Hantavirus taxonomy and situation in France

Hantaviruses are viruses belonging to the family Bunyaviridae. Twenty-three species are officially reported but more than 70 taxa are not yet classified. Each virus taxa is usually associated with one natural host species, including rodents and soricomorphs. Sequences of new hantaviruses have also been recently detected in bats. Transmission of the virus between individuals occurred through direct contact or through inhalation of excretions or secretions. Using these routes, some rodents-borne hantaviruses can be transmitted to humans and cause a hemorrhagic fever with renal syndrome (HFRS) or a cardiopulmonary syndrome (HPS). There is no specific treatment of the diseases. Three of these zoonotic viruses have been detected in Metropolitan France. Puumala virus, hosted by Myodes glareolus, is medically the most important. About 1000 HFRS have been detected for the last ten years in the North-East part of France. Outbreaks occur in this endemic area every two or three years. A peak in the detection of cases is observed by the end of spring. Adults, mainly men, are concerned. Wood handling, opening and cleaning of unused building, forest activities are occupations favoring the exposure to the virus. Seoul virus has been detected in its reservoir Rattus norvegicus in Lyon. Human cases have been serologically suspected but the first virological evidence of a human case occurred only in 2012. Tula virus has been detected in its natural host Microtus arvalis in Jura. No human case has been detected. Lastly Maripa virus has been described for the first time in French Guiana. This virus has been responsible for three HPS cases, including two fatal cases. Thirty years after the first detection of PUUV human cases, a lot remains to discover in the circulation of these viruses in the countryLes hantavirus sont des virus appartenant à la famille des Bunyaviridae. Vingt-trois espèces sont officiellement rapportées mais plus de 70 taxons sont en attente de classification. Chaque taxon a pour réservoir une espèce de rongeurs ou d’insectivores (Ordre Soricomorpha). Des séquences de nouveaux hantavirus ont été très récemment détectées chez des chauves-souris. Certains des hantavirus associés aux rongeurs sont zoonotiques La transmission s’effectue généralement par l’inhalation d’aérosols d’excrétats ou de sécrétions de rongeurs contaminés. Ces virus sont alors responsables d’une fièvre hémorragique avec syndrome rénal (FHSR) ou d’un syndrome cardio pulmonaire (SCP). Le traitement de ces maladies est symptomatique. Trois de ces virus zoonotiques ont été détectés en France métropolitaine. Le virus Puumala, associé au rongeur Myodes glareolus, a la plus grande importance médicale. Environ un millier de cas de FHSR ont été détectés au cours des dix dernières années, dans le quart Nord-Est de la France qui est la zone d’endémie. Des épidémies sont observées tous les deux à trois ans avec un pic survenant généralement à la fin du printemps. Les adultes et particulièrement les hommes sont les plus atteints. La manipulation du bois, l’ouverture et le nettoyage de local non utilisé, les activités en forêt sont des occupations favorisant l’exposition. Le virus Seoul a été détecté chez Rattus norvegicus à Lyon. Des cas humains étaient suspectés mais la preuve virologique d’un premier cas de FHSR due à ce virus n’a été faite qu’en 2012. Le virus Tula a été détecté chez son hôte Microtus arvalis dans le Jura. Aucun cas humain n’a pour le moment été observé. Enfin, le virus Maripa a été décrit pour la première fois en Guyane française. Il a été responsable de trois cas de SCP dont deux mortels. Trente ans après la détection des premiers cas humains d’infection par un hantavirus en France, il reste encore beaucoup à découvrir sur la circulation de ces virus dans le pay

Serologic Evidence of Lyssavirus Infection in Bats, Cambodia

In Cambodia, 1,303 bats of 16 species were tested for lyssavirus. No lyssavirus nucleocapsid was detected in 1,283 brains tested by immunofluorescence assay. Antibodies against lyssaviruses were detected by enzyme-linked immunosorbent assay in 144 (14.7%) of 981 serum samples. Thirty of 187 serum samples contained neutralizing antibodies against different lyssaviruses

Laboratory Surveillance of Rabies in Humans, Domestic Animals, and Bats in Madagascar from 2005 to 2010

Background. Rabies virus (RABV) has circulated in Madagascar at least since the 19th century. Objectives. To assess the circulation of lyssavirus in the island from 2005 to 2010. Materials and Methods. Animal (including bats) and human samples were tested for RABV and other lyssavirus using antigen, ribonucleic acid (RNA), and antibodies detection and virus isolation. Results. Half of the 437 domestic or tame wild terrestrial mammal brains tested were found RABV antigen positive, including 54% of the 341 dogs tested. This percentage ranged from 26% to 75% across the period. Nine of the 10 suspected human cases tested were laboratory confirmed. RABV circulation was confirmed in 34 of the 38 districts sampled. No lyssavirus RNA was detected in 1983 bats specimens. Nevertheless, antibodies against Lagos bat virus were detected in the sera of 12 among 50 Eidolon dupreanum specimens sampled. Conclusion. More than a century after the introduction of the vaccine, rabies still remains endemic in Madagascar

Henipavirus and Tioman Virus Antibodies in Pteropodid Bats, Madagascar

Specimens were obtained from the 3 Malagasy fruit bats, Pteropus rufus, Eidolon dupreanum, and Rousettus madagascariensis. Antibodies against Nipah, Hendra, and Tioman viruses were detected by immunoassay in 23 and by serum neutralization tests in 3 of 427 serum samples, which suggests that related viruses have circulated in Madagascar

Wild Rats, Laboratory Rats, Pet Rats: Global Seoul Hantavirus Disease Revisited.

