Chamber of wisdom
Trying to understand infectious diseases is what engineer Clive Beggs has built his career around—quite literally. The medical technology professor at the University of Bradford in England has helped build one of only a few chambers in the world that can precisely study the hospital environments in which microbes tend to infect people.
"If you look at a common laboratory, you'll find microbes in Petri dishes or in a broth, but that tells you little about how they really behave in realistic environments," Beggs said.
The 2,825-cubic-foot (80-cubic-meter) climate-controlled room goes online in November and contains a mock-up of a hospital ward. The research team made of doctors, engineers, mathematicians and other specialists hopes to study how microbes "get from A to B and what they do in between," Beggs said.
"We want to see how nurses tear down patients' beds, for example, and find out how that might help spread microbes like C. diff," Beggs said, referring to Clostridium difficile—a drug-resistant microbe that is currently ravaging hospitals in Europe.
"It's difficult to do the research we'd like to do in a real hospital," he said. "There are bureaucratic issues in gaining access to hospitals, and there's a huge amount of variables we can't control." In addition, Beggs said follow-up clinical studies are long and expensive—so having the most accurate and reliable information possible before taking the plunge is crucial.
Before the researchers investigate how best to clean hospital rooms, however, they will first focus on how humidity affects superbugs. "A few studies suggest the drying effects of (air conditioning) could control the spread of some microbes," Beggs said. "But overall, there's little research in this area. We want to change that and possibly help people."
Beggs said such environmental countermeasures to prevent bacteria's spread are extremely important, especially if there are fewer new antibiotics in the pipeline. "In general, hospitals are doing everything they can to maintain clean and safe facilities, but we don't fully understand how ward environments affect the spread and development of superbugs," he said.
Stopping a superbug
While research groups such as Beggs' come up with new ways to thwart dangerous microbes and others seek new antibiotics, some experts think vaccines are as important as ever. Problem is, the disease-preventint injections are as financially unattractive as new antibiotics.
"Nobody will invest in a vaccine to fight a disease that isn't very widespread," said Donald Kennedy, a medical professor at St. Louis University's School of Medicine. If vaccine development could get a boost, however, Kennedy thinks microbes like MRSA could get the boot, much like smallpox, or at least be set back as measles, polio and hepatitis B are in the United States.
"Vaccination strategies have eliminated or reduced those diseases, not treatment strategies," he said. "It's a challenge, but if we're smart enough we could do it. Most people would rather not catch a disease than take drugs while they have one."
Until more advanced solutions come along, people are sticking to tried-and-true advice any doctor would offer: Wash your hands, and wash them often.
"That's what our school is recommending our students do," said Tricia Gordon, a public high school teacher in Manassas, Va., where MRSA outbreaks have occurred. "We've sent out public health warnings and information. We're also now requiring kids who play sports to get cleared if they have any sores and we've updated our cleaning supplies to handle (MRSA)."
Gordon said most people use the information responsibly, but some seem to be acting a little paranoid.
"Some people think the situation is a bit extreme, with kids thinking they have it when with every little pimple that shows up," she said. "Knowledge is power, but you have to keep your head screwed on and act on common sense."
To do that, Hopkins said following up on public health warnings is crucial.
"Don't react to the 11 o'clock news and get scared. Go to your health department's Web site for detailed information," Hopkins said. "And don't forget to wash your hands."
Study Ties Time Shift, Pedestrian Deaths
Their study of risk to pedestrians is preliminary but confirms previous findings of higher deaths after clocks are set back in fall.
It's not the darkness itself, but the adjustment to earlier nighttime that's the killer, said professors Paul Fischbeck and David Gerard, both of Carnegie Mellon University in Pittsburgh.
Fischbeck, who regularly walks with his 4-year-old twins around 6 p.m., is worried enough that he'll be more cautious starting Monday.
"A three times increase in the risk is really dramatic, and because of that we're carrying a flashlight,'' he said.
Fischbeck and Gerard conducted a preliminary study of seven years of federal traffic fatalities and calculated risk per mile walked for pedestrians. They found that per-mile risk jumps 186 percent from October to November, but then drops 21 percent in December.
They said the drop-off by December indicates the risk is caused by the trouble both drivers and pedestrians have adjusting when darkness suddenly comes an hour earlier.
