In the science fiction movie "The Wandering Earth," artificial intelligence system "Moss" is able to explore all solutions to save the Earth in just a few seconds.

This miraculous scene is gradually transitioning from science fiction to reality. The ultra-high-performance optoelectronic chip proposed by the research team at Tsinghua University adopts a new architecture of optoelectronic fusion, which is disruptive to existing chip technologies, the team told the Global Times on Wednesday.

The technology not only opens up a new path for this future technology to become part of daily life, but also provides inspiration for the integration of other future high-performance technologies such as quantum computing and in-memory computing with current electronic information systems.

The results, titled "Purely Analog Optoelectronic Chips for High-Speed Visual Tasks," had been published in the recent issue of the journal "Nature."

In 1965, Gordon Moore, one of the founders of Intel, proposed "Moore's Law," which has influenced the chip industry for over half a century. It predicts that the number of transistors on integrated circuits will double approximately every two years.

The semiconductor field has prospered for decades based on Moore's Law, and "chips" have become an important engine for humanity's entry into the era of digital intelligence. However, as transistor sizes approach their physical limits, Moore's Law has slowed down or even faced failure in the past decade. How to build a new generation of computing architecture and establish a "new" order of chips in the era of artificial intelligence has been a frontier hotspot of international concern.

To address this challenge, a joint research team from Tsinghua University, including Academician Dai Qionghai from the Department of Automation, Assistant Professor Wu Jiamin, Associate Professor Fang Lu from the Department of Electronic Engineering, and Associate Researcher Qiao Fei, proposed a new computing architecture that "breaks free" from Moore's Law: optoelectronic analog chips. In practical tests for visual tasks, the computing power of these chips reached over 3,000 times that of current high-performance commercial chips.

From a physical perspective, optoelectronic chips are based on a disruptive technology that is different from existing chip technologies, the research team explained in an interview with the Global Times on Wednesday. They noted that, at current stage, their work is focused on intelligent visual tasks, and they are also conducting further exploration to see if the new technology can achieve tasks of the same or even higher complexity as current chips, such as large language models.

In this small chip, the Tsinghua University research team creatively proposed an optoelectronic deep fusion computing framework. Starting from the most fundamental physical principles, it combines optical computing based on electromagnetic wave propagation in space with pure analog electronic computing based on Kirchhoff's law. It "breaks free" from the physical bottlenecks of data conversion speed, accuracy, and power consumption that constrain traditional chip architectures, and overcomes three international challenges: large-scale computing unit integration, efficient nonlinearity, and high-speed optoelectronic interfaces.

In the demonstrated intelligent visual scene tests in the paper, the system-level computing power of the optoelectronic fusion chip was thousands of times higher than that of existing high-performance chip architectures. However, such astonishing computing power is just one of the many advantages of this chip. In the intelligent visual tasks and traffic scene calculations demonstrated by the research team, the system-level energy efficiency (the number of operations that can be performed per unit of energy) of the optoelectronic fusion chip reached 74.8 Peta-OPS/W, which is over 4 million times that of current high-performance chips. In other words, the amount of electricity that can power existing chips for one hour can power this chip for over 500 years.

One key factor currently limiting chip integration limits is the heat dissipation problem caused by high density. The optoelectronic fusion chip, which operates at ultra-low power consumption, will greatly improve the chip's heat dissipation problem and bring all-round breakthroughs to the future chip design. Furthermore, the minimum linewidth of the chip's optical part is only in the hundreds of nanometers, while the circuit part uses 180 nanometers Complementary metal-oxide-semiconductor technology, achieving a performance improvement of multiple orders of magnitude compared to 7 nanometers process high-performance chips. At the same time, the materials used are simple and easily obtainable, and the cost is only a fraction of the latter.

Will the emergence of this cutting-edge chip technology help China achieve a "overtaking on the curve" in chip research and development? In response to this question, the research team told the Global Times that the research and development competition in the traditional chip technology field is becoming increasingly fierce, and facing international challenges such as the slowing down of Moore's Law, the world is seeking new computing architectures. It can indeed be understood as a kind of "curve" opportunity. Whether we can achieve "curve overtaking" depends on the joint efforts and ecological construction of all sectors. We are also working towards this goal.

A special review of this research, invited by the journal Nature, pointed out that the appearance of this chip may allow the new generation of computing architecture which will be integrated into daily life much earlier than expected. Academician Dai Qionghai, one of the corresponding authors of the paper, stated, "Developing a new computing architecture for the era of artificial intelligence is a summit, but truly implementing the new architecture in real life to solve major national and livelihood needs is a more important challenge and our responsibility."

The tourism phenomenon triggered by Harbin, the ice city in Northeast China's Heilongjiang Province, shows no sign of abating and most recently its popularity has led to a fierce competition among tourism authorities in several Chinese cities, as they strive to leverage the internet's potential to convert online engagement into real tourist footfall.

