“Study Links Bacteria, Long Nails, and Baby Deaths.” It’s the type of headline you’d expect to read in the National Enquirer, right next to the latest Elvis sighting. Instead, it was featured in the March 27, 2000, edition of The New York Times.

The study cited was released this past February in Infection Control and Hospital Epidemiology by a group of doctors from the Centers for Disease Control and Prevention (CDC); the Acute Disease Division of the Oklahoma State Department of Health, Oklahoma City; and the Children’s Hospital of Oklahoma in Oklahoma City. Spurred by a spike in Pseudomonas aeruginosa infections in the neonatal intensive care unit (NICU) of Children’s Hospital, the team of investigating epidemiologists ultimately linked 46 P. aeruginosa infections of critically ill newborns over a 15-month period to the hands of two nurses—one with long natural nails and one with long artificial nails. Sixteen of the babies died as a result of those infections

Nail technicians and many nail clients are no strangers to P. aeruginosa, the bacteria responsible for the not-uncommon green, mold-like stain that can develop between the artificial and natural nail. The hardy bacteria can be found in almost any setting, though it particularly likes soil and water and thrives in moist, warm, and dark environments. To the healthy individual, P. aeruginosa is relatively harmless even when it gains entrance to the body

“[Pseudomonas] is a very common organism in our environment and one that all of us are exposed to quite regularly,” observes Dr. Michael Crutcher, state epidemiologist at the Okalhoma State Department of Health and a coauthor of the study. “[Healthy individuals] are constantly exposed to [infectious organisms], but we don’t become ill all the time because we have highly sophisticated immune systems.” In individuals with weakened immune systems, however, P. aeruginosa can be deadly if it sneaks past the body’s defenses were asked to wash their hands with either a standard microbial soap and a waterless gel hand sanitizer. Incredibly, 67% of the nurses with artificial nails that had the pathogenic bacteria still had pathogens after washing and using a waterless gel hand sanitizer, compared to 26% of the group with short, natural nails harboring pathogens. These findings concern McNeil in light of a survey she did that found 12% of nurses at the University of Michigan’s Ann Arbor teaching hospital wear artificial nails.

What Dr. McNeil can’t say is how large of a role nail length plays. She and her team tried to control for nail length but discovered that, without exception in her study group, those with artificial nails wore them long while those with natural nails wore them short. On the one hand she notes that the bacteria was found in greater concentrations under the nails, which could party be due to length, but she has no doubt that artificial materials on the nail, regardless of length, are largely to blame.

“Certainly bacteria has been shown to adhere better to artificial materials than to natural nails,” she asserts. “There is concern that people who spend money on their nails spend less time and effort washing their hands because they’re concerned about damaging their nails.”

The Evidence Stacks Up

Dr. McNeil is by no means the first to examine the role of fingernails in disease transmission. The first documented study we found was published in 1988. In that study researchers cultured the nails of 10 nurses wearing artificial nails and 10 nurses with natural nails. Like Dr. McNeil, they found that artificial nails were colonized with higher levels of bacteria than natural nails.

A 1989 study delved deeper, culturing the nails of 112 nurses before and after handwashing. Even after a 10-second friction scrub the artificial nails had significantly higher levels of pathogenic bacteria. Researchers also have studied nail polish and determined that polish that is chipped or that has been worn four or more days harbors higher levels of pathogenic bacteria.

These three studies led the Association of Operating Room Nurse (AORN) in 1994 to add a segment on nail care to its Recommended Practices. In short, AORN advocates “short, dean, and healthy nails” to its membership; the policy goes on to state, “Artificial nails should not be worn within the semi-restricted and restricted areas of the practice setting.”

A report in the January/February 1988 issue of Nursing Research (“Impact of a 5-Minute Scrub on the Microbial Flora Found on Artificial, Polished, or Natural Fingernails of Operating Room Personnel”) complements Dr. McNeil’s findings. “The results of this study indicate that OR personnel with artificial nails more often harbored [pathogenic bacterial] both before and after a five minute scrub using microbial soap,” cited the authors. “Additionally, artificial nails had higher bacterial loads, as compared with natural or polished nails.”