The reverse happens in the morning when clocks are set back and daylight comes earlier. Pedestrian risk plummets, but there are fewer walkers then, too. The 13 lives saved at 6 a.m. don't offset the 37 lost at 6 p.m., the researchers found.
The risk for pedestrian deaths at 6 p.m. is by far the highest in November than any other month, the scientists said. The danger declines each month through May.
The Insurance Institute for Highway Safety of Arlington, Va., in earlier studies found the switch from daylight saving time to standard time increased pedestrian deaths. Going to a year-round daylight saving time would save about 200 deaths a year, the institute calculated, said spokesman Russ Rader.
"Benjamin Franklin conceived of daylight savings time as a way of saving candles,'' Rader said Friday. "Today we know it saves lives.''
The risk at 6 p.m. in November, after daylight saving time ends, is 11 times higher than the risk for the same hour in April, when daylight saving begins, according to the Carnegie Mellon researchers.
Fischbeck and Gerard used federal traffic fatality data that they've incorporated into a searchable database for different risk factors. Their analysis was not peer-reviewed or being published in a scientific journal.
But it does jibe with other peer-reviewed studies that looked at raw fatalities.
A 2001 study by John M. Sullivan at the University of Michigan looked at national traffic statistics from 1987 to 1997 and found that there were 65 crashes killing pedestrians in the week before the clocks fell back and 227 in the week after.
Fischbeck and Gerard found the increase in fatality risk after the end of daylight saving time is only for pedestrians. No such jump was seen for drivers or passengers in cars.
Once everyone "springs forward'' to daylight saving time in April, there is a 78 percent drop in risk at 6 p.m., they said.
But overall for the evening rush hour, turning the clock back is a killer. In seven years there have been 250 more deaths in the fall and 139 fewer deaths in the spring.
"This clearly shows that both drivers and pedestrians should think about this daylight savings adjustment,'' Gerard said. "There are lives at stake.''
Strange but True: Snake Oil Salesmen Were on to Something
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SNAKE OIL: Chinese water snakes have lots of omega 3 fatty acids in their oil, meaning such snake oil might actually cure aches and pains. |
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Throughout the 19th century salesmen traveled the U.S. peddling solutions to all medical ills. As depicted in numerous Westerns and in Mark Twain's Huckleberry Finn, the "doctor" was aided by a shill in the crowd who would, at the appropriate moment, call out that this medicament, ointment or tincture had solved his woes. Once the unsuspecting public had purchased the con artists' wares, both would quickly depart before the townspeople discovered the worthlessness of the claims.
One of the most common cure-alls was snake oil, and its less than sterling efficacy soon lent its name as a generic to all such fraudulent hoaxes. The epithet endures: A quick search for "snake oil" on the Internet reveals that it still refers almost exclusively to something worthless and fake. But some of those original itinerant salesmen may have peddled actual Chinese snake oil, and those who did may not have been fraudulent after all.
For centuries snake oil has been a folk remedy in Chinese medicine, used primarily to treat joint pain such as arthritis and bursitis. Its introduction to the U.S. most likely occurred with the arrival of Chinese laborers who came to build the Transcontinental Railroad in the mid 1800s. They may have offered snake oil to fellow workers as relief for suffering long days of physical toil.
Richard Kunin, a California psychiatrist with a background in neurophysiology research, became intrigued with the idea of snake oil in the 1980s. He had been following early research on the importance of omega-3 fatty acids for health and it dawned on him that the much maligned snake oil might be a particularly rich source. Omega-3's proliferate in cold-blooded creatures that live primarily in cooler environments because the fats don't harden in chilly water like omega-6 fatty acids do (hence, the high level of omega-3's in cold-water fish such as salmon). "Snakes and fish share one thing, they're both cold-blooded animals," Kunin says.
Kunin visited San Francisco's Chinatown to buy such snake oil and analyze it. He also acquired two live rattlesnakes and extracted their fat sacks. According to his 1989 analysis published in the Western Journal of Medicine, Chinese water-snake oil contains 20 percent eicosapentaenoic acid (EPA), one of the two types of omega-3 fatty acids most readily used by our bodies. In comparison, the rattlesnakes had only 8.5 percent EPA. And salmon, one of the most popular food sources of omega-3's, contains a maximum of 18 percent EPA, lower than that of snake oil.
