968 resultados para Respiratory Syncytial Virus Infections


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A retrospective study of 2,146 feedlot cattle in 17 feedlot tests from 1988 to 1997 was conducted to determine the impact of bovine respiratory disease (BRD) on veterinary treatment costs, average daily gain, carcass traits, mortality, and net profit. Morbidity caused by BRD was 20.6%. The average cost to treat each case of BRD was $12.39. Mortality rate of calves diagnosed and treated for BRD was 5.9% vs. .35% for those not diagnosed with BRD. Average daily gain differed between treated and non-treated steers during the first 28 days on feed but did not differ from 28 days to harvest. Net profit was $57.48 lower for treated steers. Eighty-two percent of this difference was due to a combination of mortality and treatment costs. Eighteen percent of the net profit difference was due to improved performance and carcass value of the non-treated steers. Data from 496 steers and heifers in nine feedlot tests were used to determine the effects of age, weaning, and use of modified live virus or killed vaccines prior to the test to predict BRD. Younger calves, non-weaned calves, and calves vaccinated with killed vaccines prior to the test had higher BRD morbidity than those that were older, weaned, or vaccinated with modified live virus vaccines, respectively. Treatment regimes that precluded relapse resulting in re-treatment prevented reduced performance and loss of carcass value. Using modified live virus vaccines and weaning calves 30 days prior to shipment reduced the incidence of BRD.

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ABSTRACT: BACKGROUND: In the frame of an eradication program for bovine viral diarrhea (BVD) in Swiss livestock, the question was raised whether free-ranging wildlife could threaten the success of this sanitary measure. Therefore, we conducted serological and virological investigations on BVD virus (BVDV) infections in the four indigenous wild ruminant species (roe deer, red deer, Alpine chamois and Alpine ibex) from 2009 to 2011, and gathered information on interactions between wild and domestic ruminants in an alpine environment by questionnaire survey. RESULTS: Thirty-two sera out of 1'877 (1.7%, 95% confidence interval [CI] 1.2-2.4) were seropositive for BVDV, and a BVDV1 sub genotype h virus was found in a seropositive chamois (0.05%, 95% CI 0.001-0.3). The seropositive animals originated from sub-alpine or alpine regions and significantly more seropositive red deer, chamois and ibex than roe deer were found. There were no statistically significant differences between sampling units, age classes, genders, and sampling years. The obtained prevalences were significantly lower than those documented in livestock, and most positive wild ruminants were found in proximity of domestic outbreaks. Additionally, BVDV seroprevalence in ibex was significantly lower than previously reported from Switzerland. The survey on interspecific interactions revealed that interactions expected to allow BVDV transmission, from physical contacts to non-simultaneous use of the same areas, regularly occur on pastures among all investigated ruminant species. Interactions involving cervids were more often observed with cattle than with small ruminants, chamois were observed with all three domestic species, and ibex interacted mostly with small ruminants. Interactions related to the use of anthropogenic food sources were frequently observed, especially between red deer and cattle in wintertime. CONCLUSIONS: To our knowledge, this is the first report of BVDV RNA isolated from an Alpine chamois. Nevertheless, our results suggest that BVDV infections are only sporadic in Swiss wild ruminants, despite regular occurrence of interactions with potentially infected livestock. Overall, serological, virological and ethological data indicate that wildlife is currently an incidental spill-over host and not a reservoir for BVDV in Switzerland.

