Tula hantavirus infection in a hospitalised patient, France, June 2015.

We report an infection with Tula virus in June 2015, leading to hospitalisation, in a patient living approximately 60 km east of Paris with no previous remarkable medical history. Clinical symptoms were limited to a fever syndrome with severe headache. The main laboratory findings included thrombocytopenia and elevated transaminase levels. Based on S (small) gene sequence analysis, the strain affecting the patient was closely related to strains detected in Central Europe, especially to a south-east German strain.

Capture-recapture method for estimating annual incidence of imported dengue, France, 2007-2010.

Imported dengue cases pose the public health risk for local circulation in European areas, especially southeast France, where the Aedes mosquito is established. Using a capture-recapture method with Chao's estimator, we estimated the annual incidence of dengue fever and the completeness of existing mandatory notification and laboratory network surveillance systems. During 2007-2010, >8,300 cases with laboratory evidence of recent dengue infection were diagnosed. Of these cases, 4,500 occurred in 2010, coinciding with intense epidemics in the French West Indies. Over this 4-year period, 327 cases occurred in southeast France during the vector activity period. Of these, 234 cases occurred in 2010, most of them potentially viremic. Completeness of the mandatory notification and laboratory network systems were ≈10% and 40%, respectively, but higher in southeast areas during May-November (32% and 69%, respectively). Dengue surveillance systems in France provide complementary information that is essential to the implementation of control measures.

Direct genotyping of Toxoplasma gondii from amniotic fluids based on B1 gene polymorphism using minisequencing analysis.

BACKGROUND: Because some Toxoplasma gondii genotypes may be more virulent in pregnant women, discriminating between them appears valuable. Currently, the main genotyping method is based on single copy microsatellite markers, which limit direct genotyping from amniotic fluids (AFs) to samples with a high parasitic load. We investigated whether the multicopy gene B1 could type the parasite with a higher sensitivity. To estimate the amplifiable DNA present in AFs, we first compared three different PCR assays used for Toxoplasma infection diagnosis: the P30-PCR, targeting the single copy gene P30; the B1-PCR, targeting the repeated B1 gene; and RE-PCR, targeting the repeated element. RESULTS: Of the 1792 AFs analyzed between 2008 and 2011, 73 were RE-PCR positive. Of those, 49 (67.1%) were P30-PCR and B1-PCR positive, and 14 (19.2%) additional AFs were B1-PCR positive only.All 63 BI-positive AFs (France n = 49; overseas n = 14) could be genotyped based on an analysis of eight nucleotide polymorphisms (SNPs) located within the B1 gene. Following high-resolution melting (HRM) analysis, minisequencing was carried out for each of the eight SNPs. DNA from six reference strains was included in the study, and AFs were assigned to one of the three major lineages (Types I, II, and III). In total, 26 genotypes were observed, and the hierarchical clustering distinguished two clades in lineages II (IIa, n = 30 and IIb, n = 4) and III (IIIa n = 23 and IIIb n = 6). There was an overrepresentation of overseas isolates in Clade IIb (4/4, 100%) and Clade IIIa (8/22; 36.4%) (p <0.0001), whereas medical interruption and fetal death were overrepresented in Clade IIb (2/4, 50%) and Clade IIIa (4/23, 17.4%) (p = 0.049). CONCLUSIONS: Although the current genotyping system cannot pretend to replace multilocus typing, we clearly show that targeting the multicopy B1 gene yields a genotyping capacity of AFs around 20% better than when single copy targets are used. The present genotyping method also allows clear identification of genotypes of potential higher virulence.

Significant finding of Bordetella holmesii DNA in nasopharyngeal samples from French patients with suspected pertussis.

Pertussis is routinely diagnosed with real-time PCR based on insertion sequence IS481, which is not specific for Bordetella pertussis. We conducted a retrospective study using real-time PCRs specific for Bordetella pertussis and for Bordetella holmesii on 177 samples positive for IS481 PCR. Bordetella holmesii DNA was detected in 20.3% samples collected from adolescents and adults.

Seroprevalence of varicella in the French population.

