Clinical and molecular epidemiology of veterinary blastomycosis in Wisconsin

BMC Veterinary Research

Jennifer K Meece²  Brian L Sloss¹  Jennifer L Anderson² 

[1] U.S. Geological Survey, Wisconsin Cooperative Fishery Research Unit, College of Natural Resources, University of Wisconsin-Stevens Point, Stevens Point WI 54481, USA;Marshfield Clinic Research Foundation, Marshfield WI 54449, USA

关键词: Genetics;    Blastomyces dermatitidis;    Epidemiology;    Canine;    Blastomycosis;   

Others  :  1119554
DOI  :  10.1186/1746-6148-9-84

 received in 2012-11-21, accepted in 2013-04-16,  发布年份 2013

【 摘 要 】

Background

Several studies have shown that Blastomyces dermatitidis, the etiologic agent of blastomycosis, is a genetically diverse pathogen. Blastomycosis is a significant health issue in humans and other mammals. Veterinary and human isolates matched with epidemiological case data from the same geographic area and time period were used to determine: (i) if differences in genetic diversity and structure exist between clinical veterinary and human isolates of B. dermatitidis and (ii) if comparable epidemiologic features differ among veterinary and human blastomycosis cases.

Results

Genetic typing of 301 clinical B. dermatitidis isolates produced 196 haplotypes (59 unique to veterinary isolates, 134 unique to human isolates, and 3 shared between canine and human isolates). Private allelic richness was higher in veterinary (median 2.27) compared to human isolates (median 1.14) (p = 0.005).

Concordant with previous studies, two distinct genetic groups were identified among all isolates. Genetic group assignment was different between human and veterinary isolates (p < 0.001), with more veterinary isolates assigned to Group 2.

The mean age of dogs diagnosed with blastomycosis was 6 years. Thirty cases were in male dogs (52%) and 24 were females (41%). The breed of dog was able to be retrieved in 38 of 58 cases with 19 (50%) being sporting breeds. Three of four felines infected with blastomycosis were domestic shorthair males between ages 6–12, and presented with disseminated disease. The other was a lynx with pulmonary disease. The equine isolate was from an 11-year-old male Halflinger with disseminated disease. Disseminated disease was reported more often in veterinary (62%) than human cases (19%) (p < 0.001).

Conclusions

Isolates from all hosts clustered largely into previously identified genetic groups, with 3 haplotypes being shared between human and canine isolates confirming that B. dermatitidis isolates capable of infecting both species occur in nature. Allelic diversity measures trended higher in veterinary samples, with a higher number of total alleles and private alleles. Veterinary isolates of B. dermatitidis contributed a substantial amount of diversity to the overall population genetic structure demonstrating the importance of including veterinary isolates in genetic studies of evolution and virulence in this organism.