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BACKGROUND Partner notification is essential to the comprehensive case management of sexually transmitted infections. Systematic reviews and mathematical modelling can be used to synthesise information about the effects of new interventions to enhance the outcomes of partner notification. OBJECTIVE To study the effectiveness and cost-effectiveness of traditional and new partner notification technologies for curable sexually transmitted infections (STIs). DESIGN Secondary data analysis of clinical audit data; systematic reviews of randomised controlled trials (MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials) published from 1 January 1966 to 31 August 2012 and of studies of health-related quality of life (HRQL) [MEDLINE, EMBASE, ISI Web of Knowledge, NHS Economic Evaluation Database (NHS EED), Database of Abstracts of Reviews of Effects (DARE) and Health Technology Assessment (HTA)] published from 1 January 1980 to 31 December 2011; static models of clinical effectiveness and cost-effectiveness; and dynamic modelling studies to improve parameter estimation and examine effectiveness. SETTING General population and genitourinary medicine clinic attenders. PARTICIPANTS Heterosexual women and men. INTERVENTIONS Traditional partner notification by patient or provider referral, and new partner notification by expedited partner therapy (EPT) or its UK equivalent, accelerated partner therapy (APT). MAIN OUTCOME MEASURES Population prevalence; index case reinfection; and partners treated per index case. RESULTS Enhanced partner therapy reduced reinfection in index cases with curable STIs more than simple patient referral [risk ratio (RR) 0.71; 95% confidence interval (CI) 0.56 to 0.89]. There are no randomised trials of APT. The median number of partners treated for chlamydia per index case in UK clinics was 0.60. The number of partners needed to treat to interrupt transmission of chlamydia was lower for casual than for regular partners. In dynamic model simulations, > 10% of partners are chlamydia positive with look-back periods of up to 18 months. In the presence of a chlamydia screening programme that reduces population prevalence, treatment of current partners achieves most of the additional reduction in prevalence attributable to partner notification. Dynamic model simulations show that cotesting and treatment for chlamydia and gonorrhoea reduce the prevalence of both STIs. APT has a limited additional effect on prevalence but reduces the rate of index case reinfection. Published quality-adjusted life-year (QALY) weights were of insufficient quality to be used in a cost-effectiveness study of partner notification in this project. Using an intermediate outcome of cost per infection diagnosed, doubling the efficacy of partner notification from 0.4 to 0.8 partners treated per index case was more cost-effective than increasing chlamydia screening coverage. CONCLUSIONS There is evidence to support the improved clinical effectiveness of EPT in reducing index case reinfection. In a general heterosexual population, partner notification identifies new infected cases but the impact on chlamydia prevalence is limited. Partner notification to notify casual partners might have a greater impact than for regular partners in genitourinary clinic populations. Recommendations for future research are (1) to conduct randomised controlled trials using biological outcomes of the effectiveness of APT and of methods to increase testing for human immunodeficiency virus (HIV) and STIs after APT; (2) collection of HRQL data should be a priority to determine QALYs associated with the sequelae of curable STIs; and (3) standardised parameter sets for curable STIs should be developed for mathematical models of STI transmission that are used for policy-making. FUNDING The National Institute for Health Research Health Technology Assessment programme.

