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A small percentage of people — called superspreaders — may be responsible for a large number of COVID-19 infections, research is starting to indicate.
Why it matters: While there's no method to detect who these people are before they infect others, there are ways to control behaviors that cause superspreading events — a key issue as states start to reopen, Axios' Eileen Drage O'Reilly writes.
The latest: Three recent studies by the London School of Hygiene & Tropical Medicine, Tel Aviv University and the Institute for Disease Modeling in Washington, which have not yet been peer-reviewed, came to similar conclusions: Roughly 10% of COVID-19 cases appear to have caused around 80% of new infections.
It reflects the law of the "vital few," where a small number (between 5% and 20%) are responsible for the majority of cases, says Eric Topol, executive vice president of Scripps Research.
"Superspreader events can sometimes give an outbreak a new trajectory or allow it to sustain itself in a way that it wouldn't" otherwise, Amesh Adalja, senior scholar at the Johns Hopkins Center for Health Security, tells Axios.
What's happening: Why some people are superspreaders remains unknown. The person's genetics, immune system, how much virus they shed, and their behavior (such as how they speak, if they wash their hands often, if they socialize with large groups) likely play a role.
Background: Different pathogens have different "reproductive numbers" (called R0 or R-naught), which is the average number of infections one person transmits. The R0 for the SARS-CoV-2 virus is thought to be between 2–3.
The bottom line: Understanding how superspreading works could help to fine-tune responses to the coronavirus pandemic — and curb it.
An experimental mini ecosystem. Photo: Warwick Allen/University of Canterbury
Invasive plants can interact differently with local insects and microbes in the soil, releasing more carbon dioxide into the atmosphere than native plants, according to new research in the journal Science.
Why it matters: The cycling of carbon between the land and atmosphere is a key process in the regulation of Earth's climate and global temperature. Understanding how — and how much — nonnative plants alter that carbon cycle is important for climate forecasting and efforts to address climate change.
What they did: Lauren Waller of the Bio-Protection Research Centre at Lincoln University in New Zealand and her colleagues created 160 experimental mini ecosystems.
What they found: In the mini ecosystems with "home" soil and without insects, there was no change in how much carbon dioxide was emitted when native and nonnative plants were compared.
Plant traits — the thickness and density of their leaves, for example — may play a role in attracting insects and speeding up the rate that bacteria and fungi decompose them, releasing CO2.
The big picture: A better understanding of how invasive plants drive ecosystems is important as proposed efforts to plant massive numbers of trees in places around the world are debated, says David Wardle, a professor of forest ecology at Nanyang Technical University in Singapore.
Illustration: Sarah Grillo/Axios
From predicting outbreaks to devising treatments, doctors are turning to AI in an effort to combat the COVID-19 pandemic, Axios' Bryan Walsh writes.
Why it matters: While machine learning algorithms were already becoming a part of health care, COVID-19 is likely to accelerate their adoption. But lack of data and testing time could hinder their effectiveness — for this pandemic, at least.
What's happening: Doctors were quick to employ AI tools in an effort to get ahead of what could be the worst pandemic in a century.
In trials, at least, AI has demonstrated a decent record of success, especially when it comes to rapidly diagnosing COVID-19 by interpreting medical scans.
The catch: Many of the AI diagnostic systems were developed before the pandemic and thus were trained on CT scans of other respiratory diseases like tuberculosis.
The bottom line: "AI will not be as useful for COVID as it is for the next pandemic," Rozita Dara, a computer scientist at the University of Guelph, told Science recently.
Masks probably slow the spread of COVID-19 (The Economist)
CRISPR for fast, at-home coronavirus testing (Emily Mullin — OneZero)
The U.S. is getting shorter (Alanna Mitchell — NYT)
International Science and Engineering Fair finalist Sonja Michaluk watches the fair's opening ceremony in her home lab. Photo courtesy of Sonja Michaluk
Modern high school science fair projects are a long way from model volcanoes — they can now feature DNA sequencing, 3D printers, and other technologies from the pages of scientific and technical journals.
Why it matters: Science fairs are the culmination of at least months of work for many high school students and can connect them to lifelong friends and opportunities.
For the first time in 70 years, the Regeneron International Science and Engineering Fair (ISEF) was held online last week.
"I’m impressed they kept the fair going considering the global situation," says Sonja Michaluk, a 17-year-old student from Titusville, New Jersey, who is a three-time ISEF finalist. "I think that’s incredible and it teaches us young scientists and engineers the importance of being nimble and adapting because if we are going to solve the world’s problems we need those skills."
What to watch: If the pandemic continues to keep students out of labs this year, Ajmera expects they may instead plumb big datasets or explore computational problems. And she says she's interested in seeing how the pandemic inspires next year's projects.
Go deeper: You can watch ISEF's programming here until June 5.