Abstract
Objectives
The aim of the present study was to evaluate feline chaphamaparvovirus (FeChPV, previously referred to as feline fechavirus) in different cat populations.
Methods
Feces or vomit were collected from a convenience sample of cats in facilities undergoing clusters of undifferentiated vomiting and diarrhea, along with a single animal shelter that was not experiencing a detectable change in disease. Samples were tested for FeChPV using PCR.
Results
Fecal (n = 127) and vomitus (n = 9) samples were obtained from 136 cats: 65 from cats at an animal shelter without any apparent increase in gastrointestinal disease (shelter A); 25 from three animal shelters (shelters B–D) with clusters of undifferentiated acute onset of vomiting and diarrhea; and 46 from a research colony that had a recent outbreak of gastrointestinal disease. FeChPV was identified in 30/136 (22%) samples: 8/65 (12%) of cats from shelter A; 1/9 (11%) from shelter B; 2/8 (25%) from shelter C; 7/8 (88%) from shelter D; and 12/46 (26%) cats from the research colony. Among the samples from shelter A, the shelter with no identified abnormal gastrointestinal disease, FeChPV DNA was identified in the feces of 5/52 (9.6%) non-diarrheic (fecal score <4) and 3/13 (23%) diarrheic cats (P = 0.19). Overall, FeChPV was found in 14/43 (33%) diarrheic and 16/93 (17%) healthy cats (P = 0.07). Facility was the only variable that was significant on multivariable analysis, with the odds of PCR positivity being 5.7 times higher in shelter D compared with other facilities (95% confidence interval 2.3–25; P <0.0001).
Conclusions and relevance
FeChPV was commonly found in a shelter experiencing acute gastrointestinal disease but was also found in healthy cats and in facilities with no apparent increase in disease. The role of this virus in feline gastrointestinal disease and facility outbreaks is unclear.
Plain language summary
Feline chaphamaparvovirus (FeChPV, previously referred to as feline fechavirus) is a potentially emerging cause of vomiting and diarrhea in cats. This study aimed to assess the presence of FeChPV in different cat populations. Feces or vomit were collected from of cats in facilities undergoing clusters of undifferentiated vomiting and diarrhea, along with a single animal shelter that was not experiencing a detectable change in disease. Samples were tested for FeChPV by PCR. Fecal (n = 127) and vomitus (n = 9) samples were obtained from 136 cats: 65 from cats at an animal shelter without any apparent increase in gastrointestinal disease (shelter A); 25 from three animal shelters (shelters B–D) with clusters of undifferentiated acute onset of vomiting and diarrhea; and 46 from a research colony that had a recent outbreak of gastrointestinal disease. FeChPV was identified in 30/136 (22%) samples: 8/65 (12%) of cats from shelter A; 1/9 (11%) from shelter B; 2/8 (25%) from shelter C; 7/8 (88%) from shelter D; and 12/46 (26%) from the research colony. Among the samples from shelter A, the shelter with no identified abnormal gastrointestinal disease, FeChPV DNA was identified in the feces of 5/52 (9.6%) non-diarrheic (fecal score <4) and 3/13 (23%) diarrheic cats (P = 0.19). Overall, FeChPV was found in 14/43 (33%) diarrheic and 16/93 (17%) healthy cats (P = 0.07). FeChPV was commonly found in a shelter experiencing acute gastrointestinal disease but was also found in healthy cats and in facilities with no apparent increase in disease. The role of this virus in feline gastrointestinal disease and facility outbreaks is unclear.
Introduction
Gastrointestinal disease is an important problem in cats, particularly in group housing situations. Various infectious causes of gastrointestinal disease are recognized in cats; however, even with intensive investigation, a cause is often not identified. Recent advances in infectious disease testing, particularly metagenomics, have helped identify ‘new’ pathogens; however, ‘finding’ and ‘understanding’ are different issues.
One such new and poorly studied virus is feline chaphamaparvovirus (FeChPV), also referred to as feline fechavirus. This virus is a member of the Parvoviridae family, distantly related to pathogens such as feline panleukopenia virus and canine parvovirus. 1
FeChPV, reported as feline fechavirus, was first reported in 2020 1 after an outbreak of intestinal disease in cats at three animal shelters in British Columbia. It was identified in the feces of cats with vomiting and/or diarrhea, in the absence of other known pathogens. Disease was severe enough that 67% of affected cats required veterinary care. Transmission between cats and between shelters was identified and attack rates of 67–83% were reported, highlighting the transmissibility and potential for outbreaks. Subsequent study has been limited, and the epidemiology and clinical relevance of FeChPV remain unclear. FeChPV has been reported in 3.2–47% of cats with gastrointestinal disease.2 –6 However, studies in healthy cats have been more limited, although the virus has been detected in healthy cats, with reported prevalence rates of 0–9.1%.3,5,7,8 Studies directly comparing diseased and healthy populations are limited, and multiple studies have reported no association between FeChPV and diarrhea.3,8
Understanding the relevance of FeChPV is important to better understand whether efforts for diagnosis, treatment or prevention are warranted. The objective of this study was to evaluate FeChPV in different cat populations.
