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A diver takes a selfie with a larval cusk-eel

Marine biologist Jeff Milisen and larval cusk-eel friend.Jeff Milisen

See our ocean’s tiniest deep-sea creatures

A collaboration between underwater photographers and marine biologists is revealing the secret lives of our oceans’ tiniest animals. Every night, larval fish travel from the deep sea’s inky void towards the surface, where photographers snap stunning images of the delicate creatures. Normally, marine biologists see these animals only after they’ve been funneled through collection devices that often squash their fragile bodies into goo. Some scientists say the images, paired with DNA from collected larvae, have the potential to revolutionize the study of larval fishes’ behavior and anatomy. “The photographs can open up an entirely new research area to understand why they have these features and what they use them for,” says marine biologist Luiz Rocha.

New York Times | 8 min read

Reference: Ichthyology & Herpetology paper

COVID-19 coronavirus update

Why side effects are so hard to investigate

Countries have made halting efforts to respond to very rare cases of blood clots and severe allergic reactions in people who had a COVID-19 vaccine. The situation illustrates how fiendishly challenging it is to prove that an ‘adverse event’ following immunization was caused by the vaccine itself. Establishing causality can take years, especially for extremely rare side effects. Better surveillance systems that collect adverse-event data might help.

Nature | 8 min read

Coronavirus research highlights: 1-minute reads

Read more about these studies in Nature’s continuously updated selection of the must-read papers and preprints.

Vaccinating adults protects unvaccinated kids too

Vaccinating many people against SARS-CoV-2 could stall infection rates, even among unvaccinated children in the same community. Researchers looked at 223 Israeli communities in which older people had been widely vaccinated with the Pfizer–BioNTech vaccine. The infection risk among children under 16 dropped proportionally to the percentage of adults who had been vaccinated.

(Reference: medRxiv preprint — not peer reviewed)

Variants spur multi-talented antibody response

Antibodies from people infected with the 501Y.V2 coronavirus variant (also called B.1.351), first identified in South Africa, are also effective against previously circulating variants when tested in a laboratory dish. This implies that updated vaccines against 501Y.V2 could also protect against earlier coronavirus variants.

(Reference: Nature paper)

Real-world evidence that vaccines stop infection

A full vaccination reduces risk of SARS-CoV-2 infection by roughly 90%, and a single dose is 80% effective, according to a study of US nurses, firefighters and other front-line workers. Study participants received either the Moderna or Pfizer–BioNTech vaccines. The researchers caution that because very few participants became infected after vaccination, it’s difficult to state the vaccines’ effectiveness against infection with high precision. Clinical trials already showed that the two mRNA-based vaccines are highly effective at protecting people from getting COVID-19, the disease caused by SARS-CoV-2.

(Reference: Morbidity and Mortality Weekly Report paper)

Antibodies last for months — if you have them

A study of more than 9,500 people in Wuhan, China — once the epicentre of COVID-19 — found that only 7% of the population had been infected with SARS-CoV-2, of whom more than 80% had had no symptoms. Around 40% of the infected people produced neutralizing antibodies that could be detected for the entire 9-month study period. The researchers conclude that most people in Wuhan are still susceptible to SARS-CoV-2 infection, and that a mass-vaccination campaign is needed to achieve herd immunity.

(Reference: The Lancet paper)

Older people are at higher risk of getting COVID twice

Natural infection with SARS-CoV-2 protects against reinfection in most people — but this protection is significantly weaker in those aged 65 years or older. Researchers analysed millions of coronavirus test results in Denmark and found that, at about 6 months after initial infection, protection against repeat infection was approximately 80%, with no significant difference in reinfection rates between men and women. But this protection was reduced to 47% for those aged 65 years or older.

(Reference: The Lancet paper)

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

Notable quotable

“Put simply, the game has changed, and a successful global rollout of current vaccines by itself is no longer a guarantee of victory.”

Eight members of the Lancet COVID-19 Commission Taskforce on Public Health call for leaders to pursue public-health measures that will deliver “maximum suppression” of SARS-CoV-2. (The Conversation | 7 min read)

Features & opinion

4 year old Evie walks up a set of stone steps in the garden followed by her father and mother

Evie Lewis with her parents, Elliot and Janell. Evie receives a dose of a genetic therapy every few months to treat spinal muscular atrophy.Credit: Kim Raff for Nature

Hope for Huntington’s

A class of drugs that silence the effects of faulty genes could help to tackle brain diseases — but a halted clinical trial has hindered progress. Antisense oligonucleotides (ASOs) are short strings of DNA or RNA that are designed to cling to particular sequences of RNA made by faulty genes, and to rebalance the levels of proteins they produce — boosting missing proteins or quashing faulty ones. At the end of last month, a large phase III trial using an ASO treat Huntington’s disease was abruptly halted because the benefit of the drug to participants did not outweigh the risks. But researchers and people with Huntington’s, as well as more-common neurodegenerative conditions such as Parkinson’s and Alzheimer’s, remain hopeful about the promise that ASOs have shown in other diseases.

Nature | 12 min read

Dive in head-first to master English

Italian-speaker Lia Paola Zambetti recommends total immersion to fellow scientists taking on the challenge of learning English. She advises re-reading your favourite books (in English this time), going to the theatre, listening to news reports and seeking out fellow language-learners to share frustrations. “And when everything seems terrible and you can’t get your message across and frustration mounts like a wave, remember you are not the only one,” she writes. “Generations of students went in with broken English and came out at the other end with a thesis and a degree. It does get better.”

Nature | 7 min read

Relax to grow more hair

Researchers have found a stress hormone in mice that signals through skin cells to repress the activation of hair-follicle stem cells. When this signalling was blocked, the mice grew hair again. Molecular biologist Rui Yi digs deeply into what this research reveals about the mechanism of stress-based hair loss.

Nature News & Views | 7 min read

Reference: Nature paper

Quote of the day

“Every step we have taken since this journey began six years ago has been uncharted territory in the history of aircraft.”

Engineer Bob Balaram, who is leading NASA’s project to fly the first helicopter on another world, responds to the news that the Ingenuity helicopter has safely detached from the Perseverance rover. (ABC News)

Read more: A month on Mars: what NASA’s Perseverance rover has found so far (Nature | 6 min read)