Within the context of this framework, harm refers primarily to developing an infection; we have extended it more broadly, here, to include becoming colonized with an emerging highly antibiotic-resistant pathogen (eg, carbapenem-resistant Enterobacteriaceae [CRE]). This type of notification often takes the form of a conversation with the patient or their surrogate, as part of routine clinical care.

When an outbreak or infection control breach is first suspected or identified, the extent of patient harm is usually not evident. At-risk patients might have already developed signs or symptoms of infection but either have not sought care or have presented at a facility other than the index facility. Alternatively, at-risk patients might need to undergo screening (eg, surveillance cultures or bloodborne pathogen testing) or be made aware of signs and symptoms that could indicate infection. Signs and symptoms of infection with nontuberculous mycobacteria (NTM), for example, may take a long time to manifest following exposure. Further, most patients with newly acquired hepatitis B virus or hepatitis C virus (HCV) infection do not manifest signs or symptoms of acute infection; likewise, early signs and symptoms of acute human immunodeficiency virus (HIV) infection may be mistaken for a self-limited viral illness. In situations where bloodborne pathogen risk is present, patient notification is important so patients can obtain appropriate testing.¹⁵ For some pathogens, testing before the development of signs and symptoms of infection might not be reliable; however, notification remains advisable so patients can be counseled about monitoring for signs and symptoms and the action(s) to take if they develop. In either situation (ie, proactive testing, counseling for signs and symptoms), patients should receive plain language information explaining why they are being contacted as well as any actions they might need to take to protect others (eg, advising patients with respiratory infection to practice respiratory hygiene and cough etiquette). This outreach might also be important early in an investigation to support case finding, helping to confirm the presence of an outbreak or better define its magnitude and scope. Of note, identifying at-risk patients can be challenging compared with identifying those who have been harmed (trigger 1) or those who have experienced an alteration in care (trigger 3) when relevant exposures are not well documented in patient charts or billing records.

Patients who develop an infection and, often, patients who become colonized with an antibiotic-resistant pathogen will experience an alteration in care. This might include receipt of antibiotics that they would not otherwise have received or use of additional infection control precautions (eg, the use of gowns or masks, restricting the patient to their room) during the current or future health care encounters. Further, alterations in care might not be isolated only to patients who develop infection or colonization; in a long-term care facility, for example, outbreak control measures may include decisions to restrict visitors or limit group activities, which could affect all facility residents.¹⁶

A local hospital infection preventionist notified the health department of 4 patients admitted to the hospital with Pseudomonas aeruginosa bloodstream infection (BSI); 2 of these patients also had Klebsiella pneumoniae BSI.¹⁹ All 4 patients had an indwelling infusion port and were receiving infusion services at a physician-owned outpatient oncology clinic. As the health department’s investigation began, 4 additional clinic patients were admitted to the hospital with catheter-associated BSIs; the clinic was closed under a public health order. All current patients receiving infusion services at the clinic were contacted by the health department, informed of the outbreak, and assessed for symptoms of infection; their primary care physicians were also notified of the risk and asked to monitor for and report any infections. Communication was also maintained with area hospitals to identify additional hospital admissions for these patients. An assessment of infection control practices identified serious longstanding breaches in handling of injectable medications, including overt reuse of syringes for more than 1 patient. A letter was sent to all patients who had ever received care at the clinic informing them of their potential exposure to unsafe injection practices and advising them to seek bloodborne pathogen testing, which was offered for free at county health clinics. All 3 notification triggers applied in this scenario.

A cluster of 4 patients with infections caused by Staphylococcus aureus strains that had a similar morphology and antibiogram were identified in a 7-day period.²⁰ An investigation was launched by the facility and steps were taken to limit further spread within the unit, including use of screening cultures; cohorting; Transmission-Based Precautions for patients found to be colonized or infected; and mupirocin treatment for patients and staff. Parents of patients in the neonatal intensive care unit were given a letter notifying them of the outbreak and outlining the rationale for screening cultures, cohorting, and mupirocin treatment. They were also advised regarding recommended infection prevention practices (eg, hand hygiene) to prevent transmission on the unit. All 3 notification triggers applied in this scenario.

A nursing home identified acute respiratory illness among 4 residents on the same unit. The cause of the infections was unknown. The nursing home immediately contacted the health department and implemented measures to prevent further transmission. Infected residents were placed on Contact and Droplet Precautions (including eye protection to be worn by health care personnel caring for infected residents), in either a single room or cohorted with other infected residents. All residents and health care personnel were notified, in person and through posted signs, about the emergence of respiratory infections in the facility and the need to monitor for and immediately report any signs or symptoms of respiratory infection. Active surveillance for new infections was also implemented. Although the source of the outbreak was unknown, unvaccinated residents and staff were offered influenza vaccine. New admissions to the unit were suspended and group activities were cancelled, including meals in the dining hall. Signs and supplies emphasizing respiratory hygiene and cough etiquette were posted throughout the facility; letters were sent to family members informing them about the outbreak and reminding them not to visit when ill. All 3 notification triggers applied in this scenario.

