The 2014-2016 Ebola virus disease (Ebola) epidemic in West Africa underscores the need for health care infection prevention and control (IPC) practices to be implemented properly and consistently to interrupt transmission of pathogens in health care settings to patients and health care workers. Training and assessing IPC practices in general health care facilities not designated as Ebola treatment units or centers became a priority for CDC as the number of Ebola virus transmissions among health care workers in West Africa began to affect the West African health care system and increasingly more persons became infected. CDC and partners developed policies, procedures, and training materials tailored to the affected countries. Safety training courses were also provided to U.S. health care workers intending to work with Ebola patients in West Africa. As the Ebola epidemic continued in West Africa, the possibility that patients with Ebola could be identified and treated in the United States became more realistic. In response, CDC, other federal components (e.g., Office of the Assistant Secretary for Preparedness and Response) and public health partners focused on health care worker training and preparedness for U.S. health care facilities. CDC used the input from these partners to develop guidelines on IPC for hospitalized patients with known or suspected Ebola, which was updated based on feedback from partners who provided care for Ebola patients in the United States. Strengthening and sustaining IPC helps health care systems be better prepared to prevent and respond to current and future infectious disease threats.The activities summarized in this report would not have been possible without collaboration with many U.S. and international partners (http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/partners.html).

Zika virus transmission was detected in the Region of the Americas (Americas) in Brazil in May 2015, and as of March 21, 2016, local mosquito-borne transmission of Zika virus had been reported in 32 countries and territories in the Americas, including Puerto Rico and the U.S. Virgin Islands.* Most persons infected with Zika virus have a mild illness or are asymptomatic. However, increasing evidence supports a link between Zika virus infection during pregnancy and adverse pregnancy and birth outcomes (1), and a possible association between recent Zika virus infection and Guillain-Barré syndrome has been reported (2). Although Zika virus is primarily transmitted through the bite of Aedes species of mosquitoes, sexual transmission also has been documented (3). Zika virus RNA has been detected in a number of body fluids, including blood, urine, saliva, and amniotic fluid (3-5), and whereas transmission associated with occupational exposure to these body fluids is theoretically possible, it has not been documented. Although there are no reports of transmission of Zika virus from infected patients to health care personnel or other patients, minimizing exposures to body fluids is important to reduce the possibility of such transmission. CDC recommends Standard Precautions in all health care settings to protect both health care personnel and patients from infection with Zika virus as well as from blood-borne pathogens (e.g., human immunodeficiency virus [HIV] and hepatitis C virus [HCV]) (6). Because of the potential for exposure to large volumes of body fluids during the labor and delivery process and the sometimes unpredictable and fast-paced nature of obstetrical care, the use of Standard Precautions in these settings is essential to prevent possible transmission of Zika virus from patients to health care personnel.

