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OBJECTIVES: To compare routine glove use by healthcare workers for all residents, without use of contact-isolation precautions, with contact-isolation precautions for the care of residents who had vancomycin-resistant enterococci or methicillin-resistant Staphylococcus aureus isolated from a clinical culture. DESIGN: Random allocation of two similar sections of the skilled-care unit to one of the infection-control strategies during an 18-month study period. SETTING: Skilled-care unit of a 667-bed acute- and long-term care facility. PARTICIPANTS: All residents present or admitted to the skilled-care unit from June 1, 1998, through December 7, 1999. MEASUREMENTS: Resident acquisition of four antimicrobial-resistant organisms (methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, or extended-spectrum beta-lactamase-producing Klebsiella pneumoniae or Escherichia coli). All isolates were strain typed. The facility level costs associated with each strategy were estimated. RESULTS: Resident acquisition of antimicrobial-resistant organisms was no different in the glove-use and isolation-precautions sections (31 episodes (1.5 per 1,000 resident-days) vs 38 episodes (1.6 per 1,000 resident-days)). Acquisition of either of two prevalent K. pneumoniae strains was more likely (P=.06) in residents in the isolation-precautions section. The estimated costs of contact-isolation precautions were 40% greater than those of routine glove use. CONCLUSION: There was a similar frequency of transmission of antimicrobial-resistant bacteria in the two study sections; there was evidence for resident-to-resident K. pneumoniae transmission in the isolation-precautions section. Routine glove use for healthcare workers, which decreases resident social isolation and healthcare facility costs, may be preferable in many long-term care facilities. [ABSTRACT FROM AUTHOR]

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).

Of the 9 vancomycin-resistant Staphylococcus aureus (VRSA) cases reported to date in the literature, 7 occurred in Michigan. In 5 of the 7 Michigan VRSA cases, an Inc18-like vanA plasmid was identified in the VRSA isolate and/or an associated vancomycin-resistant Enterococcus (VRE) isolate from the same patient. This plasmid may play a critical role in the emergence of VRSA. We studied the geographical distribution of the plasmid by testing 1,641 VRE isolates from three separate collections by PCR for plasmid-specific genes traA, repR, and vanA. Isolates from one collection (phase 2) were recovered from surveillance cultures collected in 17 hospitals in 13 states. All VRE isolates from 2 Michigan institutions (n = 386) and between 60 and 70 VRE isolates (n = 883) from the other hospitals were tested. Fifteen VRE isolates (3.9%) from Michigan were positive for an Inc18-like vanA plasmid (9 E. faecalis [12.5%], 3 E. faecium [1.0%], 2 E. avium, and 1 E. raffinosus). Six VRE isolates (0.6%) from outside Michigan were positive (3 E. faecalis [2.7%] and 3 E. faecium [0.4%]). Of all E. faecalis isolates tested, 6.0% were positive for the plasmid, compared to 0.6% for E. faecium and 3.0% for other spp. Fourteen of the 15 plasmid-positive isolates from Michigan had the same Tn1546 insertion site location as the VRSA-associated Inc18-like plasmid, whereas 5 of 6 plasmid-positive isolates from outside Michigan differed in this characteristic. Most plasmid-positive E. faecalis isolates demonstrated diverse patterns by PFGE, with the exception of three pairs with indistinguishable patterns, suggesting that the plasmid is mobile in nature. Although VRE isolates with the VRSA-associated Inc18-like vanA plasmid were more common in Michigan, they remain rare. Periodic surveillance of VRE isolates for the plasmid may be useful in predicting the occurrence of VRSA.

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.

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 and 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.

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 < 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.

We conducted a survey in 2005 of infectious diseases consultants and asked about persistent bacteremia due to methicillin-resistant Staphylococcus aureus. Many consultants perceived an increase in the frequency of illness, and, when presented with vancomycin minimum inhibitory concentrations approaching the limit of the susceptible range, most consultants indicated that they would switch to newer antimicrobial agents for treatment.

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.

Background: The mail-related dispersal of Bacillus anthracis spores in the Washington, D.C., area during October 2001 resulted in 5 confirmed cases of inhalational anthrax. We identified an additional 144 ill persons who were potentially exposed to aerosolized spores and whose symptoms were compatible with early inhalational anthrax but whose clinical course and nonserologic laboratory evaluation revealed no evidence for B. anthracis infection. We hypothesized that early antibiotic use could have decreased the sensitivity of diagnostic tests or that bioterrorism-related inhalational anthrax may include mild disease., Methods: Eligible patients included those with illness compatible with early inhalational anthrax who had potential exposure to B. anthracis. Patient serum samples were tested for immunoglobulin G (IgG) antibody against B. anthracis protective antigen (PA) using a sensitive enzyme-linked immunosorbant assay (sensitivity, 97.6%)., Results: Of the 144 eligible patients, 66 (46%) had convalescent-phase serum samples available for testing; 29 (44%) worked in an area considered to pose a high risk of exposure to B. anthracis spores. Of the 37 patients who worked in areas that did not meet the definition of high-risk exposure, 23 (62%) worked in United States postal or other government facilities in which exposure was plausible but not documented. None of the 66 patients with convalescent-phase serum samples showed evidence of an anti-PA IgG serologic response to B. anthracis., Conclusions: These data suggest that a mild form of inhalational anthrax did not occur and that surveillance for moderate or severe illness was adequate to identify all inhalational anthrax cases resulting from the Washington, D.C., bioterrorism-related anthrax exposures.

