Prevalence of serum antibody titers against canine distemper virus and canine parvovirus in dogs hospitalized in an intensive care unit

Jennifer L. Mahon Tufts Veterinary Emergency and Treatment Specialties, 525 South St, Walpole, MA 02081.

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Elizabeth A. Rozanski Department of Clinical Sciences, Cummings School of Veterinary Medicine, Tufts University, North Grafton, MA 01536.

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April L. Paul Tufts Veterinary Emergency and Treatment Specialties, 525 South St, Walpole, MA 02081.

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Abstract

OBJECTIVE To determine the prevalence of dogs hospitalized in an intensive care unit (ICU) with serum antibody titers against canine distemper virus (CDV) and canine parvovirus (CPV).

DESIGN Prospective observational study.

ANIMALS 80 dogs.

PROCEDURES Dogs hospitalized in an ICU for > 12 hours between February 1 and June 1, 2015, that had at least 0.25 mL of serum left over from diagnostic testing were eligible for study inclusion. Dogs with serum antibody titers > 1:32 (as determined by serum neutralization) and > 1:80 (as determined by hemagglutination inhibition) were considered seropositive for CDV and CPV, respectively. The date of last vaccination was obtained from the medical record of each dog.

RESULTS Of the 80 dogs, 40 (50%) and 65 (81%) dogs were seropositive for CDV and CPV, respectively. Of the 40 dogs that were seronegative for CDV, 27 had been vaccinated against CDV within 3 years prior to testing. Of the 15 dogs that were seronegative for CPV, 3 had been vaccinated against CPV within 3 years prior to testing. Ten dogs were seronegative for both CDV and CPV.

CONCLUSIONS AND CLINICAL RELEVANCE Results indicated the prevalence of dogs hospitalized in an ICU that were seropositive for CDV and CPV was lower than expected given the high vaccination rate reported for dogs. Although the antibody titer necessary to prevent disease caused by CDV or CPV in critically ill dogs is unknown, adherence to infectious disease control guidelines is warranted when CDV- or CPV-infected dogs are treated in an ICU.

Abstract

OBJECTIVE To determine the prevalence of dogs hospitalized in an intensive care unit (ICU) with serum antibody titers against canine distemper virus (CDV) and canine parvovirus (CPV).

DESIGN Prospective observational study.

ANIMALS 80 dogs.

PROCEDURES Dogs hospitalized in an ICU for > 12 hours between February 1 and June 1, 2015, that had at least 0.25 mL of serum left over from diagnostic testing were eligible for study inclusion. Dogs with serum antibody titers > 1:32 (as determined by serum neutralization) and > 1:80 (as determined by hemagglutination inhibition) were considered seropositive for CDV and CPV, respectively. The date of last vaccination was obtained from the medical record of each dog.

RESULTS Of the 80 dogs, 40 (50%) and 65 (81%) dogs were seropositive for CDV and CPV, respectively. Of the 40 dogs that were seronegative for CDV, 27 had been vaccinated against CDV within 3 years prior to testing. Of the 15 dogs that were seronegative for CPV, 3 had been vaccinated against CPV within 3 years prior to testing. Ten dogs were seronegative for both CDV and CPV.

CONCLUSIONS AND CLINICAL RELEVANCE Results indicated the prevalence of dogs hospitalized in an ICU that were seropositive for CDV and CPV was lower than expected given the high vaccination rate reported for dogs. Although the antibody titer necessary to prevent disease caused by CDV or CPV in critically ill dogs is unknown, adherence to infectious disease control guidelines is warranted when CDV- or CPV-infected dogs are treated in an ICU.