OBJECTIVE: To measure the association between the disinfection of municipal drinking water with monochloramine and the occurrence of hospital-acquired legionnaires' disease (LD). SETTING: One hundred sixty-six U.S. hospitals. DESIGN: Survey of 459 members of the Society for Healthcare Epidemiology of America (SHEA) for hospital features; endemicand outbreak-related, hospital-acquired LD; the source of the hospital water supply; and the methods of disinfection used by the hospitals and municipal water treatment plants. RESULTS: SHEA members representing 166 (36%) of 459 hospitals responded; 33 (20%) reported one or more episodes of hospital-acquired LD during the period from 1994 to 1998 and 23 (14%) reported an outbreak of hospital-acquired LD during the period from 1989 to 1998. Hospitals with an occurrence of hospital-acquired LD had a higher census (median, 319 vs 221; P = .03), more acute care beds (median, 500 vs 376; P = .04), and more intensive care unit beds (median, 42 vs 24; P = .009) than did other hospitals. They were also more likely to have a transplant service (74% vs 42%; P = .001) and to perform surveillance for hospital-acquired disease (92% vs 61%; P = .001). After adjustment for the presence of a transplant program and surveillance for legionnaires' disease, hospitals supplied with drinking water disinfected with monochloramine by municipal plants were less likely to have sporadic cases or outbreaks of hospital-acquired LD (odds ratio, 0.20; 95% confidence interval, 0.07 to 0.56) than were other hospitals. CONCLUSION: Water disinfection with monochloramine by municipal water treatment plants significantly reduces the risk of hospital-acquired LD (Infect Control Hosp Epidemiol 2003;24:569-574). Approximately 8,000 to 18,000 cases of legionnaires' disease occur in the United States each year. Of these cases, 80% to 90% are sporadic, whereas 10% to 20% occur as part of an outbreak. Thirty-five percent of the cases reported to the Centers for Disease Control and Prevention during the period from 1980 to 1998 were acquired in hospitals, and approximately 30% of these cases were associated with an outbreak. The overall fatality rate for cases of legionnaires' disease reported to the Centers for Disease Control and Prevention was 20% and the fatality rate for reported cases of hospital-acquired legionnaires' disease was 28%. Legionnaires' disease is caused by numerous species of Legionella, bacteria that are ubiquitous in natural and man-made aquatic environments. Acquisition of legionnaires' disease usually occurs following the aspiration or inhalation of aerosols from contaminated potable water or cooling towers. Most hospital-acquired outbreaks of legionnaires' disease have been associated with the contamination of hospital drinking water with Legionella species. Efforts to prevent hospital-acquired legionnaires' disease have focused on increasing the temperature of hot water and the supplemental chlorination of drinking water. Although these measures may be effective in controlling the growth of Legionella species in drinking water systems, high water temperatures may result in scalding injuries and supplemental chlorination may hasten the development of corrosion and leaks in plumbing systems. The long-term efficacy of alternative methods for controlling and eradicating legionellae in hospital water systems (eg, ozone, ultraviolet light, and copper-silver ionization) has not been determined. Therefore, guidelines of the Healthcare Infection Control Practices Advisory Committee recommend performing surveillance for legionnaires' disease among patients and eliminating potential sources if hospital-acquired disease is suspected. Disinfection of municipal drinking water is accomplished in two stages. The goal of primary disinfection is to eradicate microorganisms from raw water entering the treatment plants and the goal of secondary (residual) disinfection is to prevent subsequent new growth of Drs. Heffelfinger, Kool, and Whitney are from the Respiratory Diseases Branch, Division of Bacterial and Mycotic Diseases; and Dr. Fridkin, Mr. Hageman, and Mr. Carpenter are from the Division of Healthcare Quality Promotion, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia. Dr. Fraser is from the Division of Infectious Diseases, Department of Medicine, Washington University Medical Center, St. Louis, Missouri. Address reprint requests to Cynthia G. Whitney, MD, MPH, Centers for Disease Control and Prevention, 1600 Clifton Road, MS C-02, Atlanta, GA 30333. 570 INFECTION CONTROL AND HOSPITAL EPIDEMIOLOGY August 2003 microorganisms in the water distribution systems. Monochloramine, formed when ammonia and free chlorine are combined in water, has been used as a residual disinfectant for drinking water since 1916.Monochloramine is an effective residual disinfectant because it is more stable than free chlorine, allowing active concentrations to be maintained throughout larger areas of water system distribution at a decreased cost; monochloramine also has better penetration into the biofilm that harbors microorganisms, including Legionella.Two previous studies suggest that residual disinfection with monochloramine by municipal water treatment plants may have a protective effect against outbreaks of hospital-acquired legionnaires' disease.The aim of this study was to quantify the association between the residual disinfection of municipal water with monochloramine and the occurrence of either endemicor outbreak-related, hospital-acquired legionnaires' disease among a representative sample of hospitals in the United States.

Data on the interaction between methicillin-resistant Staphylococcus aureus (MRSA) colonization and clinical infection are limited. During 2007-2008, we enrolled HIV-infected adults in Atlanta, Georgia, USA, in a prospective cohort study. Nares and groin swab specimens were cultured for S. aureus at enrollment and after 6 and 12 months. MRSA colonization was detected in 13%-15% of HIV-infected participants (n = 600, 98% male) at baseline, 6 months, and 12 months. MRSA colonization was detected in the nares only (41%), groin only (21%), and at both sites (38%). Over a median of 2.1 years of follow-up, 29 MRSA clinical infections occurred in 25 participants. In multivariate analysis, MRSA clinical infection was significantly associated with MRSA colonization of the groin (adjusted risk ratio 4.8) and a history of MRSA infection (adjusted risk ratio 3.1). MRSA prevention strategies that can effectively prevent or eliminate groin colonization are likely necessary to reduce clinical infections in this population.

