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Chikungunya virus (CHIKV) emerged in the Caribbean island of Saint-Martin in December 2013. We implemented a hospital-based surveillance system to detect and describe CHIKV cases including severe forms of the infection and deaths in the islands of Martinique and Guadeloupe. A case was defined as a patient with a CHIKV laboratory confirmation cared for in a public hospital for chikungunya for at least 24 hours, and a severe CHIKV case was defined as a CHIKV case presenting one or more organ failures. Sociodemographic, clinical, and laboratory data were collected and cases classified into severe or nonsevere based on medical records. From December 2013 to January 2015, a total of 1,836 hospitalized cases were identified. Rate of hospital admissions for CHIKV infection was 60 per 10,000 suspected clinical CHIKV cases and severity accounted for 12 per 10,000. A total of 74 deaths related to CHIKV infection occurred. Infants and elderly people were more frequently hospitalized compared with others and severity was more frequently reported in elderly subjects and subjects with underlying health condition. Fifteen neonatal infections consecutive to mother-to-child transmission were diagnosed, seven of which were severe. The most vulnerable groups of the population, such as the elderly, infants, individuals with comorbidities, and pregnant women, should remain the main targets of public health priorities.

BACKGROUND:Leptospirosis is a neglected zoonosis affecting mainly tropical and subtropical regions worldwide, particularly South America and the Caribbean. As in many other countries, under-reporting of cases was suspected in the French West Indies because of inadequate access to diagnostic tests for the general population. METHODOLOGY/PRINCIPAL FINDINGS:In order to estimate the real incidence of leptospirosis in Guadeloupe and Martinique, a study was performed in 2011 using the three prevailing available biological tests for diagnosis: Microscopic Agglutination Test (MAT), IgM ELISA and PCR. The study investigated inpatients and outpatients and used active case ascertainment from data provided by a general practitioners' sentinel network. The epidemiology of the disease was also described in terms of severity and demographic characteristics. Leptospirosis incidence was estimated at 69.4 (95%CI 47.6-91.1) and 60.6 (95%CI 36.3-85.0) annual cases per 100,000 inhabitants in Guadeloupe and Martinique, respectively, which was 3 and 4 times higher than previous estimations. CONCLUSION/SIGNIFICANCE:Inclusion of PCR and IgM ELISA tests for diagnosis of leptospirosis resulted in improved sensitivity in comparison with MAT alone. Our results highlighted the substantial health burden of the disease in these two territories and the importance of access to appropriate laboratory tests. Based on our results, PCR and IgM ELISA tests have now been included in the list of tests reimbursed by the national system of social security insurance in France. Our results also underline the relevance of implementing an integrated strategy for the surveillance, prevention and control of leptospirosis in the French West Indies.

At the end of 2013, chikungunya virus (CHIKV) emerged in Saint Martin Island, Caribbean. The Asian lineage was identified. Seven months after this introduction, the seroprevalence was 16.9% in the population of Saint Martin and 39.0% of infections remained asymptomatic. This moderate attack rate and the apparent limited size of the outbreak in Saint Martin could be explained by control measures involved to lower the exposure of the inhabitants. Other drivers such as climatic factors and population genetic factors should be explored. The substantial rate of asymptomatic infections recorded points to a potential source of infection that can both spread in new geographic areas and maintain an inconspicuous endemic circulation in the Americas.

Background Key symptoms observed during the febrile phase of dengue may identify patients who are likely to progress to severe disease. Objectives To test this hypothesis, we examined the relationships between symptoms reported by patients at presentation and the development of severe outcomes. Study design Retrospective analysis of data recorded prospectively in 560 adult dengue patients admitted to an emergency department. A logistic regression analysis was used to quantify the association between symptoms reported at presentation and outcome. Results Plasma leakage was observed in 95 patients (17%), severe thrombocytopenia (platelet counts 9 /L) in 93 patients (16.6%) and acute hepatitis in 42 patients (7.5%). Severe thrombocytopenia developed in 57% of patients with plasma leakage and 40.5% of patients with hepatitis. Patients who developed a plasma leakage syndrome were older, mainly male, and reported more often an abdominal pain and a cough. Diarrhea and taking paracetamol >60 mg/kg/day before admission were associated with the development of acute hepatitis. Seven patients died. The mortality rate was 6/95 (6.3%) in patients who developed plasma leakage, 3/42 (7.1%) in patients who developed hepatitis, 5/93 (5.4%) in patients with severe thrombocytopenia, and 3/12 (25%) in the patients who demonstrated together all these severe manifestations. Conclusion Plasma leakage, severe thrombocytopenia and acute hepatitis identified subgroups of adult dengue patients with increased mortality rates. Key symptoms reported by the patients at presentation such as abdominal pain, cough or diarrhea were significantly associated with the development of severe manifestations and should be considered as warning signs.