Overall, the study findings show that the OR personnel wearing artificial nails had an increase in the variety and amount of potentially harmful bacteria,” the authors stated later in the article. “Although this study did not examine the transmission of bacteria from nails to patients, the potential for transmission….exists.” those numbers, which the CDC says increased 36% between 1975 and 1995.

One reason for the dramatic increases is that even as medical treatments have made dramatic strides in saving lives and curing disease, those some treatments have become more invasive—breathing tubes and intravenous catheters are just two common invasive treatments. Patients admitted to hospitals today are much more ill than they were 20 years ago because improved medical technology and a better understanding of the healing process have led to an increase in outpatient treatment programs.

Then there are the “super-organisms,” which are bacteria that have developed a resistance to the antibiotics to treat them. According to the CDC, at least 70% of the hospital-acquired infections that occur are caused by an organism that’s resistant to at least one antibiotic.

Hence a back-to-basics attitude among infection control personnel. With direct and indirect contact the most common form of disease transmission, handwashing practices and the correct use of gloves in health care settings has been getting a lot of attention, and with good reason. While much of the recent research on the role of fingernails in transmitting disease has examined whether proper handwashing and scrub techniques eliminate the bacteria, the simple fact is that studies show that only about 40% of health care workers (including nurses, doctors, and others with direct patient contact) follow correct handwashing procedures.

“Part of the poor compliance has been facilitated by an emphasis on using gloves as barriers, with the perception that if you wear gloves then handwashing is less important” explains Edward Wong, M.D., of the infectious disease section of the VA medical Center in Richmond, Va. “Obviously that’s not true.”

Indeed, in the Nursing Research report described earlier, the authors cited numerous studies documenting that gloves can—and do—develop microscopic teas during use, and that anywhere from 12% to 72% (depending on the brand) are defective straight out of the box.

Even with proper handwashing techniques, the experts we asked still think that long and artificial nails pose a problem in a health care setting. “I think [long nails] give the organisms an advantage of persisting under the nails and because of that they felt it was important to prohibit [health care workers] from wearing them,” Says Dr. Wong. “You can wash your hands but under the nails is a special niche with fatty acids and other organic debris that allows organisms to proliferate and be more resistant to handwashing.”

Perhaps Manicure Instead

At this time, only a few of the studies conducted on the link between artificial nails and disease transmission have been published, with the February 2000 study of the NICU outbreak being the first to line bacteria on artificial nails to actual cases of illness. However, Dr. Wong notes that while the number of cases in that particular NICU did drop dramatically, they didn’t completely go away.

“This suggests that offer factors might be involved,” he stated in a separate editorial that also appeared in the February 2000 issue of Infection Control and Hospital Epidemiology. “The case against long fingernails could have been made stronger if serial hand cultures had been obtained and had demonstrated that colonization with Pseudomonas persisted longer in nurses with long vs. short or medium fingernails,” he stated later in the same article.

“My point is that I think the evidence is there and suggestive, but not irrefutable,” Dr. Wong told NAILS. Now that artificial nails have made the radar screen of investigators and researchers, however, more in-depth studies are sure to come. In the meantime, the CDC has yet to make any recommendations regarding artificial nails in the health care setting, but an increasing number of hospitals are independently adopting policies banning them as awareness grows. “I don’t think it’s necessary to ban artificial nails,” says Dr. McNeil. “I think it’s important to educate. Nurses’ first concern is for patients, and we’re hoping that if enough things come out to make them aware then they’ll make the choice on their own.”

Even as they recommended to hospitals that artificial nails be banned for anyone with patient contact, the doctors and nurses we interviewed emphasized that they don’t think artificial nails pose a risk outside of health care settings. As for nail technicians, Dr. McNeil made special note of research that demonstrates that a 10-second application of an alcohol-based, waterless hand sanitizer rids bacterial from the nails better than soap and water. While nail technicians must abide by the rules of their state boards of cosmetology, you can certainly incorporate waterless hand sanitizers as an added step, as well as recommend them to you clients-both those with artificial and natural nails.  

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