Background: Recent outbreaks in ambulatory care settings have highlighted infection control breaches as risk factors for disease transmission. In May 2009, 3 patients were hospitalized with severe methicillin-susceptible Staphylococcus aureus (MSSA) infections after receiving epidural injections at a West Virginia outpatient pain clinic.Methods: We conducted a retrospective cohort study evaluating clinic patients who received injections during a 3-week period. A case was defined as laboratory-confirmed infection or clinical evidence of infection <= 14 days after a patient received an injection. Infection control procedures were assessed. MSSA isolates from patient infections and clinic staff nasal swabs were genotyped by using pulsed-field gel electrophoresis.Results: Eight (7%) of 110 cohort patients met the case definition; 6 (75%) cases were laboratory confirmed. Eight (12%) of 69 patients who received epidural injections were case patients compared with none of the other 41 patients (P=.02). During procedures, staff use of face masks and preparation of patient skin were suboptimal; epidural injection syringes were reused to access shared medication vials. MSSA isolates from 2 patients and 1 staff member were indistinguishable by pulsed-field gel electrophoresis.Conclusion: Infection control breaches likely facilitated MSSA transmission to patients receiving epidural injections. Adhering to correct infection control practices in ambulatory care settings is critical to prevent disease transmission. Published by Elsevier Inc. on behalf of the Association for Professionals in Infection Control and Epidemiology, Inc.

Pregnant women and their newborn infants are at increased risk for influenza-associated complications, based on data from seasonal influenza and influenza pandemics. The Centers for Disease Control and Prevention (CDC) developed public health recommendations for these populations in response to the 2009 H1N1 pandemic. A review of these recommendations and information that was collected during the pandemic is needed to prepare for future influenza seasons and pandemics. The CDC convened a meeting entitled "Pandemic Influenza Revisited: Special Considerations for Pregnant Women and Newborns" on August 12-13, 2010, to gain input from experts and key partners on 4 main topics: antiviral prophylaxis and therapy, vaccine use, intrapartum/newborn (including infection control) issues, and nonpharmaceutical interventions and health care planning. Challenges to communicating recommendations regarding influenza to pregnant women and their health care providers were also discussed. After careful consideration of the available information and individual expert input, the CDC updated its recommendations for these populations for future influenza seasons and pandemics.

Vancomycin-resistant Staphylococcus aureus (VRSA) infections, which are always methicillin-resistant, are a rare but serious public health concern. We examined 2 cases in Michigan in 2007. Both patients had underlying illnesses. Isolates were vanA-positive. VRSA was neither transmitted to or from another known VRSA patient nor transmitted from patients to identified contacts.

We evaluated the potential effects of a hypothetical vaccine in preventing invasive methicillin-resistant Staphylococcus aureus (MRSA) disease in the United States. Using an active, population-based surveillance program, we estimated baseline disease rates in the United States and compared three distinct vaccination strategies which targeted adults > or =65 years of age, persons at risk for recurrent invasive infection, and patients at hospital discharge. The strategies were projected to reduce the burden of invasive MRSA disease by 12.1%, 13.9% and 17.6%, respectively; with the strategy of vaccinating both adults > or =65 years of age and all adults at hospital discharge having the greatest impact per dose. Our data suggest that availability of an effective S. aureus vaccine could result in substantial reductions in invasive MRSA disease incidence. As candidate vaccines are evaluated, these data will be important in determining the optimal vaccination strategy.

OBJECTIVE. Pediatric influenza-associated death became a nationally notifiable condition in the United States during 2004. We describe influenza-associated pediatric mortality from 2004 to 2007, including an increase of Staphylococcus aureus coinfections.METHODS. Influenza-associated pediatric death is defined as a death of a child who is younger than 18 years and has laboratory-confirmed influenza. State and local health departments report to the Centers for Disease Control and Prevention demographic, clinical, and laboratory data on influenza-associated pediatric deaths.RESULTS. During the 2004-2007 influenza seasons, 166 influenza-associated pediatric deaths were reported (n = 47, 46, and 73, respectively). Median age of the children was 5 years. Children often progressed rapidly to death; 45% died within 72 hours of onset, including 43% who died at home or in an emergency department. Of 90 children who were recommended for influenza vaccination, only 5 (6%) were fully vaccinated. Reports of bacterial coinfection increased substantially from 2004-2005 to 2006-2007 (6%, 15%, and 34%, respectively). S aureus was isolated from a sterile site or endotracheal tube culture in 1 case in 2004-2005, 3 cases in 2005-2006, and 22 cases in 2006-2007; 64% were methicillin-resistant S aureus. Children with S aureus coinfection were significantly older and more likely to have pneumonia and acute respiratory distress syndrome than those who were not coinfected.CONCLUSIONS. Influenza-associated pediatric mortality is rare, but the proportion of S aureus coinfection identified increased fivefold over the past 3 seasons. Research is needed to identify risk factors for influenza coinfection with invasive bacteria and to determine the impact of influenza vaccination and antiviral agents in preventing pediatric mortality.