Starting from January 9, the official Douyin account of the Department of Culture and Tourism of Henan Province has seen an increase in the number of videos being posted, with 20 to 30 clips being released per day and a total of 112 in four days, enthusiastically showcasing its cultural and tourism resources. By posting videos such as "Shaolin Kung Fu" and "mutton stewed noodles" to show off its local cuisine, the account gained nearly one million followers within just a few days.

In January, North China's Shanxi and Central China's Henan provinces announced their partnership in tourism, achieving mutual exemption of admission tickets for 114 A-level scenic spots in six cities.

While culture and tourism authorities in Shanxi and Henan provinces are boasting their enriched tourism resources on social media, East China's Shandong Province, famous for being the birthplace of Confucius and the location of the famous Taishan Mountain and the Yellow River estuary, has also attracted much online attention.

The Department of Culture and Tourism in North China's Hebei Province changed their short video official name overnight, from "Hebei Tourism" to "Hebei Cultural and Tourism." This alteration was prompted by the fierce online competition to attract tourists, resulting in the phrase "cultural and tourism" gaining significant popularity across various social media platforms.

More interesting is that the video of the head of culture and tourism in Harbin's Acheng district dancing with performers from Harbin Ice-Snow World, the world's largest theme park of its kind, on short video platforms, has entertained millions of netizens.

These diligent efforts made by the local head of culture and tourism in Harbin to attract tourists to the city were joined by netizens across the country as they playfully boasted about the exceptional skills possessed by their own heads of culture and tourism bureaus, all in an effort to achieve similar success in their own cities.

Netizens from Southwest China's Sichuan Province, known for its giant panda bases, jokingly claimed that their head of local culture and tourism bureau has the extraordinary ability to "give birth to" giant pandas. While, netizens from Central China's Hunan Province proudly boasted that their head of cultural and tourism can devour a staggering 50 kilograms of red peppers. Hunan Province is renowned for its diverse pepper varieties and spicy cuisine, which locals take great pride in.

Netizens from Southwest China's Yunnan Province went as far as bragging that their head of cultural and tourism can consume three kilos of raw wild mushrooms. Yunnan is famous for its different types of wild mushrooms, some of which can be poisonous if not cooked properly.

With the rapid proliferation of social media, Harbin has swiftly become the most coveted tourist destination in the country. Recognizing this trend, cultural and tourism authorities aim to harness the power of the internet to transform online engagement into actual tourist visits.

Cities surrounding Harbin have also attempted to take advantage of the huge tourist flow brought with Harbin by frequently uploaded interesting videos.

Tourism in Harbin hasn't become popular overnight. It is a result of the long-term promotion of ice and snow sports in Northeast China, reflecting the booming popularity of China's ice and snow tourism, Jiang Yiyi, deputy head of the School of Leisure Sports and Tourism at Beijing Sport University, told the Global Times on Sunday.

Jiang believes it might be difficult to reproduce the popularity of Harbin tourism. Its popularity and the booming Zibo barbecue phenomenon in 2023 are the results of unintentional efforts. However, both places have achieved good interaction with the tourists.

These two major tourism events in China and the popularity of a grassroots basketball tournament known as Village BA are not only developed based on the tourism resources in these regions, but also achieved by actively grafting them with local culture, Jiang noted.

Industry observers noted that the key to turning one-time booming tourism into a persistent trend lies in the continuous cultivation of a pleasant destination to visit and fostering a warm-hearted hospitality.

In the beginning of this winter, Harbin has effectively addressed tourists' complaints regarding the organization and services of Harbin Ice-Snow World, as well as overcharging by local restaurants. This crisis management has left a positive impression of the city. Harbin has also taken the initiative to provide considerate services to tourists, media reports said. For example, numerous free warm and comfortable rest stations have been established at major tourist attractions, which have been well-received by visitors.

Both last year's Zibo barbecue and this year's ice and snow fever reflect the fast recovery of China's tourism industry. As winter, the traditional tourism off-season, draws new tourism fever, these events signal the fast tourism development in China, Jiang noted.

From the Adora Magic City's completion of its maiden commercial voyage on Sunday to Chinese shipbuilders obtaining the most orders from global clients in 2023, China's high-end manufacturing sector, represented by the steadily progressing shipbuilding industry, has become a new driving force in the country's economic development. 

The Adora Magic City, China's first domestically built large cruise ship, completed its maiden commercial voyage on Sunday after taking more than 3,000 tourists from 16 countries and regions for a seven-day trip to destinations in South Korea and Japan. 

China has been advancing its shipbuilding technology especially in high-value added segments with strong international competiveness. The ability to build ultra-large container ships and use green fuels is also leading the world, Zheng Ping, chief analyst with industry news portal chineseport.cn, told the Global Times on Sunday. 

Last year, Chinese shipyards won the highest number of global orders, with deliveries as far off as 2028, according to media reports. 