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BACKGROUND Partner notification (PN) is the process whereby sexual partners of an index patient are informed of their exposure to a sexually transmitted infection (STI) and the need to obtain treatment. For the person (index patient) with a curable STI, PN aims to eradicate infection and prevent re-infection. For sexual partners, PN aims to identify and treat undiagnosed STIs. At the level of sexual networks and populations, the aim of PN is to interrupt chains of STI transmission. For people with viral STI, PN aims to identify undiagnosed infections, which can facilitate access for their sexual partners to treatment and help prevent transmission. OBJECTIVES To assess the effects of different PN strategies in people with STI, including human immunodeficiency virus (HIV) infection. SEARCH METHODS We searched electronic databases (the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE) without language restrictions. We scanned reference lists of potential studies and previous reviews and contacted experts in the field. We searched three trial registries. We conducted the most recent search on 31 August 2012. SELECTION CRITERIA Published or unpublished randomised controlled trials (RCTs) or quasi-RCTs comparing two or more PN strategies. Four main PN strategies were included: patient referral, expedited partner therapy, provider referral and contract referral. Patient referral means that the patient notifies their sexual partners, either with (enhanced patient referral) or without (simple patient referral) additional verbal or written support. In expedited partner therapy, the patient delivers medication or a prescription for medication to their partner(s) without the need for a medical examination of the partner. In provider referral, health service personnel notify the partners. In contract referral, the index patient is encouraged to notify partner, with the understanding that the partners will be contacted if they do not visit the health service by a certain date. DATA COLLECTION AND ANALYSIS We analysed data according to paired partner referral strategies. We organised the comparisons first according to four main PN strategies (1. enhanced patient referral, 2. expedited partner therapy, 3. contract referral, 4. provider referral). We compared each main strategy with simple patient referral and then with each other, if trials were available. For continuous outcome measures, we calculated the mean difference (MD) with 95% confidence intervals (CI). For dichotomous variables, we calculated the risk ratio (RR) with 95% CI. We performed meta-analyses where appropriate. We performed a sensitivity analysis for the primary outcome re-infection rate of the index patient by excluding studies with attrition of greater than 20%. Two review authors independently assessed the risk of bias and extracted data. We contacted study authors for additional information. MAIN RESULTS We included 26 trials (17,578 participants, 9015 women and 8563 men). Five trials were conducted in developing countries. Only two trials were conducted among HIV-positive patients. There was potential for selection bias, owing to the methods of allocation used and of performance bias, owing to the lack of blinding in most included studies. Seven trials had attrition of greater than 20%, increasing the risk of bias.The review found moderate-quality evidence that expedited partner therapy is better than simple patient referral for preventing re-infection of index patients when combining trials of STIs that caused urethritis or cervicitis (6 trials; RR 0.71, 95% CI 0.56 to 0.89, I(2) = 39%). When studies with attrition greater than 20% were excluded, the effect of expedited partner therapy was attenuated (2 trials; RR 0.8, 95% CI 0.62 to 1.04, I(2) = 0%). In trials restricted to index patients with chlamydia, the effect was attenuated (2 trials; RR 0.90, 95% CI 0.60 to 1.35, I(2) = 22%). Expedited partner therapy also increased the number of partners treated per index patient (three trials) when compared with simple patient referral in people with chlamydia or gonorrhoea (MD 0.43, 95% CI 0.28 to 0.58) or trichomonas (MD 0.51, 95% CI 0.35 to 0.67), and people with any STI syndrome (MD 0.5, 95% CI 0.34 to 0.67). Expedited partner therapy was not superior to enhanced patient referral in preventing re-infection (3 trials; RR 0.96, 95% CI 0.60 to 1.53, I(2) = 33%, low-quality evidence). Home sampling kits for partners (four trials) did not result in lower rates of re-infection in the index case (measured in one trial), or higher numbers of partners elicited (three trials), notified (two trials) or treated (one trial) when compared with simple patient referral. There was no consistent evidence for the relative effects of provider, contract or other patient referral methods. In one trial among men with non-gonococcal urethritis, more partners were treated with provider referral than with simple patient referral (MD 0.5, 95% CI 0.37 to 0.63). In one study among people with syphilis, contract referral elicited treatment of more partners than provider referral (MD 2.2, 95% CI 1.95 to 2.45), but the number of partners receiving treatment was the same in both groups. Where measured, there was no statistical evidence of differences in the incidence of adverse effects between PN strategies. AUTHORS' CONCLUSIONS The evidence assessed in this review does not identify a single optimal strategy for PN for any particular STI. When combining trials of STI causing urethritis or cervicitis, expedited partner therapy was more successful than simple patient referral for preventing re-infection of the index patient but was not superior to enhanced patient referral. Expedited partner therapy interventions should include all components that were part of the trial intervention package. There was insufficient evidence to determine the most effective components of an enhanced patient referral strategy. There are too few trials to allow consistent conclusions about the relative effects of provider, contract or other patient referral methods for different STIs. More high-quality RCTs of PN strategies for HIV and syphilis, using biological outcomes, are needed.

