Viral burden and diversity in acute respiratory tract infections in hospitalized children in wet and dry zones of Sri Lanka.

The present study was done to identify the viral diversity, seasonality and burden associated with childhood acute respiratory tract infection (ARTI) in Sri Lanka. Nasopharyngeal aspirates (NPA) of hospitalized children (1 month-5 years) with ARTI were collected in 2 centers (wet and dry zones) from March 2013 to August 2014. Respiratory viral antigen detection by immunofluorescence assay (IFA) was used to identify the infecting viruses. IFA negative 100 NPA samples were tested for human metapeumovirus (hMPV), human bocavirus and corona viruses by polymerase chain reaction. Of the 443 and 418 NPAs, 37.2% and 39.4% were positive for any of the 8 different respiratory viruses tested from two centers studied. Viral co-infection was detected with respiratory syncytial virus (RSV) in both centers. Peak viral detection was noted in the wet zone from May-July 2013 and 2014 and in the dry zone from December-January 2014 suggesting a local seasonality for viral ARTI. RSV showed a clear seasonality with a direct correlation of monthly RSV infections with rainy days in the wet zone and an inverse correlation with temperature in both centers. The case fatality rate was 2.7% for RSV associated ARTI. The overall disability adjusted life years was 335.9 and for RSV associated ARTI it was 241.8. RSV was the commonly detected respiratory virus with an annual seasonality and distribution in rainy seasons in the dry and wet zones of Sri Lanka. Identifying the virus and seasonality will contribute to employ preventive measures and reduce the empirical use of antibiotics in resource limited settings.

Mass mortality in freshwater mussels (Actinonaias pectorosa) in the Clinch River, USA, linked to a novel densovirus.

Freshwater mussels (order Unionida) are among the world's most biodiverse but imperiled taxa. Recent unionid mass mortality events around the world threaten ecosystem services such as water filtration, nutrient cycling, habitat stabilization, and food web enhancement, but causes have remained elusive. To examine potential infectious causes of these declines, we studied mussels in Clinch River, Virginia and Tennessee, USA, where the endemic and once-predominant pheasantshell (Actinonaias pectorosa) has suffered precipitous declines since approximately 2016. Using metagenomics, we identified 17 novel viruses in Clinch River pheasantshells. However, only one virus, a novel densovirus (Parvoviridae; Densovirinae), was epidemiologically linked to morbidity. Clinch densovirus 1 was 11.2 times more likely to be found in cases (moribund mussels) than controls (apparently healthy mussels from the same or matched sites), and cases had 2.7 (log10) times higher viral loads than controls. Densoviruses cause lethal epidemic disease in invertebrates, including shrimp, cockroaches, crickets, moths, crayfish, and sea stars. Viral infection warrants consideration as a factor in unionid mass mortality events either as a direct cause, an indirect consequence of physiological compromise, or a factor interacting with other biological and ecological stressors to precipitate mortality.

Predictors of Mortality in Patients With Biopsy-Proven Viral Myocarditis: 10-Year Outcome Data.

Background There is scarce data about the long-term mortality as well as the prognostic value of cardiovascular magnetic resonance and late gadolinium enhancement (LGE) in patients with biopsy-proven viral myocarditis. We sought to investigate: (1) mortality and (2) prognostic value of LGEcardiovascular magnetic resonance (location, pattern, extent, and distribution) in a >10-year follow-up in patients with biopsy-proven myocarditis. Methods and Results Two-hundred three consecutive patients with biopsy-proven viral myocarditis and cardiovascular magnetic resonance were enrolled; 183 patients were eligible for standardized follow-up. The median follow-up was 10.1 years. End points were all-cause death, cardiac death, and sudden cardiac death (SCD). We found substantial long-term mortality in patients with biopsy-proven myocarditis (39.3% all cause, 27.3% cardiac, and 10.9% SCD); 101 patients (55.2%) demonstrated LGE. The presence of LGE was associated with a more than a doubled risk of death (hazard ratio [HR], 2.40; 95% CI], 1.30-4.43), escalating to a HR of 3.00 (95% CI, 1.41-6.42) for cardiac death, and a HR of 14.79 (95% CI, 1.95-112.00) for SCD; all P≤0.009. Specifically, midwall, (antero-) septal LGE, and extent of LGE were highly associated with death, all P<0.001. Septal LGE was the best independent predictor for SCD (HR, 4.59; 95% CI, 1.38-15.24; P=0.01). Conclusions In patients with biopsy-proven viral myocarditis, the presence of midwall LGE in the (antero-) septal segments is associated with a higher rate of mortality (including SCD) compared with absent LGE or other LGE patterns, underlining the prognostic benefit of a distinct LGE analysis in these patients.

