Jonas Johansson Wensman

Presence of antibodies to Schmallenberg virus in a dog in Sweden

Schmallenberg virus (SBV) is an orthobunyavirus first discovered in November 2011 in German cattle ([1][1]). Since the first descriptions in Germany, SBV has spread all over the European continent, including Sweden ([2][2], [3][3]). SBV is an arthropod-borne (arbo)virus primarily spread by biting

Partial genetic characterization of peste des petits ruminants virus from goats in northern and eastern Tanzania.

Peste des petits ruminants (PPR) is an acute viral disease of small ruminants. The disease was first reported in Tanzania in 2008 when it was confined to the Northern Zone districts bordering Kenya. The present study was carried out to confirm the presence of PPR virus (PPRV) in Tanzania and to establish their phylogenetic relationships. Samples (oculonasal swabs, tissues and whole blood) were obtained from live goats with clinical presentation suggestive of PPR and goats that died naturally in Ngorongoro (Northern Tanzania) and Mvomero (Eastern Tanzania) districts. The clinical signs observed in goats suspected with PPR included fever, dullness, diarrhea, lacrimation, matting of eye lids, purulent oculonasal discharges, cutaneous nodules, erosions on the soft palate and gums and labored breathing. Post mortem findings included pneumonia, congestion of the intestines, and hemorrhages in lymph nodes associated with the respiratory and gastrointestinal systems. PPRV was detected in 21 out of 71 tested animals using primers targeting the nucleoprotein (N) gene. Phylogenetic analysis, based on the N gene, indicated that PPRV obtained from Northern and Eastern Tanzania clustered with PPRV strains of Lineage III, together with PPRV from Sudan and Ethiopia. The findings of this study indicate that there are active PPRV infections in Northern and Eastern Tanzania, suggesting risks for potential spread of PPR in the rest of Tanzania.

Genetic analysis of peste des petits ruminants virus from Pakistan

BackgroundPeste des petits ruminants (PPR) is an endemic and highly contagious disease in small ruminants of Pakistan. Despite the fact that an effective vaccine is available, outbreaks are regularly occurring in the country. Thus so far, the diagnosis has primarily been made based on clinical outcome or serology. This study was carried out to characterize PPRV from an emerging wave of outbreaks from Punjab, Pakistan.ResultsA total of 32 blood samples from five different flocks were tested with real-time PCR for the presence of PPRV genome. The samples detected positive in real-time PCR (n = 17) were subjected to conventional PCR for the amplification of the nucleoprotein (N) gene. Phylogenetic analysis of the sequenced N genes (n = 8) indicated the grouping of all the sequences in lineage IV along with PPRV strains from Asian and Middle East. However, interestingly sequences were divided into two groups. One group of viruses (n = 7) clustered with previously characterized Pakistani isolates whereas one strain of PPRV was distinct and clustered with Saudi Arabian and Iranian strains of PPRV.ConclusionsResults demonstrated in this study expanded the information on the genetic nature of different PPRV population circulating in small ruminants. Such information is essential to understand genetic nature of PPRV strains throughout the country. Proper understanding of these viruses will help to devise control strategies in PPRV endemic countries such as Pakistan.

Expression of interferon gamma in the brain of cats with natural Borna disease virus infection

Borna disease virus (BDV) is a neurotropic, negative-stranded RNA virus, which causes a non-suppurative meningoencephalomyelitis in a wide range of animals. In cats, BDV infection leads to staggering disease. In spite of a vigorous immune response the virus persists in the central nervous system (CNS) in both experimentally and naturally infected animals. Since the CNS is vulnerable to cytotoxic effects mediated via NK-cells and cytotoxic T-cells, other non-cytolytic mechanisms such as the interferon (IFN) system is favourable for viral clearance. In this study, IFN-γ expression in the brain of cats with clinical signs of staggering disease (N=12) was compared to the expression in cats with no signs of this disease (N=7) by quantitative RT-PCR. The IFN-γ expression was normalised against the expression of three reference genes (HPRT, RPS7, YWHAZ). Cats with staggering disease had significantly higher expression of IFN-γ compared to the control cats (p-value ≤ 0.001). There was no significant difference of the IFN-γ expression in BDV-positive (N=7) and -negative (N=5) cats having clinical signs of staggering disease. However, as BDV-RNA still could be detected, despite an intense IFN-γ expression, BDV needs to have mechanisms to evade this antiviral immune response of the host, to be able to persist.

Experiences of Borna Disease Virus infection in Sweden

In the early 1970s a fatal neurological disorder in cats was reported in the areas around Lake Mälaren in central Sweden. The major signs were hind-leg ataxia, as well as absence or marked decrease in postural reactions and in some cases behavioural changes. The pathology of the disorder was characterized as a non-suppurative meningoencephalomyelitis, but the etiology was not determined. Almost twenty years later, the disorder now known as staggering disease (SD), was further characterized both clinically and pathologically. The same histopathological picture was seen as in the previous study, with inflammatory nodules, neuronal degeneration and perivascular cuffs mainly consisting of lymphocytes. The most severe inflammatory changes were seen in the grey matter of the brain stem, basal ganglia and hippocampus. Clinically the same major neurological signs were seen. Although the cats were examined for several known infectious agents causing central nervous system (CNS) disturbances, no etiological cause of SD was determined.

