Impact of surgical training on incidence of surgical site infection

BACKGROUND: Despite availability of other training forms, tutorial assistance cannot be entirely replaced in surgical education. Concerns exist that tutorial assistance may lead to an increased rate of surgical site infection (SSI). The purpose of the present study was to investigate whether the risk of SSI is higher after surgery with tutorial assistance than after surgery performed autonomously by a fully trained surgeon. METHODS: All consecutive visceral, vascular, and traumatological inpatient procedures at a Swiss University Hospital were prospectively recorded during a 24-month period, and the patients were followed for 12 months to ascertain the occurrence of SSI. Using univariable and multivariable logistic regressions, we assessed the association of tutorial assistance surgery with SSI in 6,103 interventions. RESULTS: Autonomously performed surgery was associated with SSI in univariable analysis (5.36% SSI vs. 3.81% for tutorial assistance, p = 0.006). In multivariable analysis, the odds of SSI for tutorial assistance was no longer significantly lower (Odds Ratio [OR] = 0.82; 95% Confidence Interval [CI]: 0.62-1.09; p = 0.163). CONCLUSIONS: Surgical training does not lead to higher SSI rate if trainees are adequately supervised and interventions are carefully selected. Although other forms of training are useful, tutorial assistance in the operating room continues to be the mainstay of surgical education.

Infection with human herpesvirus 8 and transplant-associated gammopathy

BACKGROUND: The role of human herpesvirus (HHV)-8 in the pathogenesis of multiple myeloma and its pre-malignant state of monoclonal gammopathy is unclear. HHV-8 is transmitted by organ transplantation, representing a unique model with which to investigate primary HHV-8 infection. METHODS: The authors studied the incidence of clonal gammopathy in renal transplant recipients and correlated it with previous and recent HHV-8 infection. RESULTS: Clonal gammopathy was observed in 31 of 162 (19%) HHV-8-seronegative patients, in 5 of 17 (29%) HHV-8-seropositive patients, and in 9 of 24 (38%) HHV-8 seroconverters within 5 years after transplantation. Gammopathy was often transient, and no progression to myeloma was observed. Two patients with persistent gammopathy developed B-cell lymphoma. In a logistic regression model, HHV-8 serostatus of the graft recipient was significantly associated with subsequent development of gammopathy, with a relative risk (RR) of 1.9 and a 95% confidence interval (CI) of 0.5 to 6.4 for an HHV-8-seropositive recipient and an RR of 2.9 and a 95% CI of 1.01 to 8.0 for seroconverters as compared with baseline (HHV-8 seronegative). Other significant variables were cytomegalovirus (CMV) serostatus and the intensity of immunosuppression (RR of 10.4 and 95% CI of 2.6-41.7 for a CMV-negative recipient with a CMV-positive donor vs. a CMV-negative recipient with a CMV-negative donor and RR of 17.6 and 95% CI of 2.0-150.8 if OKT3 was used vs. no use of antilymphocytic substances). CONCLUSIONS: Transplant recipients with HHV-8 infection are more likely to develop clonal gammopathy. However, this risk is much lower than the risk conferred by CMV infection and antilymphocytic therapy, arguing against a major role of HHV-8 infection in the pathogenesis of clonal plasma cell proliferation.

The kinetics of feline leukaemia virus shedding in experimentally infected cats are associated with infection outcome

Feline leukaemia virus (FeLV) infection in felids results mainly from oronasal exposure to infectious saliva and nasal secretions, but the potential for viral transmission through faeces and urine has not been completely characterized. In order to assess and compare potential FeLV transmission routes, we determined the viral kinetics in plasma, saliva, faeces and urine during early experimental FeLV infection (up to week 15 post-exposure) in specific pathogen-free cats. In addition to monitoring p27 antigen levels measured by ELISA, we evaluated the presence of infectious particles by cell culture assays and quantified viral RNA loads by a quantitative real-time TaqMan polymerase chain reaction. RNA load was associated with infection outcome (high load-progressive infection; low load-regressive infection) not only in plasma, but also in saliva, faeces and urine. Infectious virus was isolated from the saliva, faeces and urine of infected cats with progressive infection as early as 3-6 weeks post-infection, but usually not in cats with regressive infection. In cats with progressive infection, therefore, not only saliva but also faeces and to some extent urine might represent potential FeLV transmission routes. These results should be taken into account when modelling FeLV-host interactions and assessing FeLV transmission risk. Moreover, during early FeLV infection, detection of viral RNA in saliva may be used as an indicator of recent virus exposure, even in cats without detectable antigenaemia/viraemia. To determine the clinically relevant outcome of FeLV infection in exposed cats, however, p27 antigen levels in the peripheral blood should be measured.

