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The Hindu
5 days ago
- Health
- The Hindu
Sir Ronald Ross and the mosquito link: how one nobel winning discovery changed the course of malaria control
Before Sir Ronald Ross's discovery in 1897, malaria was understood to be a disease caused by bad air ('mal aria,' meaning bad air). While the disease was recognised and feared for centuries, the underlying cause was not known. Understanding how malaria spreads: A scientific turning point On August 20, 1897, while working in Secunderabad, India, Ross dissected a mosquito that had fed on a malaria-infected patient. Inside its gut lining, he observed the presence of Plasmodium parasites—the microscopic organisms responsible for malaria. This observation provided the medical community with the first solid evidence that mosquitoes act as carriers of the disease. Although French military doctor Charles Laveran had identified Plasmodium in human blood in 1880, the method of transmission remained unclear. Ross, building on the ideas of physician Patrick Manson, confirmed that the malaria parasite requires a mosquito host to complete part of its life cycle before being passed to humans. Marking this discovery, Ross noted in his journal: 'This day relenting God Hath placed within my hand, A wondrous thing…' These words captured not only a breakthrough in understanding infectious disease but also a shift in how malaria prevention would be approached from then on. A scientific method grounded in observation and precision Ross conducted careful experiments using birds infected with Plasmodium relictum, an avian form of malaria. He allowed mosquitoes to feed on these birds and later dissected them at regular intervals. Over time, he found the parasites developing in the mosquito's stomach lining -- later forming what we now know as oocysts. This work revealed the external (or 'extrinsic') development of Plasmodium in the mosquito. Ross had traced the full transmission cycle, proving mosquitoes were not just incidental but a necessary host for the parasite. His work became the foundation of what we now call vector biology—the study of how insects and other organisms transmit diseases. The World Health Organization (WHO) acknowledges Ross's discovery as a pivotal moment in public health, reporting that it 'opened up a new vista for prevention and control of malaria' Changing how public health systems responded to malaria Ross's findings had a direct impact on how malaria was managed in India, Africa, and Southeast Asia. Once mosquitoes were identified as vectors, public health teams focused on controlling mosquito breeding: draining stagnant water, managing swamps, and later using insecticides like DDT. Ross went on to work in Sierra Leone and Mauritius, where he applied these principles in real-world malaria control efforts. He used mapping, statistics, and population data to track infection spread—techniques that are still used in disease surveillance today. In 1902, Ross received the Nobel Prize in Physiology or Medicine for his work. The citation read:'for his work on malaria, by which he has shown how it enters the organism and thereby has laid the foundation for successful research on this disease and methods of combating it.' His legacy Ross was also a prolific writer, poet, and advocate for medical education in the colonies. He pushed for more locally-run laboratories and for training Indian personnel in research methods, long before it became common practice. He also developed early mathematical models for how malaria spreads, laying the groundwork for what would become the Ross-Macdonald model—a widely used formula to estimate malaria transmission based on mosquito and human populations. The Centers for Disease Control and Prevention (CDC) notes that Ross's work, in collaboration with George Macdonald, led to the development of a mathematical model of mosquito-borne pathogen transmission . Over 125 years later, Ross's discovery continues to influence how we fight malaria. Vector control—like bed nets, mosquito repellents, and larvicide treatments—remains one of the most effective strategies to prevent the diseas .The WHO emphasises that controlling insect vectors has played an increasingly important role in reducing the burden of malaria since Ross's discovery . August 20 is now remembered as 'Mosquito Day' in his honor, especially in India. His field lab in Secunderabad has been turned into a memorial, and medical researchers still refer to his original drawings and writings. Sir Ronald Ross died in 1932. At the Liverpool School of Tropical Medicine, where he later taught, his epitaph reads: 'He gave to mankind an immense weapon against death.'
