Lonnie GonsalvesNOAA Cooperative Oxford Laboratory

IntroductionGenus Description: TB vs. EMMicrobial ecologyPathogenic mycobacteria in fishThe Chesapeake StoryFish impactsHuman impactsContinued research

Tuberculosis ComplexM. tuberculosis, M. bovis, M. africanum, M. caprae, M. canettii, M. pinnipedii, and M. microtiM. leprae

Environmental MycobacteriaOver 120 species outside of TB complex and M. lepraeAerobic, gram positive, acid-fast, non-motile, saprophytic Diverse environments:Marine and fresh water, treated municipal water, industrial hot water systems, hot tubs Multiple vectors: Insects, protozoa, amoebaExtremely hardyChemical resistantBiofilm formationPrimarily non-pathogenic

Pathogenic Mycobacteria in Fish160+ fish species susceptible to infectionAquaria, aquaculture, and wild fish

Fishbase.orgFishbase.org

External lesionsEmaciationPigment changesVisceral red fociPop eyeEnlarged/granular spleenGranuloma*Inter-specific variation in virulence and host response*

Macrophages: Home Sweet HomeIntracellular survivalROS/chemical-resistant cell wallPrevent phago-lysosome maturationAlter inflammatory responseGranuloma formation

Co et al. 2004

Routes of TransmissionIngestion (Harriff, Bermudez, and Kent 2007)Water column (Li and Gatlin 2005)Open woundsAttachment of amoebaTransovarian (Conroy 1966)

Mycobacteriosis in the Chesapeake BayOutbreak of dermal lesions in 1997Attention from multiple research groupsVIMSCOLUMD-College ParkMD DNRMycobacterium spp. causative agent (Heckert et al. 2001; Rhodes et al. 2001)Age dependent infection rates (Kaatari et al. 2005)Prevalence > 70% in older fishM. shottsii primary isolate in striped bassDetected in archived tissues 1984 (Jacobs et al. 2009)

Prevalence over time

Chart1

19985.918.3326.4235.3

199911.772129.539.4

200017.6535.938.144.83

200127.2721.0544.4462.5

2019.0538.0444.1244.44

9.6219.6634.624860

9.0213.1837.544.5980.77

19.9132.1637.7558.3366.1

26.9244.4447.7355.0851.43

35.8943.3850.9847.1864.36

44.8642.3352.1761.971.83

Mark Matsche, Maryland Department of Natural Resources

Age 1

Age 2

Age 3

Age 4

Age 5

Year

Prevalence (%)

Sheet1

YearAgepercentpNCI

199825.90.059172.7166142066

1998318.330.183601.2631106418

1998426.420.2641060.8150628086

1998535.30.353342.7549685622

1999200310

19993210.21860.9282838892

1999429.50.295881.0157316044

1999539.40.394332.9021947656

2000217.650.176174.3906325198

2000335.90.359781.2054180982

2000438.10.381631.5108569067

2000544.830.448293.360985349

2001227.270.272223.9644553616Age19981999200020012002200320042005200620072008

2001321.050.21571.40056867491209.629.0219.9126.9235.8944.86

2001444.440.444541.803396375125.911.7717.6527.2719.0519.6613.1832.1644.4443.3842.33

2001562.50.625165.9305057489318.332135.921.0538.0434.6237.537.7547.7350.9852.17

20021200.2155.2266666667426.4229.538.144.4444.124844.5958.3355.0847.1861.9

2002219.050.19213.6614751126535.339.444.8362.544.446080.7766.151.4364.3671.83

2002338.040.38921.0340841633

2002444.120.441681.4311078282

2002544.440.444273.6067927501

200319.620.096521.1103823746

2003219.660.1961170.6650070809

2003334.620.346521.7929973648

20034480.48253.9168627446

20035600.6109.6019997917

200419.020.091330.4217415417

2004213.180.1311290.5126393001

2004337.50.375322.9652528744

2004444.590.446741.3165782109

2004580.770.807262.9750765531

2005116.910.171360.5413531521

2005232.160.3212550.3588420213

2005337.750.3772490.3814796914

2005458.330.583128.0533603131

20055100140

2006126.920.27521.6733856479

2006244.440.4441260.7728841607

2006347.730.4772200.444983005

2006455.080.552360.4131727493

2006551.430.514352.7989021848

2007350.980.51511.9211842753

2007447.180.4721950.5017754633

2007564.360.6431010.9297673517

2008144.860.4481070.9109212628

2008242.330.4231630.5940548655

2008352.170.521462.1285549097

2008461.90.621470.6471819253

2008571.830.718711.2421799039

Sheet1

Age 1

Age 2

Age 3

Age 4

Age 5

Year

Prevalence

Sheet2

Sheet3

Mycobacteriosis in Striped Bass by Age1998-presentMark Matsche, Maryland Department of Natural Resources

Collected in the Chesapeake Bay 1999-2001

Prevalence of lesions in wild-caught striped bass (Overton et al. 2003)

Kane et al. 2007

Impact on FisheryRise in natural mortality during ongoing epizootic (Crecco 2003; Kahn 2004; Jiang et al. 2007)Increased estimates of myco.-induced mortality (Gauthier et al. 2008)Ubiquitous, not novel

Why Now?NutritionReduced growthChanges in foraging behavior

Why Now?NutritionReduced growthChanges in foraging behaviorWater qualityNutrientsHypoxiaAffect on alternate fish species

Impact on the Human HealthDiseased fish less marketableHuman health risk?Consumption of striped bass is NOT considered a disease riskAssociated with handling fish/water contact

www.dnr.state.md.us/dnrnews/infocus/striped_bass_health.asp

ConclusionMycobacterium spp. infection increased 1997-2004Increased natural mortality within time frameSlow deathRelatively low risk of human infection IF proper precautions consideredImpact on other key fish stocks?Factors contribute to disease prevalence?

Questions?

Shows progression of disease as age increases.No significant difference between males and females .