Risk scoring for setting priorities in a monitoring of antimicrobial resistance in meat and meat products

Meat and meat products can be contaminated with different species of bacteria resistant to various antimicrobials. The human health risk of a type of meat or meat product carry by emerging antimicrobial resistance depends on (i) the prevalence of contamination with resistant bacteria, (ii) the human health consequences of an infection with a specific bacterium resistant to a specific antimicrobial and (iii) the consumption volume of a specific product. The objective of this study was to compare the risk for consumers arising from their exposure to antibiotic resistant bacteria from meat of four different types (chicken, pork, beef and veal), distributed in four different product categories (fresh meat, frozen meat, dried raw meat products and heat-treated meat products). A semi-quantitative risk assessment model, evaluating each food chain step, was built in order to get an estimated score for the prevalence of Campylobacter spp., Enterococcus spp. and Escherichia coli in each product category. To assess human health impact, nine combinations of bacterial species and antimicrobial agents were considered based on a published risk profile. The combination of the prevalence at retail, the human health impact and the amount of meat or product consumed, provided the relative proportion of total risk attributed to each category of product, resulting in a high, medium or low human health risk. According to the results of the model, chicken (mostly fresh and frozen meat) contributed 6.7% of the overall risk in the highest category and pork (mostly fresh meat and dried raw meat products) contributed 4.0%. The contribution of beef and veal was of 0.4% and 0.1% respectively. The results were tested and discussed for single parameter changes of the model. This risk assessment was a useful tool for targeting antimicrobial resistance monitoring to those meat product categories where the expected risk for public health was greater.

Diseases in neonatal foals. Part 2: potential risk factors for a higher incidence of infectious diseases during the first 30 days post partum

REASON FOR PERFORMING STUDY: The development of clinical illness in foals is usually predetermined by perinatal history, management or stressful environmental conditions. OBJECTIVES: To determine potential risk factors for an increased incidence of infectious diseases during the first 30 days post partum. METHODS: The population consisted of Thoroughbred foals born on stud farms in the Newmarket (UK) area in 2005 (n = 1031). They were followed for their first 30 days. Factors suspected to influence the incidence of infectious neonatal diseases were examined in a logistic regression approach for each of the 3 outcomes (total infectious diseases, systemic disease with diarrhoea and total infectious diseases excluding diarrhoea). All 28 factors were either foal or mare or stud farm related. RESULTS: Several significant risk factors for a higher disease incidence, such as birth complications, colostrum intake by stomach tube and leucocytosis 12-48 h post partum were identified. The factor 'boarding stud' seemed to be protective against disease. CONCLUSION: Some factors, such as the mare's time at stud before foaling, the mare's rotavirus vaccination schedule and fibrinogen-values that empirically had been linked to the outcome previously were not confirmed as relevant. This included the reported useful prophylactic treatment with antimicrobial drugs. POTENTIAL RELEVANCE: Factors to be considered when evaluating newborn foals include: stud management, the birth process, route of colostrum intake, white and red blood cells, and the date of birth. These may help to detect foals at risk to develop an infection so that targeted prophylactic measures can be initiated.

Prevalence and risk-factor analysis of Shiga toxigenic Escherichia coli in faecal samples of organically and conventionally farmed dairy cattle