Background Leptospirosis is a neglected zoonosis affecting mainly tropical and subtropical regions worldwide, particularly South America and the Caribbean. As in many other countries, under-reporting of cases was suspected in the French West Indies because of inadequate access to diagnostic tests for the general population. Methodology/Principal findings In order to estimate the real incidence of leptospirosis in Guadeloupe and Martinique, a study was performed in 2011 using the three prevailing available biological tests for diagnosis: Microscopic Agglutination Test (MAT), IgM ELISA and PCR. The study investigated inpatients and outpatients and used active case ascertainment from data provided by a general practitioners’ sentinel network. The epidemiology of the disease was also described in terms of severity and demographic characteristics. Leptospirosis incidence was estimated at 69.4 (95%CI 47.6–91.1) and 60.6 (95%CI 36.3–85.0) annual cases per 100 000 inhabitants in Guadeloupe and Martinique, respectively, which was 3 and 4 times higher than previous estimations. Conclusion/Significance Inclusion of PCR and IgM ELISA tests for diagnosis of leptospirosis resulted in improved sensitivity in comparison with MAT alone. Our results highlighted the substantial health burden of the disease in these two territories and the importance of access to appropriate laboratory tests. Based on our results, PCR and IgM ELISA tests have now been included in the list of tests reimbursed by the national system of social security insurance in France. Our results also underline the relevance of implementing an integrated strategy for the surveillance, prevention and control of leptospirosis in the French West Indies., Author Summary Leptospirosis is a common disease in tropical regions around the world. It is caused by a bacteria excreted in environmental waters by mammals, especially rodents, through their urine. Leptospirosis has symptoms similar to other tropical diseases, including dengue fever, and early laboratory diagnosis is crucial to provide both appropriate treatments for patients and rapid control measures when an outbreak occurs. In 2011, we undertook a study to determine the incidence of leptospirosis in two territories (Guadeloupe and Martinique) in the French West Indies by establishing a surveillance network and implementing new diagnostic assays in order to ensure an exhaustive diagnostic analysis. We concluded that leptospirosis was previously significantly under-reported in the French West Indies and we recommended: 1- access to these new diagnostic tests for the entire population for a better detection of leptospirosis patients and, 2- the implementation of an integrated surveillance, alert and prevention system for the disease in this region. Our findings had raised the awareness of this neglected disease in the French West Indies and, as another consequence; new diagnostic tests are now reimbursed by the social security insurance in France.

Background Leptospirosis is a potentially life-threatening but curable zoonosis whose prognosis depends on accurate and timely diagnosis. Because of its non-specific clinical presentation, laboratory testing is essential to confirm the diagnosis. Here, we aimed to assess the performance of two enzyme-linked immunosorbent assays (ELISAs) (ELISA Serion and ELISA-Hb Pasteur) and one immunodot (GenBio) using quantitative PCR (qPCR) as gold standard, instead of the traditional microscopic agglutination test, for the diagnosis of acute leptospirosis in an endemic area. Methodology/Principal findings Between January 2011 and December 2012, a total of 122 patients were diagnosed with leptospirosis, as confirmed by qPCR at the University Hospital of Martinique. Among them, 103 had at least one serum sample available for analysis. Performance of each serological assay was evaluated according to days' post onset of symptoms (DPO) and local species diversity (which included L. santarosai, L. interrogans, L. kirschneri, L. borgpetersenii, L. noguchii, and L. kmetyi). Several thresholds were tested to optimize accuracy. When considering the manufacturer's threshold, the sensitivity of ELISA Serion, ELISA-Hb Pasteur and GenBio immunodot was 75%, 67% and 64%, while specificity was 92%, 98% and 100%, respectively. Moreover, the threshold optimization allowed a significant improvement in specificity for the ELISA Serion from 92% to 99% (p, Author summary Leptospirosis is a ubiquitous zoonosis caused by spirochetes. This infection is responsible for a wide range of symptoms mimicking many other diseases. Laboratory tests are thus essential to confirm the diagnosis. Furthermore, earlier diagnosis helps to prevent severe outcomes by a prompt initiation of antibiotic therapy. In early phase, quantitative Polymerase Chain Reaction (qPCR) was proved to be more efficient than the traditional microagglutination test (MAT), which remains the ‘gold standard’ for diagnosis of leptospirosis. However, both tests are seldom available in resource-limited settings, where leptospirosis burden is highest. To find a suitable alternative to qPCR and MAT in the early phase (i.e., within the first 2 weeks) of the disease, we compared 3 serological assays (2 ELISAs plus one immunodot) using sera collected from patients with a qPCR-confirmed diagnosis of leptospirosis. This work reveals high performances for all serological assays after (but not before) 6 days’ post onset of symptoms, regardless of the species studied. Excellent specificity, as found after threshold optimization, suggests that these tests could useful in high prevalence areas.