BACKGROUND:This report compares the clinical characteristics, epidemiologic investigations, infection-control evaluations, and microbiologic findings of all 7 of the cases of vancomycin-resistant Staphylococcus aureus (VRSA) infection in the United States during the period 2002-2006.METHODS:Epidemiologic, clinical, and infection-control information was collected. VRSA isolates underwent confirmatory identification, antimicrobial susceptibility testing, pulsed-field gel electrophoresis, and typing of the resistance genes. To assess VRSA transmission, case patients and their contacts were screened for VRSA carriage.RESULTS:Seven cases were identified from 2002 through 2006; 5 were reported from Michigan, 1 was reported from Pennsylvania, and 1 was reported from New York. All VRSA isolates were vanA positive and had a median vancomycin minimum inhibitory concentration of 512 microg/mL. All case patients had a history of prior methicillin-resistant S. aureus and enterococcal infection or colonization; all had several underlying conditions, including chronic skin ulcers; and most had received vancomycin therapy prior to their VRSA infection. Person-to-person transmission of VRSA was not identified beyond any of the case patients. Infection-control precautions were evaluated and were consistent with established guidelines.CONCLUSIONS:Seven patients with vanA-positive VRSA have been identified in the United States. Prompt detection by microbiology laboratories and adherence to recommended infection control measures for multidrug-resistant organisms appear to have prevented transmission to other patients.

Objective:Methicillin-resistant Staphylococcus aureus (MRSA) strains have emerged in the community, causing disease among healthy people lacking traditional risk factors for MRSA infection. This article describes an outbreak of MRSA among healthy full-term newborns.Design:Cases were identified and corresponding medical information collected. Telephone interviews were conducted with mothers of cases ands surveillance cultures from mothers and newborns were performed. MRSA isolates were genotyped.Setting:Hospital in Chicago, Illinois, USA.Participants:Newborns, their mothers and hospital healthcare workers.Intervention:Nursery infection control practices were enhanced. The MRSA-colonised healthcare workers received intranasal mupirocin.Main outcome:Within 4–23 days of birth, 11 newborns were identified with pustules, vesicles or blisters located on the head, groin, perineum, ears, legs, chin and trunk. All received antimicrobials and recovered without incident.Results:None of 432 peripartum women, one of 399 newborns, and two of 135 healthcare workers were nasal MRSA carriers. Available isolates from six patients, two healthcare workers, and one from an MRSA-colonised newborn were similar by pulsed-field gel electrophoresis. Other than contact with the hospital, no common exposures of MRSA transmission were identified.Conclusions:MRSA strains that initially emerged in the community are now causing disease in healthcare settings. Providers should be aware that MRSA can cause skin infections among healthy newborns. Adherence to standard infection control practices is important to prevent transmission of MRSA in nurseries.

STUDY OBJECTIVE:Staphylococcus aureus is a cause of community-acquired pneumonia that can follow influenza infection. In response to a number of cases reported to public health authorities in early 2007, additional case reports were solicited nationwide to better define S. aureus community-acquired pneumonia during the 2006 to 2007 influenza season. METHODS:Cases were defined as primary community-acquired pneumonia caused by S. aureus occurring between November 1, 2006, and April 30, 2007. Case finding was conducted through an Emerging Infections Network survey and through contacts with state and local health departments. RESULTS:Overall, 51 cases were reported from 19 states; 37 (79%) of 47 with known susceptibilities involved infection with methicillin-resistant S. aureus (MRSA). The median age of case patients was 16 years, and 44% had no known pertinent medical history. Twenty-two (47%) of 47 case patients with information about other illnesses were diagnosed with a concurrent or antecedent viral infection during their illness, and 11 of 33 (33%) who were tested had laboratory-confirmed influenza. Of the 37 patients with MRSA infection, 16 (43%) were empirically treated with antimicrobial agents recommended for MRSA community-acquired pneumonia. Twenty-four (51%) of 47 patients for whom final disposition was known died a median of 4 days after symptom onset. CONCLUSION:S. aureus continues to cause community-acquired pneumonia, with most reported cases caused by MRSA and many occurring with or after influenza. In this series, patients were often otherwise healthy young people and mortality rates were high. Further prospective investigation is warranted to clarify infection incidence, risk factors, and preventive measures.