Canine distemper virus and CPV infect dogs and other species throughout the world. Canine distemper virus is a Morbillivirus that infects primarily dogs and ferrets. Clinical signs associated with CDV infection include vomiting, diarrhea, coughing, mucopurulent nasal discharge, hyperkeratosis of the foot pads and nose, and various neurologic abnormalities.1 Canine distemper virus is transmitted primarily by aerosol; the virus colonizes the respiratory tract; replicates in B cells, T cells, and macrophages; and then spreads throughout the body, invading epithelial cells and cells of the CNS.1,2 Mortality rates for CDV infection range from 30% to 50%, and the risk of death is dependent on the organ system affected.3,4

Canine parvovirus is a Protoparvovirus that infects dogs, but may have originated from cats. The survival rate for CPV-infected dogs is < 10% when left untreated and ranges from 64% to 95% when treated.5 Canine parvovirus is transmitted by fecal-oral transmission, and ingestion of CPV from fecal-contaminated fomites is considered an important mode of transmission. Clinical signs associated with CPV infection include vomiting and diarrhea, which lead to severe dehydration. The virus has an affinity for rapidly dividing cells, so crypt cells of the intestines and cells of the bone marrow are most commonly affected.6 Infected animals often develop severe neutropenia and may become septic.7

No antiviral agent is available for either CDV or CPV, and treatment of infected animals is largely supportive. However, vaccines against both viruses are widely available and considered very effective in preventing disease.8,9

Many dogs naturally infected with CDV or CPV develop only mild or moderate illness and can be treated either as outpatients or in isolation wards. However, some dogs infected with CDV or CPV become critically ill and require intensive supportive care, which can be hard to provide in a conventional isolation setting. Isolation units in veterinary hospitals are typically staffed only at treatment times, with patients monitored by video or audio monitors. That level of care may not be conducive for administration of supplemental oxygen, multiple drug infusions, or other intensive nursing support that critically ill animals may require. Results of a recent surveya indicate that > 50% of small animal ICUs staffed by diplomates of the American College of Veterinary Emergency and Critical Care treat CDV- and CPV-infected patients in the ICU with appropriate barrier measures.

Vaccination of companion dogs is widespread, and vaccination is a well-recognized method of controlling infectious disease both at the individual and population level. The American Animal Hospital Association has developed specific guidelines and recommendations for vaccination of dogs,10 and most dogs treated at referral hospitals are believed to be vaccinated in accordance with those guidelines.a

The objective of the study reported here was to ascertain whether dogs that were admitted to an ICU were seropositive for antibodies against CDV and CPV. Most dogs hospitalized in an ICU have been vaccinated and are considered protected against common viral diseases of dogs. Our hypothesis was that most dogs would be seropositive for antibodies against both CDV and CPV owing to high rates of vaccination.

Materials and Methods

Animals

All dogs hospitalized for > 12 hours in the ICU of the Foster Hospital for Small Animals at the Cummings School of Veterinary Medicine at Tufts University between February 1 and June 1, 2015, that had a serum sample collected for other diagnostic purposes were eligible for study inclusion. The ICU houses critically ill and injured animals that require 24-hour nursing care and is separate from a fluids or step-down ward. For a dog to be included in the study, a minimum of 0.25 mL of serum obtained from a serum separator tube had to be left over from other diagnostic testing and available for analysis. Each serum sample was decanted from the serum separator tube into a cryogenic vial. If multiple leftover serum samples were available for the same patient, the samples were pooled when necessary to achieve a minimum volume of 0.25 mL. Samples were stored at 4°C until they were sent to the reference laboratory, at which time they were packaged with ice packs and shipped overnight to the laboratory. The study was approved by the Tufts University Clinical Sciences Review Committee, and all samples were handled in accordance with that committee's policy for the use of leftover laboratory samples.

Serologic analysis

All serologic analyses were performed in batches by the Cornell University College of Veterinary Medicine Animal Health Diagnostic Center, and the results were reported in accordance with the cutoff values and reference ranges established by that laboratory. The antibody titers against CDV and CPV were determined by serum neutralization and hemagglutination inhibition assays, respectively, as described.11,12 Dogs with serum antibody titers > 1:32 and > 1:80 were considered seropositive for CDV and CPV, respectively.