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BACKGROUND In 2006, bluetongue virus serotype 8 (BTV-8) was detected for the first time in central Europe. Measures to control the infection in livestock were implemented in Switzerland but the question was raised whether free-ranging wildlife could be a maintenance host for BTV-8. Furthermore Toggenburg orbivirus (TOV), considered as a potential 25th BTV serotype, was detected in 2007 in domestic goats in Switzerland and wild ruminants were considered a potential source of infection. To assess prevalences of BTV-8 and TOV infections in wildlife, we conducted a serological and virological survey in red deer, roe deer, Alpine chamois and Alpine ibex between 2009 and 2011. Because samples originating from wildlife carcasses are often of poor quality, we also documented the influence of hemolysis on test results, and evaluated the usefulness of confirmatory tests. RESULTS Ten out of 1,898 animals (0.5%, 95% confidence interval 0.3-1.0%) had detectable antibodies against BTV-8 and BTV-8 RNA was found in two chamois and one roe deer (0.3%, 0.1-0.8%). Seroprevalence was highest among red deer, and the majority of positive wild animals were sampled close to areas where outbreaks had been reported in livestock. Most samples were hemolytic and the range of the optical density percentage values obtained in the screening test increased with increasing hemolysis. Confirmatory tests significantly increased specificity of the testing procedure and proved to be applicable even on poor quality samples. Nearly all samples confirmed as positive had an optical density percentage value greater than 50% in the ELISA screening. CONCLUSIONS Prevalence of BTV-8 infection was low, and none of the tested animals were positive for TOV. Currently, wild ruminants are apparently not a reservoir for these viruses in Switzerland. However, we report for the first time BTV-8 RNA in Alpine chamois. This animal was found at high altitude and far from a domestic outbreak, which suggests that the virus could spread into/through the Alps. Regarding testing procedures, hemolysis did not significantly affect test results but confirmatory tests proved to be necessary to obtain reliable prevalence estimates. The cut-off value recommended by the manufacturer for the screening test was applicable for wildlife samples.

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BACKGROUND Within the context of an increased epidemiological pressure caused by canine distemper virus (CDV) in Switzerland together with a potential re-emergence of endemic pathogens such as orthopoxviruses (OPXV), dual infections are possible among susceptible species. OBJECTIVE To describe a case of concurrent CDV and OPXV infection in a cat. ANIMAL A 5-year-old, neutered male cat was presented with erythema, crusts and ulcerations around the left eye. High-grade pruritus and a severe conjunctivitis were also present. METHODS Formalin-fixed skin biopsy samples were obtained from lesional skin. Histopathology, CDV immunohistochemistry and CDV and OPXV RT-PCR were performed. RESULTS Histopathological examination showed severe epidermal necrosis extending to the follicular walls and a dermal infiltration, predominantly eosinophilic. Intranuclear and intracytoplasmic eosinophilic inclusion bodies were visible in the wall of affected hair follicles, with occasional formation of syncytia. The RT-PCR revealed the contextual presence of both CDV and OPXV. Scattered cells stained positive for CDV by immunohistochemistry. CONCLUSION AND DISCUSSION Dual infections with CDV and OPXV, although rare, may occur and represent additional differential diagnoses for ulcerative skin lesions in cats.

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An estimated 499 million curable sexually transmitted infections (STIs; gonorrhea, chlamydia, syphilis, and trichomoniasis) occurred globally in 2008. In addition, well over 500 million people are estimated to have a viral STI such as herpes simplex virus type 2 (HSV-2) or human papillomavirus (HPV) at any point in time. STIs result in a large global burden of sexual, reproductive, and maternal-child health consequences, including genital symptoms, pregnancy complications, cancer, infertility, and enhanced HIV transmission, as well as important psychosocial consequences and financial costs. STI control strategies based primarily on behavioral primary prevention and STI case management have had clear successes, but gains have not been universal. Current STI control is hampered or threatened by several behavioral, biological, and implementation challenges, including a large proportion of asymptomatic infections, lack of feasible diagnostic tests globally, antimicrobial resistance, repeat infections, and barriers to intervention access, availability, and scale-up. Vaccines against HPV and hepatitis B virus offer a new paradigm for STI control. Challenges to existing STI prevention efforts provide important reasons for working toward additional STI vaccines. We summarize the global epidemiology of STIs and STI-associated complications, examine challenges to existing STI prevention efforts, and discuss the need for new STI vaccines for future prevention efforts.