The delivery dates for Guangzhou Shipyard International Co run into 2027 and 2028, as fleet operators worldwide are attracted by the company's strengths in green production and environmental protection, said Li Hao, an official from the company, as China Media Group (CMG) reported on Saturday.

More than 60 percent of the company's on-hand orders are methanol-powered dual-fuel ships or LNG- fired (liquefied natural gas) () dual-fuel models. Compared with conventional container ships, ultra-large container ships powered by dual-fuel sources can reduce carbon emissions by 20 percent, nitrogen oxide emissions by 85 percent and sulfur emissions by 99 percent, CMG reported.

In 2023, Hudong-Zhonghua Shipbuilding Group delivered 17 vessels, which was 106 percent of the annual plan. The number of medium- and high-end vessels exceeded 90 percent of the total deliveries, the company said in a statement it sent to the Global Times earlier. Hudong-Zhonghua is now building 16 LNG vessels simultaneously, and it plans to deliver nearly 50 LNG carriers in the next five years.

China has basically closed the technological gap with South Korea in building high-value added ships, Zheng said, and China's shipbuilding boom will persist this year.   

In 2023, Chinese shipbuilders won the most new orders worldwide for a total of 24.46 million compensated gross tons (CGT), 59 percent of the total, data from UK-based Clarksons Research showed. South Korea was second for the third consecutive year with 10.01 million CGT. 

China's shipbuilding industry is striving to advance its high-quality development through intelligent and green technology. 

The intelligent transformation has also boosted the efficiency of shipbuilding, which is traditionally a labor-intensive process. Through intelligent transformation, the entire workshop for building a ro-ro passenger ship with more than 20,000 square meters can be reduced from 200 people to 50 people by integrating more automation and robotics technology, according to the CMG report. 

Intelligent ports are becoming popular in China with the expanding utilization of autonomous trucks and other types of smart equipment, Zheng said. 

He said that the domestic industry is still in the early stages of smart development, and  more emerging technologies will be  integrated into future manufacturing.  

From January to November 2023, China completed ships totaling 38.09 million deadweight tons (dwt), up 12.3 percent year-on-year, according to the Ministry of Industry and Information Technology. 

New orders rose 63.8 percent to 68.45 million dwt, and orders on hand totaled 134.09 million dwt as of the end of November.

Situated in Li county in Northwest China's Gansu Province, commonly seen as the birthplace of China's Qin Dynasty (221BC-206BC) culture, a local archaeological site has recently been found to have been a large-scale architectural complex used for sacrificial ceremonies.

The Sijiaoping Ruins are located on an excavated flat platform on the top of a mountain in the county. The ancient man-made platform covers an area of 28,000 square meters and was encircled by a rammed earth wall. At the center of the site is a square platform with annexes on either side of it.

Archaeologist Wang Meng told the Global Times that the entire configuration of the site delivers a "sense of grandeur and solemnity." The symmetrical and square designs are often seen in many ancient Chinese designs, especially in high-grade and royal architecture. The "symmetrical" design is particularly common as it embodies Chinese people's belief in harmony.

Exquisitely made ancient objects like eaves tiles, also known as wadang, decorated with cloud patterns and tiles featuring a rope pattern were found scattered inside the ruins. Those artifacts gave experts the clues they needed to narrow down the specific time period of the site.

Hou Hongwei, the lead expert of the Sijiaoping archaeological project, said that the tiles and eaves tiles were "very similar" to the ones discovered in the mausoleum of the Qin Dynasty Emperor Qin Shi Huang.

"According to the production techniques and decorative details on those unearthed building materials, we can preliminarily identify the Sijiaoping site as a high-level ceremonial building from the Qin Dynasty," the expert said.

Besides the visible structures, the Qin ceremonial site also contained a half-crypt space. The space was covered with tiles on both the walls and floor. Experts predict it was once a water pool. The pool was most likely closely tied to the Qin people's "belief in the virtues of water," Hou remarked.
While the function of the Sijiaoping ruins is only recently identified, their importance had already been noticed by scholars when the site was first discovered in 2019.

The Sijiaoping site was discovered near another site, the Dabaozi Mountain site, which is also in Gansu Province. The Dabaozi Mountain site is a tomb cluster covering some 18 square kilometers.

Archaeologist Xue Ruiming told the Global Times that the Dabaozi Mountain site reveals that Li county was once the "center of the Qin regime during the Spring and Autumn Period (770BC-476BC)."

The Sijiaoping architectural complex was established after the Qin Kingdom was unified. The Sijiaoping site is the only "systematic" and complete building complex from the time period discovered to date. It demonstrates the burial and ritual traditions of the Qin.

"The close connections between the two sites help our contextual analysis of the Qin Dynasty's burial and ritual traditions. Such a discovery contributes to scholar's analysis of early Chinese sacrificial traditions," said Xue.

Unlike Western ceremonial buildings that often carry a religious mission, ancient ritual buildings in China reflect the country's ancient philosophy.