Data collection

For each dog enrolled in the study, the vaccination history, including the date and manufacturer of the last vaccine administered, was obtained from the medical record or referring veterinarian and owner. Each dog was classified into 1 of 4 vaccination categories on the basis of vaccination history and American Animal Hospital Association Canine Vaccination Guidelines10 (up-to-date per the referring veterinarian's records [UTD-V], up-to-date per owner without veterinary record confirmation [UTD-O], not up-to-date per referring veterinarian's records [NUTD], or unknown vaccination history [unknown]). Dogs for which the last date of vaccination could not be provided by the primary care or referring veterinarian or the owner were classified in the unknown category. For each dog in the UTD-V and UTD-O categories, the time since last vaccination was recorded as < 1, 1 to 2, or 2 to 3 years.

The final diagnosis was recorded for each dog and was classified on the basis of major disease or organ system affected (cardiac, respiratory, renal, hepatic, endocrine, neurologic, neoplastic, gastrointestinal, inflammatory, autoimmune, septic, traumatic, or toxic). For dogs with > 1 disease process, the disease that warranted the patient's admission to the ICU was used as the classifying disease.

Statistical analysis

Descriptive data were generated for the study population. The serologic results for each dog were recorded as seropositive or seronegative, and the percentages of dogs that were seropositive and seronegative for CDV and CPV were calculated. The proportion of dogs that were seropositive for antibodies against CDV was compared with the proportion of dogs that were seropositive for antibodies against CPV by use of a χ2 analysis. For each virus, the relationship between a seropositive titer and the duration since last vaccination was also assessed with a χ2 test. Values of P < 0.05 were considered significant for all analyses.

Results

Dogs

Eighty dogs with ages ranging from 0.25 to 16.7 years (median, 8 years) were enrolled in the study. Various breeds were represented in the study population, with the most common being mixed-breed (n = 22 [27.5%]) and Labrador Retriever (12 [15%]). Of the 80 dogs in the study, 45 (56%) were castrated males, 28 (35%) were spayed females, 4 (5%) were sexually intact males, and 3 (4%) were sexually intact females. The primary disease process that warranted patient admission to the ICU was sepsis or infectious disease (n = 10 dogs), neoplasia (10), neurologic disease (9), respiratory tract disease (9), cardiac disease (9), gastrointestinal tract disease (9), renal disease (7), trauma (7), toxin exposure (4), autoimmune disease (3), and endocrine, inflammatory, and hepatic disease (1 each). Sixteen dogs had > 1 disease process recorded. One dog was being treated for CPV infection, which was confirmed by results of a CPV ELISA. That dog had an anti-CPV antibody titer of 1:81,920 and an anti-CDV antibody titer of 1:4, and had been vaccinated against CDV and CPV 4 days prior to hospital admission. The serum sample used for serologic analysis was collected > 7 days after hospital admission. That dog was hospitalized in the ICU for 20 days. Thirteen other study dogs were hospitalized in the ICU concurrently with the CPV-infected dog. The serum antibody titers for those 13 dogs ranged from 1:4 to 1:1,024 for CDV and from 1:80 to 1:40,960 for CPV; however, none of those patients developed signs of CPV infection while hospitalized.

Forty of the 80 (50%) dogs had anti-CDV antibody titers ≤ 1:30 and were classified as seronegative for CDV. Of those 40 dogs, 27 (67.5%) were classified in the UTD-V category, 9 (22.5%) were classified in the NUTD category, and the remaining 4 (10%) were classified in the unknown category. Of the 40 dogs that were seropositive for CDV, 27 (67.5%) were classified in the UTD-V category, 1 (2.5%) was classified in the UTD-O category, 4 (10%) were classified in the NUTD category, and the remaining 8 (20%) were classified in the unknown category.

