Prospective Study of Chikungunya Virus Acute Infection in the Island of La Réunion during the 2005–2006 Outbreak

BACKGROUND:Chikungunya virus (CHIKV) is a recently re-emerged arthropod borne virus responsible for a massive outbreak in the Indian Ocean and India, and extended to Southeast Asia as well as Italy. CHIKV has adapted to Aedes albopictus, an anthropophilic mosquito species widely distributed in Asia, Europe, Africa and America. Our objective was to determine the clinical and biological features of patients at the acute phase of CHIKV infection. METHODS AND FINDINGS:A prospective study enrolled 274 consecutive patients with febrile arthralgia recorded at the Emergency Department of the Groupe Hospitalier Sud-Réunion between March and May 2006. Three groups were defined: one group of 180 viremic patients (positive CHIKV RT-PCR), one group of 34 patients with acute post-viremic infection (negative CHIKV RT-PCR, positive anti-CHIKV IgM and negative IgG), and one group of 46 uninfected patients (negative CHIKV RT-PCR, anti-CHIKV IgM and IgG). Bivariate analyses of clinical and biological features between groups were performed. Patients with CHIKV viremia presented typically with asymmetrical bilateral polyarthralgia (96.5%) affecting the lower (98%) and small joints (74.8%), as well as asthenia (88.6%), headache (70%), digestive trouble (63.3%), myalgia (59%), exanthems (47.8%), conjunctival hyperhemia (23%) and adenopathy (8.9%). Vertigo, cutaneous dysesthesia, pharyngitis and haemorrhages were seldom observed. So far unreported symptoms such as chondrocostal arthralgia (20%), entesopathies (1.6%), talalgia (14%) were also noted. Prurit was less frequent during the viremic than post-viremic phase (13.9% vs. 41.2%; p<0.001), whereas lymphopenia was more frequent (87.6% vs. 39.4%; p<0.001). Others biological abnormalities included leukopenia (38.3%), thrombocytopenia (37.3%), increased ASAT and ALAT blood levels (31.6 and 7.3%, respectively) and hypocalcemia (38.7%). Lymphopenia <1,000/mm(3) was very closely associated with viremic patients (Yule coefficient 0.82, positive predictive value 92.3%). Age under 65 was associated with a benign course, as no patients younger than 65 had to be hospitalized (Yule coefficient 0.78). CONCLUSIONS:The diagnosis of CHIKV infection in acute phase is based on commonly accepted clinical criteria (fever and arthralgia), however clinical and biological diffrences exist in acute phase depending on whether or not the patient is within the viremic phase of the infection

Multidisciplinary Prospective Study of Mother-to-Child Chikungunya Virus Infections on the Island of La Réunion

In a prospective study on the island of La Réunion, Marc Lecuit and colleagues find frequent transmission of Chikungunya virus by viremic mothers giving birth during an outbreak, resulting in serious infant illness

Estimating Chikungunya prevalence in La Réunion Island outbreak by serosurveys: Two methods for two critical times of the epidemic

<p>Abstract</p> <p>Background</p> <p>Chikungunya virus (CHIKV) caused a major two-wave seventeen-month-long outbreak in La Réunion Island in 2005–2006. The aim of this study was to refine clinical estimates provided by a regional surveillance-system using a two-stage serological assessment as gold standard.</p> <p>Methods</p> <p>Two serosurveys were implemented: first, a rapid survey using stored sera of pregnant women, in order to assess the attack rate at the epidemic upsurge (s1, February 2006; n = 888); second, a population-based survey among a random sample of the community, to assess the herd immunity in the post-epidemic era (s2, October 2006; n = 2442). Sera were screened for anti-CHIKV specific antibodies (IgM and IgG in s1, IgG only in s2) using enzyme-linked immunosorbent assays. Seroprevalence rates were compared to clinical estimates of attack rates.</p> <p>Results</p> <p>In s1, 18.2% of the pregnant women were tested positive for CHIKV specific antibodies (13.8% for both IgM and IgG, 4.3% for IgM, 0.1% for IgG only) which provided a congruent estimate with the 16.5% attack rate calculated from the surveillance-system. In s2, the seroprevalence in community was estimated to 38.2% (95% CI, 35.9 to 40.6%). Extrapolations of seroprevalence rates led to estimate, at 143,000 and at 300,000 (95% CI, 283,000 to 320,000), the number of people infected in s1 and in s2, respectively. In comparison, the surveillance-system estimated at 130,000 and 266,000 the number of people infected for the same periods.</p> <p>Conclusion</p> <p>A rapid serosurvey in pregnant women can be helpful to assess the attack rate when large seroprevalence studies cannot be done. On the other hand, a population-based serosurvey is useful to refine the estimate when clinical diagnosis underestimates it. Our findings give valuable insights to assess the herd immunity along the course of epidemics.</p

Evaluation de l'indication de FIV mixte dans le cadre d'échecs répétés d'insémination intra-utérine au CHU de La Réunion (étude rétrospective de deux ans)

BORDEAUX2-BU Santé (330632101) / SudocSudocFranceF

Spermatic Microbiome Characteristics in Infertile Patients: Impact on Sperm Count, Mobility, and Morphology