Research since the 1980s has demonstrated the necessity—and efficacy—of omega-3 fatty acids. These acids not only reduce inflammation, such as arthritis pain, but also improve cognitive function and reduce blood pressure, cholesterol and even depression. "Because of their chemical structure, omega-3's behave very differently in cell membranes than any other fat," says Susan Allport, author of The Queen of Fats: Why Omega-3s Were Removed from the Western Diet and What We Can Do To Replace Them. "They're much more dynamic, they move around much more, so they allow a lot to happen in the cell membranes. And that's where enzymes do their work. So these fats allow enzymes to work."
Recently in Japan, a group of scientists at the Japanese National Food Research Institute led by Nobuya Shirai turned their attention to snake oil as well. In 2002, in Fisheries Science, they evaluated the composition of oil from the Erabu sea snake—the source of snake oil in traditional Chinese medicine. They analyzed such snakes caught in both the Pacific Ocean and the South China Sea and determined that the amount of beneficial omega-3s in sea snakes does not vary depending on their capture location.
In a series of later papers, the most recent published in the Annals of Nutrition & Metabolism in July 2007, Shirai and his team evaluated the effects of Erabu sea-snake oil on a number of outcomes in mice, including maze-learning ability and swimming endurance. In both cases, snake oil significantly improved the ability of the mice in comparison with those fed lard.
Despite Shirai and Kunin's analyses, snake oil retains its fraudulent feel in the U.S., perhaps because the Japanese research is not widely known and we were only beginning to understand the need for omega-3's when Kunin published his analysis. "That study came out at the time that we were beginning to appreciate that we did indeed require omega-3's," Allport says. "The first medical reason people were looking at omega-3's was for arthritis…. [But] all of our cells in our bodies have a certain amount of omega-3's in them. Now we concentrate [research] on the brain and the heart because those are organs that have a higher concentration. But all our cells need these fats in them."
Of course, most 19th-century snake oil salesmen did not, in fact, sell this particular product. Even those hucksters who did sell actual snake oil would likely have sold the rattlesnake variety, nearly useless for any ache-relieving medicinal purpose. But the original Chinese purveyors of snake oil offered something that probably did exactly what they claimed it would do: help fellow workers relieve the pain of their labors.
Kill the Virus, Stop the Cancer
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CANCER TARGETS?: Key to treating some cancers may be blasting viruses that cause them before they morph into malignancies. |
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Researchers have for the first time shown that as many as 1.3 million cases of cancer a year may one day be successfully treated or even prevented by targeting and destroying the viruses that cause them.
Scientists at the Albert Einstein College of Medicine of Yeshiva University in New York City say the finding could pave the way for conquering human cancers that are linked to preexisting viral infections, among them liver cancer (caused by the hepatitis B and C viruses), cervical cancer (from human papillomavirus) and lymphomas caused by the Epstein–Barr virus.
They key, they say, is to find and destroy the viruses before they turn cancerous. In an attempt to do this, the researchers used a technique known as radioimmunotherapy in which radioisotopes (unstable elements that release radiation) mounted on antibodies (protein molecules akin to infection search-and-destroy missiles) are injected into the body. Once inside, researchers found that the antibodies zeroed in on their targets—viral antigens—and the radioisotopes destroyed nearby cancer cells without damaging surrounding healthy tissue.
Viral antigens are proteins produced by virus-infected cells that can cause those cells to go berserk and start multiplying out of control, thereby becoming cancerous. Antibodies are immune proteins with binding sites that can fit like puzzle pieces into corresponding sites on foreign viral or bacterial antigens and disable them (triggering other immune responses). The problem with viruses that typically cause cancer, though, is that they tend hide out of reach—inside of rather than on the surface of cells. The Einstein researchers, however, found a way around that.
"We had a hunch that rapidly growing tumors can 'outgrow' their blood supply, resulting in dead tumor cells that might spill their viral antigens amongst the living cancer cells," said co-senior study author Arturo Casadevall, chair of Einstein's Microbiology & Immunology department. "So we hoped that by injecting antibodies hitched to isotopes into the blood that they'd be carried deep into the tumor mass and would latch onto these now-exposed antigens. Then the blast of radiation emitted by the radioisotope would destroy the…tumor cells nearby."