Twelve of 80 (15%) dogs had anti-CPV antibody titers ≤ 1:80 and were classified as seronegative for CPV. Of those 12 dogs, 4 (33.3%) were classified in the UTD-V category, 5 (41.7%) were classified in the NUTD category, and 3 (25%) were classified in the unknown category. Of the 68 dogs that were seropositive for CPV, 50 (73.5%) were classified in the UTD-V category, 1 (1.5%) was classified in the UTD-O category, 9 (13.2%) were classified in the NUTD category, and 8 (11.8%) were classified in the unknown category. Ten dogs were seronegative for antibodies against both CDV and CPV. Of those dogs, 3 were classified in the UTD-V category, 1 was classified as UTD-O, 3 were classified in the NUTD category, and 3 were classified in the unknown category.

Collectively, 55 of the 80 (69%) dogs were considered up-to-date for vaccination against CDV and CPV. The number of those dogs that were seropositive and seronegative for each virus on the basis of duration since last vaccination was summarized (Table 1).

Table 1—

Number of dogs classified as up-to-date for vaccination against CDV and CPV that were seropositive and seronegative for antibodies against CDV and CPV on the basis of duration since last vaccination.

Duration since last vaccinationCDVCPV
SeropositiveSeronegativeSeropositiveSeronegative 
< 1 y1211221
1–2 y97151
2–3 y97142

The study population consisted of 80 dogs that were hospitalized in the ICU of a veterinary teaching hospital between February 1 and June 1, 2015, of which only 55 were classified as up-to-date for vaccination against CDV and CPV. Dogs with serum antibody titers > 1:32 and > 1:80 were considered seropositive for CDV and CPV, respectively.

The proportion of dogs seropositive for CPV was significantly (P < 0.001) greater than the proportion of dogs seropositive for CDV. Time since last vaccination was not significantly associated with the presence of antibody titers against either CDV or CPV. When dogs were categorized on the basis of primary disease process and serostatus for antibodies against both CDV and CPV (Table 2), dogs with sepsis, cardiopulmonary disease, and renal disease appeared to be seronegative for CDV and CPV more frequently than dogs with other disease processes, but the small number of dogs within each category precluded statistical analysis.

Table 2—

Classification of dogs on the basis of primary disease process and serostatus for antibodies against CDV and CPV.

Disease processNo. of dogsSeronegative for CDV and seropositive for CPVSeropositive for CDV and seronegative for CPVSeronegative for both CDV and CPVSeropositive for both CDV and CPV
Sepsis106022
Cardiac disease96012
Respiratory tract disease94032
Renal disease71033
Neurologic disease92007
Neoplasia103106
Gastrointestinal tract disease92115
Toxin exposure42002
Autoimmune disease32001
Endocrine disease10001
Inflammatory disease10001
Hepatic disease11000
Trauma71006

See Table 1 for key.

Discussion

Results of the present study indicated that, in this convenience sample of dogs hospitalized in an ICU, the proportion of dogs that were seropositive for antibodies against CDV and CPV (seropositive for CDV and CPV), 2 common viral pathogens for which vaccines are widely available, was lower than anticipated. Despite the fact that the majority (55/80 [69%]) of dogs in this study had received a multivalent vaccine against CDV and CPV within 3 years prior to being hospitalized and were considered up-to-date for vaccination against both diseases, 40 of the 80 (50%) dogs were seronegative for CDV and 12 (15%) were seronegative for CPV. That finding was striking and unanticipated given the high vaccination rate reported for pet dogs.