Cattle are a natural reservoir for Shiga toxigenic Escherichia coli (STEC), however, no data are available on the prevalence and their possible association with organic or conventional farming practices. We have therefore studied the prevalence of STEC and specifically O157:H7 in Swiss dairy cattle by collecting faeces from approximately 500 cows from 60 farms with organic production (OP) and 60 farms with integrated (conventional) production (IP). IP farms were matched to OP farms and were comparable in terms of community, agricultural zone, and number of cows per farm. E. coli were grown overnight in an enrichment medium, followed by DNA isolation and PCR analysis using specific TaqMan assays. STEC were detected in all farms and O157:H7 were present in 25% of OP farms and 17% of IP farms. STEC were detected in 58% and O157:H7 were evidenced in 4.6% of individual faeces. Multivariate statistical analyses of over 250 parameters revealed several risk-factors for the presence of STEC and O157:H7. Risk-factors were mainly related to the potential of cross-contamination of feeds and cross-infection of cows, and age of the animals. In general, no significant differences between the two farm types concerning prevalence or risk for carrying STEC or O157:H7 were observed. Because the incidence of human disease caused by STEC in Switzerland is low, the risk that people to get infected appears to be small despite a relatively high prevalence in cattle. Nevertheless, control and prevention practices are indicated to avoid contamination of animal products.

Influence of deep sternal wound infection on long-term survival after cardiac surgery

BACKGROUND: This study aimed to investigate the influence of deep sternal wound infection on long-term survival following cardiac surgery. MATERIAL AND METHODS: In our institutional database we retrospectively evaluated medical records of 4732 adult patients who received open-heart surgery from January 1995 through December 2005. The predictive factors for DSWI were determined using logistic regression analysis. Then, each patient with deep sternal wound infection (DSWI) was matched with 2 controls without DSWI, according to the risk factors identified previously. After checking balance resulting from matching, short-term mortality was compared between groups using a paired test, and long-term survival was compared using Kaplan-Meier analysis and a Cox proportional hazard model. RESULTS: Overall, 4732 records were analyzed. The mean age of the investigated population was 69.3±12.8 years. DSWI occurred in 74 (1.56%) patients. Significant independent predictive factors for deep sternal infections were active smoking (OR 2.19, CI95 1.35-3.53, p=0.001), obesity (OR 1.96, CI95 1.20-3.21, p=0.007), and insulin-dependent diabetes mellitus (OR 2.09, CI95 1.05-10.06, p=0.016). Mean follow-up in the matched set was 125 months, IQR 99-162. After matching, in-hospital mortality was higher in the DSWI group (8.1% vs. 2.7% p=0.03), but DSWI was not an independent predictor of long-term survival (adjusted HR 1.5, CI95 0.7-3.2, p=0.33). CONCLUSIONS: The results presented in this report clearly show that post-sternotomy deep wound infection does not influence long-term survival in an adult general cardio-surgical patient population.

Evaluation of pet contact as a risk factor for carriage of multidrug-resistant staphylococci in nursing home residents

BACKGROUND Pets, often used as companionship and for psychological support in the therapy of nursing home residents, have been implicated as reservoirs for antibiotic-resistant bacteria. We investigated the importance of pets as reservoirs of multidrug-resistant (MDR) staphylococci in nursing homes. METHODS We assessed the carriage of MDR staphylococci in pets and in 2 groups of residents, those living in nursing homes with pets and those living without pet contacts. We collected demographic, health status, and human-pet contact data by means of questionnaires. We assessed potential bacteria transmission pathways by investigating physical resident-to-pet contact. RESULTS The observed prevalence of MDR staphylococci carriage was 84/229 (37%) in residents living with pets and 99/216 (46%) in those not living with pets (adjusted odds ratio [aOR], 0.6; 95% confidence interval [CI], 0.4-0.9). Active pet contact was associated with lower carriage of MDR staphylococci (aOR, 0.5; 95% CI, 0.4-0.8). Antibiotic treatment during the previous 3 months was associated with significantly increased risk for MDR carriage in residents (aOR, 3.1; 95% CI, 1.8-5.7). CONCLUSIONS We found no evidence that the previously reported benefits of pet contact are compromised by the increased risk of carriage of MDR staphylococci in residents associated with interaction with these animals in nursing homes. Thus, contact with pets, always under good hygiene standards, should be encouraged in these settings.