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Foxp3+ regulatory T (Treg) cells are essential for the maintenance of immune homeostasis and tolerance. During viral infections, Treg cells can limit the immunopathology resulting from excessive inflammation, yet potentially inhibit effective antiviral T cell responses and promote virus persistence. We report here that the fast-replicating LCMV strain Docile triggers a massive expansion of the Treg population that directly correlates with the size of the virus inoculum and its tendency to establish a chronic, persistent infection. This Treg cell proliferation was greatly enhanced in IL-21R-/- mice and depletion of Treg cells partially rescued defective CD8+ T cell cytokine responses and improved viral clearance in some but not all organs. Notably, IL-21 inhibited Treg cell expansion in a cell intrinsic manner. Moreover, experimental augmentation of Treg cells driven by injection of IL-2/anti-IL-2 immune complexes drastically impaired the functionality of the antiviral T cell response and impeded virus clearance. As a consequence, mice became highly susceptible to chronic infection following exposure to low virus doses. These findings reveal virus-driven Treg cell proliferation as potential evasion strategy that facilitates T cell exhaustion and virus persistence. Furthermore, they suggest that besides its primary function as a direct survival signal for antiviral CD8+ T cells during chronic infections, IL-21 may also indirectly promote CD8+ T cell poly-functionality by restricting the suppressive activity of infection-induced Treg cells.

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In industrial countries, Hepatitis E virus (HEV) transmission to humans is predominantly assumed to be a zoonotic infection. Recently, it has been demonstrated that about 50% of domestic pigs in Germany carry HEV-specific antibodies. However, further investigations concerning the distribution of HEV in different age groups of German domestic pigs, phylogenetic analyses and the viral load in the porcine liver are still pending. Liver samples of all age groups from herds in a pig-dense region in north-western Germany were investigated for the presence and quantity of HEV RNA and subsequently genotyped. Out of 251 liver samples, 34 contained ORF2-specific RNA, whereas 19 samples were positive using ORF1-specific primers, resulting in an overall detection rate of 13.5% and 7.6%, respectively. Especially nursery pigs and growers were tested positive for viral RNA. Furthermore, determination of the HEV copy numbers revealed high replication levels. Up to 10(9) genome copies per g of liver tissue could be detected suggesting a likely high degree of viral spread to the environment. In the HEV-positive liver samples we found no hints for pathohistological changes reflecting the HEV status.The HEV sequences showed marked diversity but could be assigned to HEV genotype 3 without exception. However, by comparing two different genomic fragments, we found indications for infections with two different HEV variants in domestic pigs. Apart from this, the current study confirms the outcome of our recent serological HEV survey and for the first time gives direct proof of HEV infections in the German domestic pig population.

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Lautropia mirabilis, a pleomorphic, motile, gram-negative coccus, has been isolated from the oral cavities of 32 of 60 (53.3%) children infected with human immunodeficiency virus (HIV) and 3 of 25 (12.0%) HIV-uninfected controls; the association of L. mirabilis isolation with HIV infection is significant (P < 0.001). All children in the study, both HIV-infected children and controls, were born to HIV-infected mothers. The presence of this bacterium was not associated with clinical disease in these children. The HIV-infected children with L. mirabilis did not differ from the HIV-infected children without L. mirabilis in immunological status, clinical status, or systemic medications. The role of HIV infection itself or concomitant factors in the establishment of L. mirabilis in the oral cavity remains to be elucidated.

