An unusual outbreak of parvovirus B19 infections, France, 2023 to 2024.

From April 2023 to May 2024, an unusual epidemic of parvovirus B19 (B19V) infections occurred in France. The number of B19V IgM-positive serologies was four times higher than in the previous epidemic in 2019. Clinical data from emergency networks corroborated this observation. Morbidity and mortality consequences were observed in children through all data sources. In adults, the increase was only observed in laboratory-confirmed data. Physicians and decisionmakers should be informed in order to better prevent, diagnose and manage at-risk patients.

Tuberculosis incidence in foreign-born people residing in European countries in 2020.

BackgroundEuropean-specific policies for tuberculosis (TB) elimination require identification of key populations that benefit from TB screening.AimWe aimed to identify groups of foreign-born individuals residing in European countries that benefit most from targeted TB prevention screening.MethodsThe Tuberculosis Network European Trials group collected, by cross-sectional survey, numbers of foreign-born TB patients residing in European Union (EU) countries, Iceland, Norway, Switzerland and the United Kingdom (UK) in 2020 from the 10 highest ranked countries of origin in terms of TB cases in each country of residence. Tuberculosis incidence rates (IRs) in countries of residence were compared with countries of origin.ResultsData on 9,116 foreign-born TB patients in 30 countries of residence were collected. Main countries of origin were Eritrea, India, Pakistan, Morocco, Romania and Somalia. Tuberculosis IRs were highest in patients of Eritrean and Somali origin in Greece and Malta (both > 1,000/100,000) and lowest among Ukrainian patients in Poland (3.6/100,000). They were mainly lower in countries of residence than countries of origin. However, IRs among Eritreans and Somalis in Greece and Malta were five times higher than in Eritrea and Somalia. Similarly, IRs among Eritreans in Germany, the Netherlands and the UK were four times higher than in Eritrea.ConclusionsCountry of origin TB IR is an insufficient indicator when targeting foreign-born populations for active case finding or TB prevention policies in the countries covered here. Elimination strategies should be informed by regularly collected country-specific data to address rapidly changing epidemiology and associated risks.

Active tuberculosis screening among the displaced population fleeing Ukraine, France, February to October 2022.

Persons fleeing Ukraine since February 2022 have potentially higher risk of tuberculosis (TB) vs all European Union countries. Interest of active TB screening among this population is debated and not widely adopted. In this screening intervention by a network of TB centres in France, the number needed to screen (NNS) was 862 to find one case. This experience shows that this strategy may be relevant for TB control in situations of massive displacement, similar to that following the Russian invasion.

Diphtheria-Tetanus-Polio, Measles-Mumps-Rubella, and Hepatitis B Vaccination Coverage and Associated Factors among Homeless Children in the Paris Region in 2013: Results from the ENFAMS Survey.

Background: The number of homeless families has increased considerably since the 1990s in France. We aimed to estimate the homeless children vaccination coverage (VC) for diphtheria, tetanus, polio, measles-mumps-rubella and hepatitis B and identify factors associated with insufficient VC according to birthplace. Methods: A cross-sectional survey was conducted among homeless shelter families in the greater Paris area. A nurse conducted face-to-face interviews and collected vaccination records. We analyzed factors associated with insufficient VC, stratified by birthplace and vaccine, using robust Poisson regression. Results: The study included 214 children born in France and 236 born outside France. VC in French-born homeless children was high (>90% at 24 months for most vaccinations) and similar to levels observed in the general population, whereas VC in those born outside France was low (<50% at 24 months for all vaccines). Factors significantly associated with insufficient VC among children born outside France were age, parents with French-language difficulties, and changing residence at least twice in the previous year. Children in contact with the healthcare system at least once in the previous year had significantly higher VC, irrespective of vaccine and birthplace. Conclusion: Special attention should be paid to homeless children born outside France, with recent European and French recommendations confirming the need for catch-up vaccination in children with undocumented VC.

