Circulating genotypes of Leptospira in French Polynesia : An 9-year molecular epidemiology surveillance follow-up study.

BACKGROUND: Leptospirosis is a widespread zoonosis with global impact, particularly among vulnerable populations in resource-poor settings in tropical countries. Rodents have been considered to be the main reservoir of the disease; however, a wide variety of mammals can act as hosts as well. Here we examine the genetic diversity of Leptospira strains from biological samples of patients and animals in French Polynesia (FP) from 2011 to 2019. METHODOLOGY/PRINCIPAL FINDINGS: From 2011 to 2019, we have collected 444 blood samples from patients diagnosed as having leptospirosis. The limited volume of clinical material and low amount of leptospiral DNA in blood samples led us to develop a nested PCR targeting the secY locus that enabled us to amplify and sequence 244 samples (55%). In addition, 20 Leptospira strains recovered from the blood of patients from 2002 to 2011 were sequenced and fully characterized at the serogroup level and used as reference strains for the association of different phylogenetic branches with respective serogroups. The secY sequences were compared with publicly available sequences from patients and animal reservoirs in FP (n = 79). We identified rats as the main source of infection for L. borgpetersenii serogroup Ballum and L. interrogans serogroup Icterohaemorrhagiae, dogs as the main source of infection for L. interrogans serogroup Australis, and farm pigs as the main source of infection for L. interrogans serogroups Pomona or Canicola. L. interrogans was associated with the most severe infections with 10 and 5 fatal cases due to serogroups Icterohaemorrhagiae and Australis, respectively. Mortality was significantly associated with older age (p-value < 0.001). CONCLUSIONS/SIGNIFICANCE: We described the population dynamics of leptospires circulating among patients in FP, including two patients who were reinfected with unrelated Leptospira genotypes, and clarified the local role of the animal reservoirs in the transmission route of leptospirosis to humans. Routine Leptospira genotyping directly on biological samples should allow the epidemiological follow-up of circulating strains and assess the impact of control interventions on disease transmission.

Dengue virus serotype 2 (DENV-2) outbreak, French Polynesia, 2019.

In 1996-97, the last dengue virus serotype 2 (DENV-2) outbreak occurred in French Polynesia. In February 2019, DENV-2 infection was detected in a traveller from New Caledonia. In March, autochthonous DENV-2 infection was diagnosed in two residents. A DENV-2 outbreak was declared on 10 April with 106 cases as at 24 June. Most of the population is not immune to DENV-2; a large epidemic could occur with risk of imported cases in mainland France.

Zika Virus Infection during Pregnancy and Effects on Early Childhood Development, French Polynesia, 2013-2016.

Congenital Zika virus syndrome consists of a large spectrum of neurologic abnormalities seen in infants infected with Zika virus in utero. However, little is known about the effects of Zika virus intrauterine infection on the neurocognitive development of children born without birth defects. Using a case-control study design, we investigated the temporal association of a cluster of congenital defects with Zika virus infection. In a nested study, we also assessed the early childhood development of children recruited in the initial study as controls who were born without known birth defects,. We found evidence for an association of congenital defects with both maternal Zika virus seropositivity (time of infection unknown) and symptomatic Zika virus infection during pregnancy. Although the early childhood development assessment found no excess burden of developmental delay associated with maternal Zika virus infection, larger, longer-term studies are needed.

Use of surveillance data to calculate the sample size and the statistical power of randomized clinical trials testing Staphylococcus aureus vaccine efficacy in orthopedic surgery.

