Human bocavirus (HBoV) was discovered in 2005 and is associated with respiratory tract symptoms in young children. Three additional members of the genus Bocavirus, HBoV2, -3, and -4, were discovered ...recently from fecal specimens, and early results indicate an association between HBoV2 and gastrointestinal disease. In this study, we present an undifferentiating multiplex real-time quantitative PCR assay for the detection of these novel viruses. Differentiation of the individual bocavirus species can be subsequently achieved with corresponding singleplex PCRs or by sequencing. Both multiplex and singleplex assays were consistently able to detect less-than or equal to10 copies of HBoV1 to -4 plasmid templates/reaction, with dynamic quantification ranges of 8 logs and 97% to 102% average reaction efficiencies. These new assays were used to screen stool samples from 250 Finnish patients (median age, 40 years) that had been sent for diagnosis of gastrointestinal infection. Four patients (1.6%; median age, 1.1 years) were reproducibly positive for HBoV2, and one patient (0.4%; 18 years of age) was reproducibly positive for HBoV3. The viral DNA loads varied from <10³ to 10⁹ copies/ml of stool extract. None of the stool samples harbored HBoV1 or HBoV4. The highly conserved sequence of the hydrolysis probe used in this assay may provide a flexible future platform for the quantification of additional, hitherto-unknown human bocaviruses that might later be discovered. Our results support earlier findings that HBoV2 is a relatively common pathogen in the stools of diarrheic young children, yet does not often occur in the stools of adults.
The objective of this study was to investigate, by partial sequencing of VP2 protein, the variability of CPV detected in 37 fecal samples collected from vaccinated puppies with enteritis. ...Laboratorial diagnosis of CPV was confirmed by HA/HI and PCR and, for sequencing analyses, two different regions of the VP2 gene were amplified by PCR. From 1995 to 2004, all strains were characterized as CPV-2a. After that, both CPV-2a and CPV-2b were detected. All CPV-2a showed a non-synonymous mutation in the residue 297 (Ser
→
Ala). A synonymous substitution at the AA 574 was also observed in 15/37 samples. Our findings indicate that the cases of vaccine failure are most likely not associated to the mutations detected in the sequenced regions. However, the monitoring of genotyping mutations that led to new CPV strains is essential to determinate if current vaccines will keep providing protection against all new future variants.
Infectious disease threats are increasingly recognized as a major contributor to mortality in wild populations of African wild dog (
AWD). Canine distemper virus (CDV) infection has been implicated ...as a cause of pack mortality in both captive and wild AWD populations. Ten animals were vaccinated with Recombitek
C3, a vaccine containing a recombinant CDV, and modified live canine parvovirus (CPV) and adenovirus-2 components, at 8, 12, and 16 wk of age. Half of the pups received the vaccine IM and the other half SC. All ten pups had a positive serological response to CDV after the second vaccination, which decreased or stagnated after the third vaccination. Half of the pups had CDV titers ≥32 at 20 wk of age. Titers to CPV were high in all pups prior to vaccination and dropped precipitously over the course of the vaccine series. At the last sampling period, only 50% of the pups had measurable CPV titers. An initially higher titer was seen for CDV in the IM administration group; however, this was not significant at later time points. Vaccination with Recombitek C3 appears to be safe and effected a sustained serological response to CDV in AWD.
Parvovirus infects a wide variety of species. The rapid evolution, environmental resistance, high dose of viral shedding, and interspecies transmission have made some strains of parvovirus infection ...difficult to control within domestic animal populations. Some parvoviruses in companion animals, such as canine parvovirus (CPV) 1 and feline parvovirus, have demonstrated minimal evolution over time. In contrast, CPV 2 has shown wide adaptability with rapid evolution and frequent mutations. This article briefly discusses these three diseases, with emphasis on virus evolution and the challenges to protecting susceptible companion animal populations.
Cyclic peptide nanotubes (cPNTs) formed from the spontaneous beta-sheet stacking of peptide rings may serve as a safe and effective oral delivery vehicle/adjuvant for DNA vaccines.
In this study, we ...sought to determine if a DNA vaccine expressing the VP2 protein of goose parvovirus, adjuvanted with cPNTs, may elicit virus-specific antibody response through oral vaccination.
Forty 20-day-old Muscovy ducks were randomly assigned to two groups of 20 ducks each and vaccinated. Ducks were orally vaccinated (Day 0) and boosted (Day 1 and Day 2) or were mock-vaccinated with saline as the negative control. For immunohistochemical staining, the primary antibody used comprised a rabbit anti-GPV antibody, and the secondary antibody was a goat anti-rabbit antibody. Goat-anti-mouse-IgG was used as a tertiary antibody. IgG and IgA antibody titers in serum were analyzed by the GPV virus-coated ELISA. For IgA antibody analysis, intestine lavage was harvested too.
A DNA vaccine, coated with cPNTs, can induce a significant antibody response in ducklings. Immunohistochemical staining of tissues from vaccinated ducklings showed that VP2 proteins can be detected in the intestines and livers for up to six weeks, confirming the antigen expression by the DNA vaccine. Antibody analysis found that this vaccine formulation was very efficient at inducing IgA antibodies in the serum and the intestinal tract.
A DNA vaccine adjuvanted with cPNTs can effectively express the antigen and can significantly induce an antibody response against goose parvovirus through oral vaccination.