Tuberculosis treatment outcomes of notified cases: trends and determinants of potential unfavourable outcome, France, 2008 to 2014.

BackgroundSurveillance of tuberculosis (TB) treatment outcome, for which reporting has been mandatory in France since 2007, is a key component of TB control.AimWe aimed to present surveillance data for non-multidrug-resistant (MDR) cases reported between 2008 and 2014, and identify factors associated with potentially unfavourable treatment outcome.MethodsPatients were classified according to their treatment outcome 12 months after beginning treatment. Poisson regression with a robust error variance was used to investigate factors associated with potentially unfavourable treatment outcome. Missing data were handled using multiple imputation.ResultsA total of 22,526 cases were analysed for treatment outcome. Information available on treatment outcome increased between 2008 (60%) and 2014 (71%) (p < 0.001). During this period, 74.1% of cases completed treatment, increasing from 73.0% in 2008 to 76.9% in 2014 (p < 0.001). This proportion was 74.0% in culture-positive pulmonary cases. Overall, 19.8% of cases had a potentially unfavourable outcome, including lost-to-follow-up, transferred out, still on treatment, death related to TB and interrupted treatment. Potentially unfavourable outcome was significantly associated with TB severity, residing in congregate settings, homelessness, being a smear-positive pulmonary case, being born abroad and residing in France for < 2 years, history of previous anti-TB treatment and age > 85 years.ConclusionMonitoring of treatment outcome is improving over time. The increase in treatment completion over time suggests improved case management. However, treatment outcome monitoring needs to be strengthened in cases belonging to population groups where the percentage of unfavourable outcome is the highest and in cases where surveillance data shows poorer documented follow-up.

The use of reimbursement data for timely monitoring of vaccination coverage: the example of human papillomavirus vaccine following public concerns about vaccine safety.

BACKGROUND: Since 2011 public concerns about Human Papillomavirus (HPV) vaccination safety and efficacy arose in France. We explored the relevance of using vaccines reimbursement data to assess the impact of those public concerns on vaccination coverage. METHODS: We used the Permanent Sample of Beneficiaries which was, at the time of the study, a representative sample of 1/97(th) health insurance beneficiaries of the main Social Security scheme, the General Health Insurance Scheme, covering approximately 77 % of the French resident population. We estimated HPV vaccination coverage among girls born between 1995 and 1999 at their 15(th), 16(th) and 17(th) birthday. RESULTS: The coverage for complete vaccination among 16 years old girls decreased from 26.5 % in the first semester of 2011 to 18.6 % in the first semester of 2014. CONCLUSIONS: HPV vaccination coverage was already low in 2011 and continued to decrease thereafter. Vaccines reimbursement data allowed us to reactively monitor the impact of the controversy on vaccination coverage and design counteracting measures.

Baseline data of parasite clearance in patients with falciparum malaria treated with an artemisinin derivative: an individual patient data meta-analysis.