Their unique shapes and configurations during different historical periods were manifestations of ancient Chinese people's perspectives on people-to-people relations, the dynamic between human beings and nature and ethics.

Compared to the Qin Dynasty's "solemn" style, ceremonial buildings of the Xia Dynasty (c.2070BC-c.1600BC) were more pragmatic as they hosted collective activities. During the Eastern Zhou Dynasty (770BC-256BC), the design of ritual buildings paid closer attention to the ease of transportation.

When things heat up, spinning electrons go their separate ways.

Warming one end of a strip of platinum shuttles electrons around according to their spin, a quantum property that makes them behave as if they are twirling around. Known as the spin Nernst effect, the newly detected phenomenon was the only one in a cadre of related spin effects that hadn’t previously been spotted, researchers report online September 11 in Nature Materials.

“The last missing piece in the puzzle was spin Nernst and that’s why we set out to search for this,” says study coauthor Sebastian Goennenwein, a physicist at the Technical University of Dresden in Germany.
The effect and its brethren — with names like the spin Hall effect, the spin Seebeck effect and the spin Peltier effect — allow scientists to create flows of electron spins, or spin currents. Such research could lead to smaller and more efficient electronic gadgets that use electrons’ spins to store and transmit information instead of electric charge, a technique known as “spintronics.”

In the spin Nernst effect, named after Nobel laureate chemist Walther Nernst, heating one end of a metal causes electrons to flow toward the other end, bouncing around inside the material as they go. Within certain materials, that bouncing has a preferred direction: Electrons with spins pointing up (as if twirling counterclockwise) go to the right and electrons with spins pointing down (as if twirling clockwise) go to the left, creating an overall spin current. Although the effect had been predicted, no one had yet observed it.

Finding evidence of the effect required disentangling it from other heat- and charge-related effects that occur in materials. To do so, the researchers coupled the platinum to a layer of a magnetic insulator, a material known as yttrium iron garnet. Then, they altered the direction of the insulator’s magnetization, which changed whether the spin current could flow through the insulator. That change slightly altered a voltage measured along the strip of platinum. The scientists measured how this voltage changed with the direction of the magnetization to isolate the fingerprints of the spin Nernst effect.

“The measurement was a tour de force; the measurement was ridiculously hard,” says physicist Joseph Heremans of Ohio State University in Columbus, who was not involved with the research. The effect could help scientists to better understand materials that may be useful for building spintronic devices, he says. “It’s really a new set of eyes on the physics of what’s going on inside these devices.”

A relative of the spin Nernst effect called the spin Hall effect is much studied for its potential use in spintronic devices. In the spin Hall effect, an electric field pushes electrons through a material, and the particles veer off to the left and right depending on their spin. The spin Nernst effect relies on the same basic physics, but uses heat instead of an electric field to get the particles moving.
“It’s a beautiful experiment. It shows very nicely the spin Nernst effect,” says physicist Greg Fuchs of Cornell University. “It beautifully unifies our understanding of the interrelation between charge, heat and spin transport.”

MINNEAPOLIS — To destroy plastic, caterpillars go with their gut bacteria.

Caterpillars that nibble through polyethylene plastic cultivate a diverse community of digestive bacteria that process the plastic, researchers reported November 13 at the annual meeting of the Society of Environmental Toxicology and Chemistry North America. Dousing old plastic in a similar mix of bacteria might speed the breakdown of the persistent pollutant.

Polyethylene is widely used to make plastic bags and other packaging materials, but it hangs around in landfills for decades, perhaps even centuries. Recently, scientists identified several species of caterpillars that appear to eat and digest the plastic, breaking it down. But dumping old shopping bags into a den of caterpillars isn’t really a practical large-scale strategy for getting rid of the plastic. So to figure out the insects’ secret, researchers fed polyethylene to the larvae of pantry moths, Plodia interpunctella, and then looked at the bacteria in the caterpillars’ guts.
Caterpillars that ate a control diet of bran and wheat had guts mostly dominated by Turicibacter, a group of bacteria commonly found in animals’ digestive tracts. But the caterpillars that munched on the plastic had a much more diverse native microbial community. In particular, they had high levels of a few types of bacteria: Tepidimonas, Pseudomonas, Rhizobiales and Methylobacteriaceae.

Some of these bacteria have been shown to colonize and help degrade plastics in the ocean, says study coauthor Anisha Navlekar of Texas Tech University in Lubbock, so it makes sense that the microorganisms also appear to be helping the caterpillars break down plastics.

A new kind of artificial cartilage, made with the same kind of fiber that fortifies bulletproof vests, is proving stronger than others.

The fabricated material mimics the stiffness, toughness and water content of natural cartilage, researchers report in the Jan. 4 Advanced Materials. This synthetic tissue could replace the cartilage in a person’s body that naturally wears down and heals poorly (SN: 8/11/12, p. 22), alleviating joint pain and potentially sparing many people from having to undergo joint replacement surgery.
Scientists have been trying to fashion artificial cartilage for decades, says Kara Spiller, a biomedical engineer at Drexel University in Philadelphia not involved in the work. But earlier materials were either weaker than the real thing or didn’t pack enough water to transport nutrients to surrounding cells.