International audienceThrough sperm alteration, semen microbiota tend to be recognized as a cause of infertility, but due to the limited number of studies focusing on this ecological niche, this hypothesis remains controversial. This study aimed to characterize and compare the bacterial communities of sperm samples from patients undergoing couple infertility treatment at the time of diagnosis. The study was prospective (September 2019 to March 2020), monocentric, and focused on alterations of spermatic parameters: count, motility, and morphology. After the amplification of the 16S rDNA (V1 to V3), libraries (n = 91, including 53 patients with abnormalities) were sequenced using the MiSeq platform(Illumina). After quality control processing using a homemade pipeline (QIIME2 modules), the main genera were: Prevotella, Finegoldia, Pseudomonas, Peptinophilus, Streptococcus, Anaerococcus and Corynebacterium. Restricted diversity was observed in samples from patients with abnormal sperm morphology (α-diversity, p < 0.05), whereas diversity increased in patients with an abnormal sperm count (β-diversity, p < 0.05). The enrichment of the genus Prevotella and Haemophilus was observed in negative sperm culture samples and samples with abnormal counts, respectively (p < 0.05). Microbiotadiffered in their composition according to sperm parameters. Finally, this work highlights the need for the optimization of the management of couples undergoing infertility treatment, possibly by modulating the genital microbiome

Simultaneous detection and quantification of Chikungunya, Dengue and West Nile viruses by multiplex RT-PCR assays and Dengue virus typing using High Resolution Melting

International audienceChikungunya (CHIKV), Dengue (DENV) and West Nile (WNV) viruses are arthropod-borne viruses that are able to emerge or re-emerge in many regions due to climatic changes and increase in travel. Since these viruses produce similar clinical signs it is important for physicians and epidemiologists to differentiate them rapidly. A molecular method was developed for their detection and quantitation in plasma samples and a DENV typing technique were developed. The method consisted in performing two multiplex real-time one-step RT-PCR assays, to detect and quantify the three viruses. Both assays were conducted in a single run, from a single RNA extract containing a unique coextracted and coamplified composite internal control. The quantitation results were close to the best detection thresholds obtained with simplex RT-PCR techniques. The differentiation of DENV types was performed using a High Resolution Melting technique. The assays enable the early diagnosis of the three arboviruses during viremia, including cases of coinfection. The method is rapid, specific and highly sensitive with a potential for clinical diagnosis and epidemiological surveillance. A DENV positive sample can be typed conveniently using the High Resolution Melting technique using the same apparatus

Development of a sensitive real-time reverse transcriptase PCR assay with an internal control to detect and quantify chikungunya virus

International audienceBackground: The chikungunya virus (CHIKV; Alphavirus, Togaviridae) has emerged in the south Western Indian Ocean since early 2005. A major outbreak of CHIKV infection occurred in Reunion Island, where the virus is transmitted by Aedes albopictus mosquitoes. Facing an outbreak of unprecedented magnitude, we developed a rapid, sensitive, and reliable assay for the detection and quantification of CHIKV in plasma samples. Methods: A dual-color TaqMan 1-step reverse transcriptase PCR assay was developed in a LightCycler 2.0 system. A coextd. and coamplified chimerical RNA sequence was used as an internal control (IC) to eliminate false-neg. results. The CHIKV-specific and IC probes were labeled with 6-carboxyfluorescein (530 nm) and the wide span dye DYXL (705 nm), resp., eliminating the need for color compensation. A synthetic RNA was used as an external calibrator for CHIKV abs. quantification. Results: The detection limit was 350 copies/mL (3 copies/capillary). A further improvement to ∼40 copies/mL was obtained by use of a larger vol. of plasma. The assay specificity was confirmed in vitro and in silico. CHIKV in 343 patients was present at viral loads \textgreater108 copies/mL, mainly in newborns and seniors \textgreater60 years old. Long viremic phases of up to 12 days were seen in 6 patients. Conclusions: The assay is rapid, CHIKV-specific, and highly sensitive, and it includes an IC. It proved useful to detect and quantify CHIKV during the Reunion Island epidemic. The assay might be applicable to other CHIKV epidemics, esp. in the Indian subcontinent, where an extensive outbreak is ongoing. [on SciFinder(R)

Enquête de séroprévalence du chikungunya en population générale, La Réunion, hiver austral 2006

International audienceno abstrac

Enquête de séroprévalence du chikungunya en population générale, La Réunion, hiver austral 2006

International audienceno abstrac

Biological parameters.

<p><b><i>Group A1: RT PCR CHIKV positive patients. Group A2: RT PCR CHIKV negative, IgM anti CHIKV positive, IgG anti CHIKV negative patients. Group B: RT PCR CHIKV negative, IgM anti CHIKV negative, IgG anti CHIKV negative patients.</i></b></p><p><b><i>Group A1 vs. Group A2: ^¤¤¤ p<0.001, ^¤¤ p<0.01, ^¤ p<0,05.</i></b></p><p><b><i>Group A1 vs. Group B:</i></b> *** <b><i>p<0.001, ** p<0.01, * p<0,05.</i></b></p><p><b><i>Average, standard deviation, percentage in parenthesis are indicated.</i></b></p><p>^#<b><i>Physiological ranges.</i></b></p