BACKGROUND: Patients undergoing primary total hip arthroplasty (THA) would be a worthy population for anti-staphylococcal vaccines. The objective is to assess sample size for significant vaccine efficacy (VE) in a randomized clinical trial (RCT). METHODS: Data from a surveillance network of surgical site infection in France between 2008 and 2011 were used. The outcome was S. aureus SSI (SASSI) within 30 days after surgery. Statistical power was estimated by simulations repeated for theoretical VE ranging from 20% to 100% and for sample sizes from 250 to 8000 individuals per arm. RESULTS: 18,688 patients undergoing THA were included; 66 (0.35%) SASSI occurred. For a 1% SASSI rate, the sample size would be at least 1316 patients per arm to detect significant VE of 80% with 80% power. CONCLUSION: Simulations with real-life data from surveillance of hospital acquired infections allow estimation of power for RCT and sample size to reach the required power.

High risk of dengue type 2 outbreak in French Polynesia, 2017.

In French Polynesia, the four serotypes of dengue virus (DENV-1 to -4) have caused 14 epidemics since the mid-1940s. From the end of 2016, an increasing number of Pacific Island Countries and Territories have reported DENV-2 outbreaks and in February 2017, DENV-2 infection was detected in French Polynesia in three travellers from Vanuatu. As DENV-2 has not been circulating in French Polynesia since December 2000, there is high risk for an outbreak to occur.

Compliance with standard precautions: Results of a French national audit.

BACKGROUND: Standard precautions (SPs) aim to reduce the risk of cross-transmission of microorganisms. The objectives of the present study were to assess institutional policies for SPs promotion, available resources for SPs implementation, and education of health care workers (HCWs) and their compliance with SPs. METHODS: A multisite mixed-methods audit was conducted in 2011. Self-assessment questionnaires were administered at institution, ward, and HCW levels in French health care facilities (HCFs). Results were given as percentage of objectives achieved (POA) or percentage of "never or sometimes," "often," and "always" responses for each question. RESULTS: A total of 1599 HCFs participated, including 14,968 wards and 203,840 HCWs. At an institutional level, the POA was 88%, covering SPs promotion (91%), procedures (99%), and SPs evaluation (63%). At the ward level, the POA was 94%, covering procedures (95%) and resources (93%). HCWs reported the best compliance for changing gloves between patients (94.5% "always"), and the worst compliance for the use of gloves for intramuscular injection and the use of eye protection in cases of blood exposure risk (34.5% and 24.4% of "always," respectively). CONCLUSIONS: A literature review found no other study of SPs that included such a large study group. These results led to SPs promotion actions at local and regional levels. Reinforcement of SPs observance will be prioritized in the next national program from the French Ministry of Health.

Detection of hospital outbreaks of influenza-like illness based on excess of incidence rates compared to the community.

The risk of nosocomial influenza-like illness (noso-ILI) compared with that of community-acquired ILI was calculated during 3 influenza seasons (2004-2007) at a 1100-bed university hospital with a total of 21,519 hospitalized patients. Outbreaks of noso-ILI occurred in each season, although a protective effect against noso-ILI was also identified for other wards.

Improving prediction of surgical site infection risk with multilevel modeling.

BACKGROUND: Surgical site infection (SSI) surveillance is a key factor in the elaboration of strategies to reduce SSI occurrence and in providing surgeons with appropriate data feedback (risk indicators, clinical prediction rule). AIM: To improve the predictive performance of an individual-based SSI risk model by considering a multilevel hierarchical structure. PATIENTS AND METHODS: Data were collected anonymously by the French SSI active surveillance system in 2011. An SSI diagnosis was made by the surgical teams and infection control practitioners following standardized criteria. A random 20% sample comprising 151 hospitals, 502 wards and 62280 patients was used. Three-level (patient, ward, hospital) hierarchical logistic regression models were initially performed. Parameters were estimated using the simulation-based Markov Chain Monte Carlo procedure. RESULTS: A total of 623 SSI were diagnosed (1%). The hospital level was discarded from the analysis as it did not contribute to variability of SSI occurrence (p  = 0.32). Established individual risk factors (patient history, surgical procedure and hospitalization characteristics) were identified. A significant heterogeneity in SSI occurrence between wards was found (median odds ratio [MOR] 3.59, 95% credibility interval [CI] 3.03 to 4.33) after adjusting for patient-level variables. The effects of the follow-up duration varied between wards (p<10-9), with an increased heterogeneity when follow-up was <15 days (MOR 6.92, 95% CI 5.31 to 9.07]). The final two-level model significantly improved the discriminative accuracy compared to the single level reference model (p<10-9), with an area under the ROC curve of 0.84. CONCLUSION: This study sheds new light on the respective contribution of patient-, ward- and hospital-levels to SSI occurrence and demonstrates the significant impact of the ward level over and above risk factors present at patient level (i.e., independently from patient case-mix).