The new material is a polymer mixture called a hydrogel that’s mostly water and contains nanoversions of the aramid fibers used to make bulletproof vests. Nicholas Kotov, a chemist at the University of Michigan in Ann Arbor, and his colleagues tested how well their material held its shape when squeezed or stretched, and how easily it was broken. Both versions of the hydrogel — one, about 70 percent water; the other, about 92 percent water — either matched or exceeded the stiffness and toughness of real cartilage.

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The new material has “a lot of different possibilities,” Spiller says. “The biggest market is going to be osteoarthritis patients, because most patients with osteoarthritis have no damage to the bone, just damage to the cartilage.” Many of the 30 million adults in the United States who suffer from osteoarthritis undergo whole knee or hip replacements. If doctors could simply replace worn down cartilage with this material, that could lower the risk of surgical complication. “That would be really huge,” Spiller says.
This kind of hydrogel “could also be used for all sorts of sports injuries, where you have damaged tendons or ligaments, [or] even for back pain,” she adds.

It remains to be seen how well this material can integrate into a person’s body, says Benjamin Wiley, a chemist at Duke University not involved in the work. Researchers still need to make sure it can anchor to bone and doesn’t irritate surrounding tissue.

When the 2017 Great American Eclipse hit totality and the sky went dark, bees noticed.

Microphones in flower patches at 11 sites in the path of the eclipse picked up the buzzing sounds of bees flying among blooms before and after totality. But those sounds were noticeably absent during the full solar blackout, a new study finds.

Dimming light and some summer cooling during the onset of the eclipse didn’t appear to make a difference to the bees. But the deeper darkness of totality did, researchers report October 10 in the Annals of the Entomological Society of America. At the time of totality, the change in buzzing was abrupt, says study coauthor and ecologist Candace Galen of the University of Missouri in Columbia.
The recordings come from citizen scientists, mostly school classes, setting out small microphones at two spots in Oregon, one in Idaho and eight in Missouri. Often when bees went silent at the peak of the eclipse, Galen says, “you can hear the people in the background going ‘ooo,’ ‘ahh’ or clapping.”
There’s no entirely reliable way (yet) of telling what kinds of bees were doing the buzzing, based only on their sounds, Galen says. She estimates that the Missouri sites had a lot of bumblebees, while the western sites had more of the tinier, temperature-fussy Megachile bees.
More western samples, with the fussier bees, might have let researchers see an effect on the insects of temperatures dropping by at least 10 degrees Celsius during the eclipse. The temperature plunge in the Missouri summer just “made things feel a little more comfortable,” Galen says.

This study of buzz recordings gives the first formal data published on bees during a solar eclipse, as far as Galen knows. “Insects are remarkably neglected,” she says. “Everybody wants to know what their dog and cat are doing during the eclipse, but they don’t think about the flea.”

Vinita Surukan knew the mosquitoes were trouble. They attacked her in swarms, biting through her clothes as she worked to collect rubber tree sap near her village in Sabah, the northern state of Malaysia. The 30-year-old woman described the situation as nearly unbearable. But she needed the job.

There were few alternatives in her village surrounded by fragments of forest reserves and larger swaths of farms, oil palm plantations and rubber tree estates. So she endured until a week of high fever and vomiting forced her to stop.
The night of July 23, Surukan was trying to sleep off her fever when the clinic she visited earlier in the day called with results: Her blood was teeming with malaria parasites, about a million in each drop. Her family rushed her to the town hospital where she received intravenous antimalarial drugs before being transferred to a city hospital equipped to treat severe malaria. The drugs cleared most of the parasites, and the lucky woman was smiling by morning.

Malaria has terrorized humans for millennia, its fevers carved into our earliest writing on ancient Sumerian clay tablets from Mesopotamia. In 2016, four species of human malaria parasites, which are spread by mosquito from person to person, infected more than 210 million people worldwide, killing almost 450,000. The deadliest species, Plasmodium falciparum, causes most of the infections.

But Surukan’s malaria was different. Hers was not a human malaria parasite. She had P. knowlesi, which infects several monkey species. The same parasite had recently infected two other people in Surukan’s village — a man who hunts in the forest and a teenager. Surukan suspects that her parasites came from the monkeys that live in the forest bordering the rubber tree estate where she worked. Some villagers quit working there after hearing of Surukan’s illness.

Monkey malaria, discovered in the early 1900s, became a public health concern only in the last 15 years. Before that, scientists thought it was extremely rare for monkey malaria parasites, of which there are at least 30 species, to infect humans.
Yet since 2008, Malaysia has reported more than 15,000 cases of P. knowlesi infection and about 50 deaths. Infections in 2017 alone hit 3,600.
People infected with monkey malaria are found across Southeast Asia near forests with wild monkeys. In 2017, another species of monkey malaria parasite, P. cynomolgi, was found in five Malaysians and 13 Cambodians. And by 2018, at least 19 travelers to the region, mostly Europeans, had brought monkey malaria back to their home countries.

