A 24-year-old nurse prescribed antibiotics during dental care develops severe diarrhea that does not respond to initial treatment, knocking her out of work in an oncology ward for two weeks. What happened? Occupational Clostridium difficile.

With C. diff at epidemic levels, workers may acquire the bug from patients if they take antibiotics that wipe out the commensal bacteria in the gut and open a path for the pathogen.

“I think it would be a good idea for employee health to inform personnel about this risk if they are prescribed antibiotics,” says Curtis Donskey, MD, an infectious disease physician at Louis Stokes Cleveland VA Medical Center. “I do that routinely if I prescribe antibiotics to someone working in a healthcare setting.”

With no active surveillance system for such occupational infections, there are almost certainly more occurring than the cases sporadically documented in the medical literature.

“When I give presentations and comment on the risk to healthcare personnel taking antibiotics, it is common for a physician or nurse to come up afterwards and say that they or one of their coworkers got a C. diff infection while they were working,” he says.

Donskey previously investigated some of these C. diff infections, reporting one case of a patient transporter who developed symptomatic C. diff and vancomycin-resistant Enterococcus (VRE) colonization after taking clindamycin for another condition.1 The researcher subsequently reported four additional cases of C. difficile infection in healthcare workers, all of whom were in good health with the exception of the conditions for which antibiotics were prescribed.2 All subjects developed diarrhea during antibiotic treatment or within two weeks after completing it. The cases underscore that even healthy workers may be at risk of C. diff infection after receiving short courses of relatively narrow-spectrum antibiotics. Of course, healthcare staff with underlying conditions that impair immune response are at greater risk of more serious infections.

C. diff infections can sideline healthcare workers for a prolonged period in some cases, as with the aforementioned nurse furloughed for a fortnight after taking clindamycin related to dental care.3 Her C. diff infection did not respond to initial treatment with metronidazole, but she fully recovered when switched to vancomycin.

Patients with C. diff typically have diarrhea and are indicated for contact isolation precautions requiring gloves, gowns, and other measures because the spore-forming pathogen can linger in the environment and spreads via the fecal-oral route. Thus, the PPE problems with training and compliance described in this issue of Hospital Employee Health do not bode well for control of C. diff and protection of workers.

C. diff has become one of the most prevalent and deadly healthcare-associated infections in the country, directly attributable for some 15,000 patient deaths annually, according to the Centers for Disease Control and Prevention.4 A confluence of events has led to the current C. diff epidemic, including the emergence of the highly virulent and toxigenic NAP1 strain in 2000, the misuse and overuse of antibiotics, and the difficulty of removing C. diff spores from contaminated surfaces and healthcare worker hands.

Gloves critical

In that regard, appropriate glove use by healthcare workers caring for C. diff patients is critical because the safety net of hand hygiene is much less protective. The problem — and it’s a big one — is that the alcohol hand rubs now ubiquitous in healthcare are largely ineffective against C. diff spores. Traditional soap and water fares little better. As a result, the CDC and a consensus of infection control and occupational health experts advise in compendium guidelines that glove use is critical. “Although in vivo studies demonstrate that C. difficile spores are resistant to alcohol, they also show poor log reductions (less than 2) for hand washing with soap and water,” the compendium guidelines state.5 “A 2013 study6 showed that only atypical products (e.g., ink and stain remover) could remove more than 1 log.”

The CDC currently recommends that healthcare workers “wear gloves and gowns when treating patients with C. difficile, even during short visits. Hand sanitizer does not kill C. difficile, and although hand washing works better, it still may not be sufficient alone, thus the importance of gloves.”7

C. diff can become a life-threatening infection if its toxigenic effects begin to attack the digestive system.

“Unfortunately, the type of C. diff circulating in the U.S. today produces such a powerful toxin that it can cause a truly deadly diarrhea,” says Michael Bell, MD, a medical epidemiologist in the CDC division of healthcare quality promotion. “[It’s an] intense illness that can include damage to the bowels so painful and severe that part of the colon needs to be surgically removed, a condition called megacolon.”

Norovirus, MRSA

Adding symptoms of vomiting to the bowel woes is norovirus, which can spread rapidly in explosive outbreaks that include both healthcare workers and patients. Though generally not as life threatening as C. diff, one study reported norovirus mortality rates as high as 20% in patients age 65 and older.8 The most common cause of healthcare outbreaks, norovirus frequently leads to closed hospital wards and furloughed workers. In one norovirus outbreak, 316 healthcare workers (8% of the total hospital staff) — including the only employee health professional at the facility — acquired the nasty bug.9 In another outbreak that included 265 healthcare workers and 80 patients, 13 infected workers (4.9%) required emergency department visits or hospitalization.10 Costs associated with the outbreak were estimated to be $657,644 due in part to furloughed workers and significant disruptions in patient care.