The researchers tested their theory on mice, attaching the radioisotope rhenium 18 to antibodies that attack E6, a viral antigen produced by virtually all cervical cancer cells. They prepared a similar weapon against liver cancer by piggybacking rhenium 18 on antibodies that target HBx, a viral antigen made by cancerous liver cells. The mice, which had been injected with human cervical and liver cells, were treated with the appropriate radioimmunotherapy.
In both cases, researchers report in PLoS ONE the therapies significantly slowed tumor growth compared with results in untreated mice. In the animals with cervical cancer, the tumors not only stopped growing but some actually shrunk.
"Radioimmunotherapy not only worked against these cancers but, in addition, the radioactivity was confined entirely to the tumor masses, leaving healthy tissues undamaged," said senior study co-author Ekaterina Dadachova, an associate professor of nuclear medicine and of microbiology and immunology at Einstein.
Dadachova, a pioneer in the use of radioimmunotherapy against infectious diseases, previously successfully turned it on a streptococcal bacterium that causes pneumonia. Last year, she and her colleagues showed that the therapy could also be used to help halt HIV by targeting one of several viral proteins on the surface of HIV-infected cells.
"Our study has shown in principle that radioimmunotherapy can help in treating cancers caused by viruses—and, just as exciting, the approach also holds promise for cancer prevention,'' she said. "In people chronically infected with hepatitis B or C, human papillomaviruses or other viruses known to cause cancer, radioimmunotherapy could potentially eliminate virus-infected cells before they're able to transform into cancer cells."
The Truth About Deadly 'Superbugs'
It sounds more like a sci-fi movie plot than reality, but "superbugs"—deadly microbes that can resist drugs designed to wipe them out—are far from imaginary. Schoolchildren in several states recently have died from infections caused by MRSA bacteria, otherwise known as methicillin-resistant Staphylococcus aureus, and medical recordkeeping shows such cases are increasing annually.
MSRA spreads via surface-to-surface contact, developing into a staph infection if conditions are right. The first symptoms can include pimple-like sores on the skin where the bacteria launch their attack, while rarer but more advanced infections can enter the bloodstream, attack organs and lead to death.
But need the masses live in fear of stubborn yet deadly microbes such as MRSA as their numbers rise worldwide, or are we overreacting?
Most medical experts think superbug diseases are here to stay but offer a major caveat: Only a fraction of the population need worry a little, if at all.
The numbers
An estimated 18,650 Americans died in 2005 from MRSA, a microbe whose defenses have benefited from decades of assault by antibiotics.
"The spread of MRSA isn't a flash in the pan. It's been around for about 50 years now," said Dr. Cyrus Hopkins, an infectious diseases specialist at Massachusetts General Hospital. Healthy people are hardly its favorite customers and rarely meet the microbe.
About 77 percent of deaths from MRSA in 2005 occurred in people 65 or older, according to a recent study in the Journal of the American Medical Association, an age bracket known for weakened immune systems. For people younger than 65, the chances of dying from a lightning strike (about 1 in 600,000) are greater.
"I think people should understand that the chance of being exposed to a superbug is very small," Hopkins said. "Even if they are exposed, the chance they'll get sick from it is very small. And if they do get sick, most healthy people survive."
The chances are low, Hopkins explained, because the body's immune system can fight dangerous invasions; in addition, populations of "friendly" microbes living inside of our bodies easily out-compete invaders. Twenty-five to 30 percent of people, in fact, carry harmless S. aureus bacteria inside their nose as "natural flora."
The principle of natural flora explains how most Escherichia coli strains live peacefully within our intestines. Eat some spoiled or improperly cooked food, however, and a bigger dose of those or other more foreign bacteria can lead to diarrhea or infection if the microbial visitors to your gut are virulent, as were E. coli strains contaminating spinach earlier this year.
Evolution on drugs
But where do the harmful, drug-resistant nemeses come from? Experts think the answer lies in how we combat diseases with antibiotics.