BACKGROUND: Artemisinin resistance in Plasmodium falciparum manifests as slow parasite clearance but this measure is also influenced by host immunity, initial parasite biomass and partner drug efficacy. This study collated data from clinical trials of artemisinin derivatives in falciparum malaria with frequent parasite counts to provide reference parasite clearance estimates stratified by location, treatment and time, to examine host factors affecting parasite clearance, and to assess the relationships between parasite clearance and risk of recrudescence during follow-up. METHODS: Data from 24 studies, conducted from 1996 to 2013, with frequent parasite counts were pooled. Parasite clearance half-life (PC1/2) was estimated using the WWARN Parasite Clearance Estimator. Random effects regression models accounting for study and site heterogeneity were used to explore factors affecting PC1/2 and risk of recrudescence within areas with reported delayed parasite clearance (western Cambodia, western Thailand after 2000, southern Vietnam, southern Myanmar) and in all other areas where parasite populations are artemisinin sensitive. RESULTS: PC1/2 was estimated in 6975 patients, 3288 of whom also had treatment outcomes evaluate d during 28-63 days follow-up, with 93 (2.8 %) PCR-confirmed recrudescences. In areas with artemisinin-sensitive parasites, the median PC1/2 following three-day artesunate treatment (4 mg/kg/day) ranged from 1.8 to 3.0 h and the proportion of patients with PC1/2 >5 h from 0 to 10 %. Artesunate doses of 4 mg/kg/day decreased PC1/2 by 8.1 % (95 % CI 3.2-12.6) compared to 2 mg/kg/day, except in populations with delayed parasite clearance. PC1/2 was longer in children and in patients with fever or anaemia at enrolment. Long PC1/2 (HR = 2.91, 95 % CI 1.95-4.34 for twofold increase, p < 0.001) and high initial parasitaemia (HR = 2.23, 95 % CI 1.44-3.45 for tenfold increase, p < 0.001) were associated independently with an increased risk of recrudescence. In western Cambodia, the region with the highest prevalence of artemisinin resistance, there was no evidence for increasing PC1/2 since 2007. CONCLUSIONS: Several factors affect PC1/2. As substantial heterogeneity in parasite clearance exists between locations, early detection of artemisinin resistance requires reference PC1/2 data. Studies with frequent parasite count measurements to characterize PC1/2 should be encouraged. In western Cambodia, where PC1/2 values are longest, there is no evidence for recent emergence of higher levels of artemisinin resistance.

The effect of dosing strategies on the therapeutic efficacy of artesunate-amodiaquine for uncomplicated malaria: a meta-analysis of individual patient data.

BACKGROUND: Artesunate-amodiaquine (AS-AQ) is one of the most widely used artemisinin-based combination therapies (ACTs) to treat uncomplicated Plasmodium falciparum malaria in Africa. We investigated the impact of different dosing strategies on the efficacy of this combination for the treatment of falciparum malaria. METHODS: Individual patient data from AS-AQ clinical trials were pooled using the WorldWide Antimalarial Resistance Network (WWARN) standardised methodology. Risk factors for treatment failure were identified using a Cox regression model with shared frailty across study sites. RESULTS: Forty-three studies representing 9,106 treatments from 1999-2012 were included in the analysis; 4,138 (45.4%) treatments were with a fixed dose combination with an AQ target dose of 30 mg/kg (FDC), 1,293 (14.2%) with a non-fixed dose combination with an AQ target dose of 25 mg/kg (loose NFDC-25), 2,418 (26.6%) with a non-fixed dose combination with an AQ target dose of 30 mg/kg (loose NFDC-30), and the remaining 1,257 (13.8%) with a co-blistered non-fixed dose combination with an AQ target dose of 30 mg/kg (co-blistered NFDC). The median dose of AQ administered was 32.1 mg/kg [IQR: 25.9-38.2], the highest dose being administered to patients treated with co-blistered NFDC (median = 35.3 mg/kg [IQR: 30.6-43.7]) and the lowest to those treated with loose NFDC-25 (median = 25.0 mg/kg [IQR: 22.7-25.0]). Patients treated with FDC received a median dose of 32.4 mg/kg [IQR: 27-39.0]. After adjusting for reinfections, the corrected antimalarial efficacy on day 28 after treatment was similar for co-blistered NFDC (97.9% [95% confidence interval (CI): 97.0-98.8%]) and FDC (98.1% [95% CI: 97.6%-98.5%]; P = 0.799), but significantly lower for the loose NFDC-25 (93.4% [95% CI: 91.9%-94.9%]), and loose NFDC-30 (95.0% [95% CI: 94.1%-95.9%]) (P < 0.001 for all comparisons). After controlling for age, AQ dose, baseline parasitemia and region; treatment with loose NFDC-25 was associated with a 3.5-fold greater risk of recrudescence by day 28 (adjusted hazard ratio, AHR = 3.51 [95% CI: 2.02-6.12], P < 0.001) compared to FDC, and treatment with loose NFDC-30 was associated with a higher risk of recrudescence at only three sites. CONCLUSIONS: There was substantial variation in the total dose of amodiaquine administered in different AS-AQ combination regimens. Fixed dose AS-AQ combinations ensure optimal dosing and provide higher antimalarial treatment efficacy than the loose individual tablets in all age categories.

