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Research mice

More than 60% of the animals used for science across the European Union in 2017 were mice.Credit: Whitney Hayward/Portland Press Herald/Getty

Tough EU animal-research rules show effect

The use of animals in scientific research seems to be declining in the European Union. The drop follows the introduction seven years ago of legislation designed to reduce the use of animals in research and minimize their suffering. The first report on the state of animal research in the EU since the change says that 9.39 million animals were used for scientific purposes in 2017, compared with 9.59 million in 2015.

Nature | 3 min read

Popular preprint servers face closure

Preprint repositories such as IndiaRxiv, ArabiXiv, AfricArxiv and INA-Rxiv (from Indonesia) boost the visibility of regional science, but finding cash to run them is proving difficult. Some discipline-specific repositories, such as EarthArXiv and MarXiv (for marine-conservation science), are also struggling. At issue are new fees introduced by the non-profit Center for Open Science, based in the United States, which hosts 26 such repositories.

Nature | 5 min read

COVID-19 coronavirus outbreak

Models suggest cases are going undetected

• Some researchers in China are unhappy with the name announced for the new coronavirus, SARS-CoV-2. The name points to similarities between the evolutionary history of the new virus and that of the virus that causes severe acute respiratory syndrome (SARS). But some scientists worry that the public will make incorrect assumptions about the similarity of the diseases caused by the two viruses. (Nature | continuously updated)

• Epidemiologists are concerned that cases of the new coronavirus might be going undetected in some places. One model of the virus’s spread, based on flight data, identified 30 countries at high risk of an outbreak. But several of those countries, including Thailand, Vietnam, Cambodia and Malaysia, have reported fewer cases than the model predicts. Indonesia, another country at risk, has yet to report a single case. (Nature | 5 min read)

• There are four vaccine candidates in development for SARS-CoV-2, says World Health Organization virologist Marie-Paule Kieny. “It’s likely that there will be one or two that will go into human trials in about three to four months from now,” she said. “However, it would take at least 12 to 18 months for a vaccine to become available for wider use.” Doctors in China are also testing a combination of two HIV drugs — lopinavir and ritonavir — as well as a drug called remdesivir, which was originally developed to treat the Ebola virus. (New Scientist | 3 min read)

In this three-minute guide to how scientists are fighting COVID-19, discover the fields of research that are crucial to keeping outbreaks under control: epidemiology, virology and biomedical science. (Nature | 3 min video)

Notable quotable

“The specifics of each virus are important, but so is an overarching question: what do you do when large numbers of people arrive wanting care for suspected infections of an unfamiliar disease?”

Infectious-disease physician Nahid Bhadelia reflects on lessons for hospitals learned from the SARS, H1N1 swine flu and Ebola epidemics. (Nature)

Features & opinion

A man rides a horse through rainforest in the Talamanca mountains

A tropical forest in the Bribri Indigenous region of Costa Rica.Credit: Ivan Kashinsky/Panos

Adopt a carbon tax to protect tropical forests

There is a quick, cheap way to lower carbon emissions and protect the more than three-quarters of species that live in the tropics: reduce tropical deforestation. To pay for it, an economist, a conservationist and the environment ministers of Colombia and Costa Rica argue for a levy on fossil fuels. Their analysis shows that, if 12 other countries with tropical forests roll out a carbon tax similar to Colombia’s, they could raise US$1.8 billion each year between them to invest in natural habitats that benefit the climate.

Nature | 10 min read

Irreproducibility is not a sign of failure

The upside of irreproducibility can be found in attempt to measure the precise value of the constant of gravitation (G) — which is still uncertain despite numerous experiments spanning three centuries. When results in the science of measurement cannot be reproduced, argue metrologists Martin Milton and Antonio Possolo, it’s a sign of the scientific method at work — and an opportunity to promote public awareness of the research process.

Questions in biomedicine and the social sciences do not reduce cleanly to the determination of a fundamental constant of nature. But metrology reminds us that irreproducibility should not automatically be seen as a sign of failure, argues a Nature editorial. It can also be an indication that it’s time to rethink our assumptions.

Nature Physics | 9 min read & Nature | 4 min read

Correspondence: your letters to Nature

Romania needs its astronomers back

The Romanian Academy’s outdated regulations discourage researchers who have pursued careers abroad from returning home, writes astronomer Ovidiu Vaduvescu.

China: clamp down on violations of wildlife trade ban

In response to the coronavirus outbreak, China has temporarily banned the transport and sale of wild animals. But people are dodging the law all too easily, write four researchers — creating a disaster for global biodiversity, animal welfare and human health.

A permanent ban on wildlife trade might not work in China

Outlawing the sale of wildlife risks fuelling an intractable, uncontrolled and highly priced illegal trade, write four researchers. The demand in China for animal parts and game meat needs to be managed through initiatives that discourage consumption, such as education campaigns that aim to discredit ingrained cultural beliefs.

Correspondence is published every week in Nature. For more info on writing one yourself, please see the guidance on nature.com. (Your feedback on this newsletter is always welcome at briefing@nature.com, but won’t be considered for publication in Nature.)

Quote of the day

“I have had six decades of experience on both sides of the gun and have been wounded several times by gunfire.”

Former US surgeon-general Richard Carmona — who has also been in the special forces, a homicide detective, a SWAT team member, a combat medic, a paramedic, a registered nurse and a trauma surgeon — writes a heartfelt summation in a special edition of Current Trauma Reports on gun violence.