The rise of monkey malaria in Malaysia is closely tied to rapid deforestation, says Kimberly Fornace, an epidemiologist at the London School of Hygiene and Tropical Medicine. After testing blood samples of nearly 2,000 people from areas in Sabah with various levels of deforestation, she found that people staying or working near cut forests were more likely than people living away from forests to have P. knowlesi infections, she and colleagues reported in June in PLOS Neglected Tropical Diseases. Stepping over felled trees, humans move closer to the monkeys and the parasite-carrying mosquitoes that thrive in cleared forests.
It’s out there
There’s no feasible way to treat wild monkeys for an infection that they show no signs of. “That’s the problem with P. knowlesi,” says Singapore-based infectious disease specialist Fe Espino, a director of the Asia Pacific Malaria Elimination Network.

In 2015, the World Health Organization set a goal for 2030: to stop malaria transmission in at least 35 of the 91 malaria-endemic countries. WHO targets the four human malaria parasites: P. falciparum, P. vivax, P. malariae and P. ovale. Monkey malaria is excluded from the campaign because the agency regards it as an animal disease that has not been shown to transmit among humans.

But as countries reduce human malaria, they will eventually have to deal with monkey malaria, Espino says, echoing an opinion widely shared by monkey malaria scientists.

“Something nasty” could emerge from the pool of malaria parasites in monkeys, says malariologist Richard Culleton of Nagasaki University in Japan. Culleton studies the genetics of human and monkey malaria. Malaria parasites can mutate quickly — possibly into new types that can more easily infect humans (SN: 9/6/14, p. 9). To Culleton, the monkey malaria reservoir “is like a black box. Things come flying out of it occasionally and you don’t know what’s coming next.”
Malaysia is very close to reaching the WHO target of human malaria elimination. In 2017, only 85 people there were infected with human malaria. But that success feels hollow as monkey malaria gains a foothold. And while monkey malaria has swelled into a public health threat only in Malaysia, the same could happen in other parts of Southeast Asia and beyond. Even in southeastern Brazil, where human malaria was eliminated 50 years ago, the P. simium malaria parasite that resides in howler monkeys caused outbreaks in humans in 2015 and 2016.

From tool to threat
In the late 1800s, scientists discovered the Plasmodium parasite and its Anopheles mosquito carriers. Humans retaliated by draining marshes to stop mosquito breeding and spraying insecticides over whole communities. Governments and militaries pursued antimalarial drugs as the disease claimed countless soldiers during the two World Wars.

Scientists soon found malaria parasites in birds, rodents, apes and monkeys. To the researchers, the parasites found in monkeys were a tool for testing antimalarial drugs, not a threat. An accident, however, showed otherwise.
In 1960, biologist Don Eyles had been studying the monkey malaria P. cynomolgi at a National Institutes of Health lab in Memphis, Tenn., when he fell ill with malarial fevers. He had been infected with the parasites found in his research monkeys. His team quickly confirmed that the malaria parasites in his monkeys could be carried by mosquitoes to humans. Suddenly, monkey malaria was not just a tool; it was an animal disease that could naturally infect humans.
The news shook WHO, McWilson Warren said in a 2005 interview recorded by the Office of NIH History. Warren, a parasitologist, had been Eyles’ colleague. Five years before Eyles became infected, WHO had launched the Global Malaria Eradication Programme. Banking on insecticides and antimalarial drugs, the agency had aimed to end all malaria transmissions outside of Africa. A monkey malaria that easily infects humans would sink the program because there would be no way to treat all the monkeys.

A team of American scientists, including Eyles and Warren, traveled to Malaysia — then the Federation of Malaya — where the P. cynomolgi parasites that infected Eyles came from. Funded by NIH, the scientists worked with colleagues from the Institute of Medical Research in Kuala Lumpur, established in 1900 by the British to study tropical diseases.

From 1961 to 1965, the researchers discovered five new species of monkey malaria parasites and about two dozen mosquito species that carry the parasites. But the researchers did not find any human infections. Then, in 1965, an American surveyor became infected with P. knowlesi after spending several nights camping on a hill about 160 kilometers inland from Kuala Lumpur.

Warren surveyed the forested area where the infected American had camped. The hill sat beside a meandering river. Monkeys and gibbons, a type of ape, lived on the hill and in adjacent forests. The closest house was about two kilometers away. Warren sampled the blood of four monkeys and more than 1,100 villagers around the hill; he collected mosquitoes too.

He found P. knowlesi parasites in the monkeys, but none among the villagers. Only one mosquito species, A. maculatus, appeared capable of transmitting malaria between monkeys and humans, but Warren deemed its numbers too low to matter. He concluded that monkey malaria stayed in the forests and rarely ever spilled into humans.