Use of surveillance data to identify target populations for Staphylococcus aureus vaccines and prevent surgical site infections: a pilot study.

The development of anti-staphylococcal vaccines is nowadays a priority to prevent surgical site infections (SSI). The objective of the present study was to identify a potential target population by assessing surveillance data on surgery patients for possible anti-staphylococcal vaccine administration. Individuals at high risk of SSI by Staphylococcus aureus (SA) were targeted by the French SSI Surveillance Network in south-eastern France between 2008 and 2011. Among 238,470 patients, those undergoing primary total hip replacement appeared to be an interesting and healthy enough population for anti-staphylococcal vaccine testing. These male patients, subjected to multiple procedures and with American Society of Anesthesiologists score>2, had a probability of SA SSI about 21 times higher than females with no severe systemic disease and no multiple procedures. Our study indicates that surveillance data on SSI might be an interesting epidemiological source for planning vaccine trials to prevent nosocomial infections.

Prevalence and risk factors for HIV, hepatitis B virus, and syphilis among pregnant women in Mayotte, Indian Ocean, 2008-2009.

OBJECTIVE: To assess the prevalence and risk factors for HIV, hepatitis B virus (HBV), and syphilis among pregnant women living on the Indian Ocean island of Mayotte. METHODS: A cross-sectional survey was conducted among 671 pregnant women at 11 prenatal clinics on Mayotte between September 15, 2008, and September 27, 2009. Sociodemographic and behavioral characteristics were collected by interviewer-administered questionnaire. Blood samples were obtained for HIV, HBV, and syphilis testing. Risk factors were analyzed by exact logistic regression. RESULTS: No prevalent case of HIV infection was detected among the study population. The prevalence of HBV surface antigen and active syphilis (defined as a positive test result by both rapid plasma reagin and Treponema pallidum hemagglutination assays) was 3.4% and 2.1%, respectively. A positive HBV surface antigen test was associated with being born in Comoros and having sex with a casual partner during the previous year. Lack of education and a history of sexually transmitted infections in the past 5 years were associated with active syphilis. CONCLUSION: The continuing low prevalence of HIV and high prevalence of sexually transmitted infections among pregnant women on Mayotte confirmed the so-called "Indian Ocean paradox."

A multiplicative hazard regression model to assess the risk of disease transmission at hospital during community epidemics.

BACKGROUND: During community epidemics, infections may be imported within hospital and transmitted to hospitalized patients. Hospital outbreaks of communicable diseases have been increasingly reported during the last decades and have had significant consequences in terms of patient morbidity, mortality, and associated costs. Quantitative studies are thus needed to estimate the risks of communicable diseases among hospital patients, taking into account the epidemiological process outside, hospital and host-related risk factors of infection and the role of other patients and healthcare workers as sources of infection. METHODS: We propose a multiplicative hazard regression model to analyze the risk of acquiring a communicable disease by patients at hospital. This model derives from epidemiological data on communicable disease epidemics in the community, hospital ward, patient susceptibility to infection, and exposure of patients to infection at hospital. The model estimates the relative effect of each of these factors on a patient's risk of communicable disease. RESULTS: Using individual data on patients and health care workers in a teaching hospital during the 2004-2005 influenza season in Lyon (France), we show the ability of the model to assess the risk of influenza-like illness among hospitalized patients. The significant effects on the risk of influenza-like illness were those of old age, exposure to infectious patients or health care workers, and a stay in a medical care unit. CONCLUSIONS: The proposed multiplicative hazard regression model could be an interesting epidemiological tool to quantify the risk of communicable disease at hospital during community epidemics and the uncertainty inherent in such quantification. Furthermore, key epidemiological, environmental, host, or exposure factors that influence this risk can be identified.