OBJECTIVES: To assess the age-specific seroprevalence of varicella in the French population and to explore age-adjusted differences according to gender and geographic region. METHODS: Data were obtained from 1257 randomly selected, frozen serum samples, from subjects 1-30 years of age, that were sent to the Pasteur-Cerba laboratory in November 2003 to January 2004 for the following clinical indications: allergies, respiratory infections, herpes virus infections excluding varicella and endocrinologic tests. IgG concentrations were tested with an indirect enzyme immunoassay. Statistical analyses included use of locally weighted, scatterplot smoothers. RESULTS: Age-specific seroprevalence of varicella increased by >6-fold between 1 and 8 years of age, ie, from 15.0% (95% confidence interval, 8.6-23.5%) for subjects 1-2 years of age to 89.0% (95% confidence interval, 81.0-94.3%) for those 7-8 years of age. The smoothed curve of age-specific seroprevalence suggested that the steepest rate of increase occurred between 1 and 8 years of age, followed by a considerable slowing in the rate of increase, reaching a prevalence of approximately 95% by age 30. Varicella seroprevalence rates were similar for the samples referred for the 4 clinical indications, as follows: allergies, 76.2%; respiratory infections, 74.0%; herpes virus infections excluding varicella, 73.3%; endocrinologic tests, 73.7% (P = 0.84). CONCLUSIONS: Most varicella-zoster virus infections occur during early childhood. Seroprevalence rates reach approximately 50% by 4 years of age and approximately 90% by 8 years. Therefore, the best strategy to reduce the prevalence of wild-type varicella-zoster virus in the French population would be to immunize children 12-18 months of age, as is currently performed in the United States.

Vertebral osteomyelitis due to Bartonella henselae in adults: a report of 2 cases.

We describe 2 adult patients (1 of whom was infected with human immunodeficiency virus) with osteomyelitis due to Bartonella henselae. Diagnosis was established on the basis of direct identification of the microorganism in one case and seroconversion in the other. Both patients recovered completely within 3 months.

Evaluation of the performance of 5 commercialized enzyme immunoassays for the detection of Taenia solium antibodies and for the diagnosis of neurocysticercosis.

This study aimed to evaluate 5 enzyme immunoassays for detecting human antibodies against Taenia solium in human serum and for the diagnosis of neurocysticercosis (NCC): DRG™, RIDASCREEN™, NOVATECH™, CYPRESS™, and IVD™. A collection of 114 reference serum samples were used. All sera were tested both by ELISA and by an immunoblot method (enzyme-linked immunoelectrotransfer blot [EITB]). When compared with EITB, the Ridascreen™ test had the best positive concordance rate (85.1-91.2%) and the NovaLisa test™ showed the optimal negative concordance rate (93.7-95.6%). All tests had a sensitivity under 72% and a specificity above 60%. The best sensitivity was obtained using Ridascreen™ test (71.4%). An optimal specificity was achieved by the NovaLisa test™. T. solium-positive sera all cross-reacted with E. granulosus positive samples. In the commercial assays evaluated here, the most appropriate ELISA test for screening may be the Ridascreen™ assay. Antibody detection seems to be not appropriate for NCC diagnosis because of its overall lack of sensitivity.

Chikungunya infection in travelers.

The largest described outbreak of chikungunya virus has been occurring on the islands of the southwest Indian Ocean since March 2005. We describe the manifestations of chikungunya virus infection in travelers returning from these islands, with focus on skin manifestations.

Enzyme-linked immunosorbent assay specific to Dengue virus type 1 nonstructural protein NS1 reveals circulation of the antigen in the blood during the acute phase of disease in patients experiencing primary or secondary infections.

During flavivirus infection in vitro, nonstructural protein NS1 is released in a host-restricted fashion from infected mammalian cells but not vector-derived insect cells. In order to analyze the biological relevance of NS1 secretion in vivo, we developed a sensitive enzyme-linked immunosorbent assay (ELISA) to detect the protein in the sera of dengue virus-infected patients. The assay was based on serotype 1 NS1-specific mouse and rabbit polyclonal antibody preparations for antigen immunocapture and detection, respectively. With purified dengue virus type 1 NS1 as a protein standard, the sensitivity of our capture ELISA was less than 1 ng/ml. When a panel of patient sera was analyzed, the NS1 antigen was found circulating from the first day after the onset of fever up to day 9, once the clinical phase of the disease is over. The NS1 protein could be detected even when viral RNA was negative in reverse transcriptase-PCR or in the presence of immunoglobulin M antibodies. NS1 circulation levels varied among individuals during the course of the disease, ranging from several nanograms per milliliter to several micrograms per milliliter, and peaked in one case at 50 microg/ml of serum. Interestingly, NS1 concentrations did not differ significantly in serum specimens obtained from patients experiencing primary or secondary dengue virus infections. These findings indicate that NS1 protein detection may allow early diagnosis of infection. Furthermore, NS1 circulation in the bloodstream of patients during the clinical phase of the disease suggests a contribution of the nonstructural protein to dengue virus pathogenesis.