The health department received a report of a single case of fungal meningitis in an immunocompetent adult after an epidural steroid injection at an outpatient clinic.²¹ Initially, the health department conducted outreach to the clinic and area hospitals to search for additional cases and determine if an outbreak existed or if this was an isolated infection. A multistate outbreak was ultimately confirmed and the source of the infections (contaminated pharmacy-compounded steroid medication) was identified. Early information suggested that presenting symptoms of fungal meningitis were often vague, leading to delayed diagnosis and high risk of mortality and other severe outcomes. An aggressive effort was then undertaken by health departments and the facilities that administered the contaminated medications to directly contact exposed patients (eg, by telephone), informing them of the signs and symptoms of infection that should prompt them to seek care. In addition, public health investigators provided physicians with guidance that would allow them to properly diagnose and treat the infections. Notification of patients who had already developed infection was also critical to ensure they and their physicians knew their infection was likely fungal in origin and to direct them to treatment guidance. Notification triggers 1 and 2 primarily applied in this scenario.

A cluster of invasive NTM infections among open-heart surgery patients at a single hospital was reported to public health.²² The ensuing investigation identified an association between the infections and exposure to the LivaNova 3T heater-cooler device used during cardiac surgery procedures requiring cardiopulmonary bypass (consistent with a recent report from Switzerland). The hospital notified approximately 1,300 open heart-surgery patients who were exposed to the device over the preceding four years. Patients were counseled about the signs and symptoms that could signal the presence of NTM infection; similar guidance was provided to area physicians. The facility also contacted patients who had been previously diagnosed with an NTM infection, along with the family members of case-patients who had died, to notify them about the infections and provide additional information. The likely source of the NTM, Mycobacterium chimaera, was later found to be contamination of the 3T heater-cooler device at the manufacturing site, suggesting that additional cardiac surgery patients at other facilities using the same device were at risk. Patients infected with M. chimaera through open-chest cardiac surgery can develop general or nonspecific symptoms that can take months to years to develop; diagnosis of these infections can be missed or delayed, making these infections more difficult to treat. Ultimately, CDC recommended that all facilities in the United States using 3T heater-cooler devices (whether or not they had a documented case) notify (by letter) all patients potentially exposed to these devices to counsel them about signs and symptoms of infection to ensure prompt recognition and treatment of these serious infections.²³ Notification triggers 1 and 2 primarily applied in this scenario.

Six patients with a history of admission to the same hospital had New Delhi metallo-β-lactamase (NDM)-producing CRE isolated from clinical cultures over a 5-month period.²⁴ An investigation to identify the source of the organism and to assess for transmission within the facility was launched. Patients epidemiologically linked to case-patients (eg, roommates, patients admitted to the same ward where the first patient was treated) were notified and offered CRE rectal screening. A history of endoscopic retrograde cholangiopancreatography procedures involving a duodenoscope was strongly associated with being a case-patient. Review of reprocessing procedures did not identify protocol lapses; however, NDM-producing Escherichia coli and Klebsiella pneumoniae carbapenemase-producing K. pneumoniae were isolated from cultures obtained from the duodenoscope used on several case-patients. Based on these findings, the facility notified all patients who underwent a procedure with any duodenoscope at the hospital during the outbreak period. Patients were informed about the potential exposure to CRE and offered CRE rectal screening and bloodborne pathogen testing. Testing identified an additional 27 patients colonized with CRE; bloodborne pathogen testing did not identify previously undiagnosed infections among patients who returned for screening. Notification triggers 1 and 2 primarily applied in this scenario.

A nurse noticed debris at the biopsy-port cap of a bronchoscope that had been reprocessed and was about to be used for a patient procedure in a hospital bronchoscopy suite. This prompted a review of bronchoscope reprocessing procedures, which identified several infection control breaches. The bronchoscope channel was not brushed as part of manual cleaning by a reprocessing technician who had been working in the suite for the last month. Further, the facility had recently purchased a new automated endoscope reprocessor (AER). The AER connectors were not compatible with the bronchoscope, which meant the scope channel was not flushed with glutaraldehyde disinfectant solution or rinsed. The water filter in the new AER had not been changed at the interval recommended by the manufacturer. The facility contacted the health department for assistance with a risk assessment, which concluded there could be risk of both bacterial and bloodborne pathogen infections. The facility sent letters to all patients who had undergone a bronchoscopy over the prior 8 months, which was when the new AER had been purchased. Patients were informed about the breaches in reprocessing and counseled that the breaches may have put them at risk of infection. Patients were informed about the signs and symptoms of respiratory infection and were also advised to return to the hospital for bloodborne pathogen testing. Notification trigger 2 applied in this scenario.

