Lauri Thrupp

Antimicrobial resistance in long-term-care facilities

During the last quarter century, numerous reports have indicated that antimicrobial resistance commonly is encountered in long-term-care facilities (LTCFs). Gram-negative uropathogens resistant to penicillin, cephalosporin, aminoglycoside, or fluoroquinolone antibiotics and methicillin-resistant Staphylococcus aureus have received the greatest attention, but other reports have described the occurrence of multiply-resistant strains of Haemophilus influenzae and vancomycin-resistant enterococci (VRE) in this setting. Antimicrobial-resistant bacteria may enter LTCFs with colonized patients transferred from the hospital, or they may arise in the facility as a result of mutation or gene transfer. Once present, resistant strains tend to persist and become endemic. Rapid dissemination also has been documented in some facilities. Person-to-person transmission via the hands of healthcare workers appears to be the most important means of spread. The LTCF patients most commonly affected are those with serious underlying disease, poor functional status, wounds such as pressure sores, invasive devices such as urinary catheters, and prior antimicrobial therapy. The presence of antimicrobial-resistant pathogens in LTCFs has serious consequences not only for residents but also for LTCFs and hospitals. Experience with control strategies for antimicrobial-resistant pathogens in LTCFs is limited; however, strategies used in hospitals often are inapplicable. Six recommendations for controlling antimicrobial resistance in LTCFs are offered, and four priorities for future research are identified.

Voluntary to Mandatory: Evolution of Strategies and Attitudes toward Influenza Vaccination of Healthcare Personnel

BACKGROUND Assessing the relative success of serial strategies for increasing healthcare personnel (HCP) influenza vaccination rates is important to guide hospital policies to increase vaccine uptake. OBJECTIVE To evaluate serial campaigns that include a mandatory HCP vaccination policy and to describe HCP attitudes toward vaccination and reasons for declination. DESIGN Retrospective cohort study. METHODS We assessed the impact of serial vaccination campaigns on the proportions of HCP who received influenza vaccination during the 2006-2011 influenza seasons. In addition, declination data over these 5 seasons and a 2007 survey of HCP attitudes toward vaccination were collected. RESULTS HCP influenza vaccination rates increased from 44.0% (2,863 of 6,510 HCP) to 62.9% (4,037 of 6,414 HCP) after institution of mobile carts, mandatory declination, and peer-to-peer vaccination efforts. Despite maximal attempts to improve accessibility and convenience, 27.2% (66 of 243) of the surveyed HCP were unwilling to wait more than 10 minutes for a free influenza vaccination, and 23.3% (55 of 236) would be indifferent if they were unable to be vaccinated. In this context, institution of a mandatory vaccination campaign requiring unvaccinated HCP to mask during the influenza season increased rates of compliance to over 90% and markedly reduced the proportion of HCP who declined vaccination as a result of preference. CONCLUSIONS A mandatory influenza vaccination program for HCP was essential to achieving high vaccination rates, despite years of intensive vaccination campaigns focused on increasing accessibility and convenience. Mandatory vaccination policies appear to successfully capture a large portion of HCP who are not opposed to receipt of the vaccine but who have not made vaccination a priority.

Nosocomial Infection and Antibiotic Utilization in Geriatric Patients: A Pilot Prospective Surveillance Program in Skilled Nursing Facilities

Prospective surveillance of nosocomial infection was conducted at seven skilled proprietary nursing facilities in Orange County, Calif., USA. The average incidence of facility-acquired infection was 5.2 infections/1,000 patient days. The most common source of infection was urinary tract (47%), followed by respiratory tract (26%) and skin (14%). The four most common pathogens isolated were Proteus spp. (20%), Escherichia coli (17%), Staphylococcus aureus (13%) and Pseudomonas spp. (11%). Trimethoprim-sulfamethoxazole (20%) was the most frequently used antibiotic among all prescriptions, followed by ampicillin (16%) and ciprofloxacin (14%). Among all residents surveyed, 33% received at least one course of antibiotics during the study. Of special significance was the fact that 4 (22%) of the 18 strains of Pseudomonas were gentamicin resistant as were 12 of 80 (15%) of the strains of Enterobacteriaceae. Furthermore, 9 of 29 (31%) strains of Pseudomonas tested were found resistant to norfloxacin as were 15 of 129 (12%) strains of enterobacteriaceae. Susceptibility patterns of the isolated pathogens were similar to those of the acute care hospital. This study indicates that infection continues to be a major problem in the skilled nursing facility and that antibiotic-resistant pathogens will be a challenge for the future.

Surveillance of colonization and infection with Staphylococcus aureus susceptible or resistant to methicillin in a community skilled-nursing facility.

BACKGROUND Methicillin-resistant Staphylococcus aureus (MRSA) is an important nosocomial pathogen in acute care hospitals and long-term care facilities. Few studies have been reported in private skilled nursing facilities (SNFs) not experiencing outbreaks of infections caused by MRSA. METHODS From a 149-bed SNF with no outbreaks, we report a 1-year prospective surveillance study of S. aureus colonization and infection, with focus on S. aureus phenotypes, both methicillin susceptible (MS) and methicillin resistant (MR). Nasal and stool or rectal screening cultures were done on admission, and all patients underwent screening on at least a quarterly basis for 1 year. RESULTS Overall, 35% of patients were colonized at least once with S. aureus, (72% MS, 25% MR, and 3% mixed phenotypes), 94% of the MRSA were ciprofloxacin resistant. Nasal colonization with any S. aureus was more frequent, but 13% of patients had positive results only in rectal specimens. Twenty-one percent of the newly admitted and 15% of continuing patients acquired colonization during their stay in the SNE Colonization was transient or persistent, persisted longer in the nares compared with colonization in rectal specimens, and was more stable for methicillin-susceptible S. aureus. Nine percent of patients had development of infection with S. aureus. There was no indication that MRSA colonization led to more infections than methicillin-susceptible S. aureus. Of the 13 infected patients in whom cultures had previously been obtained, seven (54%) had been colonized by the same phenotype strains. CONCLUSIONS In this private SNF, endemic S. aureus infections occur at a low frequency, reflecting a moderate level of colonization with S. aureus. However, a trend showing gradual increases in frequencies of colonization and infection is of concern and suggests that in this SNF, future intervention could become warranted.