Antibiotics shut down unruly bacteria directly, police them until the immune system can rid of them or both. And each new antibiotic on the market works well—at least for a few years, said Dr. Martin Blaser, a professor at New York University's School of Medicine and former president of the Infectious Diseases Society of America (IDSA).
Medical experts such as Blaser think the forces of evolution start working as soon as patients carrying a dangerous microbe receive antibiotics.
"Anyone who doesn't believe in evolution just has to look at MRSA," Blaser said of the microbe's growing arsenal of drug resistance.
Kill off millions or billions of harmful bacteria with an antibiotic, and some stragglers with a life-saving genetic change carry on their heritage. If a similar drug is used again, it's much less effective than before; repeat the cycle, and eventually microbes like MRSA make news headlines.
Making matters worse, Blaser said, is that drug companies have little incentive to create new antibiotics—they are expensive to test, and the customer turnaround is quick and unprofitable.
"Until we develop new antibiotics and change our usage—we use antibiotics like water—these problems will persist," said Blaser, who is lobbying congress with other IDSA members to offer monetary incentives to develop new antibiotics.
But recent victims of virulent S. aureus strains that killed schoolchildren have many medical experts on edge, as most victims were healthy. Blaser said the responsible MSRA strains probably did not come out of hospitals, which are well-known breeding grounds for drug-resistant diseases.
"It's not just affecting previously ill people," Blaser said. "It's football players, wrestlers and just plain healthy kids."
Blaser thinks the microbial attackers somehow evolved to be more invasive than their more bashful in-laws.
Sustained attack
The growing world population may be the force whacking the evolutionary beehive for virulence, a measure of a microbe's ability to infect something.
People used to live in small, spread-out communities, so when super-aggressive diseases did appear, Blaser said they couldn't get very far.
"Every time a virulent disease popped up, it was 'end of story.' They had nowhere else to go," he said.
But today, populations are immense, tightly connected around the globe and contain growing elderly populations as well as carriers of immune-weakening diseases such as HIV. Blaser said the combination is a recipe for disaster, and his group's new model of that recipe was detailed the Oct. 18 issue of the journal Nature.
"We did not make the laws of nature," Blaser said. Even though we may not like them, we need to understand them to better control infectious diseases."
Hospitals and Superbugs: Go in Sick... Get Sicker
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CAN HOSPITALS MAKE YOU SICK?: Healthcare facilities are supposed to be places to go to get well, but who knew they could actually make you sicker? |
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Kat Gehrke, 25, had no idea that delivering her first baby would lead to the biggest nightmare of her life. On July 5, 2006, Gehrke had a cesarean section at Indian River Memorial Hospital in Vero Beach, Fla.—after more than 20 hours of labor her cervix had not dilated more than 1.6 inches (four centimeters). The procedure seemed to go off without a hitch, and her doctor sent her and new daughter Kaylie home after just two days in the hospital.
All seemed fine, except "my temperature never went back to normal after surgery," Gehrke says. During her first few days at home, she had a low-grade fever that hovered around 100 degrees Fahrenheit (38 degrees Celsius) and she noticed a lump had formed below her incision. By the fourth day, the lump had ballooned to the size of a lime, her fever had jumped to 103 degrees F and her incision was intensely painful. "It was like someone had taken a burning match and stuck it inside" the cut skin, Gehrke says. She immediately went to see her doctor, who took out the staples (as is customary a few days after a C-section) and examined the growing bulge under the wound. He dismissed the pain as normal and prescribed antibiotics for what he diagnosed as a breast infection based on a nickel-size lump that he felt in one breast. But he was wrong. "I didn't have a breast infection at all," Gehrke says, noting that the breast lump was merely a clogged milk duct (common in women who nurse).
A few days later, part of the incision burst open, releasing so much blood and fluid that "the entire [bathroom] floor was soaked in blood," Gehrke says. "My grandma took two beach towels to sop it all up."
Gehrke's grandfather rushed her to Indian River Memorial's emergency room where doctors and nurses cleaned the wound and packed it with gauze to allow for drainage. They sent a sample of the fluid to the hospital lab for analysis and called Gehrke's ob/gyn to inform him that the infection was probably caused by the bacterium Escherichia coli. Gehrke's ob/gyn prescribed sulfa antibiotics, which are commonly used to treat E. coli infections. Two days later, the lab results came back, revealing that Gehrke did not have E. coli, but rather a staphylococcus, or staph, infection caused by methicillin-resistant Staphylococcus aureus (MRSA), a potent bacterium that has developed resistance to most of the old standby antibiotics, making it difficult to treat and potentially fatal.