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Primate immunodeficiency viruses, or lentiviruses (HIV-1, HIV-2, and SIV), and hepatitis delta virus (HDV) are RNA viruses characterized by rapid evolution. Infection by primate immunodeficiency viruses usually results in the development of acquired immunodeficiency syndrome (AIDS) in humans and AIDS-like illnesses in Asian macaques. Similarly, hepatitis delta virus infection causes hepatitis and liver cancer in humans. These viruses are heterogeneous within an infected patient and among individuals. Substitution rates in the virus genomes are high and vary in different lineages and among sites. Methods of phylogenetic analysis were applied to study the evolution of primate lentiviruses and the hepatitis delta virus. The following results have been obtained: (1) The substitution rate varies among sites of primate lentivirus genes according to the two parameter gamma distribution, with the shape parameter $\alpha$ being close to 1. (2) Primate immunodeficiency viruses fall into species-specific lineages. Therefore, viral transmissions across primate species are not as frequent as suggested by previous authors. (3) Primate lentiviruses have acquired or lost their pathogenicity several times in the course of evolution. (4) Evidence was provided for multiple infections of a North American patient by distinct HIV-1 strains of the B subtype. (5) Computer simulations indicate that the probability of committing an error in testing HIV transmission depends on the number of virus sequences and their length, the divergence times among sequences, and the model of nucleotide substitution. (6) For future investigations of HIV-1 transmissions, using longer virus sequences and avoiding the use of distant outgroups is recommended. (7) Hepatitis delta virus strains are usually related according to the geographic region of isolation. (8) Evolution of HDV is characterized by the rate of synonymous substitution being lower than the nonsynonymous substitution rate and the rate of evolution of the noncoding region. (9) There is a strong preference for G and C nucleotides at the third codon positions of the HDV coding region. ^

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The immotile cilia syndrome (ICS) comprises a range of congenital defects of the ciliary apparatus most probably transmitted by autosomal recessive inheritance. Because cilia occur mainly in the respiratory and genital tract, the clinical symptoms of ICS are most commonly chronic sinusitis, bronchitis, bronchiectasis and male sterility. The syndrome can be associated with a situs inversus and is then called Kartagener's syndrome. We studied the ciliary ultrastructure in airway biopsies of 5 patients suffering from chronic upper and lower respiratory tract infections. With the single exception of one female patient with confirmed ICS diagnosis (Kartagener's syndrome) the etiology of the recurrent infections was unknown. The following ciliary defects were observed: missing dynein arms, radial spoke defects, missing nexin links, microtubular transpositions, compound cilia, supernumerary, absent, or incomplete microtubules, lack of ciliary orientation and various abnormal patterns of microtubular arrangement. In no instance did a patient show only a single anomaly; defects were always combined. Missing dynein arms, radial spoke defects and microtubular transpositions have frequently been described as lesions specific for ICS. Whenever these lesions were found simultaneously in both the respiratory and genital tracts, their genetic origin cannot be doubted. In our confirmed ICS patient the outer dynein arms were not missing but were reduced in number and length in a large number of cilia. The biopsy was, however, obtained from the heavily infected maxillary sinus and it is known that inflammation can lead to a loss of dynein arms. In the light of our investigations and of a review of the published cases of ciliary anomalies, it is concluded that none of the above defects in itself is specific for ICS. They may all occur as secondary lesions or sporadically as varieties in otherwise healthy subjects. It therefore appears questionable whether ICS can be diagnosed from the ciliary ultrastructure of a single airway biopsy. Assessment of ICS cannot be based simply on the ultrastructural demonstration of a particular ciliary defect, but necessitates additional considerations particularly regarding the origin of the biopsy, the sampling procedures and quantitation of defects. It appears necessary to investigate samples from different parts of the airways and quantitatively analyze the prominent lesions.

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In the developed world, the majority of new and existing hepatitis C virus (HCV) infections occur among people who inject drugs (PWID). The burden of HCV-related liver disease in this group is increasing, but treatment uptake among PWID remains low. Among PWID, there are a number of barriers to care that should be considered and systematically addressed, but these barriers should not exclude PWID from HCV treatment. Furthermore, it has been clearly demonstrated that HCV treatment is safe and effective across a broad range of multidisciplinary healthcare settings. Given the burden of HCV-related disease among PWID, strategies to enhance HCV assessment and treatment in this group are urgently needed. These recommendations demonstrate that treatment among PWID is feasible and provides a framework for HCV assessment, management, and treatment. Further research is needed to evaluate strategies to enhance assessment, adherence, and SVR among PWID, particularly as new treatments for HCV infection become available.