During the last decade Martinique experienced four dengue epidemics, each characterized by the predominance of 1 or 2 serotypes. In this retrospective database analysis, we investigated the relationship between dengue serotype and disease severity. Data on dengue were collected from 715 patients (male/female ratio 0.87), 14 to 91 years of age (median 35 years) examined in the adult emergency department between 2005 and 2010. In this series, DENV-4 infections more frequently had a milder clinical presentation. The DENV-2 infections were most often secondary infections admitted at the critical phase of dengue illness with signs of plasma leakage. The DENV-1 infections were disabling, particularly in females, and most often led to disease of intermediate severity, without overt plasma leakage. These data were consistent with there being differences in virulence between serotypes, regardless of the host's immune status. However, secondary DENV-2 infections showed an increased risk of plasma leakage.

International audience; Dengue fever has been endemo-epidemic in the whole Region of America. In 2010, Guadeloupe and Martinique experienced historical epidemics, with an estimated attack rate of 10% in two islands. When considering the temporal evolution of epidemiological indicators, an unusual increase in the number of dengue cases could be detected very early. Two main factors might have facilitated the settlement of a viral transmission despite the dry season: a low immunity of the population against the circulating serotype and particular climatic conditions, notably very high temperatures which could have improved both virus and vector efficiency. This unusual situation was considered as a warning sign, and indeed led to major outbreaks in both islands a few weeks later. This event underlines that follow-up of epidemiological indicators is necessary to detect the unusual situations as soon as possible. Furthermore, development of biological and modelling tools should be promoted, as well as integrated management strategies for dengue prevention and control.

International audience; Malaria is endemic in French Guiana. Plasmodium falciparum and Plasmodium vivax are the predominant species responsible and Anopheles darlingi is described as the major vector. In mid-August 2008, an increase in malaria incidence was observed in Saül. A retrospective cohort survey was performed. In vitro susceptibility profiles to antimalarials were determined on P. falciparum isolates. Collections of mosquitoes were organized. The malaria attack rate reached 70.6/100. The risk of malaria increased for people between 40 and 49 years of age, living in a house not subjected to a recent indoor residual insecticide spraying or staying overnight in the surrounding forest. All isolates were susceptible. Anopheles darlingi females and larvae were collected in the village suggesting a local transmission. Our results strongly support a role of illegal mining activities in the emergence of new foci of malaria. Therefore, public health authorities should define policies to fight malaria at a transborder level.

Many wild and domestic animals serve as reservoirs for pathogenic Leptospira strains and contaminate the environment by shedding the organisms in their urine. Humans are usually infected through abraded skin or mucous membrane contact with water contaminated by the urine of animal reservoirs, and less frequently by direct contact with animals or their urine. The mean incubation period is 10 days, with a usual range of 2–20 days. 1 Clinical manifestations are protean and the spectrum of symptoms range from subclinical or mild anicteric febrile illness to acute renal failure. Weil’s disease and respiratory distress syndrome are associated with high mortality. 1 Over the preceding decades, ecotourism and sporting events in tropical and sub-tropical areas have become more popular among travelers and athletes. These recreational activities in tropical areas have served to increase the risk of human exposure to these pathogens and consequently outbreaks of leptospirosis have been reported in these settings. 3, 4

International audience; Population surveys of Culex pipiens quinquefasciatus carried out in 1991 and 1999 were compared with data collected in 1990 before the beginning of the control program against this mosquito. Larval samples collected in 1999 displayed resistance to the four tested insecticides: permethrin, propoxur, temephos, and chlorpyrifos. Temepbos resistance ratio at LC50 (RR50) ranged between 8.1- and 42-fold compared with 2.9- and 4.6-fold in 1990, and chlorpyrifos RR50 ranged between 8.6- and 123-fold compared with 6.4- and 19-fold in 1990. This increased resistance to organophosphorus insecticides was associated with a sharp decrease of susceptible genotypes at two loci (Ester and ace-1), as well as to an allele replacement at the Ester locus.