MRSA causes some 94,000 invasive infections in the U.S. each year, resulting in almost 19,000 deaths—more than those caused by human immunodeficiency virus (HIV)—said a study published this week in JAMA The Journal of the American Medical Association. And "the majority of these cases appeared to be health care–acquired," says Elizabeth Bancroft, a medical epidemiologist with the Los Angeles County Department of Public Health and author of an editorial that accompanied the study.
Learning the infection was MRSA, Gehrke's gynecologist immediately switched her to a stronger antibiotic and put her on bed rest; nurses from the Visiting Nurses Association came to her house daily to pack the wound in gauze and check her vital signs. But the swelling remained and the wound continued to ooze pus.
After three months of this, the wound still had not healed. At the advice of her ob/gyn's partner (who was filling in for her doctor that day), Gehrke went to see doctors at Indian River Hospital's wound care facility. They told her she needed a second operation to remove the tissue destroyed by the infection. Surgeons reopened her incision and discovered a festering infection that had caused extensive damage. It was "like looking at a hole in your belly [that is] seven inches wide and six-and-a-half inches deep," she recalled in an interview with ScientificAmerican.com. After the operation, Gehrke stopped seeing her ob/gyn, but continued to be treated by the wound care physicians and visiting nurses. She says she was mostly bedridden for another three months because it was painful to move while attached to a wound V.A.C., a suction device that aids healing by vacuuming pus, blood and other fluids.
Gehrke survived but it took seven months when all was said and done for the infection to clear up and the wound to heal. She says she was bedridden for a total of six months and racked up $13,000 in out-of-pocket expenses for home care and procedures associated with her infection.
"My credit is shot," says Gehrke, who works as a server at a local restaurant and whose husband works as a diesel mechanic for Wal-Mart. Their combined salaries amount to about $34,000 annually before taxes.
Gehrke asked her ob/gyn why this had happened. "'These things happen in hospitals' is pretty much what he told me," she says.
It is difficult to pinpoint the source of Gehrke's infection. It may have stemmed from a dirty instrument used during her C-section or from unwashed hands or the contaminated gloves of a health care worker. But one thing is almost certain: she picked up the bug at the hospital.
Gehrke is one of millions of patients who have unwittingly contracted infections in hospitals, where they went expecting to get well—but instead got sicker. Every year nearly 100,000 people die of infections they developed in U.S. hospitals and healthcare facilities, a greater number than those killed in homicides and car accidents combined. Some 1.7 million patients contract hospital infections annually, according to the most recent data from the Centers for Disease Control and Prevention (CDC).
Many of these infections are caused by multidrug-resistant superbugs such as MRSA and vancomycin-resistant enterococci (VRE). Heavy use of antibiotics in hospitals encourages the emergence of stronger and stronger bacteria. Exposing a bacterial strain to one antibiotic essentially weeds out the weak and selects the hearty bugs that can survive. Then the next generation of antibiotics is called on; eventually the bugs become resistant to that as well and the bacteria continue evolving until eventually no antibiotic can kill them. "You can end up with bugs that we really don't have medications to kill," says Allison Aiello, assistant professor of epidemiology at the University of Michigan School of Public Health. Experts estimate that more than 70 percent of all hospital-acquired infections are caused by bacteria that are resistant to at least one of the drugs commonly used to treat them.
Hospitals not only provide optimum conditions for the evolution of superbugs, but they also provide a plethora of inviting pathways for bacteria to get inside human bodies: open wounds from surgical incisions, catheter tubes running in and out of blood vessels and urinary tracts, and ventilators inserted through noses or throats and into windpipes.
What's most shocking about hospital infections, experts say, is that most of them can be avoided. "The vast majority of all hospital infections are preventable," Bancroft says. In the past, "the mantra was that hospital infections are inevitable," she says, but the attitude is changing because many hospitals have proved it wrong.