Tuberculosis prevention and control in long-term-care facilities for older adults.

In the United States, older adults comprise 22% of cases of tuberculous disease but only 12% of the population. Most cases of tuberculosis (TB) occur in community dwellers, but attack rates are highest among frail residents of long-term-care facilities. The detection and treatment of latent TB infection and TB disease can pose special challenges in older adults. Rapid recognition of possible disease, diagnosis, and implementation of airborne precautions are essential to prevent spread. It is the intent of this evidence-based guideline to assist healthcare providers in the prevention and control of TB, specifically in skilled nursing facilities for the elderly.

Antibacterial activity of citrate and acetate

OBJECTIVE We evaluated citrate salt, acetate salt, and their combinations for antibacterial activity against a sample of common pathogens. METHODS Bacterial suspensions were added to serial microdilutions of the salts in broth, with final cell concentrations of 10(4-5) colony-forming units per milliliter. After overnight incubation at 35 degrees C, the minimum inhibitory concentration was recorded. Bactericidal activity was screened by quantitative subcultures from the minimum inhibitory concentration dilution. RESULTS Citrate salt was active against gram-positive species and Candida albicans but showed little activity against gram-negative species; acetate salt showed the opposite results. Their combination did not show synergism or antagonism. CONCLUSION It may be feasible to take advantage of the different antibacterial spectra of these two agents and combine them for possible application such as food or medical preservative agents.

Colonization by Staphylococcus species resistant to methicillin or quinolone on hands of medical personnel in a skilled-nursing facility

We report here a pilot survey of colonization with methicillin- and/or ciprofloxacin-resistant Staphylococcus species on hands of nursing personnel in a private skilled-nursing facility. We found only one nurses aide who carried methicillin-resistant Staphylococcus aureus and one who carried ciprofloxacin-resistant S. aureus, each on only one of the surveys. None of the control nonmedical personnel were found to carry methicillin-resistant S. aureus or ciprofloxacin-resistant S. aureus. The colonization rate of methicillin-resistant coagulase-negative staphylococci on the hands of medical personnel was 59%, compared with 13% for the nonmedical personnel, and the counts of methicillin-resistant coagulase-negative staphylococci were also significantly higher for nursing personnel. For ciprofloxacin-resistant coagulase-negative staphylococci, 30% of nursing personnel had positive cultures whereas no ciprofloxacin-resistant coagulase-negative staphylococci strains were recovered from the nonmedical control cohort. Three of the patients had presumptive infections with methicillin- or ciprofloxacin-resistant coagulase-negative staphylococci, all urinary tract infections. Personnel hands represent a likely mode of transmission of such strains between patients, and skilled-nursing facility patients may represent a reservoir for carrying the coagulase-negative staphylococci back to acute care facilities.

Bactericidal activity of citrate against Gram-positive cocci

Aims: Coagulase‐negative staphylococci (CNS) are now important nosocomial pathogens and are usually resistant to multiple antibiotics. Citrate is an alternative antimicrobial product which has been used as a preservative.

High Nasal Burden of Methicillin-Resistant Staphylococcus aureus Increases Risk of Invasive Disease

ABSTRACT In a retrospective cohort study of 1,140 patients harboring methicillin-resistant Staphylococcus aureus, the nasal burden was low in 31%, category 1+ to 2+ in 54%, and category 3+ to 4+ in 15%. There was a significant trend in infection risk with increasing nasal burden (P = 0.007). In multivariate models, high nasal burden remained significantly associated with invasive infection.

Infection surveillance and antibiotic utilization in a community-based skilled nursing facility

To survey the types of suspect infections, the antibiotic utilization and the patterns of antibiotic resistance among bacterial pathogens in a community Skilled Nursing Facility (SNF), we conducted a 20-month prospective observational surveillance program comprising all 585 patients admitted to a 149-bed private community SNF. Data were collected from medical charts, laboratory reports and nurses reports. Overall, 41% of the patients developed at least one presumptive nosocomial infection, and 54% of the patients received one or more antibiotic treatments. The overall presumptive nosocomial infection rate was 7.2 per 1000 patient days. The most common sites of presumptive nosocomial infection were the urinary tract (38%) and the respiratory tract (28%). The most common pathogens overall were E. coli (25%). Antibiotic groups used most frequently were the quinolones (22% of prescriptions). Thirty-nine percent of the Staphylococcus aureus isolates associated with suspected infections were resistant to methicillin, and of these 94% were also resistant to ciprofloxacin. Most of the resistant S. aureus isolates were from indwelling catheter-associated with UTIs. Infections associated with quinolone resistant strains of gramnegative bacilli were infrequent. No epidemiologic evidence of nosocomial clustering was apparent.