The outbreak of a new type of bird flu in China poses a “serious threat” to human health, but it is still too soon to predict how far it will spread, experts have said.
Of the 126 people known to be infected so far, 24 have died, with many more still severely ill in hospital.
The H7N9 virus has not, however, yet proved able to spread between people - which limits its global threat.
The threat should be “treated calmly, but seriously”, researchers advised.
There is concern over both the pace and severity of the outbreak.
There has been a relatively high number of known infections since the first case was detected in April.
Prof John McCauley, the director of a World Health Organization (WHO) collaborating centre in the UK, said: “It is unusual to get these numbers.”
How the virus spreads is key. As long as it can spread only from a bird to a person through direct contact it posses a relatively small risk globally - particularly in richer countries where such contact is rare. If it can spread from one person to another then the threat becomes much more potent. This has not yet happened and it is impossible to tell whether it will happen tomorrow or never.
Of those infected, a fifth died, a fifth recovered and the rest are still ill. The infection results in severe pneumonia and even blood poisoning and organ failure.
“The WHO considers this a serious threat,” said Prof McCauley, “but we don’t know at this stage whether this is going to spread from human to human.”
The emerald ash borer has killed 100 million ash trees since arriving in North America over 10 years ago. Now, mortality rates for people living in affected communities are increasing as well:
The blight was first detected in June 2002, when the trees in Canton, Michigan, got sick. The culprit, the emerald ash borer, had arrived from overseas, and it rapidly spread — a literal bug — across state and national lines to Ohio, Minnesota, Ontario. It popped up in more distant, seemingly random locations as infested trees were unwittingly shipped beyond the Midwest.
Within four years of first becoming infested, the ash trees die — over 100 million since the plague began. In some cases, their death has an immediate impact, as they fall on cars, houses, and people. In the long term, their disappearance means parks and neighborhoods, once tree-lined, are now bare.
Something else, less readily apparent, may have happened as well. When the U.S. Forest Service looked at mortality rates in counties affected by the emerald ash borer, they found increased mortality rates. Specifically, more people were dying of cardiovascular and lower respiratory tract illness — the first and third most common causes of death in the U.S. As the infestation took over in each of these places, the connection to poor health strengthened.
In a literal sense, of course, the absence of trees would mean the near absence of oxygen — on the most basic level, we cannot survive without them. We know, too, that trees act as a natural filter, cleaning the air from pollutants, with measurable effects in urban areas. The Forest Service put a 3.8 billion dollar value on the air pollution annually removed by urban trees. In Washington D.C., trees remove nitrogen dioxide to an extent equivalent to taking 274,000 cars off the traffic-packed beltway, saving an estimated $51 million in annual pollution-related health care costs.
How Not to Label Biotech Foods: Should Foods Made From Genetically Modified Plants or Animals Be Specially Labeled?
When Californians go to the polls this November, one of the ballot initiatives they will vote on will be the California Right to Know Genetically Engineered Food Act, a proposed law that would require that foods containing genetically modified organisms (GMOs) be specially labeled. This move for mandatory labeling is just the latest development in the ongoing controversy over the safety of genetically modified (GM) foods.
Proponents of the technology argue that creating GM plants and animals for human consumption is essentially no different from the selective breeding that farmers have carried out for millennia, which resulted in accumulated genetic changes over time. But the methods used to create today’s genetically modified organisms allow for more rapid and dramatic changes. Modern GMOs are often created using recombinant DNA techniques in which an organism’s genes are directly altered, often by inserting DNA fragments from other organisms. This approach offers much greater precision than selective breeding, removing the requirement of several generations of breeding for a particular trait to become widespread in a population. It also allows for the direct addition to an organism of novel traits that do not occur naturally in the species.
Critics cite concerns like the potential for loss of biodiversity, and fear that the widespread use of recombinant DNA techniques in agriculture represents a vast and as yet unproven experiment with uncertain consequences for human health and the environment. There are a few known cases of unintended negative consequences resulting from the use of GMOs: for example, the use of crops genetically engineered to be resistant to the powerful herbicide Roundup may have accelerated the emergence of weeds that are also resistant, and are spreading in the wild, in some cases creating a sort of war of attrition in which farmers must use additional herbicides or revert to manually removing the weeds. Although there is no evidence that these or any other GMOs have had adverse impacts on human health or safety — and indeed, the National Academies have repeatedly concluded that GM techniques pose no known unique risks to human health as compared to more traditional plant-breeding methods — some critics contend that GM foods should be considered unsafe for human consumption until proven otherwise, and others fear the possibilities of genetically modified organisms being released into the wild and damaging ecosystems, and believe they should not be permitted at all.