Chicago Tribune
6 days ago
- General
- Chicago Tribune
Today in History: EPA bans use of pesticide DDT
Today is Saturday, June 14, the 165th day of 2025. There are 200 days left in the year. This is Flag Day. Today in history: On June 14, 1972, the Environmental Protection Agency ordered a ban on domestic use of the pesticide DDT, to take effect at year's end. Also on this date: In 1775, the Continental Army, forerunner of the United States Army, was created by the Second Continental Congress. In 1777, the Second Continental Congress approved the design of the first 'stars and stripes' American flag. In 1846, a group of U.S. settlers in Sonoma proclaimed the breakaway state of the California Republic, declaring independence from Mexico. In 1919, British aviators John Alcock and Arthur Whitten Brown embarked on the first non-stop flight across the Atlantic Ocean. In 1940, German troops entered Paris during World War II; the same day, the Nazis transported their first prisoners to the Auschwitz concentration camp in German-occupied Poland. In 1943, the U.S. Supreme Court, in West Virginia State Board of Education v. Barnette, ruled 6-3 that public school students could not be forced to salute the flag of the United States or recite the Pledge of Allegiance. In 1954, President Dwight D. Eisenhower signed a bill adding the phrase 'under God' to the Pledge of Allegiance. In 1982, Argentine forces surrendered to British troops on the disputed Falkland Islands. In 1993, President Bill Clinton announced his nomination of Judge Ruth Bader Ginsburg to serve on the U.S. Supreme Court. In 2005, Michelle Wie, 15, became the first female player to qualify for an adult male U.S. Golf Association championship, tying for first place in a 36-hole U.S. Amateur Public Links sectional qualifying tournament. In 2017, fire ripped through the 24-story Grenfell Tower residential building in West London, killing 72 people. In 2018, a Justice Department watchdog report on the FBI's handling of the Hillary Clinton email probe criticized the FBI and its former director, James Comey, but did not find evidence that political bias tainted the investigation. Today's Birthdays: Actor Marla Gibbs is 94. U.S. President Donald Trump is 79. Olympic speed skating gold medalist Eric Heiden is 67. Jazz musician Marcus Miller is 66. Singer Boy George is 64. Tennis Hall of Famer Steffi Graf is 56. Classical pianist Lang Lang is 43. Actor J.R. Martinez is 42. Actor Lucy Hale is 36. Actor Daryl Sabara is 33. Rapper Gunna is 32.
Boston Globe
09-06-2025
- Politics
- Boston Globe
Frank Graham Jr., nature writer who updated ‘Silent Spring,' dies at 100
He added, 'I'd visit him in Maine, where he had a little island, and we'd be eating plants, and he'd also be picking spiders out of his kayak and identifying them.' Advertisement In addition to birds and insects, Mr. Graham wrote about threats to the environment. Ed Neal, the outdoors columnist for The San Francisco Examiner, described Mr. Graham's 1966 book, 'Disaster by Default: Politics and Water Pollution,' as 'a damning indictment of what industry and indifferent government have done to the nation's waterways.' Get Starting Point A guide through the most important stories of the morning, delivered Monday through Friday. Enter Email Sign Up In 1967, after the book was reviewed in Audubon, the magazine asked him to write about the progress, if any, of pesticide legislation and regulation in the United States since the publication of 'Silent Spring,' a devastating examination of the ecological effects of insecticides and pesticides including DDT. A year later, Audubon named him its field editor, a job he held until 2013. Advertisement Mr. Graham's three-part series about pesticides for the magazine persuaded Paul Brooks, Carson's editor at Houghton Mifflin, to sign him to write an update of 'Silent Spring.' The resulting Mr. Graham book, 'Since Silent Spring' (1970), described the years Carson spent researching and writing 'Silent Spring,' documented the attacks on her findings by agricultural and chemical companies and governmental interests, and chronicled the catastrophes caused by pesticides in the ensuing years. (Carson died in 1964.) Mr. Graham's book came out several months after the federal government announced steps it was taking to ban DDT, vindicating Carson's message. 'One cannot read this book and escape the fundamental point that today's environmental advocates are attempting to make,' Francis W. Sargent, a conservationist and moderate Republican who was elected governor of Massachusetts in 1970, wrote about 'Since Silent Spring' in The New York Times Book Review. 