A vancomycin-intermediate Staphylococcus aureus (VISA) isolated from the blood of a 46-year-old patient with endocarditis was determined to be pulsed-field type USA300, daptomycin nonsusceptible, and positive for the Panton-Valentine leukocidin genes. Development of the VISA phenotype does not appear limited to traditional health care strains of S. aureus.

Objectives After the Georgia Department of Human Resources Division of Public Health was notified about 4 patients who were hospitalized with Pseudomonas aeruginosa infections after outpatient transrectal ultrasound-guided prostate biopsies in July 2005, we investigated the cause Of, and risk factors for, the infections.Methods We enhanced surveillance for additional cases, reviewed medical records, evaluated biopsy equipment and infection control practices, and collected environmental samples. Transrectal ultrasound-guided prostate biopsy procedures were discontinued during the investigation.Results A total of 4 cases were identified. All patients were men aged 57 to 71 years. All 4 recovered with antimicrobial therapy. P. aeruginosa was isolated from the narrow lumen of the steel biopsy needle guide that had been soaking in high-level disinfectant for several days. The needle guide isolate and three available clinical isolates were indistinguishable by pulsed-field gel etectrophoresis. A review of the reprocessing procedures of the biopsy needle guide revealed that it was disinfected by submersion in high-level disinfectant rather than sterilization, the reprocessing procedure recommended by the manufacturer. Manual cleaning of the lumen was limited to flushing. After disinfection, the guide was rinsed with nonsterile tap water.Conclusions The outbreak resulted from a contaminated needle guide. The needle guide reprocessing procedures were inadequate. Potential causes of P. aeruginosa contamination include the tack of adequate manual cleaning before disinfection, failure to sterilize the needle guide, and the use of a tap-water rinse after disinfection. Clinicians performing transrectal ultrasound -guided prostate biopsy procedures should follow the manufacturers' needle guide reprocessing recommendations or use disposable needle guides.

Objectives: We conducted a retrospective study to determine trends and characteristics of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) in Hawaii.Methods: We reviewed medical records of patients with MRSA infections during July 2001-June 2003 in four healthcare facilities. A case was defined as a patient with MRSA infection (colonization excluded), diagnosed in ambulatory settings or <= 48 h after hospitalization, without previous MRSA or healthcare risk factors. Pulsed-field gel electrophoresis (PFGE) and typing of resistance and toxin genes was performed in 40 MRSA isolates.Results: CA-MRSA infections increased from 28 (23% of MRSA infections) to 65 (32%) per quarter over the 2-year period (P < 0.05). Pacific islanders accounted for 51% of 389 case-patients, but only 24% of the Hawaii population. In the pediatric hospital, Pacific Islanders represented 76% of 90 case-patients versus 35% of the hospital population. Hospital admission, required for 40% (154/389), was associated with prior antimicrobial treatment (P < 0.01). The staphylococcal cassette chromosome mec type IV was detected in 38/40 isolates; 31 isolates carried Panton-Valentine leukocidin genes and 22 belonged to the same staphylococcal lineage.Conclusions: In Hawaii, prevention strategies for CA-MRSA infections should focus on Pacific Islanders. CA-MRSA infections in Hawaii appear to be related to strains causing disease throughout the United States. (c) 2006 The British Infection Society. Published by Elsevier Ltd. All rights reserved.

During the 2003-04 influenza season, 17 cases of Staphylococcus aureus community-acquired pneumonia (CAP) were reported from 9 states; 15 (88%) were associated with methicillin-resistant S. aureus (MRSA). The median age of patients was 21 years; 5 (29%) had underlying diseases, and 4 (24%) had risk factors for MRSA. Twelve (71%) had laboratory evidence of influenza virus infection. All but 1 patient, who died on arrival, were hospitalized. Death occurred in 5 (4 with MRSA). S. aureus isolates were available from 13 (76%) patients (11 MRSA). Toxin genes were detected in all isolates; 11 (85%) had only genes for Panton-Valentine leukocidin. All isolates had community-associated pulsed-field gel electrophoresis patterns; all MRSA isolates had the staphylococcal cassette chromosome mec type IVa. In communities with a high prevalence of MRSA, empiric therapy of severe CAP during periods of high influenza activity should include consideration for MRSA.