To cite one more example that underscores the importance of compliance with PPE, healthcare workers have been infected with MRSA, are frequently transiently colonized, and can become chronic carriers if the pathogen finds refuge in a body site. Transient contamination of worker hands is considered a prime source of transmission of MRSA between patients, making hand washing and PPE use critical. In 1998 healthcare personnel guidelines that are in the process of being updated, the CDC recommends that if workers have a draining lesion suspected to be MRSA, cultures should be taken and they should be excluded from patient care or food handling until the infection has been ruled out or personnel have received adequate therapy and the infection resolves.11

However, the CDC notes that employee health professionals should not routinely exclude personnel with colonization with MRSA (in the nose, hands, or other body site) from patient care or food handling unless they are linked to transmission of the pathogen. MRSA colonization is common in the anterior nares, but other sites, such as the hands, axilla, perineum, nasopharynx, and oropharynx, may also be involved. In some cases, healthcare workers become chronic MRSA carriers and can spread the bacteria to patients until their condition is detected.

One such case reported this year traced a series of MRSA surgical infections to an OR worker who was asymptomatically but chronically colonized.12 The investigation began when three surgical patients were infected with MRSA within a two-month period.

“Every time we have a surgical site infection we swab all staff that were part of the surgery, even on anyone who entered the operating room,” says lead investigator Lorraine Maze Dit Mieusement, RN, MN, CIC, an infection preventionist at Mount Sinai Hospital in Toronto.

One healthcare worker, who was present during all three SSI cases, tested positive for MRSA that matched the infecting strain by pulsed-field typing. For confidentiality reasons, the hospital is not releasing the worker’s duties in the OR and other identifying details. “The swabs we did to detect it on the healthcare worker were groin swabs, and once the healthcare worker received decolonization [treatment] the MRSA was gone,” she says.

Decolonization included a week-long treatment with mupirocin and chlorhexidine.

“So the person did the treatment for seven days — the follow-up swabs were negative and we continue to do follow up swabbing every month to make sure that they remain negative,” Dit Mieusement says. Following this discovery, previous isolates that were closely related to the infecting MRSA strain were identified from the lab database. The investigators found two additional patients with surgical site infections linked to the same worker, despite no clear evidence of breaches in PPE use and infection control precautions in any of the cases.

“We know that in the operating room [healthcare workers] can shed skin cells,” she says. “Yes, they are wearing masks and gloves, but there are parts of your face that are still exposed. You can shed some skin cells and if that gets into the air in the OR — one colony of bacteria in the surgical site can be catastrophic.”


  1. Ray AJ, Donskey CJ. Clostridium difficile infection and concurrent vancomycin-resistant Enterococcus stool colonization in a health care worker: case report and review of the literature. Am J Infect Control 2003;31:(1):54–56.
  2. Arfons L, Ray AJ, Donskey CJ, et al. Clostridium difficile Infection among Health Care Workers Receiving Antibiotic Therapy. Clin Infect Dis 2005;40(9):1384-1385.
  3. Hell M, Indra A, Huhulescu S, et al. Clostridium difficile Infection in a Health Care Worker. Clin Infect Dis 2009;48(9):1329.
  4. Lessa FC, et al. Burden of Clostridium difficile Infection in the United States. N Engl J Med 2015; 372:825-834.
  5. Ellingson, K, et al. Strategies to prevent healthcare-associated infections through hand hygiene. Infect Control Hosp Epi 2014;35: 937-960.
  6. Edmonds SL, et al. Effectiveness of hand hygiene for removal of Clostridium difficile spores from hands. Infect Control Hosp Epi 2013;34:302-305.
  7. CDC. HAIs: Clostridium difficile: Information for clinicians. Sept. 23, 2015: http://www.cdc.gov/hai/organisms/cdiff/Cdiff_clinicians.html.
  8. Harris, JP, Edmunds, WJ, Pebody, R, et al. Deaths from norovirus among the elderly, England and Wales. Emerg Infect Dis. 2008;14:1546–1552.
  9. Totaro J, Daley J, Andrews P. A norovirus outbreak among healthcare workers. Am J Infect Control 2005;33(5):117–118
  10. Johnston CP, Qiu H, Ticehurst JR, et al. Outbreak management and implications of a nosocomial norovirus outbreak. Clin Infect Dis 2007;45(5):534-540.
  11. Bolyard EA, Tablan OC, Williams WW, et al. CDC Hospital Infection Control Advisory Committee (HICPAC) Guideline for infection control in health care personnel, 1998. http://www.cdc.gov/hicpac/pdf/infectcontrol98.pdf.
  12. Dit Mieusement LM, McGeer A. Investigation of a cluster of Nosocomial MRSA Surgical Site Infections. Outbreak Investigations. Infection Prevention and Control Canada Conference. Victoria, BC, June 14-17, 2015.