Sole recombinant Muscovy duck parvovirus infection in Muscovy ducklings can form characteristic intestinal embolism.

Recombinant Muscovy duck parvovirus (rMDPV) has been recently identified as a novel pathogen circulating in Chinese Muscovy duck flocks in the past two decades. Different from classical MDPV, rMDPV infection can form embolism in the intestinal tract of deceased Muscovy ducklings. However, whether rMDPV acts as the sole causative agent involved in the formation of the characteristic embolism in Muscovy ducklings remains unclear. In this study, an infectious plasmid clone pZW containing the complete genome of strain ZW, a previously characterized rMDPV isolate, was constructed, and a single nucleotide mutation was then introduced in the VP1 gene within pZW as the genetic marker. Transfection of pZW in 11-day-old embryonated Muscovy duck eggs via the chorioallantoic membrane route resulted in the rescue of the infectious virus. The rescued virus exhibited similar biological characteristics to its parental strain ZW, as evaluated by the median embryo lethal dose and the replication kinetics in embryonated Muscovy duck eggs. Muscovy duckling infection tests showed that the rescued virus and parental strain can kill all Muscovy ducklings within 7 days post-infection. Postmortem examination revealed that embolism can be observed in the intestinal tracts of deceased ducklings in the rescued and parental virus infection groups. Collectively, the present study demonstrated that sole rMDPV infection of Muscovy ducklings, without participation of other pathogens, is enough to form characteristic embolism in the intestinal tract.

Comparison and validation of different models and variable selection methods for predicting survival after canine parvovirus infection.

BACKGROUND: Canine parvovirus (CPV) represents one of the major infections in dogs. While supportive therapy significantly reduces mortality, other approaches have been reported to provide significant benefits. Unfortunately, the high cost of these treatments is typically a limiting factor. Consequently, a reliable prognostic tool allowing for an informed therapeutic approach would be of great interest. However, current methods are essentially based on 'a priori' selection of predictive variables, which could limit their predictive potential. METHODS: In the present study, the predictive performances in terms of CPV enteritis survival likelihood of an operator-validated logistic regression were compared with those of more flexible methods featured by automatic variable selection. Several anamnestic, clinical, haematological and biochemical parameters were collected from 134 dogs at admission in a veterinary practice. Animal status was monitored until dismissal or death (mortality=21.6%). RESULTS: The best automatic variable selection method (random forest) showed excellent discriminatory capabilities (AUC=0.997, sensitivity=0.941 and specificity=1) compared with the logistic regression model (AUC=0.831, sensitivity=0.882 and specificity=0.652), when evaluated on a fully independent test data set. The implemented approaches allowed to identify antithrombin, serum aspartate aminotransferase, serum lipase, monocyte and lymphocyte count as the clinical parameter combination with the highest predictive capability, thus limiting the panel of required tests. CONCLUSION: The model validated in the present study allows prompt prediction of disease severity at admission and provides objective and reliable criteria to support the clinician in selection of the therapeutic approach.

Fatal Primary Human Bocavirus Pneumonia in an Immunocompetent Adult.

A 70-year-old woman was admitted to our hospital for dyspnea and a fever of 2 weeks duration. Chest imaging showed bilateral infiltration, and a rapid diagnostic test for influenza virus, Mycoplasma pneumoniae, Streptococcus pneumoniae, and Legionella spp. was negative. She was intubated and mechanically ventilated and underwent bronchoalveolar lavage. Bronchoalveolar lavage fluid yielded no significant pathogens, and the multiplex polymerase chain reaction test was positive only for human bocavirus. Specific antibodies against significant pathogens were not increased in paired sera, so we diagnosed her with primary human bocavirus pneumonia.