Results of other studies8,13–16 indicate that dogs may remain seropositive for CDV for 5 to 6 years after vaccination and seropositive for CPV for 4 to 9.5 years after vaccination. Canine populations examined include privately owned dogs, urban dogs, and dogs in shelters.9,17,18 In a study19 in which 327 privately owned dogs were evaluated for antibody titers against CPV, essentially all dogs had anti-CPV antibody titers that were considered protective against disease, the time since last vaccination ranged from 10 to 48 months, and the anti-CPV antibody titer was negatively associated with the time since last vaccination. In another study20 of 122 privately owned dogs that were examined prior to revaccination at the University of Missouri Veterinary Health Center, 89 (73%) had antibody titers that were considered protective against CPV and 96 (79%) had antibody titers that were considered protective against CDV. The results of the present study were somewhat similar to that population20 of healthy dogs that were revaccinated on the basis of perceived need. However, serologic data for dogs that are considered current on vaccinations on the basis of currently available guidelines are lacking because that population is generally assumed to be protected and serum antibody titers against vaccine antigens are rarely monitored. Additionally, although it might seem intuitive that the serum antibody titer would be negatively associated with the time since last vaccination, such a relationship was not observed in the present study, which suggested that time since last vaccination may not be a particularly important determinant for serum antibody titers against vaccine antigens.

To our knowledge, the present study was the first to evaluate serum anti-CDV and anti-CPV antibody titers in dogs hospitalized in an ICU. It is unclear whether critical illness affects the serum antibody titers against infectious pathogens. In another study,21 the serum antibody titers against CDV and CPV for vaccinated sled dogs increased over time as those dogs competed in the Iditarod, which might have been associated with the stress of racing and a heightened inflammatory response or exposure to pathogens. It is unknown whether critically ill dogs have a similar increase in antibody titers during the course of hospitalization and the attendant stressors of illness. For some dogs of the present study, serum was obtained and pooled from multiple blood samples that were collected at various times during hospitalization to accumulate a sufficient volume for evaluation.

It is unclear why the dogs of the present study were more likely to be seropositive for CPV than CDV, despite the fact that most were vaccinated with multivalent vaccines that contained antigens against both pathogens. One dog was infected with CPV and hospitalized in the ICU during the course of the present study. Exposure to that dog might have resulted in an increase in the anti-CPV antibody titers for some of the other study dogs. However, the CPV-infected dog was in the ICU for a short period, and it is unlikely exposure to that dog would have substantially affected the number of dogs that were seropositive for CPV. It is possible that the antigenicity of vaccines differed among manufacturers; unfortunately, the manufacturers of the vaccines administered to the dogs of this study were not uniformly recorded.

When an animal is vaccinated, a population of memory B cells is created that divides slowly for years. When that animal is subsequently exposed to a pathogen or other antigen against which it was vaccinated, that population of memory B cells expands and antibody is secreted. It is the population of memory B cells that determines survival after pathogen challenge. Measurement of memory B cells is impractical; therefore, serum antibody titers are measured and used as an indirect assessment of memory B cell populations, efficacy of vaccination, and response to pathogen challenge.9,11 Multiple studies have been conducted to determine the long-term protective immunity of healthy dogs that have been vaccinated against CDV and CPV and then subsequently challenged by those pathogens. Results of some studies14–16 indicate that 1 dose of a modified-live virus vaccine containing antigens of CDV and CPV administered to dogs at 16 weeks of age was sufficient to confer protection against disease caused by those pathogens. It is unclear whether critically ill dogs, such as those hospitalized in an ICU, are able to mount an immune response (as determined by an increase in serum antibody titer) when exposed to CDV or CPV.

One of the difficulties for any study that assesses vaccine titers is defining serologic protection. A patient with a high serum antibody titer against a particular pathogen is assumed to be protected against disease caused by that pathogen; however, serum antibody titers are only a surrogate for assessment of the immune response. A more perfect, but ethically less sound, assessment of the immune response involves challenging a subject with a particular antigen after vaccination. Challenge studies have been performed in various populations after vaccination, but those studies generally involve healthy animals that are housed in controlled experimental environments. A challenge study involving critically ill patients should not be undertaken, although measurement of serum antibody titers in patients with infectious diseases before and after treatment in an ICU could be considered an alternative for a controlled challenge study. In the absence of such natural or experimental challenge studies, measurement of a serum antibody titer against a vaccine pathogen at 1 point in time is simply a surrogate measure of a patient's immunologic milieu. It is possible that dogs with low or absent antibody titers against CDV and CPV are in fact immune to disease caused by those pathogens and that no evidence of systemic disease will result following exposure to CDV or CPV. Anecdotally, this fact is supported by the clinical experience of diplomates of the American College of Veterinary Emergency and Critical Care who report no nosocomial outbreaks of distemper or parvovirus in dogs hospitalized in an ICU.