Risk Assessment of the Introduction of Porcine Reproductive and Respiratory Syndrome Virus via Boar Semen into Switzerland as an Example of a PRRSV-Free Country

Switzerland is currently porcine reproductive and respiratory syndrome virus (PRRSV) free, but semen imports from PRRSV-infected European countries are increasing. As the virus can be transmitted via semen, for example, when a free boar stud becomes infected, and the risk of its import in terms of PRRSV introduction is unknown, the annual probability to accidentally import the virus into Switzerland was estimated in a risk assessment. A quantitative stochastic model was set up with data comprised by import figures of 2010, interviews with boar stud owners and expert opinion. It resulted in an annual median number of 0.18 imported ejaculates (= imported semen doses from one collection from one donor) from PRRSV-infected boars. Hence, one infected ejaculate would be imported every 6 years and infect a mean of 10 sows. These results suggest that under current circumstances, there is a substantial risk of PRRSV introduction into Switzerland via imported boar semen and that measures to enhance safety of imports should be taken. The time from infection of a previously negative boar stud to its detection had the highest impact on the number of imported 'positive' ejaculates. Therefore, emphasis should be placed on PRRSV monitoring protocols in boar studs. Results indicated that a substantial increase in safety could only be achieved with much tighter sampling protocols than currently performed. Generally, the model could easily be customized for other applications like other countries or regions or even sow farms that want to estimate their risk when purchasing semen from a particular boar stud.

Circumcision and HIV infection among men who have sex with men in Britain: the insertive sexual role

The objective was to examine the association between circumcision status and self-reported HIV infection among men who have sex with men (MSM) in Britain who predominantly or exclusively engaged in insertive anal intercourse. In 2007-2008, a convenience sample of MSM living in Britain was recruited through websites, in sexual health clinics, bars, clubs, and other venues. Men completed an online survey which included questions on circumcision status, HIV testing, HIV status, sexual risk behavior, and sexual role for anal sex. The analysis was restricted to 1,521 white British MSM who reported unprotected anal intercourse in the previous 3 months and who said they only or mostly took the insertive role during anal sex. Of these men, 254 (16.7 %) were circumcised. Among men who had had a previous HIV test (n = 1,097), self-reported HIV seropositivity was 8.6 % for circumcised men (17/197) and 8.9 % for uncircumcised men (80/900) (unadjusted odds ratio [OR], 0.97; 95 % confidence interval [95 % CI], 0.56, 1.67). In a multivariable logistic model adjusted for known risk factors for HIV infection, there was no evidence of an association between HIV seropositivity and circumcision status (adjusted OR, 0.79; 95 % CI, 0.43, 1.44), even among the 400 MSM who engaged exclusively in insertive anal sex (adjusted OR, 0.84; 95 % CI, 0.25, 2.81). Our study provides further evidence that circumcision is unlikely to be an effective strategy for HIV prevention among MSM in Britain.

Francisella tularensis infection in a stone marten (Martes foina) without classic pathological lesions consistent with tularemia.

The current report describes the isolation and typing of a strain of Francisella tularensis, the causative agent of tularemia, from the spleen of a stone marten (Martes foina) showing no classic lesions consistent with the disease. The identification of this bacterium, belonging to the World Health Organization risk 3 category and considered to have a low infectious dose, could be performed only because of an ongoing project screening F. tularensis in the environment sensu lato. The findings described herein should alert diagnostic laboratories of the possible presence of F. tularensis in clinical samples in countries where tularemia is endemic even in cases with no consistent anamnesis and from unsuspected animal species.

Risk Factors and Outcomes for Late Presentation for HIV-Positive Persons in Europe: Results from the Collaboration of Observational HIV Epidemiological Research Europe Study (COHERE)

Background Few studies have monitored late presentation (LP) of HIV infection over the European continent, including Eastern Europe. Study objectives were to explore the impact of LP on AIDS and mortality. Methods and Findings LP was defined in Collaboration of Observational HIV Epidemiological Research Europe (COHERE) as HIV diagnosis with a CD4 count <350/mm3 or an AIDS diagnosis within 6 months of HIV diagnosis among persons presenting for care between 1 January 2000 and 30 June 2011. Logistic regression was used to identify factors associated with LP and Poisson regression to explore the impact on AIDS/death. 84,524 individuals from 23 cohorts in 35 countries contributed data; 45,488 were LP (53.8%). LP was highest in heterosexual males (66.1%), Southern European countries (57.0%), and persons originating from Africa (65.1%). LP decreased from 57.3% in 2000 to 51.7% in 2010/2011 (adjusted odds ratio [aOR] 0.96; 95% CI 0.95–0.97). LP decreased over time in both Central and Northern Europe among homosexual men, and male and female heterosexuals, but increased over time for female heterosexuals and male intravenous drug users (IDUs) from Southern Europe and in male and female IDUs from Eastern Europe. 8,187 AIDS/deaths occurred during 327,003 person-years of follow-up. In the first year after HIV diagnosis, LP was associated with over a 13-fold increased incidence of AIDS/death in Southern Europe (adjusted incidence rate ratio [aIRR] 13.02; 95% CI 8.19–20.70) and over a 6-fold increased rate in Eastern Europe (aIRR 6.64; 95% CI 3.55–12.43). Conclusions LP has decreased over time across Europe, but remains a significant issue in the region in all HIV exposure groups. LP increased in male IDUs and female heterosexuals from Southern Europe and IDUs in Eastern Europe. LP was associated with an increased rate of AIDS/deaths, particularly in the first year after HIV diagnosis, with significant variation across Europe. Earlier and more widespread testing, timely referrals after testing positive, and improved retention in care strategies are required to further reduce the incidence of LP.