Risk of influenza-like illness in an acute health care setting during community influenza epidemics in 2004-2005, 2005-2006, and 2006-2007: a prospective study.

BACKGROUND: The person-to-person transmission of influenza-like illness (ILI) and influenza has been described mostly in long-term care units. Studies in acute hospital settings are rare and mostly retrospective. METHODS: We prospectively estimated the relative risk (RR) of hospital-acquired (HA) ILI during hospitalization according to in-hospital exposures to contagious individuals. Surveillance of ILI and laboratory-confirmed influenza was undertaken at Edouard Herriot Hospital (1100 beds) during 3 influenza seasons. A total of 21 519 patients and 2153 health care workers (HCWs) from 2004 to 2007 were included. The RR of HA-ILI in patients was calculated according to exposure to other contagious patients and HCWs. RESULTS: For patients exposed to at least 1 contagious HCW compared with those with no documented exposure in the hospital, the RR of HA-ILI was 5.48 (95% confidence interval [CI], 2.09-14.37); for patients exposed to at least 1 contagious patient, the RR was 17.96 (95% CI, 10.07-32.03); and for patients exposed to at least 1 contagious patient and 1 contagious HCW, the RR was 34.75 (95% CI, 17.70-68.25). CONCLUSIONS: Hospitalized patients exposed to potentially infectious patients and HCWs with ILI inside the hospital are at greater risk for HA-ILI. Such results identify priorities regarding preventive measures for seasonal or pandemic influenza.

Fatal nosocomial Legionella pneumophila infection due to exposure to contaminated water from a washbasin in a hematology unit.

A fatal nosocomial infection with Legionella pneumophila serogroup 5 occurred in a patient with leukemia. Isolates recovered from both the potable water supply and the patient showed an identical genomic profile. With no other exposure identified, the water from the washbasin was evidently the source of infection.

Early- and late-onset ventilator-associated pneumonia acquired in the intensive care unit: comparison of risk factors.

PURPOSE: To compare risk factors of early- (E) and late-onset (L) ventilator-associated pneumonia (VAP). MATERIALS AND METHODS: An epidemiological survey based on a nosocomial infection surveillance program of 11 intensive care units (ICUs) of university teaching hospitals in Lyon, France, was conducted. A total of 7236 consecutive ventilated patients, older than 18 years and hospitalized in ICUs for at least 48 hours, were studied between 1996 and 2002. Data during ICU stay, patient-dependent risk factors, device exposure, nosocomial infections occurrence, and outcome were collected. The cutoff point definition between E-VAP (six days) was based on the daily hazard rate of VAP. RESULTS: The VAP incidence rate was 13.1%, 356 (37.6%) E-VAP (within 6 days of admission) and 590 (62.4%) L-VAP were reported. Independent risk factor for E-VAP vs L-VAP was surgical diagnostic category (odds ratio [OR], 1.49 [95% confidence interval, 1.07-2.07]), whereas independent risk factors for L-VAP vs E-VAP were older age (OR, 1.01 [1.01-1.02]), high Simplified Acute Physiology Score II (OR, 1.01 [1.00-1.02]), infection on admission (OR=2.22 [1.61-3.03]), another nosocomial infection before VAP (OR, 5.88 [3.33-11.11]), and exposure to central venous catheter before VAP (OR, 4.76 [1.04-20.00]). CONCLUSIONS: E-VAP and L-VAP have different risk factors, highlighting the need for developing specific preventive measures.