Vaccine knowledge in students in Paris, France, and surrounding regions.

INTRODUCTION: In France, young adults are legally freed from parental authority at the age of 18 years and are, thus, responsible for their own vaccine record. This young adult population is more frequently exposed to vaccine-preventable infectious diseases. OBJECTIVE: To determine the factors associated with students' knowledge of the interval between two antitetanus boosters and their report of having up-to-date vaccinations. METHODS: In April 2009, a survey was conducted involving a random sample of students between 18 and 25 years of age eating lunch at university dining facilities in Paris and its suburbs (Ile de France). RESULTS: Among the 677 students approached, 583 agreed to participate. Only 207 (36%) of respondents knew the recommended dosing interval between two doses of tetanus vaccine booster (10 years). The majority of students (69%) reported having up-to-date vaccinations. Declaring having up-to-date vaccinations was significantly associated with having a general practitioner (OR 3.03 [95% CI 1.69 to 5.55]). Health care students were significantly more likely to know the decennial interval between two antitetanus boosters (OR 2 [95% CI 1.28 to 3.25]). Most of responding students (n=519 [89%]) believed that vaccines were very useful. CONCLUSIONS: An overall lack of knowledge of vaccines was observed among this student population. Health care providers, such as GPs and university medical practice staff, who interact with these young individuals have an essential role to promote better vaccination coverage in this population.

INTRODUCTION: En France, les jeunes adultes sont légalement libérés de l'autorité parentale à 18 ans et deviennent donc responsables de leur dossier de vaccination. La population de jeunes adultes est davantage exposée aux maladies infectieuses évitables par la vaccination. OBJECTIF: Déterminer les facteurs associés aux connaissances des étudiants sur l'intervalle entre les deux doses de rappel du vaccin contre le tétanos et sur leur déclaration d'avoir une couverture vaccinale. MÉTHODOLOGIE: En avril 2009, un sondage a été mené auprès d'un échantillon aléatoire d'étudiants de 18 à 25 ans qui, le midi, mangent aux cafétérias universitaires de Paris et des banlieues (Île de France). RÉSULTATS: Sur les 677 étudiants abordés, 583 ont accepté de participer. Seulement 207 des répondants (36 %) connaissaient l'intervalle recommandé entre deux doses de rappel du vaccin contre le tétanos (dix ans). La majorité des étudiants (69 %) déclarai avoir une couverture vaccinale à jour. Cette déclaration s'associait de manière significative au fait d'avoir un praticien général (RC 3,03 95 % IC 1,69 à 5,55]). Les étudiants du milieu de la santé étaient considérablement plus enclins à connaître l'intervalle de dix ans entre deux doses de rappel du vaccin antitétanique (RC 2 [95 % IC 1,28 à 3,25]). La plupart des étudiants répondants (n=519 [89 %]) croyaient en l'utilité des vaccins. CONCLUSIONS: Les chercheurs ont constaté une ignorance globale des vaccins au sein de cette population de patients. Les dispensateurs de soins, tels que les praticiens généraux et le personnel médical en milieu universitaire, qui dialoguent avec ces jeunes, ont un rôle essentiel à jouer pour promouvoir une meilleure couverture vaccinale au sein de cette population.

Family history of immigration from a tuberculosis endemic country and low family income are associated with a higher BCG vaccination coverage in Ile-de-France region, France.