Another factor complicating assessment of antibody titers in critically ill dogs is that such dogs may be immunosuppressed from diseases such as sepsis or drugs such as those used for the treatment of cancer or immune-mediated diseases. The effect of immunosuppression on a dog's ability to mount an antibody response to CDV or CPV is unknown. None of the dogs of the present study became clinically infected with CDV or CPV during the study, and to our knowledge, there has never been an ICU-associated outbreak of CDV or CPV in dogs. One puppy < 10 weeks old in the present study was being treated for severe traumatic brain injury and had not yet received the recommended full complement of CDV and CPV vaccines. That puppy received a multivalent vaccine at 8 weeks old 2 weeks prior to admission to the ICU, and it was seropositive for both CDV (titer, 1:384) and CPV (titer, 1:1,280).

Dogs infected with CDV or CPV may be critically ill. Proper care of those patients may necessitate them being hospitalized in an ICU that has sufficient full-time staffing rather than an isolation ward that has only intermittent staffing. Prior to the present study, we were relatively confident that most dogs hospitalized in the ICU have protective serum antibody titers against CDV and CPV; however, the results of this study have forced us to reevaluate that assumption. Additional studies involving canine populations larger than that evaluated in this study are necessary to better understand the risk of critically ill dogs acquiring CDV and CPV.

Strict infectious disease control guidelines should be followed when a CDV- or CPV-infected dog is treated in an ICU. We advocate the implementation of proper barrier measures and that nurses and doctors who treat CDV- or CPV-infected dogs not concurrently treat animals that are immunosuppressed or have an unknown vaccine status. Serum antibody titers against CDV and CPV could be measured for all dogs prior to ICU admission; however, that might be expensive and impractical given that it often takes several days for the results to become available, and patients admitted to the ICU require immediate care. Furthermore, serologic titers may not correlate well with the immune response to an infectious agent. Results of another study22 indicate that serum antibody titers against CDV and CPV determined by a point-of-care ELISA were accurate, compared with those determined by use of serum neutralization and hemagglutination inhibition assays, respectively. Results for the point-of-care ELISA are reported as positive or negative, and an antibody titer ≥ 1:16 is considered seropositive for CDV and an antibody titer ≥ 1:80 is considered seropositive for CPV.22 That ELISA has been evaluated in a population of shelter dogs,12 and results suggest that it could be beneficial for assessing the relative risk for patients hospitalized near CDV- or CPV-infected dogs.

In the present study, it was interesting that dogs with sepsis and cardiac disease tended to have lower serum antibody titers against CDV and CPV than dogs with other disease processes. The cause for that difference is unknown. Sepsis is characterized by both a systemic inflammatory and anti-inflammatory response. Sepsis is characterized by lymphocyte apoptosis23 and impaired humoral immunity in mice.24 The dogs with sepsis in the present study may have been unable to generate adequate antibody titers because of immunoparalysis, although other mechanisms might have also been at play.

Following vaccination against influenza, human patients with heart failure have lower serum antibody titers than healthy control patients, possibly because patients with heart failure have chronic activation of the sympathetic nervous system.25–27 Patients with heart failure have abnormally increased systemic concentrations of epinephrine and norepinephrine. Lymphocytes express β2-adrenergic receptors, and antibody production may be downregulated when those receptors are chronically stimulated. A similar mechanism could be responsible for the apparent decrease in serum anti-CDV and anti-CPV antibody titers observed for the dogs with sepsis and cardiac disease in the present study, but this is speculation only and further research is necessary.