'Man's environment has become so complex and interrelated that any action that alters one aspect of the environment may have a potentially disastrous impact on man's health.' Looking back in 2012 in an Audubon article, Mr. Graham wrote that his book was one Carson 'should have written to rebut the all-out attack on her work and person.' He attributed the modest success of 'Since Silent Spring' to readers who were 'reluctant to let Carson go' and who had 'remained eager to see how her work and reputation had survived the assaults of the exploiters.' Frank Graham Jr. was born March 31, 1925, in Manhattan to Lillian (Whipp) Graham and Frank Sr., a prominent sports reporter and columnist for The New York Sun and The New York Journal-American. Frank Jr. grew up mostly in suburban New Rochelle, N.Y., where his interest in nature was sparked. Advertisement During World War II, he served in the Navy aboard the escort aircraft carrier Marcus Island as a torpedoman's mate. He saw action throughout the Pacific, fighting in the Battle of Okinawa in April 1945. After being discharged, he studied English at Columbia University and graduated with a bachelor's degree in 1950; he had worked as a copy boy at The Sun during the summers. With help from his father, Mr. Graham was hired by the Brooklyn Dodgers and promoted in 1951 to publicity director. He left the job in 1955, after the Dodgers beat the Yankees for the first time in the World Series. Mr. Graham went on to become an editor and writer at Sport magazine, where he stayed for three years, and then worked as a freelance writer for various publications, including The Saturday Evening Post, The Atlantic Monthly, Sports Illustrated, and Reader's Digest. He was also the author of 'Casey Stengel: His Half Century in Baseball' (1958), a biography of the Yankees' idiosyncratic and immensely successful manager; collaborated with Mel Allen, one of the Yankees' star broadcasters, on 'It Takes Heart' (1959), a book about heroic athletes; and wrote 'Margaret Chase Smith: Woman of Courage' (1964), about the trailblazing independent Republican US senator from Maine. In 1981, Mr. Graham wrote 'A Farewell to Heroes,' which he called a 'dual autobiography' of his father and himself. The cover photograph shows Mr. Graham as a child at Yankee Stadium -- dressed in a jacket, tie, overcoat and Lou Gehrig's Yankees cap -- standing in a dugout beside Gehrig, the Yankees' slugging first baseman, who was a friend of Frank Sr.'s and a neighbor in New Rochelle. Advertisement Mr. Graham married Ada Cogan in 1953. An author herself under the name Ada Graham, she and her husband wrote several children's books together about the natural world. She is his only immediate survivor. In 2013, Mr. Graham wrote in Audubon about the epiphany he once experienced in Central Park in New York when, using powerful new binoculars, he saw a black-and-white warbler. It was a warbler 'as I had never seen one: resplendent in its fresh nuptial plumage, every detail clear and sharp,' he wrote. 'It was a revelation. The memory of that long-ago bird has never left me; it amplifies my pleasure every time I see one of its descendants.' This article originally appeared in
Yahoo
09-06-2025
- Health
- Yahoo
US regulators move forward on controversial policy change that could pose risks to human health: 'By then it'll be too late'
The United States Environmental Protection Agency is considering the approval of a new pesticide ingredient that contains per- and polyfluoroalkyl substances, or PFAS, a class of harmful chemicals. The potential approval has sparked concerns among health and environmental advocates. As The New Lede reported in early May, the EPA announced the proposed registration of cyclobutrifluram, a chemical designed to control pests and diseases in crops such as soybeans, lettuce, cotton, and ornamental plants, per an April EPA news release. Developed by Syngenta, the chemical is being marketed as the active ingredient in the agritech company's new product Tymirium, which is intended to protect plants from parasitic nematodes and fungal diseases. "It will give farmers the freedom to maximize their yields without having to compromise on sustainability," Jon Parr, then-president of global crop protection at Syngenta, said in a 2020 statement. However, environmental groups have urged the EPA to reject the registration of cyclobutrifluram, citing concerns about potential long-term health and ecological impacts since the chemical falls into the PFAS category. This group of chemicals is known to accumulate in human bodies and the environment for decades, possibly centuries. While the EPA says it didn't find any risks to human health or threats to animals when the chemical was used in line with directions, the agency opened a portal for public comments and will consult with the U.S. Fish and Wildlife Service before making a final decision. The New Lede reported that opponents of the chemical are concerned its registration will be approved anyway. "We're quickly returning to the age of the 1960s and 1970s, when really persistent pesticides, like DDT, were in wide use," Nathan Donley, the Center for Biological Diversity's environmental health science director, told the outlet. "The legacy of