Introduction – objectifs Les premiers cas autochtones de chikungunya ont ete observes aux Antilles en 12/2013. La Martinique est entree en phase epidemique le 23 janvier 2014. Le vecteur (Aedes aegypti) et le genotype viral (groupe asiatique) sont differents de ceux responsables de l’epidemie de 2005/2006 a la Reunion. L’objectif etait de decrire les formes cliniques observees chez les patients hospitalises dans une population atteinte pour la premiere fois par ce couple vecteur/virus. Materiels et methodes Depuis le 16 decembre 2013 une surveillance des cas confirmes (PCR+) ou probables (IgM+) de chikungunya hospitalises plus de 24 heures a ete mise en place au CHU de Martinique. Les cas ont ete classes en formes communes, inhabituelles non severes, severes (defaillance d’organe), et neonatales severes ou non. Resultats Au 19 fevrier 2014, 88 patients avaient ete hospitalisees plus de 24 heures Le classement des cas a ete effectue chez 28 hommes et 20 femmes âges en mediane de 30 ans, IQR[4,5;71,5]. L’incidence (pour 10 000 hab) globale etait de 1,2, de 18,1 chez les moins de 1 an et de 3,5 chez les plus de 75 ans. Une comorbidite etait notee chez 24 patients. Le classement des cas etait : 32 formes communes, 11 formes inhabituelles (principalement convulsions et atteinte cardiaque), 4 formes severes (1 encephalopathie, 1 defaillance cardiaque, 1 hepatite, 1 thrombopenie), et 1 forme neonatale severe (encephalopathie). La duree mediane d’hospitalisation etait de 3 jours. Un homme de 89 ans, polyvasculaire, est decede d’une pneumonie aigue. Ce deces a ete classe comme indirectement lie au chikungunya. Conclusion Ces donnees montrent une frequence elevee d’hospitalisation des nourrissons et des personnes âgees et confirme l’existence de formes inhabituelles et severes, et le risque de transmission perinatale. Elles seront mises a jour selon l’evolution de l’epidemie

Background Leptospirosis is one of the most important neglected tropical bacterial diseases in Latin America and the Caribbean. However, very little is known about the circulating etiological agents of leptospirosis in this region. In this study, we describe the serological and molecular features of leptospires isolated from 104 leptospirosis patients in Guadeloupe (n = 85) and Martinique (n = 19) and six rats captured in Guadeloupe, between 2004 and 2012. Methods and Findings Strains were studied by serogrouping, PFGE, MLVA, and sequencing 16SrRNA and secY. DNA extracts from blood samples collected from 36 patients in Martinique were also used for molecular typing of leptospires via PCR. Phylogenetic analyses revealed thirteen different genotypes clustered into five main clades that corresponded to the species: L. interrogans, L. kirschneri, L. borgpetersenii, L. noguchi, and L. santarosai. We also identified L. kmetyi in at least two patients with acute leptospirosis. This is the first time, to our knowledge, that this species has been identified in humans. The most prevalent genotypes were associated with L. interrogans serovars Icterohaemorrhagiae and Copenhageni, L. kirschneri serovar Bogvere, and L. borgpetersenii serovar Arborea. We were unable to identify nine strains at the serovar level and comparison of genotyping results to the MLST database revealed new secY alleles. Conclusions The overall serovar distribution in the French West Indies was unique compared to the neighboring islands. Typing of leptospiral isolates also suggested the existence of previously undescribed serovars., Author Summary Leptospirosis is an emerging zoonotic disease caused by infection with pathogenic strains of Leptospira. Isolation of Leptospira strains is rare, making it difficult to assess their distribution worldwide. In this study, we characterized cultures of Leptospira obtained from more than one hundred leptospirosis patients from the French West Indies by serology and various molecular typing methods to identify the strains circulating in this endemic region. Typing of leptospiral isolates showed that causative agents of leptospirosis in the French West Indies are mainly from the serogroups Icterohaemorrhagiae and Ballum, but we also identified new genotypes. We also found that the distribution of the predominant pathogenic leptospiral serovars differed between the Caribbean islands. A better understanding of the epidemiology of leptospirosis will improve our knowledge in the distribution of this emerging neglected tropical disease worldwide. The identification of the circulating etiological agents of leptospirosis in the French West Indies will also help establish appropriate control and prevention measures in this area where the disease is endemic.