The present study had several limitations. Serum antibody titers were measured only once (albeit some serum samples were pooled from blood samples collected at various times during hospitalization); therefore, it is unknown whether those titers were increasing or decreasing. Because it can take time for dogs to generate an antibody response, repeated measurement of serum antibody titers 2 to 4 weeks after hospitalization might have provided additional data regarding the immunologic milieu of each patient and greater confidence that dogs with low antibody titers had more active memory cell populations than titers measured at only 1 time led us to believe. Hospitalization of a CPV-infected dog in the ICU during the study might have altered the results of the present study because that dog might have exposed other study dogs to CPV, which could have stimulated production of anti-CPV antibodies in those dogs. The 13 dogs that were in the ICU concurrently with the CPV-infected dog had serum anti-CPV antibody titers that ranged from 1:80 to 1:40,960. Another weakness of this study was that the vaccination status of some dogs was unknown. Although every effort was made to obtain a complete medical history for all dogs, the vaccination history was unavailable for 13 dogs.

In the present study, the proportion of critically ill dogs that were seropositive for CDV and CPV was lower than expected. Although this study did not provide evidence that CDV and CPV were directly contagious in an ICU setting, we advocate the implementation of excellent isolation and barrier measures when CDV- or CPV-infected dogs are treated in an ICU in proximity to other critically ill dogs. Future research is necessary to assess serial anti-CDV and anti-CPV antibody titers of hospitalized dogs and the potential benefits of using a point-of-care ELISA for measurement of serum antibodies against CDV and CPV in dogs hospitalized in an ICU.

Acknowledgments

Supported by the Companion Animal Health Fund, Cummings School of Veterinary Medicine, Tufts University.

Presented as an abstract at the 21st International Veterinary Emergency and Critical Care Symposium, Washington, DC, September 2015.

ABBREVIATIONS

CDV

Canine distemper virus

CPV

Canine parvovirus

ICU

Intensive care unit

Footnotes

a.

Survey monkey. Infectious disease in SA ICU. Available at: www.surveymonkey.com/r/6LH8T3D. Accessed Oct 9, 2015.

References

  • 1 Martella V, Elia G, Buonavoglia C. Canine distemper virus. Vet Clin North Am Small Anim Pract 2008; 38: 787797.

  • 2 Lempp C, Spitzbarth I, Puff C, et al. New aspects of the pathogenesis of canine distemper leukoencephalitis. Viruses 2014; 6: 25712601.

  • 3 Ek-Kommonen C, Sihvonen L, Pekkanen K, et al. Outbreak of canine distemper in vaccinated dogs in Finland. Vet Rec 1997; 141: 380383.

  • 4 Beineke A, Puff C, Seehusen F, et al. Pathogenesis and immunopathology of systemic and nervous canine distemper. Vet Immunol Immunopathol 2009; 127: 118.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 5 Savigny MR, Macintire DK. Use of oseltamivir in the treatment of canine parvoviral enteritis. J Vet Emerg Crit Care (San Antonio) 2010; 20: 132142.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 6 Prittie J. Canine parvoviral enteritis: a review of diagnosis, management, and prevention. J Vet Emerg Crit Care 2004; 14: 167176.

  • 7 Goddard A, Leisewitz AL. Canine parvovirus. Vet Clin North Am Small Anim Pract 2010; 40: 10411053.