Materials and methods
Feces or vomit were collected from cats from a convenience sample of facilities undergoing clusters of undifferentiated vomiting and diarrhea, along with a single animal shelter that was not experiencing a detectable change in gastrointestinal disease. Limited metadata were available beyond health status. The Bristol fecal score was provided for cats from the unaffected shelter. The study was approved by the University of Guelph Animal Care Committee.
DNA was extracted using a commercial kit (QIAamp MiniElute Virus Spin Kit; Qiagen). Nested PCR was used to detect FeChPV, as per published protocols. 1 Two PCR assays were performed. The first involved primers FechaF1 (5’-GGTGCGACGACGGAAGATAT-3’) and FechaR1 (5’-CAACACCACCATCTCCTGCT-3’), amplifying a 332 base pair (bp) region. The second PCR used primers FechaF2 (5’-GCTGCAGTTCAGGTAGCTCA-3’) and FechaR1 to amplify a 310 bp region. Positive and negative controls were included in every PCR run. Positive control consisted of a synthetic DNA construct, as positive fecal samples were not initially available.
The Wilcoxon test was used to evaluate the association between fecal score and PCR positivity. Stepwise forward logistic regression was used for multivariable analysis. Variables with a liberal P value of 0.20 were entered into the model. P <0.05 in the final model was considered significant. Odds ratios and 95% confidence intervals (CIs) were calculated.
Results
Fecal (n = 127) or vomitus (n = 9) samples were obtained from 136 cats: 65 from cats with and without gastrointestinal disease at an animal shelter in Ontario, Canada without any apparent increase in gastrointestinal disease (shelter A); 25 from three animal shelters (shelters B–D) in British Columbia, Canada with ongoing outbreaks of gastrointestinal disease; and 46 from one research colony in Ontario with clusters of undifferentiated acute onset of vomiting and diarrhea.
FeChPV DNA was identified in 30/136 (22%) cats (95% CI 15–29) (Table 1): 14/43 (33%) cats with gastrointestinal disease and 16/93 (17%) in cats without gastrointestinal disease (P = 0.07).
Prevalence of feline chaphamaparvovirus (FeChPV) in feces or vomitus of cats from animal shelters and a research colony
Data are n (%)
GI = gastrointestinal; NT = not tested
Among the samples from shelter A, there was no association between detection of FeChPV and presence of diarrhea, as FeChPV DNA was identified in the feces of 5/52 (9.6%) non-diarrheic (fecal score <4) and 3/13 (23%) diarrheic cats (P = 0.19). There was also no association between PCR positivity and fecal score, with a median fecal score of 3 (interquartile range [IQR] 3) in the positive group and a median of 2 (IQR 2) in the negative group (P = 0.86).
For the research colony, samples were collected from cats at three different timepoints over approximately 3 months. Sampling was commenced after recognition of an outbreak of vomiting and diarrhea, with no other pathogens detected via a commercial PCR panel that included testing for Campylobacter coli, Campylobacter jejuni, Clostridium perfringens, Clostridium perfringens enterotoxin, Cryptosporidium species, feline coronavirus, feline panleukopenia virus, Giardia species, Salmonella species, Toxoplasma gondii and Tritrichomonas blagburni. FeChPV DNA was identified in 1/5 (20%) cats at the first time point, when active gastrointestinal disease was present, in 8/21 (38%) cats approximately 3 weeks later and in 3/20 (15%) cats approximately 6 weeks thereafter, both of the latter time points occurring after resolution of the outbreak. Two cats were sampled twice. One was positive at time point 1 and negative at the next time point. The other tested negative at both time points 2 and 3.
There was a significantly higher rate of detection of FeChPV DNA in cats from affected facilities vs the unaffected shelter (22/71 [31%] vs 8/65 [12%]; P = 0.01), vomitus vs feces (5/9 [56%] vs 25/127 [20%]; P = 0.01) and between facilities (P = 0.0001). Facility was the only variable that was significant on multivariable analysis, with the odds of PCR positivity being 5.7 times higher in shelter D compared with other facilities (95% CI 2.3–25; P <0.0001).