A routine assessment of infection control at an outpatient urology clinic identified multiple breaches in cystoscope reprocessing. The facility failed to soak the cystoscope in cleaning solution for the recommended length of time; they did not immerse the entire cystoscope in the glutaraldehyde solution that was used to perform high-level disinfection; the cystoscope was rinsed in a bath of initially sterile water that was only replaced when it became cloudy or began to smell. The facility contacted the health department to discuss the risks posed by identified breaches; the health department recommended a patient notification be performed. The facility sent letters to all patients who had undergone cystoscopy at the clinic since the last routine assessment had occurred (6 months prior). Patients were informed that the identified breaches could have placed them at increased risk of developing a bacterial infection following their procedure. They were instructed to contact the clinic if they developed signs and symptoms of a urinary tract or BSI. Patients who had undergone cystoscopy in the prior 2 weeks were also contacted by phone as, if infection were to occur, it would most likely manifest within 2 weeks following the procedure. The infection control breaches were not believed to pose risk of bloodborne pathogen transmission; however, the clinic agreed to provide such testing if a patient requested it. Notification trigger 2 applied in this scenario.

A patient filed a complaint with the state dental board about concerning practices at a dental clinic. The dental board, in collaboration with the health department, conducted a site visit at the clinic. During the site visit, they observed multiple breaches in infection control including: the autoclave that was reportedly used to sterilize dental instruments was broken—the dentist could not provide maintenance records for the autoclave to demonstrate when it had last been properly working and there were no logs to show that equipment had been sterilized; in lieu of the autoclave, dental staff wiped the used dental equipment with a bleach wipe; “clean” dental equipment was stored, unwrapped, next to the sink where dirty equipment was cleaned. Based on findings from the site visit, the dental clinic was closed and the dentist’s license was suspended. At this point, the dentist refused to cooperate further with the investigators or turn over patient records. Because of the delay in obtaining patient records, the health department elected to move forward with a public notification through the local media advising any patient who had ever received care from the dentist to seek bloodborne pathogen testing from their primary care physician. Guidance on recommended tests was posted on the health department website. In addition, patients who did not have a primary care provider were offered testing at the local health department. Notification trigger 2 applied in this scenario.

As part of an accreditation survey, surveyors found that a hospital’s newly acquired satellite clinic was not performing biologic indicator testing as part of their instrument sterilization process. This raised concerns that the lack of testing meant that sterility of instruments could not be guaranteed and was reported to the state health department. The health department assisted with a risk assessment and performed a detailed review of the clinic’s sterilization practices. Following a surgical procedure, instruments were immediately transported in a closed container to the reprocessing room. Appropriate manual cleaning with a brush and enzymatic cleaner was performed; instruments were rinsed, wrapped, and steam sterilized following recommended parameters (eg, time, temperature); mechanical and chemical indicators were used to monitor the sterilization process. The facility had never used biologic indicators. During the health department visit, a typical sterilization cycle was run with a biological indicator; the biologic indicator was negative. The facility was instructed to commence using biologic indicators at least weekly. Based on the infection control assessment, a risk to patients was not identified. The facility was advised, for transparency, they could consider notifying patients; however, they elected not to perform a patient notification. No notification triggers were clearly met in this scenario.

A hospital telemetry unit nurse was observed to frequently leave a partially filled syringe of saline flush near a computer work station.²⁵ The hospital questioned the nurse about this practice and she reported reusing syringes for more than 1 patient over the previous 6 months. She erroneously believed this was a safe, cost-saving measure if no fluids were withdrawn into the syringe before injection. At the time the breach was identified, the facility was unaware of any infections associated with the practice. The hospital notified all potentially exposed patients (by both certified and registered mail) and provided free bloodborne pathogen testing. As a result of the outreach, HCV transmission was documented as having occurred on at least one occasion from a patient with known chronic infection to a susceptible patient whose stay overlapped with the source patient. Notification trigger 2 applied in this scenario.

An operating room nurse observed a surgical technician taking a syringe filled with fentanyl and replacing it with a syringe containing a similar appearing liquid. The technician was immediately confronted and the incident was reported to law enforcement and public health authorities. The technician admitted he had been stealing syringes of fentanyl and swapping them with syringes of saline over the prior month. He stated he always replaced the fentanyl syringes with new syringes that he filled with sterile saline from a multidose vial he kept in his locker. He was asked to undergo bloodborne pathogen testing and was found to be immune by vaccination to hepatitis B virus but negative for HCV and HIV. The hospital elected to contact all patients who had surgery on the dates the technician was working since he was hired (4 months prior). The notification letter informed patients that drug tampering by an employee had been identified and, because of the employee’s behavior, they may not have received fentanyl during their procedure. Patients were advised that the technician had tested negative for bloodborne pathogens and, based on his reported method of diversion, there was not believed to be a risk of infection. However, because they were relying on self-reported, unconfirmed behavior, they could not be certain there was not a risk (eg, patient-to-patient transmission of bloodborne pathogens from reused syringes or bacterial infections from nonsterile saline). Patients were encouraged to contact the hospital if they developed any possible signs or symptoms of bacterial infection (eg, fever, chills, pain, or redness at the injection site) and advised that, if they had concerns, the hospital would provide bloodborne pathogen testing at no charge. The hospital also adjusted patient bills to remove charges for sedating medications used during their procedures. Notification triggers 1 and 2 applied in this scenario.