  • 8 Olson P, Finnsdóttir H, Klingeborn B, et al. Duration of antibodies elicited by canine distemper virus vaccinations in dogs. Vet Rec 1997; 141: 654655.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 9 Jóźwik A, Frymus T, Mizak B, et al. Antibody titres against canine distemper virus in vaccinated and unvaccinated dogs. J Vet Med B Infect Dis Vet Public Health 2004; 51: 99103.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 10 American Animal Hospital Association (AAHA) Canine Vaccination Task Force, Welborn LV, DeVries JG, et al. 2011 AAHA canine vaccination guidelines. J Am Anim Hosp Assoc 2011; 47: 142.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 11 Mitchell SA, Zwijnenberg RJ, Huang J, et al. Duration of serological response to canine parvovirus-type 2, canine distemper virus, canine adenovirus type 1 and canine parainfluenza virus in client-owned dogs in Australia. Aust Vet J 2012; 90: 468473.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 12 Gray LK, Crawford PC, Levy JK, et al. Comparison of two assays for detection of antibodies against canine parvovirus and canine distemper virus in dogs admitted to a Florida animal shelter. J Am Vet Med Assoc 2012; 240: 10841087.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 13 Wilson S, Illambas J, Siedek E, et al. Vaccination of dogs with canine parvovirus type 2b (CPV-2b) induces neutralising antibody responses to CPV-2a and CPV-2c. Vaccine 2014; 32: 54205424.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 14 Schultz RD. Duration of immunity for canine and feline vaccines: a review. Vet Microbiol 2006; 117: 7579.

  • 15 Schultz RD, Scott FW. Canine and feline immunization. Vet Clin North Am 1978; 8: 755768.

  • 16 Schultz RD, Thiel B, Mukhtar E, et al. Age and long-term protective immunity in dogs and cats. J Comp Pathol 2010; 142 (suppl 1): S102S108.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 17 Lechner ES, Crawford PC, Levy JK, et al. Prevalence of protective antibody titers for canine distemper virus and canine parvovirus in dogs entering a Florida animal shelter. J Am Vet Med Assoc 2010; 236: 13171321.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 18 Litster A, Nichols J, Volpe A. Prevalence of positive antibody test results for canine parvovirus (CPV) and canine distemper virus (CDV) and response to modified live vaccination against CPV and CDV in dogs entering animal shelters. Vet Microbiol 2012; 157: 8690.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 19 Larson LJ, Schultz RD. Three-year serologic immunity against canine parvovirus type 2 and canine adenovirus type 2 in dogs vaccinated with a canine combination vaccine. Vet Ther 2007; 8: 305310.

    • Search Google Scholar
    • Export Citation
  • 20 McCaw DL, Thompson M, Tate D, et al. Serum distemper virus and parvovirus antibody titers among dogs brought to a veterinary hospital for revaccination. J Am Vet Med Assoc 1998; 213: 7275.

    • Search Google Scholar
    • Export Citation
  • 21 Banse HE, McKenzie EC, Nelson S, et al. Assessment of serum antibody titers against canine distemper virus, canine adenovirus type II, and canine parvovirus in Alaskan sled dogs before and after a long-distance race. J Am Vet Med Assoc 2008; 232: 16691673.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 22 Litster AL, Pressler B, Volpe A, et al. Accuracy of a point-of-care ELISA test kit for predicting the presence of protective canine parvovirus and canine distemper virus antibody concentrations in dogs. Vet J 2012; 193: 363366.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 23 Heidecke CD, Hensler T, Weighardt H, et al. Selective defects of T lymphocyte function in patients with lethal intraabdominal infection. Am J Surg 1999; 178: 288292.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 24 Pötschke C, Kessler W, Maier S, et al. Experimental sepsis impairs humoral memory in mice. PLoS One 2013; 8: e81752.

  • 25 Albrecht CM, Sweitzer NK, Johnson MR, et al. Lack of persistence of influenza vaccine antibody titers in patients with heart failure. J Card Fail 2014; 20: 105109.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 26 Vardeny O, Moran JJ, Sweitzer NK, et al. Decreased T-cell responses to influenza vaccination in patients with heart failure. Pharmacotherapy 2010; 30: 1016.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 27 Vardeny O, Sweitzer NK, Detry MA, et al. Decreased immune responses to influenza vaccination in patients with heart failure. J Card Fail 2009; 15: 368373.

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