Mobile phone exposure limits and testing requirements should be reassessed, according to a Government Accountability Office study released Tuesday.
The study, the culmination of a year-long review done at the urging of lawmakers, comes at a time of heightened concern about the possible impact of cellphone radiation on human health. Its findings may prompt the Federal Communications Commission to update its standards to more accurately reflect how people use their cellphones.
While the report did not suggest that cellphone use causes cancer, the agency did say that FCC’s current energy exposure limit for mobile phones, established in 1996, “may not reflect the latest evidence on the the effects” of cellphones. The study recommends that the FCC reassess two things: the current exposure limit and the way it tests exposure.
In its conclusions, the report says that the FCC has not formally coordinated with the Food and Drug Administration or the Environmental Protection Agency on the exposure limits. The report also raised questions about the FCC’s decision to only test exposure at a distance from a body while using an earpiece, simulating, for example, someone setting their phone on a nearby table rather than in their pocket while speaking.
The FCC, the report said, “may not be identifying the maximum exposure, since some users may hold a mobile phone directly against the body while in use.”
Trees, bushes and other greenery growing in the concrete-and-glass canyons of cities can reduce levels of two of the most worrisome air pollutants by eight times more than previously believed, a new study has found. A report on the research appears in the ACS journal Environmental Science & Technology.
Thomas Pugh and colleagues explain that concentrations of nitrogen dioxide (NO2) and microscopic particulate matter (PM) — both of which can be harmful to human health — exceed safe levels on the streets of many cities. Past research suggested that trees and other green plants can improve urban air quality by removing those pollutants from the air. However, the improvement seemed to be small, a reduction of less than 5 percent. The new study sought a better understanding of the effects of green plants in the sometimes stagnant air of city streets, which the authors term “urban street canyons.”
The study concluded that judicious placement of grass, climbing ivy and other plants in urban canyons can reduce the concentration at street level of NO2 by as much as 40 percent and PM by 60 percent, much more than previously believed. The authors even suggest building plant-covered “green billboards” in these urban canyons to increase the amount of foliage. Trees were also shown to be effective, but only if care is taken to avoid trapping pollutants beneath their crowns.
The Cigarette Smokescreen: The FDA is passing up a historic opportunity to reduce the harmful effects of tobacco
Cigarette smoking is one of the major preventable scourges of human health. Public health experts and regulators—and yes, even smokers—know it. But by being politically correct and focusing on unproven or misguided approaches, the FDA is passing up a historic opportunity to mitigate the health effects of cigarette smoking. Specifically, FDA officials are struggling to reconcile science and politics in applying their new powers to regulate tobacco. They aren’t succeeding.
As a result of the landmark 2009 Family Smoking Prevention and Tobacco Control Act, the FDA was tasked with regulating not just cigarettes, but a range of tobacco products. The agency’s oversight of tobacco is fundamentally different from any other product it regulates simply because tobacco is an inherently, irredeemably dangerous product. Unlike drugs, it isn’t beneficial in any way; and unlike food, it isn’t a necessity.
The legislation gives the FDA the authority to review and ban proposed new products unless they are proven to significantly improve public health. This has already led to unanticipated legal and scientific arguments over so-called “reduced harm” products.
The director of the FDA’s Center for Tobacco Products, Dr. Lawrence Deyton, seemed to be on the right track, at least in principle, when he told the Society for Research on Nicotine and Tobacco last year that “complex problems require multi-faceted, comprehensive approaches based on the best available science.”
However, the agency’s approach to several regulatory issues belies Deyton’s homage to science (a traditional trapping of many a regulator assuming a new office).
All tobacco products are not created equal. Cigarettes are by far the deadliest of them all, but other forms of tobacco, particularly smokeless products such as Swedish-style snus or newer dissolvable products, although not entirely safe, are far less harmful. Studies in Sweden have shown that such products can be used by smokers to reduce their tobacco-related risk.
It may seem counter-intuitive but nicotine, although highly addictive, is not particularly bad for you in the amounts delivered by cigarettes or smokeless products. The vast majority of the health risks from tobacco come from the burning and inhalation of smoke. Quitting tobacco altogether remains the ideal outcome, but switching to lower-risk products would be a boon to the health of smokers. This sort of “harm reduction” via substitution of a lesser evil is philosophically similar to the administration of methadone to wean addicts off heroin and to the rationale for treating cancer with highly toxic chemotherapeutic drugs.
