In Vitro Growth, Receptor Usage and Pathogenesis of Feline Morbillivirus in the Natural Host.

Feline morbillivirus (FeMV) is a recently discovered virus belonging to the genus Morbillivirus of the virus family Paramyxoviridae. Often, the virus has been detected in urine of cats with a history of urinary disease and has a worldwide distribution. Currently, it is unclear which receptor the virus uses to enter the target cells. Furthermore, many aspects of FeMV biology in vivo, including tissue tropism, pathogenesis, and virus excretion in the natural host remain unclear. In this study we analyzed the replication of FeMV in various cell lines. Secondly, we tested if the presence of feline SLAMF1 (Signaling Lymphocytic Activation Molecule family 1/CD150, principal entry receptor for other members of the Morbillivirus genus) improved FeMV replication efficiency in vitro. Finally, to elucidate in vivo biology in cats, as a natural host for FeMV, we experimentally infected a group of cats and monitored clinical symptoms, viremia, and excretion of the virus during the course of 56 days. Our study showed that FeMV shares some features with other morbilliviruses like the use of the SLAMF1 receptor. For the first time, experimental infection of SPF cats showed that FeMV does not induce an acute clinical disease like other morbilliviruses but can induce lesions in the kidneys, including tubulointerstitial nephritis. Further investigations are needed to confirm the site and dynamics of replication of FeMV in the urinary tract and the longer-term impact of FeMV-induced lesions on the renal function. Whether FeMV infection can result in chronic kidney disease will require the monitoring of cats over a longer period.

Protection from Hendra virus infection with Canarypox recombinant vaccine.

Hendra virus (HeV) is an emerging zoonotic pathogen, which causes severe respiratory illness and encephalitis in humans and horses. Since its first appearance in 1994, spillovers of HeV from its natural reservoir fruit bats occur on almost an annual basis. The high mortality rate in both humans and horses and the wide-ranging reservoir distribution are making HeV a serious public health problem, especially for people exposed to sick horses. This study has aimed to develop an efficient low-cost HeV vaccine for horses based on Canarypox recombinant vector expressing HeV glycoproteins, attachment glycoprotein (G) and fusion protein (F). This vaccine was used to immunise hamsters and then challenged intraperitoneally with HeV 3 weeks later. The higher tested dose of the vaccine efficiently prevented oropharyngeal virus shedding and protected animals from clinical disease and virus-induced mortality. Vaccine induced generation of seroneutralising antibodies and prevented virus-induced histopathological changes and a production of viral RNA and antigens in animal tissues. Interestingly, some vaccinated animals, including those immunised at a lower dose, were protected in the absence of detectable specific antibodies, suggesting the induction of an efficient virus-specific cellular immunity. Finally, ponies immunised using the same vaccination protocol as hamsters developed strong seroneutralising titres against both HeV and closely related Nipah virus, indicating that this vaccine may have the ability to induce cross-protection against Henipavirus infection. These data suggest that Canarypox-based vectors encoding for HeV glycoproteins present very promising new vaccine candidate to prevent infection and shedding of the highly lethal HeV.

Portuguese man-of-war (Physalia physalis) envenomation on the Aquitaine Coast of France: an emerging health risk.

CONTEXT: The Portuguese man-o-war is a cnidaria classically found in tropical waters. It can cause serious and even life-threatening envenomation in swimmers, surfers and seafarers. Presence of the Atlantic species Physalia physalis has long been reported in European coastal waters but was always an exceptional event. OBJECTIVE: To describe the experience of the Bordeaux Poison centre about Physalia stings since the first collective episode reported in 2008. METHODS: Clinical retrospective description of cases series of Physalia envenomations reported to the local poison centre from 2008 to 2011 inclusive. RESULTS: In the summer of 2008, multiple-case incident involving 40 victims were recorded on the same day on one beach in the Southern French Atlantic coast. The following year in 2009, no envenomation cases were reported in the same area, but in the next 2 years, numerous man-of-war envenomations occurred along the Aquitaine coast, that is, 154 cases in 2010 and 885 in 2011. Portuguese man-o-war stings led to severe manifestations with 15-20% of patients suffering of general symptoms that were sometimes severe enough to be considered as potentially life-threatening (8% of patients in 2011, most frequent signs: muscle pain and cramps with fasciculations, confusion and drowsiness, fainting, respiratory distress). No deaths due to Portuguese man-o-war envenomation were reported over the 4-year study period. CONCLUSION: The results suggest that national multidisciplinary summer surveillance program in the Aquitaine coast is required in order to provide alerts to the public, to better identify patients at risk for developing severe clinical symptoms, and hopefully to improve quality of health care.