Science’s COVID-19 reporting is supported by the Heising-Simons Foundation.

On 6 January, gastroenterologist Leolin Katsidzira received a troubling message from his colleague James Gita Hakim, a heart specialist and noted HIV/AIDS researcher. Hakim, chair of the department of medicine at the University of Zimbabwe, had fallen sick and had tested positive for COVID-19. He was admitted to a hospital in Harare 10 days later and moved to an intensive care unit (ICU) after his condition deteriorated. He died on 26 January.

It is a crushing loss to Zimbabwean medicine, Katsidzira says. “Don’t forget: We have had a huge brain drain. So people like James are people who keep the system going,” he adds. Scientists around the world mourned Hakim as well. He was “a unique research leader, a brilliant clinical scientist and mentor, humble, welcoming and empowering,” wrote Melanie Abas, a collaborator at King’s College London.

But Hakim’s death also highlights a stark reality in the global response to the coronavirus pandemic. Countries in Europe, Asia, and the Americas have administered more than 175 million shots to protect people against COVID-19 since December 2020, with most countries giving priority to medical workers. But not a single country in sub-Saharan Africa has started immunizations—South Africa will be the first, this week—leaving health care workers dying in places where they are scarce to begin with...

...According to the World Health Organization (WHO), three-quarters of all vaccinations so far have happened in 10 countries that account for 60% of global gross domestic product; 130 countries have yet to administer a single dose. “I don’t know why there isn’t a massive clamor to do something about that,” says Gavin Yamey of Duke University’s Global Health Institute. “The world is on the brink of a catastrophic moral failure,” Tedros Adhanom Ghebreyesus, the Ethiopian-born director-general of WHO, said in January...

...Beyond the moral argument, there are sound economic and public health reasons to close the gap. Vaccinating those most at risk around the world would drive down hospitalizations and deaths everywhere sooner, allowing societies to reopen and economies to recover. It could also help reduce circulation of the virus globally, lowering the risk of new virus variants emerging...

Kizzmekia Corbett, an immunologist at the US National Institutes of Health (NIH), is one of the scientists who in early 2020 helped to develop an mRNA-based vaccine for COVID-19. Developed in collaboration with biotech firm Moderna of Cambridge, Massachusetts, the vaccine is now being distributed across the United States and elsewhere. And Corbett is taking on another challenge: tempering vaccine hesitancy by talking about COVID-19 science in communities of colour.

Corbett is one of many Black scientists and doctors who are doing this outreach, often virtually, in their free time. Researchers say it’s necessary to make scientific knowledge accessible in public forums, to ease health disparities.

In the United States, COVID-19 has affected Black, Native American and Latino American people at higher rates than white people, for reasons rooted in racism and historical segregation. At the same time, people in these groups are more wary of COVID-19 vaccines. In a December survey by the US Centers for Disease Control and Prevention, 46% of Black adults said they probably would not get vaccinated against the coronavirus SARS-CoV-2, compared with 30% of white respondents...

...Before the COVID-19 outbreak, Corbett was part of a team at the NIH in Bethesda, Maryland, and elsewhere, that was designing vaccines for other coronaviruses in collaboration with Moderna. The scientists’ mRNA technology delivers a piece of genetic code to a person’s cells to create immune-stimulating virus proteins. When the outbreak began, the team mobilized to quickly identify the SARS-CoV-2 genetic sequence it would need to make a vaccine for COVID-19, which Moderna then produced...

...What was your role in designing a vaccine for SARS-CoV-2, and what was that like?

My contribution was helping to design the vaccine, leading the preclinical studies that informed the Phase I clinical trial and designing assays used for testing of clinical trial samples.

The quest in early January 2020 was to gear up. We started ordering all the things that we needed around animal experiments. We mapped out a plan. I started assigning roles to team members.

If you want to go fast in a pandemic, then messenger RNA (mRNA) is a shoo-in. It can be manufactured very quickly in very vast quantities, and it’s plug and play in that you can essentially just swap out the protein once you have the system down. We collaborated with Moderna so we could get the system down pat...

A new analysis traces the story of the draft genome’s impact on genomics since 2001, linking its effects on publications, drug approvals and understanding of disease.

The 20th anniversary of the publication of the first draft of the human genome1,2 offers an opportunity to track how the project has empowered research into the genetic roots of human disease, changed drug discovery and helped to revise the idea of the gene itself.

Here we distil these impacts and trends. We combined several data sets to quantify the different types of genetic element that have been discovered and that generated publications, and how the pattern of discovery and publishing has changed over the years. Our analysis linked together data including 38,546 RNA transcripts; around 1 million single nucleotide polymorphisms (SNPs); 1,660 human diseases with documented genetic roots; 7,712 approved and experimental pharmaceuticals; and 704,515 scientific publications between 1900 and 2017 (see Supplementary information; SI ).