After withdrawal of multipuncture BCG device from the French market in January 2006, vaccination coverage (VC) with the intradermal device has dropped and since remained sub-optimal in Ile-de-France, the only region of mainland France where BCG is recommended to all children. We conducted a cross-sectional study to identify socio-economic factors associated with BCG VC in children of Paris metropolitan area born after January 2006. Two-stage random sampling was used to include 425 children up to 5 years old from Paris and its suburbs. Information was collected through face-to-face interviews and vaccination status confirmed by a vaccination document. Poisson regression analyzed the association between VC and potential determinants. VC of children from families with the lowest incomes (first quartile of family income/consumption unit (CU) (<883 €) was close to 100% regardless of family origin. In families with higher incomes (≥ 883 €/CU), VC was significantly higher among children born to families from a tuberculosis highly endemic country (98.2%) compared with other children (76.2%) (p=0.004). Children of low socio-economic background as well as those with a family history of immigration, regardless of family income, are correctly identified as being at high risk of tuberculosis and properly vaccinated with BCG in this area.

Vaccine coverage of healthcare students in hospitals of the Paris region in 2009: the Studyvax survey.

INTRODUCTION: Healthcare students should comply with the same vaccination recommendations as employed healthcare professionals. Vaccination coverage data for healthcare students are lacking MATERIALS AND METHODS: This cross-sectional survey was carried out on medical, nursing and midwifery students in 15 hospitals of the Assistance Publique - Hôpitaux de Paris with a maternity ward. All midwifery students were surveyed, and a subset of medical and nursing students were selected from 10 hospitals by three-stage random sampling. Data were collected by face-to-face interviews and verified from health records. RESULTS: A total of 432 students were included in the study (178 medical, 147 nursing, 107 midwifery), of whom 376 (87%) had proof of vaccination. The confirmed coverage for compulsory vaccinations was 96.9% for the booster dose of diphtheria-tetanus-poliomyelitis vaccine, 93.6% for BCG and 91.8% for at least three doses of hepatitis B. The coverage for recommended vaccinations confirmed by a vaccine booklet was 44% for pertussis (booster at 11-13 or 16-18 years of age), and 79.3% and 49.6% for the first and second doses of measles, respectively. The rate for influenza vaccination was 39.6%, based on self-reported information. Of the 27 students without any history of varicella infection, six had been vaccinated. DISCUSSION: Vaccination coverage of healthcare students is high for compulsory vaccinations, but largely insufficient for recommended vaccinations. Increased awareness regarding the required vaccinations is necessary in this population, as well as stronger enforcement prior to initiating clinical work.

Vaccination coverage of health care personnel working in health care facilities in France: results of a national survey, 2009.

We conducted a national cross-sectional survey to investigate vaccination coverage (VC) in health care personnel (HCP) working in clinics and hospitals in France. We used a two-stage stratified random sampling design to select 1127 persons from 35 health care settings. Data were collected by face-to-face interviews and completed using information gathered from the occupational health doctor. A total of 183 physicians, 110 nurses, 58 nurse-assistants and 101 midwives were included. VC for compulsory vaccinations was 91.7% for hepatitis B, 95.5% for the booster dose of diphtheria-tetanus-polio (DTP), 94.9% for BCG. For non-compulsory vaccinations, coverage was 11.4% for the 10 year booster of the DTP pertussis containing vaccine, 49.7% for at least one dose of measles, 29.9% for varicella and 25.6% for influenza. Hepatitis B VC did not differ neither between HCP working in surgery and HCP in other sectors, nor in surgeons and anaesthesiologists compared to physicians working in medicine. Young HCP were better vaccinated for pertussis and measles (p<0.01), and those working in an obstetric or a paediatric ward were better vaccinated for influenza and pertussis (p<0.01). HCP are overall well covered by compulsory vaccinations, whereas VC for non-compulsory vaccinations is very insufficient. The vaccination policy regarding these latter vaccinations should be reinforced in France.

Incidence of H1N1 2009 virus infection through the analysis of paired plasma specimens among blood donors, France.