Discussion
This study identified FeChPV in all studied populations, at varying prevalences. It was noteworthy that FeChPV was commonly found in healthy cats, with an overall prevalence of 17%. This does not exclude FeChPV as a pathogen, as it is common for gastrointestinal pathogens to be detectable in a subset of healthy individuals, but highlights the need to investigate healthy controls when investigating potential new pathogens.
Overall, there was not a significant association between the presence of FeChPV and gastrointestinal disease, but the P value approached significance (P = 0.07). The numerical but non-statistically significant difference that was present in diarrheic vs non-diarrheic cats (33% vs 17%) cannot indicate an association with disease but supports the need for broader study. More study of comparable populations of healthy individuals and controls is needed, as healthy controls were not available from 3/5 facilities that were studied. Overall, these results add more information for assessment of the potential role of FeChPV and provide useful prevalence data for future prevalence meta-analysis. They cannot answer the question of whether FeChPV is a pathogen, something that is difficult for any single study to achieve. This result is consistent with other studies that have found FeChPV in both healthy and diseased cats,2 –8 with an uncertain but potential role in disease.
Small sample sizes were available for the three shelters experiencing acute vomiting and diarrhea outbreaks. Nevertheless, these data are informative and highlight both a potential association with outbreaks and the presence of a baseline level of the virus in sheltered cats. The presence of FeChPV in 7/8 cats with gastrointestinal disease in one shelter supports an outbreak; however, this cannot be confirmed without better understanding of the virulence of the virus and more robust diagnostic testing to exclude other feline pathogens. Testing for other pathogens in sheltered cats was not performed here, as is common in resource-limited settings.
The research colony provides other interesting insights. Sampling was started a few weeks after an onset of an outbreak of undifferentiated gastrointestinal disease. The prevalence varied between three different sampling dates as the outbreak waned, with a range of 15–38%. Only a convenience sample of a subset of cats was tested each time, with limited metadata. Therefore, it is challenging to interpret the results with respect to disease. However, this shows the potential for entry of this virus into colonies with strict biosecurity practices and the potential for widespread dissemination. Whether FeChPV was the cause of disease remains uncertain but is possible given the consistency of clinical signs with previous reports and lack of another identifiable cause.
In addition to the study of shelter and colony populations, there is a need for investigation of FeChPV in homed cats, as the risk and role in disease may differ from dense and often stressed group populations, animals that may also be exposed to various potential co-infections. The role of FeChPV in acute gastrointestinal disease in homed cats has been inadequately investigated. Given the markedly different risks in shelters, with congregate care, transient populations, typically younger populations, stress and other factors that facilitate entry and dissemination of enteropathogens, shelter data cannot necessarily be extrapolated to the community.
Most testing was carried out on fecal samples, but a small number of vomitus samples was obtained. The high positivity rate (56% for vomitus vs 20% for feces) suggests that testing of both feces and vomitus should be considered.
Conclusions
Limitations in sample size, number of facilities and available metadata restrict the ability to determine the role of feline FeChPV in disease. However, this study provides additional information about this poorly studied virus, showing its presence in both healthy and diseased cats, as well as in facilities with and without apparent increases in gastrointestinal disease. Although it may be capable of causing outbreaks, its detection alone does not indicate that an outbreak is occurring or will occur. The facilities included in this study were located in two geographically distinct provinces in Canada, suggesting that the virus is widely distributed within the feline population. Further studies involving larger numbers of cats across different facility types and geographic regions, ideally with more robust health data, are required to help clarify the role of this virus in disease.
Footnotes
Conflict of interest
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
This study was supported by the Ontario Veterinary College Pet Trust.
Ethical approval
The work described in this manuscript involved the use of non-experimental (owned or unowned) animals. Established internationally recognized high standards (‘best practice’) of veterinary clinical care for the individual patient were always followed and/or this work involved the use of cadavers. Ethical approval from a committee was therefore not specifically required for publication in JFMS. Although not required, where ethical approval was still obtained, it is stated in the manuscript.
Informed consent
Informed consent (verbal or written) was obtained from the owner or legal custodian of all animal(s) described in this work (experimental or non-experimental animals, including cadavers, tissues and samples) for all procedure(s) undertaken (prospective or retrospective studies). No animals or people are identifiable within this publication, and therefore additional informed consent for publication was not required.