Evaluation of Risk Factors for Peste des Petits Ruminants Virus in Sheep and Goats at the Wildlife-Livestock Interface in Punjab Province, Pakistan.

Peste des petits ruminants virus (PPRV) is causing infectious disease with high morbidity and mortality rate in domestic and wild small ruminants of Pakistan with valuable economical losses. The present study was carried out to investigate risk factors of PPRV in domestic small ruminants which were present in the vicinity of wildlife parks. A total of 265 sera samples (27 wild ruminants and 238 domesticated small ruminants) from apparently healthy animals from two different wildlife parks were collected and analysed for PPRV antibodies. Also, 20 nasal swabs from domestic small ruminants showing respiratory signs were collected to check for presence of PPRV antigen. Competitive ELISA revealed highest proportions of anti-PPRV antibodies in domestic small ruminants around the Wildlife Park at Lahore (35%) as compared to Faisalabad (13%), with no existence of PPRV antibodies in tested serum of wild ruminants at these parks. Higher seropositivity was observed in females (25.6%) than in males (5.1%) and in goats (34.5%) compared to sheep (11.2%). The results of N-gene based RT-PCR highlight the absence of PPRV due to lack of current PPR outbreak in the region during study period. Even though grazing was not a significant risk factor, there is still a possibility of wildlife-livestock interactions for feed and water reservoirs, resulting in spillover of PPR to wildlife. Keeping in view the high seropositivity and risk of PPR, vaccination should be adopted to avoid circulation of PPRV among wild and domestic small ruminants (sheep and goats).

A study of Rift Valley fever virus in Morogoro and Arusha regions of Tanzania - serology and farmers’ perceptions

Introduction Rift Valley fever (RVF) is a zoonosis primarily affecting ruminants, resulting in epidemic abortions, fever, nasal and ocular discharges, haemorrhagic diarrhoea, and a high mortality rate among young animals. Rift Valley fever virus (RVFV) is an arthropod-borne RNA virus occurring in epizootic periods associated with heavy rainfall. The last outbreak of RVF in Tanzania was in 2006–2007, resulting in severe economic losses and impaired food security due to greater number of deaths of livestock. The aim of this study was to investigate the presence of antibodies against RVFV in sheep and goats in two different regions of Tanzania during an inter-epidemic period (IEP). In addition, the perception of important diseases among livestock keepers was assessed. Material and methods A cross-sectional serological survey was conducted in three purposively selected districts in Arusha and Morogoro regions of Tanzania. Serum samples from 354 sheep and goats were analysed in a commercial RVFV competitive ELISA. At the sampling missions, a questionnaire was used to estimate the socio-economic impact of infectious diseases. Results and discussion In total, 8.2% of the analysed samples were seropositive to RVF, and most seropositive animals were younger than 7 years, indicating a continuous circulation of RVFV in the two regions. None of the livestock keepers mentioned RVF as an important livestock disease. Conclusions This study confirms that RVFV is circulating at low levels in small ruminants during IEPs. In spite of recurring RVF outbreaks in Tanzania, livestock keepers seem to have a low awareness of the disease, making them poorly prepared and thus more vulnerable to future RVF outbreaks.

The X proteins of bornaviruses interfere with type I interferon signalling

Borna disease virus (BDV) is a neurotropic, negative-stranded RNA virus causing persistent infection and progressive neurological disorders in a wide range of warm-blooded animals. The role of the small non-structural X protein in viral pathogenesis is not completely understood. Here we investigated whether the X protein of BDV and avian bornavirus (ABV) interferes with the type I interferon (IFN) system, similar to other non-structural proteins of negative-stranded RNA viruses. In luciferase reporter assays, we found that the X protein of various bornaviruses interfered with the type I IFN system at all checkpoints investigated, in contrast to previously reported findings, resulting in reduced type I IFN secretion.

Borna disease virus infection in cats

Bornaviruses are known to cause neurological disorders in a number of animal species. Avian Bornavirus (ABV) causes proventricular dilatation disease (PDD) in birds and Borna disease virus (BDV) causes Borna disease in horses and sheep. BDV also causes staggering disease in cats, characterised by ataxia, behavioural changes and loss of postural reactions. BDV-infection markers in cats have been reported throughout the world. This review summarizes the current knowledge of Borna disease viruses in cats, including etiological agent, clinical signs, pathogenesis, epidemiology and diagnostics, with comparisons to Bornavirus infections in other species.

Markers of Borna disease virus infection in cats with staggering disease

Borna disease virus (BDV) is a RNA-virus causing neurological disorders in a wide range of mammals. In cats, BDV infection may cause staggering disease. Presently, staggering disease is a tentative clinical diagnosis, only confirmed at necropsy. In this study, cats with staggering disease were investigated to study markers of BDV infection aiming for improvement of current diagnostics. Nineteen cats fulfilled the inclusion criteria based on neurological signs and pathological findings. In 17/19 cats, BDV infection markers (BDV-specific antibodies and/or BDV-RNA) were found, and antibodies in serum (13/16, 81%) were the most common marker. BDV-RNA was found in 11/19 cats (58%). In a reference population without neurological signs, 4/25 cats were seropositive (16%). The clinical history and neurological signs in combination with presence of BDV infection markers, where serology and rRT-PCR on blood can be helpful tools, improve the diagnostic accuracy in the living cat.