With those results, NIH ended the monkey malaria project, Warren said, and the Institute of Medical Research in Kuala Lumpur returned to its primary focus: human malaria, dengue and other mosquito-borne diseases. Monkey malaria was struck off the list of public health concerns.

Wake-up call
P. knowlesi landed back in the spotlight in 2004, with a report in the Lancet by malariologist Balbir Singh and his team. The group had found 120 people infected over two years in southern Malaysian Borneo. The patients were mostly indigenous people who lived near forests. Clinicians initially had checked the patients’ blood samples under microscopes — the standard test — and diagnosed the parasites as human malaria. But when Singh, of Universiti Malaysia Sarawak, applied molecular tools that identify parasite species by their DNA, he revealed that all the samples were P. knowlesi. Monkey malaria was breaking out of the diminishing forests.

By 2018, P. knowlesi had infected humans in all Southeast Asian countries except for East Timor. Singapore, declared malaria free in 1982, reported that six soldiers were infected with P. knowlesi from wild monkeys in a forest reserve. The parasite also turned up in almost 380 out of 3,700 visitors to health clinics in North Sumatra, Indonesia, an area that is close to being deemed free of human malaria.
Many scientists now recognize P. knowlesi as the fifth malaria parasite species that can naturally infect humans. It is also the only one to multiply in the blood every 24 hours, and it can kill if treatment is delayed. People pick up P. knowlesi parasites from long-tailed macaques, pig-tailed macaques and Mitred leaf monkeys. These monkeys range across Southeast Asia. So far, malaria parasites have been found in monkeys near or in forests, but rarely in monkeys in towns or cities.

Scientists propose several reasons for the recent rise in monkey malaria infections, but two stand out: improvement in malaria detection and forest loss.

Malaysia, for instance, finds more monkey malaria cases than other Southeast Asian countries because it added molecular diagnostic tools in 2009. Other countries use only microscopy for detection, says Rose Nani Mudin, who heads the vectorborne disease sector at Malaysia’s Ministry of Health. Since 2008, annual monkey malaria cases in Malaysia have climbed tenfold, even as human malaria cases have plummeted. “Maybe there is a genuine increase in [monkey malaria] cases. But with strengthening of surveillance, of course you would detect more cases,” she says.

Data collected by Malaysia’s malaria surveillance system have also revealed strong links between infection risk and deforestation. Fornace, the epidemiologist, examined the underlying drivers of monkey malaria in Surukan’s home state of Sabah. Fornace mapped monkey malaria cases in 405 villages, based on patient records from 2008 to 2012. Satellite data showed changes in forested areas around those villages. The villages most likely to report monkey malaria infections were those that had cut more than 8 percent of their surrounding forests within the last five years, she and colleagues reported in 2016 in Emerging Infectious Diseases.
Fornace’s team went into the field for a follow-up study, published in June in PLOS Neglected Tropical Diseases. The team collected blood samples from almost 2,000 people in two areas in Sabah and checked for current and past malaria infection. People who farmed or worked in plantations near forests had at least a 63 percent higher risk of P. knowlesi infection, and — like in the 2016 study — forests and cleared areas escalated risk of infection.

“It feels almost like P. knowlesi follows deforestation,” Fornace says. Several years after a forest is cut back, nearby communities “get a peak of P. knowlesi.”

Today, the hill where the American surveyor camped in 1965 is a small island in a sea of oil palm estates. From 2000 to 2012, Malaysia cleared a total amount of forest equaling 14.4 percent of its land area, more than any other country, according to a study published in 2013 in Science. A study in 2013 in PLOS ONE used satellite images to show that in 2009, only one-fifth of Malaysian Borneo was intact forest. Almost one-fourth of all forest there had been logged, regrown and logged many times over.

Since 2008, oil palm acreage in Malaysian Borneo has increased from 2.08 million hectares to 3.1 million, according to the Malaysian Palm Oil Board. In Malaysia, the four states hit hardest by deforestation — Sabah, Sarawak, Kelantan and Pahang — report 95 percent of the country’s P. knowlesi cases.
Fornace thinks deforestation and the ecological changes that come with it are the main drivers of monkey malaria’s rise in Malaysia. She has seen long-tailed macaques spend more time in farms and near houses after their home forests were being logged. Macaques thrive near human communities where food is abundant and predators stay out. Parasite-carrying mosquitoes breed in puddles made by farming and logging vehicles.

Where monkeys go, mosquitoes follow. Indra Vythilingam, a parasitologist at University of Malaya in Kuala Lumpur, studied human malaria in indigenous communities in the early 1990s. Back then, she rarely found A. cracens, the mosquito species that carries monkey malaria in Peninsular Malaysia. But in 2007, that species made up over 60 percent of mosquitoes collected at forest edges and in orchards, she reported in 2012 in Malaria Journal. “It’s so much easier to find them” now, she says.