The results highlight how the Human Genome Project (HGP), with its comprehensive list of protein-coding genes, spurred a new era of elucidating the function of the non-coding portion of the genome and paved the way for therapeutic developments. Crucially, the results track the emergence of a systems-level view of biology alongside the conventional single-gene perspective, as researchers mapped the interactions between cellular building blocks (see ‘No jump for big teams’)...

...These connections offer a snapshot of the evolution of the research landscape before and after the HGP. It shows an intense focus on a small number of ‘superstar’ protein-coding genes, potentially to the detriment of interesting work that could be done on others. There has been a pivot towards non-protein-coding sections of the genome, and to understanding interactions between genetic material and proteins. And drug discovery has been grounded in just a few protein targets.

Some of these trends are familiar to biologists, but to quantify and visualize them is to consider them anew...

...Superstar genes

The popular perception is that the HGP marked the start of the intensive search for protein-coding genes. In fact, the 2001 draft HGP paper signalled the end of a decades-long hunt1,2. Indeed, evidence for the first protein-coding gene emerged in 1902, with the discovery of the hormone secretin4 (SCT gene), 50 years before the structure of DNA was uncovered, and 75 years before genome sequencing became commonplace. Our analysis shows that, between the start of the HGP in 1990 and its completion in 2003 (after the draft was published in 2001), the number of discovered (or ‘annotated’) human genes grew drastically...

...Intense study is, of course, justified for genes that have profound biological importance. A good example is TP53 — it is crucial to cell growth and death, and leads to cancer when inactivated or altered. Variations in this gene are found in more than 50% of tumour sequences. It is mentioned in 9,232 publications between 1976 and 2017 (see SI, Fig. S4)...

...Drug discovery

Before about the 1980s, drugs were found largely by serendipity. Their molecular and protein targets were usually unknown. Until 2001, the probability of knowing all of a drug’s protein targets was less than 50% in any given year. The HGP changed this. Now, the targets are known for almost all drugs licensed in the United States each year (see ‘Twenty years of junk, stars and drugs: Drug targets’)...

The naturally occurring isotope 230Th (half-life, 75,380 years) is a well known tool for constraining time information in marine sediments and seawater. Its versatility is due to its production in seawater at an exactly known and constant rate from dissolved uranium. The uranium content of oxic seawater in turn is proportional to salinity, behaving conservatively on timescales of at least 800,000 years12. The amount of 230Th produced in the water column at a given location is therefore a deterministic function of the amount of overlying sea salt13,14.

Once produced by decay, 230Th is known to be highly particle reactive and removed to the sea floor close to its site of production within years to decades15, even in very low-particle-flux environments, such as the Pacific Gyres16. One should therefore expect that a substantial amount of meteoric ice with a salinity of virtually zero would be seen as a reduction in the amount of deposited excess 230Th (230Thex). This reduction must be proportional to the amount of displaced seawater. A 1,000-m-thick ice shelf over a seafloor of 2,000-m depth would reduce the available 230Thex sediment inventory by half. If the water underlying the ice shelf had a reduced salinity as well, this would further reduce the 230Thex inventory correspondingly. For a water column consisting of only meteoric ice and freshwater, no 230Thex should be present.

Here we test this hypothesis on a set of sediment cores from the Arctic Ocean that cover the recent glacials; how many glacials exactly is a matter of ongoing debate17,18,19,20,21. We contribute two new high-resolution records of 230Th, together with uranium isotopes and elemental composition, and compare them to other 230Thex records to test our hypothesis and map the spatial and temporal extent of a shelf ice with underlying freshwater in the Arctic Ocean.

Figure 1 reveals two intervals with low or absent 230Thex observed across the entire Arctic and into the Norwegian and Greenland seas (hereafter, assumed to represent the Nordic seas). These minima occur in olive-grey to greyish sand-rich siliciclastic sediments that are virtually barren of autochthonous calcareous microfossils. They are mainly characterized by increased terrigenous coarse fraction, reduced bioturbation, and some laminations (see Methods for more details on lithology).

a, Map displaying water depths 125 ?m; green, bottom axis), sand content (orange, top axis) and the stable carbon (pink, bottom axis) and oxygen (blue, top axis) isotope composition of N. pachyderma in PS72/396-3, for the uppermost complete 40 cm of this sedimentary section. j, Photograph of a Cibicides lobatulus subsp. grossa sample, obtained from PS72/396-5 (78 cm depth); scale bar, 500 ?m. In g, h, occurrences of the large shelf species Cibicides lobatulus subsp. grossa (j; see Methods) are indicated by stars. Blue shading indicates the two major low-230Thex intervals discussed in the text. Error bars denote one standard deviation precision; details on analytical reproducibility in Extended Data Table 2. The precision of the stable isotope measurements has been found to be better than 0.06‰ and 0.08‰ (absolute) for ?13C and ?18O, respectively, over a one-year period. PDB, Pee Dee belemnite.