BACKGROUND: Knowledge of the age-specific prevalence of seroprotection and incidence of seroconversion infection is necessary to complement clinical surveillance data and statistical models. It provides the basis for estimating the future impact of influenza A (H1N1pdm09) and implementing appropriate prevention and response strategies. METHODS: Using a cross-sectional design, two-stage stratified sampling and paired plasma samples, we estimated the age-specific prevalence of a protective level of H1N1pdm09 antibodies in the French adult population before and after the 2009/10 pandemic, and the proportion of those susceptible that seroconverted due to infection, from a single sample of 1,936 blood donors aged 20-70 years in mainland France in June 2010. Samples with a haemagglutination inhibition (HI) titre ≥1∶40 were considered seropositive, and seroconversion due to infection was defined as a 4-fold increase in titre in the absence of H1N1pdm09 vaccination or pre-pandemic seropositivity. RESULTS: Out of the 1,936 donors, 1,708 were included in the analysis. Seroprevalence before the pandemic was 6.7% (95% CI 5.0, 8.9) with no significant differences by age-group (p = 0.3). Seroprevalence afterwards was 23.0% (95% CI 17.7, 29.3) with 20-29 year olds having a higher level than older groups (p<0.001). Seroconversion due to infection was 12.2% (95% CI 6.9, 20.5). Younger age-group, vaccination against H1N1 and being seropositive before the pandemic were strongly associated with post-pandemic seropositivity. CONCLUSIONS: Before the 2009/2010 winter influenza season, only 6.7% of the French mainland population aged 20-70 had a level of antibodies usually considered protective. During the first pandemic wave, 12.2% of the population seroconverted due to infection and the seroprevalence after the wave rose to 23%, either due to prepandemic seropositivity, infection or vaccination. This relatively low latter figure contributed to an extension of target groups for influenza vaccination for the 2010/2011 season.

Influenza vaccination coverage one year after the A(H1N1) influenza pandemic, France, 2010-2011.

We report influenza vaccination coverage in target groups for the 2010-2011 influenza season, one year after the A(H1N1) pandemic. Data were collected through a one-stage cross-sectional national random telephone survey conducted in January 2011 among a sample of the population of mainland France connected to a land telephone line. Influenza vaccination coverage was below 75%, ranging from 28% for health professionals to 71% in the "65+" group with an underlying condition. Coverage was higher in the "65+" compared to the "<65" with an underlying condition. It was not significantly lower compared to the previous season. Our results do not suggest that the controversies related to the pandemic vaccination campaign of 2009-2010 have had a negative impact on subsequent seasonal influenza vaccination coverage.

Influenza vaccination coverage against seasonal and pandemic influenza and their determinants in France: a cross-sectional survey.

BACKGROUND: Following the emergence of the influenza A(H1N1)2009 virus, the French ministry of health decided to offer free vaccination against pandemic influenza to the entire French population. Groups of people were defined and prioritised for vaccination. METHODS: We took a random sample of the population of mainland France and conducted a retrospective cross-sectional telephone survey to estimate vaccination coverage against seasonal and pandemic influenza and to identify determinants of these vaccinations. RESULTS: 10,091 people were included in the survey. Overall seasonal influenza vaccination coverage (IVC) remained stable in the population from the 2008-2009 season to the 2009-2010 season reaching 20.6% and 20.8% respectively. Overall pandemic IVC in the French population is estimated to be 11.1% (CI95%: 9.8 - 12.4). The highest pandemic IVC was observed in the 0-4 years age group. For individuals with health conditions associated with higher risk of influenza, pandemic IVC was estimated to be 12.2% (CI95%: 9.8 - 15.1). The main determinants associated with pandemic influenza vaccine uptake were: living in a household with a child < 5 years ORadj: 2.0 (CI95%: 1.3 - 3.1) or with two children < 5 years or more, ORadj: 2.7 (CI95%: 1.4 - 5.1), living in a household where the head of the family is university graduate (>2 years), ORadj: 2.5 (CI95%: 1.5 - 4.1), or has a higher professional and managerial occupation, ORadj: 3.0 (CI95%: 1.5 - 5.5) and being vaccinated against seasonal influenza, ORadj: 7.1 (CI95%: 5.1 - 10.0). Being an individual with higher risk for influenza was not a determinant for pandemic influenza vaccine uptake. These determinants are not the same as those for seasonal influenza vaccination. CONCLUSIONS: Overall A(H1N1)2009 influenza vaccine uptake remained low, particularly among individuals with higher risk for influenza and was lower than that observed for seasonal influenza. The reasons behind people's reluctance to be vaccinated need to be investigated further.

