lowering the price of fossil fuels — more than triple what renewables receive. Most countries have agreed this must end — the question is how. Decision-makers don't all agree on what constitutes a fossil-fuel subsidy: are we just talking about axing tax breaks for oil and gas companies and fixed prices for end users, or should we also consider what pollution and carbon emissions cost to society? Ultimately, say some analysts, the goal should be for governments to stop giving companies permission to extract fossil fuels at all.

Nature | 10 min read

Refugee scientists keep research hopes alive

Two non-profit organizations, the US Institute of International Education Council and the UK Council for At Risk Academics, support scientists driven out of their home countries. A theoretical nuclear physicist from Yemen and a chemist and an archaeologist from Syria share their trials and triumphs as they continue their research despite extraordinary conditions. “My advice to other refugee scientists is not to waste any time once you move to a new country. Start learning the native language as soon as possible,” says the chemist, who now lives in Turkey. “And don’t make the mistake we did: don’t wait for the situation to get better. Find ways to continue on an academic path.”

Nature | 10 min read

Three tests for the next NIH leader

The successor to Francis Collins at the US National Institutes of Health (NIH) will need to be steadfast, nimble and creative, argues a Nature editorial. The world’s largest biomedical research agency is at a pivotal time: its leader will have to guide biomedical research during and after the COVID-19 pandemic; deal with systemic racism and inequity in science; and navigate scientific cooperation with China. That is in addition to the core role of securing the agency’s budget, and being ever-more creative in making the case for supporting basic research.

Nature | 17 min read

A better way to make a mammoth

When geneticist George Church asked evolutionary biologist Victoria Herridge, a critic of mammoth de-extinction, to join the advisory board of his company aiming to do just that, she said no. “It was ethics, not feasibility, that was my main concern,” Herridge says. The company, Colossal, is driven by a real desire to help the world — “but reshaping the planet shouldn’t be left to a chosen few”, she writes. “Instead, Colossal, and all companies like it, should do something as radical for business as its plans are for the planet: actively involve the public in its research decisions.”

Nature | 5 min read

Image of the week

GIF of the irradiation experiment

Light unleashes ‘traveller’ molecules (shown here moving faster than actual speed) to scoot along track-like fibres.Credit: M. Samperi et al./Nature Chem.

Light prompts ‘traveller’ molecules (shown here moving faster than actual speed) embedded in a gel to scoot along track-like fibres — a journey that could lead to the development of new molecular-scale machines.

(Nature Research Highlight | 1 min read, Nature paywall)