First characterization of a canine parvovirus causing fatal disease in coatis (Nasua nasua).

A canine parvovirus (CPV)-like virus was detected by PCR and isolated from dead coatis in Argentina. Analysis of the full-length genome sequence revealed that it resembled CPV-but also contained a mutation in the VP2 protein (Arg377Ser) that has not been described previously. This is the first report of a CPV-like virus producing clinical disease in coatis. Genetic similarity to CPV-2c viruses detected in Brazil suggests a strong relationship between these viruses. Although the pathogenic potential of CPV- and feline panleukopenia virus (FPV)-like strains in wild animals is still not completely understood, this study highlights the importance of parvoviruses as a threat to wildlife if proper conditions are present.

Effect of Canine Parvovirus and Canine Distemper Virus on the Mexican Wolf (Canis lupus baileyi) Population in the USA.

Mexican wolves (Canis lupus baileyi), classified as probably extinct in the wild in Mexico and endangered in the US, were reintroduced into Arizona in 1998. We combined annual serologic testing results from samples collected between 2003 and 2016 from 108 wolves and known survival data from 118 wolves born in the recovery area from 2003 to 2014 to evaluate whether exposure to canine distemper virus (CDV) or canine parvovirus (CPV) was associated with a greater risk of mortality before 2 yr of age. We used mixed-effects logistic regression to estimate the effect of CDV and CPV on the probability of mortality. Annual seroprevalence rates for CDV and CPV ranged from 0% to 62% and from 33% to 100%, respectively (median, 14.2% and 90.3%, respectively). The covariate, age at testing, had a negative effect on mortality, indicating that younger animals had lower survival, whereas sex had little effect on mortality. The best-supported model excluded any effect of CPV or CDV on death before 2 yr old at both the pack and individual level. Although our analysis did not detect an effect of these viruses on mortality before 2 yr old, CDV was later identified as the cause of mortality in two individuals in 2017. Additional information is needed to assess the impact of these diseases on Mexican wolves.

Does an intrauterine exchange transfusion improve the fetal prognosis in parvovirus infection cases?

BACKGROUND: Almost 20% of parvovirus B19 foetal infections require intrauterine transfusions. In addition, myocardial dysfunction has been observed in severe parvovirus B19 infections. One objective of an intrauterine exchange transfusion (IUET) is to avoid an overload during the transfusion. Our aim was to study the obstetrical and neonatal outcomes in cases of IUETs performed for foetal parvovirus infections and to compare our survival rate to those studies in which simple in utero transfusions were chosen. STUDY DESIGN AND METHODS: This was a retrospective monocentre study of all patients followed up for parvovirus B19 infections in which IUETs were performed. An IUET was indicated when foetal hydrops was observed and/or when severe foetal anaemia was diagnosed though an elevation in the middle cerebral artery peak systolic velocity. The characteristics of each pregnancy and the neonatal outcomes were studied until hospital discharge. RESULTS: Thirty-five IUETs were performed in 26 foetuses. The median gestational age of the first IUET was 22.6 weeks. Only one foetal bradycardia incidence was recorded during the procedure. Three medical pregnancy terminations were observed in our series, secondary to severe cerebral anomalies confirmed in the magnetic resonance imaging. Five in utero deaths occurred, in which 2 of the foetuses underwent multiple IUETs. All the neonates had normal haemoglobin levels at birth, and none were transferred to the neonatal intensive care unit. The overall survival rate was 70%. CONCLUSION: IUETs exhibit a survival rate similar to that of simple intrauterine transfusions in foetal parvovirus infection cases.

Pathogenicity of a variant goose parvovirus, from short beak and dwarfism syndrome of Pekin ducks, in goose embryos and goslings.