In 1978 the University of Virginia (U.V.A.) Medical Center in Charlottesville had its first case of MRSA. The bug spread from patient to patient despite the fact that health care workers were washing their hands after touching bodily fluids as well as donning gowns, gloves and masks when caring for patients with clear signs of MRSA infections (such as pus-discharging wounds or pneumonic coughing), says Barry Farr, who was a medical resident at the time and is now professor emeritus of U.V.A.'s Department of Medicine. By 1980, nearly half of the hospital's staph infections were caused by MRSA.
In an effort to control the problem, the hospital decided to actively seek out and isolate not only patients infected with MRSA but also those who were colonized, meaning they carried the bug on their skin or inside their noses, sputum or urine. (People who are colonized may be carrying millions, if not billions, of bacteria that can easily spread to others, either through direct contact or by touching common surfaces such as bed rails, doorknobs and blood pressure cuffs). U.V.A. began testing all high-risk patients for MRSA infection and colonization; those who tested positive were placed in contact-isolation areas with warning signs on their doors alerting health care workers of the patients' contagious status and instructing them to wash their hands after touching them. (The CDC did not even recommend hand washing before and after all patient contacts at this time.) Using active detection and isolation, U.V.A. had totally wiped out MRSA within 18 months, Farr says. "I watched this work at U.V.A. in 1980 to 1982" and "there was no question that it worked."
Despite ongoing efforts by U.V.A. and a handful of other U.S. hospitals to identify and isolate colonized patients, MRSA raced through the health care system virtually unchecked because most facilities lacked effective infection-control programs. By the 1990s, "the whole health care system became completely permeated by [MRSA]," says Farr, who for the past three decades has been a leading proponent of active detection and isolation to control superbugs. In 1995 MRSA infections accounted for 22 percent of all health care–associated staph infections, compared with only 2 percent in 1974.
Today, "close to 70 percent of staphylococcus causing infections in intensive care units are MRSA," says Fred Tenover, acting director of the CDC's National Center for Infectious Diseases Office of Antimicrobial Resistance, noting that within that average there is huge variation from one hospital to the next.
The University of Virginia is one of many exemplars of infection control in the U.S. Between 2001 to 2005, a group of 32 Pennsylvania hospitals working with the CDC slashed the rate of central lineassociated bloodstream infections (associated with catheters placed in veins) in intensive care units by 68 percent. One of the participants in that initiative, Allegheny General Hospital in Pittsburgh, reduced the total number of these infections by nearly 90 percent in one year (2003 to 2004) and the unit has recently gone nearly 18 months without an infection. The dramatic decline at Allegheny occurred despite a near doubling in the use of catheters and a steady increase in the severity of illness of patients in its intensive care unit. "Using more catheters and caring for sicker patients are not justifications for higher numbers of infections," Richard Shannon, then chair of Allegheny's department of internal medicine, told a congressional panel last year that was considering proposals designed to reduce hospital-acquired infections.
Shannon, who has since become chair of the department of medicine at the University of Pennsylvania in Philadelphia, outlined his successful campaign during a recent interview with Scientific American.com. "We took the Toyota production system and applied it to placement and maintenance of catheter insertions," and later ventilator insertions, he says. To create a perfect product, "all things have to be executed perfectly," and everyone in the organization must be on board, he says.
The same is true for infection control. In order to determine the perfect way to execute each step of placing and maintaining catheters, Shannon says he tapped the doctors, nurses and medical technicians in his hospital for advice. After developing standardized procedures for everything from putting on a hospital gown and cap to washing hands to actually placing the catheter, "we trained people and observed them" instead of just handing out a document with instructions, he notes, adding that leadership is a key component of eradicating the problem. "This will never occur," he says, "until a senior person says, 'I've had enough.'"
Despite the success of these hospitals and several others, critics say the U.S. lags far behind some countries in keeping superbugs in check. Denmark's MRSA prevalence reached 33 percent in the 1960s but steadily declined after a strict infection-control policy was implemented; it has remained below 1 percent for 25 years. In the Netherlands and parts of Scandinavia health care–associated MRSA prevalence has been maintained at 1 to 3 percent for decades through an aggressive "search and destroy" approach: Hygiene practices are strictly enforced and all high-risk patients and staff members are systematically screened for MRSA; those found to be infected or carriers are quarantined.