Our observations go beyond confirming the presence of large ice shelves, because we see not only a substantial reduction of 230Thex at most sites in these intervals, but its almost complete absence, even below 2,500-m water depth. This implies that the water mass underlying the ice shelf was fresh, not saline, at least to this depth. This view is supported not only by 230Thex, but also by the virtual absence of calcium carbonate together with low values for sulfur, which originates in part from sea salt in typical marine sediments. For PS2185-3/6, PS2200-2/5, PS1533-3 and PS1235-2, the absence or reduction of cosmogenic 10Be for these intervals (and partly beyond) is confirmed as well32,33, which supports a permanent cover of the basin.

Combining the available evidence, we conclude that the Arctic-wide occurrence of thick shelf-ice in peak glacials could repeatedly lead to a blockage of the GSR overflow, causing freshening of the entire Arctic basin and the Nordic seas (Extended Data Fig. 5). Large amounts of isotopically lighter freshwater were stored in this ice-dammed system, influencing isotope records outside the Arctic on potentially very short timescales, and providing a mechanism for rapid release of freshwater. Sea-level reconstructions need to account for the possibility that not all isotopically light water was stored on land. So far, we found evidence of freshwater intervals in MIS 4 and—most probably—MIS 6. A shorter and less pronounced freshwater interval, seen only in selected cores with high sedimentation rates, and not observed in the Nordic seas so far, may have occurred in a part of MIS 2, ending around 14,900 years ago...

By taking fringe ideas mainstream, the former US president taught new and dangerous lessons about manipulating social and mass media.

For people around the world, the now-iconic images of a man in a horned headdress roaming the US Capitol during the 6 January insurrection came as a shock. For Kate Starbird, the images were frighteningly familiar. ‘QAnon Shaman’ — the online persona of Jacob Anthony Chansley, or Jake Angeli — is a known superspreader of conspiracy theories that her research group has been monitoring for years.

The storming of the Capitol was “this physical manifestation of all of these digital characters we’ve been studying”, says Starbird, a social scientist at the University of Washington in Seattle, who investigates the spread of disinformation on social media. “To see all of that come alive in real time was horrifying, but not surprising.”


The epic battle against coronavirus misinformation and conspiracy theories
Starbird is among a cadre of researchers in the United States and abroad who study the way disinformation and conspiracy theories take root and spread through social and mass media. As US president and a prolific tweeter, Republican Donald Trump turned their research upside down when he helped to push typically fringe theories into the mainstream — most recently by downplaying the coronavirus pandemic and promoting the unfounded claim that the US presidential election had been stolen from him.

With Trump out of office, this group of researchers is now working to make sense of the deluge of data that they’ve collected from platforms such as Twitter and Facebook. It’s been a lesson in modern populism: a world leader amplified once-obscure conspiracy theories, with each tweet and retweet strengthening the ideas and emboldening their supporters. Now, researchers are retooling to understand — and prepare for — what comes next...

...One debate in the conspiracy-theory research community is whether Trump has pushed more people into QAnon, or whether he just emboldened those who already believed. Polling suggests that QAnon adherents remain a small, if increasingly vocal, minority, says Joseph Uscinski, a political scientist at the University of Miami in Florida who has been tracking public support for several years...

...QAnon has clearly gained ground under Trump in recent years, says Joan Donovan, a disinformation researcher at Harvard University in Cambridge, Massachusetts. The activity that she and her team monitor online, as well as the real-world protests and political rallies taking place, add up to “a growing interest in or dedication to these ideas”, she argues...

...“Conspiracy theories are fundamentally a form of political propaganda,” says Quassim Cassam, a philosopher at the University of Warwick in Coventry, UK. Although Trump failed to overturn the election, Cassam says the former president was very successful at mobilizing his political base — and radicalizing the Republican Party...

The annual mean rate of growth of CO2 in a given year is the difference in concentration between the end of December and the start of January of that year. If used as an average for the globe, it would represent the sum of all CO2 added to, and removed from, the atmosphere during the year by human activities and by natural processes. There is a small amount of month-to-month variability in the CO2 concentration that may be caused by anomalies of the winds or weather systems arriving at Mauna Loa. This variability would not be representative of the underlying trend for the northern hemisphere which Mauna Loa is intended to represent. Therefore, we finalize our estimate for the annual mean growth rate of the previous year in March, by using the average of the most recent November-February months, corrected for the average seasonal cycle, as the trend value for January 1. Our estimate for the annual mean growth rate (based on the Mauna Loa data) is obtained by subtracting the same four-month average centered on the previous January 1. Preliminary values for the previous year are calculated in January and in February.

The estimated uncertainty in the Mauna Loa annual mean growth rate is 0.11 ppm/yr. This estimate is based on the standard deviation of the differences between monthly mean values measured independently by the Scripps Institution of Oceanography and by NOAA/ESRL. The annual growth rate measured at Mauna is not the same as the global growth rate, but it is quite similar. One standard deviation of the annual differences MLO minus global is 0.26 ppm/year.