【 授权许可】

   
2013 Anderson et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

【 参考文献 】

• [1]Furcolow ML, Chick EW, Busey JF, Menges RW: Prevalence and incidence studies of human and canine blastomycosis. 1. Cases in the United States, 1885–1968. Am Rev Respir Dis 1970, 102:60-67.
• [2]Archer JR, Trainer DO, Schell RF: Epidemiologic study of canine blastomycosis in Wisconsin. J Am Vet Med Assoc 1987, 190:1292-1295.
• [3]Rudmann DG, Coolman BR, Perez C, Glickman LT: Evaluation of risk factors for blastomycosis in dogs: 857 cases (1980–1990). J Am Vet Med Assoc 1992, 201:1754-1759.
• [4]Arceneaux KA, Taboada J, Hosgood G: Blastomycosis in dogs: 115 cases (1980–1995). J Am Vet Med Assoc 1998, 213:658-664.
• [5]Minnesota Department of Health, Blastomycosis Statistics and Maps. http://www.health.state.mn.us/divs/idepc/diseases/blastomycosis/statistics.html webcite
• [6]Menges RW, Doto IL, Weeks RJ: Epidemiologic studies of blastomycosis in Arkansas. Arch Environ Health 1969, 18:956-971.
• [7]Baumgardner DJ, Paretsky DP, Yopp AC: The epidemiology of blastomycosis in dogs: north central Wisconsin, USA. J Med Vet Mycol 1995, 33:171-176.
• [8]Brömel C, Sykes JE: Epidemiology, diagnosis, and treatment of blastomycosis in dogs and cats. Clin Tech Small Anim Pract 2005, 20:233-9.
• [9]Gilor C, Graves TK, Barger AM, O'Dell-Anderson K: Clinical aspects of natural infection with Blastomyces dermatitidis in cats: 8 cases (1991–2005). J Am Vet Med Assoc 2006, 229:96-9.
• [10]Yates-Siilata KE, Sander DM, Keath EJ: Genetic diversity in clinical isolates of the dimorphic fungus Blastomyces dermatitidis detected by a PCR-based random amplified polymorphic DNA assay. J Clin Microbiol 1995, 33:2171-2175.
• [11]McCullough MJ, DiSalvo AF, Clemons KV, Park P, Stevens DA: Molecular epidemiology of Blastomyces dermatitidis. Clin Infect Dis 2000, 30:328-335.
• [12]Meece JK, Anderson JL, Klein BS, Sullivan TD, Foley SL, Baumgardner DJ, Brummitt CF, Reed KD: Genetic Diversity in Blastomyces dermatitidis: Implications for PCR Detection in Clinical and Environmental Samples. Med Mycol 2010, 48:285-290.
• [13]Meece JK, Anderson JL, Fisher MC, Henk DA, Sloss BL, Reed KD: Population Genetic Structure of Clinical and Environmental Isolates of Blastomyces dermatitidis based on 27 Polymorphic Microsatellite Markers. Appl Environ Microbiol 2011, 17:5123-5131.
• [14]Meece JK, Anderson JL, Gruszka S, Sloss BL, Sullivan B, Reed KD: Variation in clinical phenotype of human infection among genetic groups of Blastomyces dermatitidis. J Infect Disease 2013, 207:814-822.
• [15]Baumgardner DJ, Paretsky DP: Identification of Blastomyces dermatitidis in the stool of a dog with acute pulmonary blastomycosis. J Med Vet Mycol 1997, 35:419-421.
• [16]Leberg PL: Estimating allele richness: Effects of sample size and bottlenecks. Mol Ecol 2002, 11:2445-2449.
• [17]Kalinowski ST: Counting alleles with rarefaction: Private alleles and hierarchical sampling designs. Conserv Genet 2004, 5:539-543.
• [18]Kalinowski ST: HP-Rare: a computer program for performing rarefaction on measures of allelic diversity. Mol Ecol Notes 2005, 5:187-189.
• [19]Peakall R, Smouse PE: GENALEX 6: genetic analysis in Excel. Population genetic software for teaching and research. Mol Ecol Notes 2006, 6:288-295.
• [20]Pritchard JK, Stephens M, Donnelly P: Inference of population structure using multilocus genotype data. Genetics 2000, 155:945-959.
• [21]Evanno G, Regnaut S, Goudet J: Detecting the number of clusters of individuals using the software STRUCTURE: a simulation study. Mol Ecol 2005, 14:2611-2620.
• [22]Earl DA: vonHoldt BM: STRUCTURE HARVESTER: a website and program for visualizing STRUCTURE output and implementing the Evanno method . Conserv Genet Resour 2012, 2:359-361.
• [23]Koufopanou V, Burt A, Taylor JW: Concordance of gene genealogies reveals reproduction isolation in the pathogenic fungus Coccidioides immitis. Proc Natl Acad Sci 1997, 94:5478-5482.
• [24]Fisher MC, Hanage WP, de Hoog S, Johnson E, Smith MD, White NJ, Vanittanakom N: Low Effection Dispersal of Asexual Genotypes in Heterogeneous Landscapes by the Endemic Pathogen Penicillium marneffei. PLoS Pathog 2005, 2:e20.
• [25]Wenjun L, Sullivan TD, Walton E, Averette AF, Sakthikumar S, Cuomo CA, Lein BS, Heitman J: Identification of the Mating-Type (MAT) Locus That Controls Sexual Reproduction of Blastomyces dermatitids. Eukaryot Cell 2013, 12:109-117.
• [26]Reed KD, Meece JK, Archer JR, Peterson AT: Ecologic niche modeling of Blastomyces dermatitidis in Wisconsin. PLoS One 2008, 4:e2034.
• [27]Klein BS, Vergeront JM, DiSalvo AF, Kaufman L, Davis JP: Two outbreaks of blastomycosis along rivers in Wisconsin. Isolation of Blastomyces dermatitidis from riverbank soil and evidence of its transmission along waterways. Am Rev Respir Dis 1987, 6:1333-1338.
• [28]Denton JF, DiSalvo AF: Additional isolations of Blastomyces dermatitidis from natural sites. Am J Trop Med Hyg 1979, 28:697-700.
• [29]Baumgardner DJ, Paretsky DP, Baeseman ZJ, Schreiber A: Effects of season and weather on blastomycosis in dogs: Northern Wisconsin, USA. Med Mycol 2011, 49:49-55.