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Three black and white cows in a field.

Livestock farming is one factor driving a rise in methane emissions.Credit: Lou Benoist/AFP/Getty

Atmospheric methane levels at all time high

Global methane emissions have risen nearly 10% over the past 2 decades, resulting in record-high levels of the powerful greenhouse gas. Atmospheric concentrations of the gas — 1,875 parts per billion last year — are now more than 2.5 times above pre-industrial levels. Emissions have been mostly driven by agriculture and the natural-gas industry. Increasing red-meat consumption propelled a 12% increase in emissions from agriculture in 2017 alone. “People may joke, but cows and other ruminants burp as much methane as the oil and gas industry,” says Earth-systems researcher Robert Jackson.

Nature | 3 minutes

Reference: Environmental Research Letters paper & Earth System Science Data paper

US cancels student-visa rule change

The US government has backed off of a visa rule change that put international students at risk of deportation if all their classes were taught online. The government agreed to rescind the change after it was sued by Harvard and the Massachusetts Institute of Technology. The issue had thrown the futures of more than one million foreign students — presently facing visa delays and pandemic-related travel restrictions — into doubt. Some students had already been turned away at US airports because of the rule.

The Wall Street Journal (paywall) | 7 min read or BBC | 4 min read

COVID-19 coronavirus update

Medical syringe is seen with Moderna company logo

Jakub Porzycki/NurPhoto via Getty

Moderna vaccine sparks an immune response

US biotechnology company Moderna’s messenger-RNA-based vaccine is safe, and provoked immune responses in all 45 healthy volunteers in its early-stage trial. The news might be familiar — the firm preliminarily announced its findings in a May press release. Now the results have been published in a peer-reviewed paper, with further details. “The hallmark of a vaccine is one that can actually mimic natural infection and induce the kind of response that you would get with natural infection. And it looks like, at least in this limited, small number of individuals, that is exactly what’s happening,” said Anthony Fauci, director of the National Institute for Allergy and Infectious Diseases, the branch of the US National Institutes of Health that conducted the trial. The vaccine will proceed to further clinical trials (it’s too soon to say whether it actually works).

STAT | 6 min read

Reference: The New England Journal of Medicine paper

Coronavirus research highlights: 1-minute reads

Autopsies point the finger at immune response

An autopsy-based study of 11 people who died from COVID-19 shows a mismatch between viral hotspots in the body and sites of inflammation and organ damage. This suggests that immune responses, rather than the virus itself, are responsible for death. The survey of 37 anatomical sites, including the lungs, found that some tissues harboured the virus but were not inflamed, whereas others were damaged but did not contain high levels of SARS-CoV-2.

Reference: medRxiv preprint (not yet peer reviewed)

In Spain, one million hidden asymptomatic cases

Europe’s largest effort to identify people who have been infected by the new coronavirus has found that roughly one-third of them did not show symptoms. Researchers tested more than 61,000 people from randomly selected households across Spain for SARS-CoV-2 antibodies. Nationwide, some 5% of people tested positive, of which around 1 in 3 were asymptomatic. On the basis of their results, the researchers estimate that roughly one million infected people could have gone undetected because they did not show symptoms.

Reference: Lancet paper

Frequent testing is key to reopening campuses

Researchers modelled the effect of a variety of testing strategies on the number of infections that would arise among 5,000 students during an 80-day semester, assuming that 5 new cases would be imported each week, each infected student would infect 2.5 others and those who tested positive would be isolated. Testing students every 2 days with a rapid and relatively cheap test would keep infections to around 135 over the semester, and cost US$470 per student per term. However, testing only weekly would result in an explosive growth in infections.

Reference: medRxiv preprint (not yet peer reviewed)

Anatomy of a superspreading event

Mobile-phone and credit-card data helped to identify hundreds of coronavirus infections linked to a fast-moving outbreak that began in the popular Itaewon nightclub district in Seoul. Researchers identified more than 60,000 people who had visited the area after it reopened on 30 April. More than 40,000 were tested and 246 were infected — including several that were 3, 4 or even 5 steps along the transmission chain from club-goers.

Reference: Emerging Infectious Diseases paper

Virus might have reached the United States in December

Models suggest that, in California and New York, SARS-CoV-2 might have begun circulating as early as December 2019. Infections spread across the country from late January to early March but were largely undetected. Researchers analysed air traffic, commuting patterns and other data to understand how and when the coronavirus took hold.

Reference: medRxiv preprint (not yet peer reviewed)

Get more of Nature’s continuously updated selection of the must-read papers and preprints on COVID-19.

Notable quotable

“The only valid reason to change released guidelines is new information and new science — not politics.”

The administration of US President Donald Trump is subverting sound public health guidelines and putting lives at risk, say four former directors of the US Centers for Disease Control and Prevention. (The Washington Post | 7 min read)

Features & opinion

How to decarbonize conference travel

The COVID-19 pandemic has forced us to rethink what constitutes necessary travel — which could be a very good thing, argue climate scientist Milan Klöwer and three colleagues. Their calculations show that biennials, regional hubs and virtual attendance could slash emissions from big meetings by up to 90%.

Nature | 10 min read

Shrink the footprint. Stacked bar chart shows the percent of emissions if locational or virtual changes are made to conference.

Source: M. Klöwer https://doi.org/10.5281/zenodo.3553784 (2019)

3 tonnes per scientist

The 28,000 delegates to the Fall Meeting of the American Geophysical Union travelled 285 million kilometres there and back — almost twice the distance between Earth and the Sun — emitting, on average, the same amount of CO2 as the city of Edinburgh does every week.

Get to grips with Gödel

Logician Kurt Gödel’s incompleteness theorems crushed the dream of a consistent set of basic axioms on which the foundations of mathematics could be built, and ushered in a world of unanswerable questions. Science writer Natalie Wolchover explains how Gödel “pulled off arguably one of the most stunning intellectual achievements in history” — and how mathematicians continue to come to grips with the consequences.

Quanta | 8 min read

Quote of the day

“The world has now witnessed the compression of 6 years of work into 6 months.”

Penny Heaton, the director of vaccine development at The Bill and Melinda Gates Foundation, ponders the promising results of Moderna’s phase 1 trial and the rest of the COVID-19 vaccine-development multiverse. (The New England Journal of Medicine | 9 in read)