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Bluetongue virus (BTV) is an economically important member of the genus Orbivirus and closely related to African horse sickness virus (AHSV) and Epizootic hemorrhagic disease virus (EHDV). Currently, 26 different serotypes of BTV are known. The virus is transmitted by blood-feeding Culicoides midges and causes disease (bluetongue [BT]) in ruminants. In 2006/2007, BTV serotype 8 (BTV-8) caused widespread outbreaks of BT amongst livestock in Europe, which were eventually controlled employing a conventionally inactivated BTV vaccine. However, this vaccine did not allow the discrimination of infected from vaccinated animals (DIVA) by the commonly used VP7 cELISA. RNA replicon vectors based on propagation-incompetent recombinant vesicular stomatitis virus (VSV) represent a novel vaccine platform that combines the efficacy of live attenuated vaccines with the safety of inactivated vaccines. Our goal was to generate an RNA replicon vaccine for BTV-8, which is safe, efficacious, adaptable to emerging orbivirus infections , and compliant with the DIVA principle. The VP2, VP5, VP3 and VP7 genes encoding the BTV-8 capsid proteins, as well as the non-structural proteins NS1 and NS3 were inserted into a VSV vector genome lacking the essential VSV glycoprotein (G) gene. Infectious virus replicon particles (VRP) were produced on a transgenic helper cell line providing the VSV G protein in trans. Expression of antigens in vitro was analysed by immunofluorescence using monoclonal and polyclonal antibodies. In a pilot study, sheep were immunized with two different VRP-based vaccine candidates, one comprising the BTV-8 antigens VP2, VP5, VP3, VP7, NS1, and NS3, the other one containing antigens VP3, VP7, NS1, and NS3. Control animals received VRPs containing an irrelevant antigen. Virus neutralizing antibodies and protection after BTV-8 challenge were evaluated and compared to animals immunized with the conventionally inactivated vaccine. Full protection was induced only when the two antigens VP2 and VP5 were included in the vaccine. To further evaluate if VP2 alone, a combination of VP2 and VP5 or VP5 alone were necessary for complete protection, we performed a second animal trial. Interestingly, VP2 as well as the combination of VP2 and VP5 but not VP5 alone conferred full protection in terms of neutralizing antibodies, and protection from clinical signs and viremia after BTV-8 challenge. These results show that the VSV replicon system represents a safe, efficacious and DIVA-compliant vaccine against BTV as well as a possible platform for protection against other Orbiviruses, such as AHSV and EHDV.

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Sexually transmitted infections (STI) in HIV-infected people are of increasing concern. We estimated STI prevalence and sexual healthcare seeking behaviour in 224 sexually active HIV-infected people, including men who have sex with men (MSM, n = 112), heterosexual men (n = 65) and women (n = 47). Laboratory-diagnosed bacterial STI were more common in MSM (Chlamydia trachomatis 10.7%; 95% CI 6.2, 18.0%, lymphogranuloma venereum 0.9%; 95% CI 0.1, 6.2%, Neisseria gonorrhoeae 2.7%; 95% CI 0.9, 8.0%, syphilis seroconversion 5.4%; 95% CI 2.0, 11.3%) than heterosexual men (gonorrhoea 1.5%; 95% CI 0.2, 10.3%) or women (no acute infections). Combined rates of laboratory-diagnosed and self-reported bacterial STI in the year before the study were: MSM (27.7%; 95% CI 21.1, 36.7%); heterosexual men (1.5%; 95% CI 0.2, 10.3%); and women (6.4%; 95% CI 2.1, 21.0%). Antibodies to hepatitis C virus were least common in MSM. Antibodies to herpes simplex type 2 virus were least common in heterosexual men. Most MSM, but not heterosexual men or women, agreed that STI testing should be offered every year. In this study, combined rates of bacterial STI in MSM were high; a regular assessment of sexual health would allow those at risk of STI to be offered testing, treatment and partner management.