impacts of what the EPA's currently approving won't be known for decades. By then it'll be too late." PFAS have been called "forever chemicals" because natural processes do not easily break them down. They can persist in the environment long after contamination and in human bodies long after exposure. The chemicals have been linked to a slew of health problems, including increased cholesterol, reproductive issues, an increased risk of cancers, and developmental delays. In ecosystems, they can pose similar risks to wildlife and can harm habitats by contaminating air, water, soil, and food sources. Do you worry about having toxic forever chemicals in your home? Majorly Sometimes Not really I don't know enough about them Click your choice to see results and speak your mind. While the EPA designated two widely used PFAS — PFOA and PFOS — as hazardous substances in 2024 and banned 12 PFAS chemicals from nonfood pesticide products in 2022, the agency appears to support approval of this new PFAS-containing pesticide ingredient, according to an April memorandum. Given that PFAS compounds have been detected on around 4,000 farms across the U.S., and many fertilizers used to grow our food contain these chemicals, approving a pesticide that includes them could further contaminate food supplies. Environmental groups such as Toxic Free North Carolina and the Environmental Protection Network submitted petitions to the EPA expressing opposition to the registration of cyclobutrifluram. In its public comment, science, regulatory, and advocacy manager Sara Grantham wrote on behalf of the organization Beyond Pesticides, "PFAS should be banned from all products, and no new chemicals should be approved for use that fall into this class." While the period for public comment appears to have closed, residents may still consider sharing their opinions on the matter with elected officials and voicing support for pro-environment policies that protect human health and fragile habitats. In the meantime, lawmakers in Maryland are considering a sweeping ban on over 1,000 pesticides that contain forever chemicals, and environmental groups in the United Kingdom are urging the government to ban PFAS-containing pesticides after a study found the substances on numerous fruits and vegetables. Those who wish to mitigate their exposure to PFAS and pesticides now might consider buying organic produce or even growing their own fruits and vegetables, which may come with the added benefits of higher nutrient levels and lower grocery costs. Avoiding certain consumer goods, such as nonstick cookware, can also help reduce household PFAS exposures. Join our free newsletter for good news and useful tips, and don't miss this cool list of easy ways to help yourself while helping the planet.
Yahoo
08-06-2025
- Health
- Yahoo
Bed Bugs May Have Been The First Urban Pest to Ever Plague Humans
Humans were letting the bed bugs bite long before beds existed, and while they do live on other species, we're the main reason this notorious parasite is still going strong. In fact, bed bugs might have been the first pest to plague our cities – earlier than the black rat, for instance, which joined us in urban life about 15,000 years ago, and even the German cockroach, which only got the memo about 2,100 years ago. Researchers think the blood-sucking pests – Cimex lectularius – first jumped from their bat hosts onto a passing human some 50,000 years ago, a move which would change the course of the insect species forever. Human bed bugs, it turns out, have boomed since the Last Glacial Maximum about 20,000 years ago. But it's a different story for those populations that continued living on bats. "Initially with both populations, we saw a general decline that is consistent with the Last Glacial Maximum; the bat-associated lineage never bounced back, and it is still decreasing in size," says entomologist Lindsay Miles, from Virginia Tech. "The really exciting part is that the human-associated lineage did recover and their effective population increased." The researchers were able to track this evolution because the human bed bugs have a much narrower genetic diversity, since only a few 'founders' probably came with us when we abandoned life in caves. But our move into cities around 12,000 years ago is what really kicked off the human bed bug boom. This was only briefly interrupted when DDT was invented in the 1940s. Populations crashed, humans slept sweetly, and then five years later, the bed bugs were back. Since then, bed bugs have travelled around the world with us, and even become resistant to our pesticides. For now, it seems, bed bugs are here to stay. It's been a long-term relationship, after all. The research is published in Biology Letters. Your Brain Wrinkles Are Way More Important Than We Ever Realized Something Strange Happens to Your Eyes When You're Sexually Aroused 2-Year-Old Prodigy Joins 'High IQ' Club Mensa as Youngest Member Ever