The pathogenicity of a variant goose parvovirus (GPV), isolated from short beak and dwarfism syndrome of Pekin ducks (strain Cherry Valley), was investigated in embryonating goose eggs and goslings. The virus was easily grown in GPV antibody-free goose embryos and caused high mortality and severe lesions of goose embryos, indicating that the variant GPV has good adaptation and high pathogenicity to embryonated goose eggs similar to the classical GPV. Like the third egg-passage virus (strain H) of a classical GPV, the third egg-passage virus (strain JS1) of the variant GPV caused Derzsy's disease in 2-day-old goslings with high mortality. The findings suggest that the variant GPV strain, which had specifically adapted to Pekin ducks, still retained high pathogenicity for its original host. The mortality (73.3-80%) caused by the first and third egg-passages of the variant GPV was somewhat lower than that (93.3%) caused by the third passage virus of the classical GPV, reflecting the higher pathogenicity of the classical GPV for its original host. These findings are likely to reinforce the importance of surveillance for parvoviruses in different waterfowl species and stimulate further study to elucidate the impact of mutations in the GPV genome on its pathogenicity to goslings and ducks.

Factors affecting the occurrence of canine parvovirus in dogs.

Canine parvovirus (CPV) is the most important enteric virus infecting canids worldwide. The purpose of this study was to detect CPV in naturally infected dogs from several veterinary clinics distributed throughout Portugal between 2012 and 2014 and to identify risk factors associated with CPV infection. From 209 dogs suspected of being infected with CPV, historical data and clinical signs were collected. Fecal samples were screened for CPV by PCR assay and those positive were confirmed by sequencing. The data was analyzed using logistic regression to investigate associations between each of the predisposing factors and CPV status. Of the samples collected, 77.5% tested CPV-positive. Statistical analysis showed that animals in the three age categories (p<0.001) were at list 12 times more likely to be CPV-positive than older animals. The anthelminthic treatment [OR=0.45, p=0.04] and the rectal temperature (hypothermia, [OR=0.12, p=0.004]) contributed to decrease the likelihood of the dogs be infected with CPV. On the other hand, clinical signs such as depression [OR=4.4, p=0.02] and dehydration status [OR=2.38, p=0.001] made dogs more likely to be CPV-infected. The results indicate that although having a high morbidity, only 18% of the Portuguese dog population died in the study. Some of the risk factors identified in this study have not been commonly reported, yet they are easy to obtain and can be used as prognostic indicators in the veterinary practice.

[DIAGNOSTIC VALUE OF COMBINED USE OF COMBINED METHOD OF ENZYME IMMUNOASSAY AND POLYMERASE CHAIN REACTION TO DETECT OF INTRAUTERINE FETAL INFECTION BY PARVOVIRUS B19].

The combined method of diagnosis parvovirus infection during pregnancy by maternal serum enzyme immunoassay and deoxyribonucleic acid isolation parvovirus B19 polymerase chain reaction in amnniotic fluid and fetal cord blood newborns, can diagnose vertical transmission and anticipate a negative effect on the fetus parvovirus. Lack of maternal IgM antibodies in serum due to parvovirus seroconversion during pregnancy does not exclude the persistence of the virus in the fetus. To analyze the diagnostic value of the method for determining the LHP parvovirus B19 DNA in the amniotic fluid, umbilical cord blood of newborns to determine vertical transmission of parvovirus infection when infected mothers B19 during pregnancy.

The presence of enterovirus, adenovirus, and parvovirus B19 in myocardial tissue samples from autopsies: an evaluation of their frequencies in deceased individuals with myocarditis and in non-inflamed control hearts.

PURPOSE: Multiple viruses have been detected in cardiac tissue, but their role in causing myocarditis remains controversial. Viral diagnostics are increasingly used in forensic medicine, but the interpretation of the results can sometimes be challenging. In this study, we examined the prevalence of adenovirus, enterovirus, and parvovirus B19 (PVB) in myocardial autopsy samples from myocarditis related deaths and in non-inflamed control hearts in an effort to clarify their significance as the causes of myocarditis in a forensic material. METHODS: We collected all autopsy cases diagnosed with myocarditis from 1992 to 2010. Eighty-four suicidal deaths with morphologically normal hearts served as controls. Polymerase chain reaction was used for the detection of the viral genomes (adenovirus, enterovirus, and PVB) in myocardial tissue specimens. The distinction between acute and persistent PVB infection was made by the serological determination of PVB-specific immunoglobulins M and G. RESULTS: PVB was detected in 33 of 112 (29 %) myocarditis cases and 37 of 84 (44 %) control cases. All of the samples were negative for the presence of adenovirus and enterovirus. Serological evidence of an acute PVB infection, determined by the presence of immunoglobulin M, was only present in one case. In the remaining cases, PVB was considered to be a bystander with no or limited association to myocardial inflammation. CONCLUSION: In this study, adenovirus, enterovirus, and PVB were found to be rare causes of myocarditis. The detection of PVB in myocardial autopsy samples most likely represents a persistent infection with no or limited association with myocardial inflammation. The forensic investigation of myocardial inflammation demands a thorough examination, including special attention to non-viral causes and requires a multidisciplinary approach.