Over the last decade, parvovirus B19 (B19V) has frequently been linked to the pathogenesis of myocarditis (MC) and its progression towards dilated cardiomyopathy (DCM). The exact role of the presence ...of B19V and its load remains controversial, as this virus is also found in the heart of healthy subjects. Moreover, the prognostic relevance of B19V prevalence in endomyocardial biopsies still remains unclear. As a result, it is unclear whether the presence of B19V should be treated. This review provides an overview of recent literature investigating the presence of B19V and its pathophysiological relevance in MC and DCM, as well as in normal hearts. In brief, no difference in B19V prevalence is observed between MC/DCM and healthy control hearts. Therefore, the question remains open whether and how cardiac B19V may be of pathogenetic importance. Findings suggest that B19V is aetiologically relevant either in the presence of other cardiotropic viruses, or when B19V load is high and/or actively replicating, which both may maintain myocardial (low‐grade) inflammation. Therefore, future studies should focus on the prognostic relevance of the viral load, replicative status and virus co‐infections. In addition, the immunogenetic background of MC/DCM patients that makes them susceptible to develop heart failure upon presence of B19V should be more thoroughly investigated.
Objectives
To further clarify the causes of pancytopoenia and to investigate whether underlying cause or severity were associated with survival in an area endemic for vector‐borne pathogens.
Methods
...Retrospective review of medical records of 119 dogs with and 238 dogs without pancytopoenia.
Results
Mixed‐breed dogs and dogs younger than one year had higher odds of being pancytopoenic. The most common diagnoses included monocytic ehrlichiosis (n=42), leishmaniasis (n=28) and parvoviral enteritis (n=19). The mean white blood cell counts were lower in dogs with ehrlichiosis and parvoviral enteritis compared to dogs with leishmaniasis, while platelet counts were lower in ehrlichiosis compared to leishmaniasis or parvoviral enteritis. Total protein concentrations were lower in dogs with parvoviral enteritis compared to ehrlichiosis and leishmaniasis. Higher haematocrit, platelet and white cell counts were associated with better odds of survival.
Clinical Significance
Infectious diseases appear to be the leading causes of canine pancytopoenia in endemic areas; severe leukopoenia (ehrlichiosis, parvoviral enteritis), thrombocytopoenia (ehrlichiosis) and hypoproteinaemia (parvoviral enteritis), represented potentially useful disease‐specific diagnostic determinants. The severity of pancytopoenia significantly affects the clinical outcome.
Canine parvovirus infection remains to represent a worldwide and commonly occurring infectious disease leading to severe morbidity especially in puppies. The main therapeutic approach is primarily ...based on symptomatic treatment, especially addressing acute gastrointestinal signs as well as treating and preventing potential sepsis due to bacterial translocation. Besides antibiotic and essential fluid therapy, the use of efficient antiemetic and pain medication is required. In addition, early enteral nutrition should be attempted as this has been shown to be associated with a shorter time to recovery. Modulation of the intestinal microbiome could improve clinical signs and possibly aide in avoiding long-term sequelae such as chronic gastrointestinal disease. Treatment with recombinant feline interferon-omega resulted in a lower mortality and a more rapid improvement of clinical signs in several experimental and clinical studies and thus is considered to be effective.
Parvovirus B19 (B19V) infections are a common but under-investigated and under-reported cause of intrauterine infections. An increased number of acute B19V infections was identified in the Edinburgh ...area in 2012–2013, with 123 infections diagnosed in 33 pregnant women, 76 non-pregnant women and 14 men. All except one pregnant woman were asymptomatic. An overall infection rate of 18% was measured in pregnant women who were tested following B19V exposure (26/141). Furthermore, a 7% seroconversion rate was recorded in non-immune pregnant women who were re-tested after exposure (7/104). A high fetal loss rate (25%; 3/12) was observed in those who had acute B19V infection in early pregnancy (<11 weeks) whereas all pregnancies progressed to term in those where acute infection occurred after a gestational age of 12 weeks. These results suggest that more efforts should be targeted to investigate suspected B19V infections in early pregnancy during epidemic seasons.
We report the identification and genome characterization of a novel bocavirus, feline bocavirus (FBoV), and novel bocaviruses closely related to canine bocavirus (CBoV) strain Con-161 in stray cats ...and dogs in Hong Kong, respectively. FBoV was detected by PCR in 7.2, 0.3, 1.6, 2.0 and 0.8% of faecal, nasal, urine, kidney and blood samples, respectively, from 364 cats, while CBoV was detected in 4.6, 5.1, 6.3 and 0.3% of faecal, nasal, urine and blood samples, respectively, from 351 dogs. Three FBoV genomes sequenced revealed the presence of three ORFs characteristic of bocaviruses. Phylogenetic analysis showed that FBoVs were related only distantly to other bocaviruses, forming a distinct cluster within the genus, with ≤ 5.7% nucleotide identities to the genome of minute virus of canines. The four CBoV genomes sequenced shared 87.4-89.2% nucleotide identities with that of CBoV strain Con-161. In addition to the three bocavirus ORFs, they encoded an additional ORF, ORF4, immediately downstream of the ORF for non-structural protein 1 (NS1), which was not found in other bocaviruses including CBoV strain Con-161. They also possessed a putative second exon encoding the C-terminal region of NS1 and conserved RNA-splicing signals, previously described in human bocaviruses. Partial VP1/VP2 sequence analysis of 23 FBoV and 25 CBoV strains demonstrated inter-host genetic diversity, with two potential genetic groups of FBoV and a novel CBoV group, CBoV-HK, distinct from the three groups, CBoV-A to -C, found in the USA. Although the pathogenicity of FBoV and CBoV remains to be determined, their presence in different host tissues suggested wide tissue tropism.
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