Tobacco is an inherently, irredeemably dangerous product.
Yet smoking tobacco is so reviled among public health activists that many are reluctant to acknowledge that some tobacco products are far less dangerous than others, and that harm reduction is a valid, if imperfect, solution.
Will the FDA endorse tobacco harm reduction and thereby help smokers who have failed to quit by traditional means—and whose success rates are poor—or will it buy into the “quit or die” approach endorsed by many tobacco control activists?
While the jury is still out, some of the questions posed by the FDA at a workshop last year suggested a sweeping anti-tobacco, rather than anti-smoking, approach. The scientists, appointed by the FDA, focused on whether the introduction of modified-risk tobacco products, and the reduced-risk claims manufacturers would like to make for them, would reduce overall tobacco use. But that is the wrong question. Instead, they ought to be asking how they can set up a regulatory environment that would lead to fewer and less severe tobacco-related diseases. The distinction is critical, underscoring the difference between an anti-tobacco agenda and a policy that embraces life-saving harm reduction.
A previous example of the FDA’s resistance to harm reduction came in July 2009, when the agency issued a warning about a product called e-cigarettes, which many smokers were (and are) using to give up real cigarettes. They look like cigarettes and many versions supply users with vaporized nicotine, some even boasting an LED light at the tip for verisimilitude. They contain no tobacco and are non-combustible, and thus do not expose users to the risks of smoking. For the vast majority of smokers unable to quit even with the help of drugs and counseling, e-cigarettes could be a life-saver; but after performing a cursory laboratory analysis of the products, regulators warned smokers to avoid them, essentially telling them to stay with deadly cigarettes.
Billions of engineered nanoparticles in foods and pharmaceuticals are ingested by humans daily, and new Cornell research warns they may be more harmful to health than previously thought.
A research collaboration led by Michael Shuler, the Samuel B. Eckert Professor of Chemical Engineering and the James and Marsha McCormick Chair of Biomedical Engineering, studied how large doses of polystyrene nanoparticles — a common, FDA-approved material found in substances from food additives to vitamins — affected how well chickens absorbed iron, an essential nutrient, into their cells.
The results were reported online Feb. 12 in the journal Nature Nanotechnology.
According to the study, high-intensity, short-term exposure to the particles initially blocked iron absorption, whereas longer-term exposure caused intestinal cell structures to change, allowing for a compensating uptick in iron absorption.
The researchers tested both acute and chronic nanoparticle exposure using human gut cells in petri dishes as well as live chickens and reported matching results. They chose chickens because these animals absorb iron into their bodies similarly to humans, and they are also similarly sensitive to micronutrient deficiencies, explained Gretchen Mahler, Ph.D. ‘08, the paper’s first author and former Cornell graduate student and postdoctoral associate.
The researchers used commercially available, 50-nanometer polystyrene carboxylated particles that are generally considered safe for human consumption. They found that following acute exposure, a few minutes to a few hours after consumption, both the absorption of iron in the in vitro cells and the chickens decreased.
But following exposure of 2 milligrams per kilogram for two weeks — a slower, more chronic intake — the structure of the intestinal villi began to change and increase in surface area. This was an effective physiological remodeling that led to increased iron absorption.
“This was a physiological response that was unexpected,” Mahler said.
Shuler noted that in some sense this intestinal villi remodeling was positive because it shows the body adapts to challenges. But it serves to underscore how such particles, which have been widely studied and considered safe, cause barely detectable changes that could lead to, for example, over-absorption of other, harmful compounds.
Human exposure to nanoparticles is only increasing, Shuler continued.
“Nanoparticles are entering our environment in many different ways,” Shuler said. “We have some assurance that at a gross level they are not harmful, but there may be more subtle effects that we need to worry about.”
The paper included Cornell co-authors Mandy Esch, a research associate in biomedical engineering; Elad Tako, a research associate at the Robert W. Holley Center for Agriculture and Health; Teresa Southard, assistant professor of biomedical sciences; Shivaun Archer, senior lecturer in biomedical engineering; and Raymond Glahn, senior scientist with the USDA Agricultural Research Service and courtesy associate professor in the Department of Food Science. The work was supported by the National Science Foundation; New York State Office of Science, Technology and Academic Research; Army Corp of Engineers; and U.S. Department of Agriculture.