Molecular typing of canine parvovirus strains circulating from 2008 to 2012 in an organized kennel in India reveals the possibility of vaccination failure.

Canine parvovirus-2 (CPV-2), which emerged in 1978, is considered as the major viral enteric pathogen of the canine population. With the emergence of new antigenic variants and incidences of vaccine failure, CPV has become one of the dreaded diseases of the canines worldwide. The present study was undertaken in an organized kennel from North India to ascertain the molecular basis of the CPV outbreaks in the vaccinated dogs. 415 samples were collected over a 5year period (2008-2012). The outbreak of the disease was more severe in 2012 with high incidence of mortality in pups with pronounced clinical symptoms. Molecular typing based on the VP2 gene was carried out with the 11 isolates from different years and compared with the CPV prototype and the vaccine strains. All the isolates in the study were either new CPV-2a (2012 isolates) or new CPV-2b (2008 and 2011 isolates). There were amino acid mutations at the Tyr324Ile and at the Thr440Ala position in five isolates from 2012 indicating new CPV mutants spreading in India. The CPV vaccines used in the present study failed to generate protective antibody titer against heterogeneous CPV antigenic types. The findings were confirmed when the affected pups were treated with hyper-immune heterogeneous purified immunoglobulin's against CPV in dogs of different antigenic types.

Parvovirus B19 infection in pregnancy and subsequent morbidity and mortality in offspring.

BACKGROUND: Because parvovirus B19 infection in pregnancy has been associated with infant morbidity and mortality in case reports and after intrauterine transfusion, we tested the population-based association using serum and hospital data of high quality. METHODS: We established a cohort of 113 228 children born to women tested for parvovirus B19 infection during pregnancy in a major diagnostic laboratory in Denmark, from 1994 to 2009. Information on 20 selected morbidity diagnoses and on mortality was obtained from the Danish National Patient Register, the Danish Cancer Register and the Danish Civil Registration System. Incidence rate ratios (IRR) were estimated by log-linear Poisson regression with adjustment for age and sex of the child, maternal age and year of maternal parvovirus B19 test. RESULTS: A total of 1095 (1.0%) children were born to mothers who were infected with parvovirus B19 during pregnancy. During 1 million person-years of follow-up, 10 856 children experienced morbidity and 590 children died. Overall, maternal infection status was neither associated with morbidity during infancy (IRR 0.64; 95% CI: 0.40 to 1.02) or childhood (IRR 0.93; 95% CI: 0.77 to 1.14), nor with infant mortality (IRR 0.98; 95% CI: 0.44 to 2.20). Specifically, there was no association with 19 of 20 morbidities. An excess risk of cancer in the central nervous system was observed (IRR 5.88; 95% CI: 1.41 to 24.6); however, the number of exposed cases was very small (n = 2). CONCLUSIONS: Parvovirus B19 infection during pregnancy was not associated with overall morbidity or mortality in infancy and childhood.

Evaluation of the use of serum C-reactive protein concentration to predict outcome in puppies infected with canine parvovirus.