As Fornace points out, “P. knowlesi is a really good example of how a disease can emerge and change” as land use changes. She recommends that when big projects are evaluated for their impact on the economy and the environment, human health should be considered as well.

What to expect
While P. knowlesi cases are climbing in Malaysia, scientists have found no evidence that P. knowlesi transmits directly from human to mosquito to human (though many suspect it happens, albeit inefficiently).
Following a review by experts in 2017, WHO continues to exclude P. knowlesi from its malaria elimination efforts. Rabindra Abeyasinghe, a tropical medicine specialist who coordinates WHO malaria control in the western Pacific region, says the agency will reconsider P. knowlesi as human malaria if there is new evidence to show that the parasite transmits within human communities.

In Malaysia last year, only one person died from human malaria, but P. knowlesi killed 11. “We don’t want that to happen, which is why [P. knowlesi] is our priority even though it is not in the elimination program,” says Rose Nani Mudin from the country’s Ministry of Health.

Unable to do much with the monkeys in the trees, Malaysian health officers focus on the people most likely to be infected with P. knowlesi. Programs raise awareness of monkey malaria and aim to reduce mosquitoes around houses. New mosquito-control methods are needed, however, because conventional methods like insecticide-treated bed nets do not work for monkey malaria mosquitoes that bite outdoors around dusk.

Fighting malaria is like playing chess against an opponent that counters every good move we make, says Culleton in Japan. Malaria parasites can mutate quickly and “go away and hide in places and come out again.” Against malaria, he says, “we can never let our guard down.”

This article appears in the November 10, 2018 Science News with the headline, “The Next Malaria Menace: Deforestation brings monkeys and humans close enough to share an age-old disease.”

Editor’s note: This story was updated on November 6, 2018 to correct the WHO’s position on monkey malaria. The agency excludes monkey malaria parasites from its malaria eradication goals, not because those particular parasites rarely infect humans, but because the parasites have not been shown to transmit among humans.

The United States is poised to take a powerful economic hit from climate change over the next century. Heat waves, wildfires, extreme weather events and rising sea levels could cost the country hundreds of billions of dollars in lost labor, reduced crop yields, health problems and crumbling infrastructure.

A report authored by hundreds of U.S. climate scientists from 13 federal agencies presents a stark picture of the country’s fate due to climate change. The Fourth National Climate Assessment, released November 23, predicts the U.S. economy will shrink by as much as 10 percent by the end of the century if global warming continues apace.
A separate report released November 27 by the United Nations Environment Programme reveals that in 2017, global emissions of carbon dioxide — a major driver of warming — rose for the first time in three years. That suggests that the nations that promised to curb emissions as part of the historic 2015 Paris agreement are falling short (SN: 1/9/16, p. 6).

It’s unclear what effect, if any, the reports will have on the U.S. government’s strategy on dealing with climate change and its consequences. President Donald Trump has previously announced he would withdraw the United States from the Paris agreement (SN Online: 6/1/17). And on November 26, Trump told reporters that he had read “some of” his scientists’ report. “It’s fine,” he said. But when it comes to the dire predictions of economic losses, he added, “I don’t believe it.”

The National Climate Assessments are mandated by Congress and produced every four years, focusing on the risks of climate change specifically to the United States. What’s different about the new report compared with previous editions is its precision about the risks to different parts of the U.S. economy, putting a price tag on the potential losses in agriculture, trade and energy generation.

To put a dollar value on bad air quality or worsening heat waves, for instance, scientists try to assess the measurable impacts of those issues — for example, the number of days of work or school missed, or the number of doctors’ visits triggered (SN Online: 10/14/18).
The more-than-1,600-page report includes detailed examinations of the effects of climate change on the country’s different regions. People living in the northeastern United States, for example, will be among the hardest hit by deaths due to poor air quality and temperature extremes by the end of the century. Labor losses in the southeastern United States are the highest of all regions, as are projected damages to roads and bridges, the report found.

Meanwhile, the Midwest will see the highest increase in premature deaths from increased amounts of ozone. And the Southwest, which includes California in these analyses, will suffer from extreme heat, drought and an increase in future cases of the mosquito-borne West Nile virus.

The report estimates that cumulatively the country will spend $23 billion responding to wildfires by the end of the century, even if greenhouse gas emissions are modestly reduced. The Southwest will bear the brunt of that impact, spending $13 billion dollars.

The report also details the many ways in which climate change is already hurting the country economically. For example, three storms that made landfall during the 2017 Atlantic hurricane season — Harvey, Irma and Maria — together cost the United States at least $265 billion, according to the National Oceanic and Atmospheric Administration.

By continuing on its current trajectory of greenhouse gas emissions, the “business-as-usual” scenario, the United States will see the greatest losses, the assessments concludes. However, the report also considers climate impacts in an alternate future, in which the world has taken modest actions to curb greenhouse emissions, including using more carbon-neutral fuels and the growth of technological innovations to remove carbon dioxide from the atmosphere (SN Online: 10/20/18).