Many experts believe that the search-and-destroy method is the best answer to America's superbug problem. "We need to start looking for these [drug-resistant strains] on admission and putting patients in isolation," says Marcia Patrick, spokesperson for the Washington D.C–based Association for Professionals in Infection Control and Epidemiology (APIC).
Most hospitals follow CDC guidelines, which have not explicitly recommended routine active surveillance cultures to identify and isolate patients with superbugs, even though more than 140 studies have shown that MRSA and VRE can be controlled this way, Farr says.
Interestingly, the CDC advises routine HIV screening of adults, adolescents and pregnant women in health care settings, but does not recommend universal testing for MRSA, which kills more people than HIV.
Meanwhile, physicians say that it is tough to get health care workers to take even the simplest precautions such as scrubbing their hands between patients. Patients will no doubt be stunned to learn surveys show that compliance with such rules now hovers at only around 50 percent on average at medical institutions in this country.
"We have the knowledge to prevent these, and what has been lacking is the will, the energy, the pressure to do it," says former lieutenant governor of New York, Betsy McCaughey, chair of the nonprofit Committee to Reduce Infection Deaths (RID). But the climate is changing fast, she adds.
"Hospitals are moving into a new legal environment," she says. "As long as it was believed that hospital infection was the inevitable risk you faced in the hospital and nothing could be done about it, hospitals were protected from lawsuits." But that is no longer the case as more and more people come to recognize that these infections are mostly preventable.
The law itself has begun to change. U.S. Rep. Tim Murphy (R–Pa.) has proposed the Healthy Hospitals Act of 2007, which would require hospitals to publicly report their infection rates as well as provide economic incentives to those that successfully reduce their rates. Since 2003 19 states have passed legislation requiring hospitals to report their infection rates: Colorado, Connecticut, Delaware, Florida, Illinois, Maryland, Minnesota, Missouri, New Hampshire, New York, Ohio, Oregon, Pennsylvania, South Carolina, Tennessee, Texas, Virginia, Vermont and Washington. These laws vary dramatically: some states impose penalties as high as $1,000 per day for hospitals that fail to comply, whereas others have almost no enforcement power, says Lisa McGiffert, manager of Consumer Union's StopHospitalInfections.Org, a project aimed at getting states to publish infection rates of hospitals and other health care facilities. (The site provides recent information on hospital infections and an online forum where over 1,800 victims have shared their experiences. It also encourages citizens to sign petitions and write letters to hospitals and government officials.) Reporting infection rates "stimulates activity," McGiffert says. "Once a bill passes in a state, hospitals start getting better," she says, noting that it's still too early to see a cause-and-effect relationship.
But Michael Bennett, president of the lobbying group Coalition for Patients' Rights (CPR), says that "hospitals have a huge disincentive to accurately report their infections," and "there are countless ways that a reporting system can be gamed." Reporting laws are good, Bennett says, but "there is no data that I'm aware of that suggests reporting has lowered infection rates or the numbers of infections."
RID's McCaughey says that hospitals need to take the problems seriously and not skimp when it comes to forking out funds to do the job properly. In addition to saving lives, she notes that "We can show hospitals that they can be more profitable by preventing infections." She estimates that hospital infections add at least $30.5 billion a year to the nation's health care tab in hospital costs alone—enough to pay for the entire Medicare (Part D) prescription drug program. According to a recent article in The Lancet, "virtually all published analyses that have compared the cost of screening of patients on admission and using contact precautions with colonized patients" show that "the costs of caring for patients who become infected with MRSA are much greater than the costs of screening programs."
What this country needs is federal infection-control legislation derived from evidence-based best practices, Bennett says. He co-founded CPR three years ago after his father died at age 88 from a deadly infection contracted at Northwest Hospital Center and Sinai Hospital, both in the Baltimore area, while being treated for a nonlife threatening respiratory infection. Bennett is putting together a task force of scientists to draft new legislation or add teeth to existing measures that would mandate infection-control guidelines. That language would surely include active detection and isolation for the most egregiously out-of-control superbugs like MRSA. Hospitals need to "screen high-risk admissions and treat them proactively," Bennett says. "We are talking about life and death and immense human suffering that has come about through systemic negligence."
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