OBJECTIVE: To evaluate associations of serum C-reactive protein (CRP) concentration with duration of hospitalization and with outcome in puppies with canine parvoviral enteritis. DESIGN: Prospective observational study. Animals-79 client-owned puppies with naturally acquired canine parvovirus infection. PROCEDURES: All puppies received supportive care. Serum CRP concentration was measured at the time of admission, approximately every 10 to 12 hours for the first 48 hours, and then every 24 hours until discharge from the hospital or death. Associations between outcome and CRP concentration at various time points or changes in CRP concentration over time were assessed via multiple logistic regression. Associations of CRP concentration with survival time and duration of hospitalization among survivors were estimated with Cox proportional hazards regression. Use of CRP concentration to predict outcome was evaluated by means of receiver operating characteristic curve analysis. RESULTS: Serum CRP concentrations at admission and 12 and 24 hours later were positively associated with odds of death, and CRP concentrations at 12 and 24 hours after admission were negatively associated with survival time for puppies. Among survivors, duration of hospitalization was positively associated with CRP concentrations at 12, 24, and 36 hours after admission. Sensitivity and specificity of CRP concentration to differentiate between survivors and nonsurvivors at 24 hours after admission were 86.7% and 78.7%, respectively (considered moderately accurate). CONCLUSIONS AND CLINICAL RELEVANCE: Although serum CRP concentration was associated with outcome in puppies with canine parvovirus enteritis, it did not prove to be a good predictor of outcome when used alone.

Risk factors for death from canine parvoviral-related disease in Australia.

Canine parvovirus (CPV) is a highly contagious cause of serious and often fatal disease in dogs worldwide despite the availability of safe and efficacious vaccines. Although a number of studies have focussed on identifying risk factors in disease development, risk factors associated with death from CPV are largely unknown. In this study we analysed a total of 1451 CPV cases reported from an Australian surveillance system - using univariate and multivariate techniques - to determine significant risk factors associated with death and euthanasia. A crude case fatality rate of 42.3% was estimated - higher than has been reported previously. We found that 3.3% of CPV cases had a history of vaccination in the previous 12 months, despite having completed the primary puppy vaccination course. The majority (89.5%) of these cases occurred in dogs <12 months of age, indicating failure of the primary vaccination course to provide protective immunity (most likely due to interference of the vaccine antigen with maternal antibodies but other reasons are discussed). Extending the age at which the final puppy vaccination is administered might be one of several strategies to consider. The final multivariate model showed that in non-litter CPV cases, risk of death was significantly associated with season of diagnosis (summer) and pedigree type (hounds and non-sporting dogs). Euthanasia in non-litter CPV cases was significantly associated with season of diagnosis (summer), state of residence (Northern Territory/South Australia/Tasmania combined), age (

Parvovirus B19 in pregnancy: prenatal diagnosis and management of fetal complications.

PURPOSE OF REVIEW: Parvovirus B19 infection is often considered a mild and self-limiting disease of minor clinical importance. This review aims to raise awareness of recently discovered potentially devastating consequences of this infection in pregnancy, and provides updated guidelines on diagnosis and management. RECENT FINDINGS: In contrast to previous beliefs, parvovirus B19 infection during any stage of pregnancy may not only cause fetal death, but may also result in severe and irreversible neurological sequelae in survivors. Improved diagnostic techniques allow more reliable and earlier diagnosis of fetal disease. SUMMARY: Clinicians need to be aware of the risk of adverse outcome of parvovirus B19 infection in pregnancy, and sometimes the long interval between exposure and fetal symptoms. Accurate diagnosis using PCR and weekly ultrasound checks ups with Doppler measurement of middle cerebral artery flow velocity up to 20 weeks postexposure may improve detection of fetal disease. More timely treatment likely results in improved outcome.

Tei index (myocardial performance index) and cardiac biomarkers in dogs with parvoviral enteritis.

Tei index (myocardial performance) and cardiac biomarkers were evaluated in dogs with parvoviral enteritis (PVE). Tei index was calculated as isovolumic contraction time plus isovolumic relaxation time divided by ejection time. Myocardial and skeletal muscle damages were assessed by serum levels of cardiac troponin I (cTnI), creatine (phospho) kinase, lactate dehydrogenase and aspartate aminotransferase. Serum magnesium level was also determined. According to treatment response, dogs were divided into the survivor (n=20) and non-survivor groups (n=23). Seven healthy dogs served as controls. The mean value of the Tei index was higher in non-survivors, compared with survivors (p<0.02) and healthy controls (p<0.01). Serum level of cTnI in non-survivors was higher than that of survivors and controls (p<0.05). Tei index showed the highest sensitivity and specificity to predict mortality. The findings of an elevated Tei index and an increase in serum cTnI are factors associated with a poor prognosis in cases of canine parvovirosis.