Population and risk group uptake of H1N1 influenza vaccine in mainland France 2009-2010: results of a national vaccination campaign.

A mass vaccination campaign against influenza A/H1N1 was launched in France in October 2009. Vaccination was offered free of charge to the entire population according to a pre-defined order of priority. Demographic data and data on vaccinations given were recorded in a dedicated database. We analysed vaccine uptake by age, sex and region in the overall population and in certain risk groups, including pregnant women. Overall vaccine uptake was 8% and varied by age-group and sex. Vaccine uptake in pregnant women was 22.7%. These low uptakes may reflect controversies around the vaccine and vaccination policy and have important implications for future pandemic vaccination strategies.

Influenza vaccination coverage of healthcare workers and residents and their determinants in nursing homes for elderly people in France: a cross-sectional survey.

BACKGROUND: Nursing home residents bear a substantial burden of influenza morbidity and mortality. Vaccination of residents and healthcare workers (HCWs) is the main strategy for prevention. Despite recommendations, influenza vaccination coverage among HCWs remains generally low. METHODS: During the 2007-2008 influenza season, we conducted a nationwide survey to estimate influenza vaccination coverage of HCWs and residents in nursing homes for elderly people in France and to identify determinants of vaccination rates. Multivariate analysis were performed with a negative binomial regression. RESULTS: Influenza vaccination coverage rates were 33.6% (95% CI: 31.9-35.4) for HCWs and 91% (95% CI: 90-92) for residents. Influenza vaccination uptake of HCWs varied by occupational category. Higher vaccination coverage was found in private elderly care residences, when free vaccination was offered (RR: 1.89, 1.35-2.64), in small nursing homes (RR: 1.54, 1.31-1.81) and when training sessions and staff meetings on influenza were organized (RR: 1.20, 1.11-1.29). The analysis by occupational category showed that some determinants were shared by all categories of professionals (type of nursing homes, organization of training and staff meetings on influenza). Higher influenza vaccination coverage was found when free vaccination was offered to recreational, cleaning, administrative staff, nurses and nurse assistants, but not for physicians. CONCLUSIONS: This nationwide study assessed for the first time the rate of influenza vaccination among residents and HCWs in nursing homes for elderly in France. Better communication on the current recommendations regarding influenza vaccination is needed to increase compliance of HCWs. Vaccination programmes should include free vaccination and education campaigns targeting in priority nurses and nurse assistants.

In vivo parasitological measures of artemisinin susceptibility.

Parasite clearance data from 18,699 patients with falciparum malaria treated with an artemisinin derivative in areas of low (n=14,539), moderate (n=2077), and high (n=2083) levels of malaria transmission across the world were analyzed to determine the factors that affect clearance rates and identify a simple in vivo screening measure for artemisinin resistance. The main factor affecting parasite clearance time was parasite density on admission. Clearance rates were faster in high-transmission settings and with more effective partner drugs in artemisinin-based combination treatments (ACTs). The result of the malaria blood smear on day 3 (72 h) was a good predictor of subsequent treatment failure and provides a simple screening measure for artemisinin resistance. Artemisinin resistance is highly unlikely if the proportion of patients with parasite densities of <100,000 parasites/microL given the currently recommended 3-day ACT who have a positive smear result on day 3 is <3%; that is, for n patients the observed number with a positive smear result on day 3 does not exceed (n + 60)/24.