Risk of tuberculosis following HIV seroconversion in high-income countries

Background Few data exist on tuberculosis (TB) incidence according to time from HIV seroconversion in high-income countries and whether rates following initiation of a combination of antiretroviral treatments (cARTs) differ from those soon after seroconversion. Methods Data on individuals with well estimated dates of HIV seroconversion were used to analyse post-seroconversion TB rates, ending at the earliest of 1 January 1997, death or last clinic visit. TB rates were also estimated following cART initiation, ending at the earliest of death or last clinic visit. Poisson models were used to examine the effect of current and past level of immunosuppression on TB risk after cART initiation. Results Of 19 815 individuals at risk during 1982–1996, TB incidence increased from 5.89/1000 person-years (PY) (95% CI 3.77 to 8.76) in the first year after seroconversion to 10.56 (4.83 to 20.04, p=0.01) at 10 years. Among 11 178 TB-free individuals initiating cART, the TB rate in the first year after cART initiation was 4.23/1000 PY (3.07 to 5.71) and dropped thereafter, remaining constant from year 2 onwards averaging at 1.64/1000 PY (1.29 to 2.05). Current CD4 count was inversely associated with TB rates, while nadir CD4 count was not associated with TB rates after adjustment for current CD4 count, HIV-RNA at cART initiation. Conclusions TB risk increases with duration of HIV infection in the absence of cART. Following cART initiation, TB incidence rates were lower than levels immediately following seroconversion. Implementation of current recommendations to prevent TB in early HIV infection could be beneficial.

High proportion of healthcare-associated urinary tract infection in the absence of prior exposure to urinary catheter: a cross-sectional study

Exposure to urinary catheters is considered the most important risk factor for healthcare-associated urinary tract infection (UTI) and is associated with significant morbidity and substantial extra-costs. In this study, we assessed the impact of urinary catheterisation (UC) on symptomatic healthcare-associated UTI among hospitalized patients.

Risk factors for anal cancer in persons infected with HIV: a nested case-control study in the Swiss HIV Cohort Study

Although persons infected with human immunodeficiency virus (HIV), particularly men who have sex with men, are at excess risk for anal cancer, it has been difficult to disentangle the influences of anal exposure to human papillomavirus (HPV) infection, immunodeficiency, and combined antiretroviral therapy. A case-control study that included 59 anal cancer cases and 295 individually matched controls was nested in the Swiss HIV Cohort Study (1988-2011). In a subset of 41 cases and 114 controls, HPV antibodies were tested. A majority of anal cancer cases (73%) were men who have sex with men. Current smoking was significantly associated with anal cancer (odds ratio (OR) = 2.59, 95% confidence interval (CI): 1.25, 5.34), as were antibodies against L1 (OR = 4.52, 95% CI: 2.00, 10.20) and E6 (OR = ∞, 95% CI: 4.64, ∞) of HPV16, as well as low CD4+ cell counts, whether measured at nadir (OR per 100-cell/μL decrease = 1.53, 95% CI: 1.18, 2.00) or at cancer diagnosis (OR per 100-cell/μL decrease = 1.24, 95% CI: 1.08, 1.42). However, the influence of CD4+ cell counts appeared to be strongest 6-7 years prior to anal cancer diagnosis (OR for <200 vs. ≥500 cells/μL = 14.0, 95% CI: 3.85, 50.9). Smoking cessation and avoidance of even moderate levels of immunosuppression appear to be important in reducing long-term anal cancer risks.