Recent reports from Europe and the USA described Seoul orthohantavirus infection in pet rats and their breeders/owners, suggesting the potential emergence of a "new" public health problem. Wild and laboratory rat-induced Seoul infections have, however, been described since the early eighties, due to the omnipresence of the rodent reservoir, the brown rat Rattus norvegicus. Recent studies showed no fundamental differences between the pathogenicity and phylogeny of pet rat-induced Seoul orthohantaviruses and their formerly described wild or laboratory rat counterparts. The paucity of diagnosed Seoul virus-induced disease in the West is in striking contrast to the thousands of cases recorded since the 1980s in the Far East, particularly in China. This review of four continents (Asia, Europe, America, and Africa) puts this "emerging infection" into a historical perspective, concluding there is an urgent need for greater medical awareness of Seoul virus-induced human pathology in many parts of the world Given the mostly milder and atypical clinical presentation, sometimes even with preserved normal kidney function, the importance of simple but repeated urine examination is stressed, since initial but transient proteinuria and microhematuria are rarely lacking

Outbreak of Dengue and Chikungunya Fevers, Toamasina, Madagascar, 2006

An outbreak of dengue-like syndrome occurred in Toamasina from January through March 2006. Dengue type l or chikungunya viruses were detected in 38 of 55 patients sampled. Aedes albopictus was the only potential vector collected. Of 4,242 randomly selected representative residents interviewed retrospectively, 67.5% reported a dengue-like syndrome during this period

Fast, sensitive and specific detection of Thailand orthohantavirus and its variants using one-step real-time reverse-transcription polymerase chain reaction assay

Funding: This study was supported by the Programme Transversal de Recherche (PTR 505) funded by the Institut Pasteur International Network. V.R. was also supported though Girard’s fellowship undergraduate program from the Institut Pasteur de Madagascar and traineeship grants Calmette and Yersin program from the Institut Pasteur International Network. Acknowledgements: We would like to express our gratitude to the staff of the Plague Central Laboratory Unit, Institut Pasteur de Madagascar: Minoarisoa Rajerison, Fehivola Mandanirina Andriamiarimanana, and Soanandrasana Rahelinirina for conducting the field work and for providing samplesPeer reviewedPublisher PD

Suppression of HIV-1 replication by microRNA effectors

The rate of HIV-1 gene expression is a key step that determines the kinetics of virus spread and AIDS progression. Viral entry and gene expression were described to be the key determinants for cell permissiveness to HIV. Recent reports highlighted the involvement of miRNA in regulating HIV-1 replication post-transcriptionally. In this study we explored the role of cellular factors required for miRNA-mediated mRNA translational inhibition in regulating HIV-1 gene expression. Here we show that HIV-1 mRNAs associate and co-localize with components of the RNA Induced Silencing Complex (RISC), and we characterize some of the proteins required for miRNA-mediated silencing (miRNA effectors). RCK/p54, GW182, LSm-1 and XRN1 negatively regulate HIV-1 gene expression by preventing viral mRNA association with polysomes. Interestingly, knockdown of RCK/p54 or DGCR8 resulted in virus reactivation in PBMCs isolated from HIV infected patients treated with suppressive HAART

Nipah Virus in Lyle's Flying Foxes, Cambodia

We conducted a survey in Cambodia in 2000 on henipavirus infection among several bat species, including flying foxes, and persons exposed to these animals. Among 1,072 bat serum samples tested by enzyme-linked immunosorbent assay, antibodies reactive to Nipah virus (NiV) antigen were detected only in Pteropus lylei species; Cynopterus sphinx, Hipposideros larvatus, Scotophilus kuhlii, Chaerephon plicata, Taphozous melanopogon, and T. theobaldi species were negative. Seroneutralization applied on a subset of 156 serum samples confirmed these results. None of the 8 human serum samples was NiV seropositive with the seroneutralization test. One virus isolate exhibiting cytopathic effect with syncytia was obtained from 769 urine samples collected at roosts of P. lylei specimens. Partial molecular characterization of this isolate demonstrated that it was closely related to NiV. These results strengthen the hypothesis that flying foxes could be the natural host of NiV. Surveillance of human cases should be implemented

Rift Valley Fever during Rainy Seasons, Madagascar, 2008 and 2009

The virus reemerged during an outbreak in Madagascar in 2008