This report summarizes findings of a national survey conducted among infectious diseases consultants to assess complications associated with influenza during the 2003-2004 influenza season. The survey identified severe complications, including secondary infection with Staphylococcus aureus and deaths among children and adults, as well as perceived shortages in rapid diagnostic tests and influenza vaccine.

Individuals undergoing hemodialysis may be at increased risk for emerging antimicrobial resistance from vancomycin-intermediate Staphylococcus aureus (VISA) and vancomycin-resistant S. aureus (VRSA). The laboratory detection of VISA and VRSA is challenging and requires the use of well-thought-out algorithms. Newly available antimicrobials such as quinipristin/dalfopristin, linezolid, and daptomycin, as well as older drugs such as trimethoprim-sulfamethoxazole appear to be active against recent strains of VISA and VRSA. Prevention of VISA and VRSA necessitates determining the appropriateness of vancomycin use in renal patients and giving priority to infection control precautions in both inpatient and outpatient settings. Because most VISA and all VRSA to date have arisen from endemic methicillin-resistant S. aureus (MRSA), and in the case of VRSA have acquired genes from vancomycin-resistant enterococci (VRE), the emergence of VISA and VRSA should provide renewed motivation for the containment of MRSA and VRE transmission in the hemodialysis population.

Objective: The National Nosocomial Infections Surveillance (NNIS) System personnel report trends in antimicrobial-resistant pathogens. To validate select antimicrobial susceptibility testing results and to identify test methods that tend to produce errors, we conducted proficiency testing among NNIS System hospital laboratories., Setting: NNIS System hospital laboratories in the United States., Methods: Each laboratory received five organisms (ie, an imipenem-resistant Serratia marcescens, an oxacillin-resistant Staphylococcus aureus, a vancomycin-resistant Enterococcus faecalis, a vancomycin-intermediate Staphylococcus epidermidis, and an extended-spectrum beta-lactamase (ESbetaL)-producing Klebsiella pneumoniae). Testing results were compared with reference testing results from the Centers for Disease Control and Prevention., Results: Of 138 laboratories testing imipenem against the Serratia marcescens strain, 110 (80%) correctly reported minimum inhibitory concentrations (MICs) or zone sizes in the resistant range. All 193 participating laboratories correctly reported the Staphylococcus aureus strain as oxacillin resistant Of the 193 laboratories, 169 (88%) reported correct MICs or zone sizes for the vancomycin-resistant Enterococcus faecalis. One hundred sixty-two (84%) of 193 laboratories demonstrated the ability to detect a vancomycin-intermediate strain of Staphylococcus epidermidis, however, disk diffusion performed poorly when testing both staphylococci and enterococci with vancomycin. Although laboratory personnel correctly reported nonsusceptible extended-spectrum cephalosporins and aztreonam results for K. pneumoniae, only 98 (51%) of 193 correctly reported this organism as an ESbetaL producer., Conclusion: Overall, NNIS System hospital laboratory personnel detected most emerging resistance patterns. Disk diffusion continues to be unreliable for vancomycin testing of staphylococci and must be used cautiously for enterococci. Further education on the processing of ESbetaL-producing organisms is warranted.

In June 2000, vancomycin-intermediate Staphylococcus aureus (VISA) was isolated from a 27-year-old home health-care patient following a complicated cholecystectomy. Two VISA strains were identified with identical MICs to all antimicrobials tested except oxacillin and with closely related pulsed-field gel electrophoresis types. The patient was treated successfully with antimicrobial therapy, biliary drainage, and reconstruction. Standard precautions in the home health setting appear successful in preventing transmission.

In the fall of 1996, fish kills in Maryland rivers were attributed to the dinoflagellate, Pfiesteria piscicida. After a group of researchers established a potential link between exposure to Pfiesteria and an illness causing memory problems, state health authorities closed a portion of the Pocomoke River. To determine the extent of illness, the range of symptoms, potential risk factors for disease, and to provide information to concerned citizens, a toll-free hotline was created. All symptomatic persons who called the toll-free number were administered a standardized questionnaire. Persons who had been exposed to Pfiesteria or Pfiesteria-laden waters were more likely to have respiratory, neurologic, dermatologic, and gastrointestinal problems than those persons without exposure. Among the persons calling the hotline, many had extensive neuropsychologic testing. Of the neuropsychologic test battery, low scores on the Rey Auditory Verbal Learning Test (RAVLT), a standardized measure of learning and memory, best characterized illness related to Pfiesteria exposure. Patients with low RAVLT scores were more likely to have neurologic symptoms and skin lesions than control subjects. Low RAVLT scores were associated with fishing (OR, 9.00, 95% CI, 106, 409.87), catching fish with lesions (OR, 6.17, 95% CI 1.27, 32.10), and handling fish with lesions (OR, 5.34, 95% CI, 1.05, 29.92), but not with consumption of seafood. While preliminary, these results do suggest that some risk factors for Pfiesteria-related illness may be easy to modify and used to prevent unnecessary human exposure.