Risk Factors Associated with Risk Factors Associated with Porcine Cysticercosis Porcine Cysticercosis

Prevalence in Smallholder Pig Prevalence in Smallholder Pig Production Systems In Mbeya Production Systems In Mbeya Region, Southern Highland Of Region, Southern Highland Of

TanzaniaTanzania

ByBy

E.C. Kimbi1E.C. Kimbi1, , S.M. Thamsborg, S.M. Thamsborg, F.P. F.P. Lekule, J. MlangwaLekule, J. Mlangwa and E. Kombaand E. Komba

October 25-28, 2010October 25-28, 2010

Background InformationBackground Information

• Pig production trend in Africa (FAOSTAT, 2009)Pig production trend in Africa (FAOSTAT, 2009)– Pig production has shown a considerable growing trend across Pig production has shown a considerable growing trend across

different African regions, with exception of Northern Africa different African regions, with exception of Northern Africa

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1000 tonnes)

East AfricaMiddle AfricaNorth AfricaSouth AfricaWest Africa

Pork production trend in Pork production trend in Tanzania (FASTAT, 2009)Tanzania (FASTAT, 2009)• It is fastest growing livestock sub-It is fastest growing livestock sub-

sector in Tanzaniasector in Tanzaniay = 3.5102x2 + 104.13x + 1944.3

R2 = 0.9484

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10000

12000

14000

16000

year

po

rk p

rod

ucti

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pork prod(tonne)

Poly. (porkprod (tonne))

Pig production in TanzaniaPig production in Tanzania

• Pig production in Tanzania is predominantly Pig production in Tanzania is predominantly (94%) carried out by smallholder farmers (94%) carried out by smallholder farmers under low input-output production systemsunder low input-output production systems

• It involve over 7 % of the smallholder It involve over 7 % of the smallholder farmers and 18 % of livestock keeping farmers and 18 % of livestock keeping householdshouseholds

• Consequently, the sub-sector has increased Consequently, the sub-sector has increased the availability and consumption of pork in the availability and consumption of pork in rural and urban families rural and urban families

• However, the predominance of smallholder However, the predominance of smallholder systems, and increased pork consumption systems, and increased pork consumption have resulted to emergency and widening of have resulted to emergency and widening of diseases, particularly porcine cysticercosis (PC)diseases, particularly porcine cysticercosis (PC)

• Limited studies in TZ have indicated alarming Limited studies in TZ have indicated alarming

state for PC prevalencestate for PC prevalence– i.e. Mbulu (17 %), Chunya (5.5%,), Mbozi (32%), i.e. Mbulu (17 %), Chunya (5.5%,), Mbozi (32%),

Mbeya rural (30.7%)Mbeya rural (30.7%)– Human cysticercosis Mbozi 16.7 & 45.3 % for active Human cysticercosis Mbozi 16.7 & 45.3 % for active

and exposure respectivelyand exposure respectively

• PC is an important parasitic zoonosis, affecting PC is an important parasitic zoonosis, affecting human and pigs, caused by the infection with human and pigs, caused by the infection with the larval (metacestode) stage of the tapeworm the larval (metacestode) stage of the tapeworm Taenia soliumTaenia solium

• PC in Tanzania has become a barrier to PC in Tanzania has become a barrier to local, regional, and international trading local, regional, and international trading of pigs and pork of pigs and pork

• However, there was no adequate However, there was no adequate information on the risk factors associated information on the risk factors associated to the prevalence of this disease for to the prevalence of this disease for developing effective control strategiesdeveloping effective control strategies

• Therefore, the current study was Therefore, the current study was conducted to determine risk factors for PC conducted to determine risk factors for PC in order to develop sustainable strategies in order to develop sustainable strategies for control for control

MATERIALS AND METHODSMATERIALS AND METHODS• Study area: Study area:

– MbeyaMbeya and and MboziMbozi districts located in districts located in Mbeya regionMbeya region in Southern in Southern Highlands of TanzaniaHighlands of Tanzania (SHT)(SHT)

• Study design and sampling proceduresStudy design and sampling procedures

– Cross sectional survey designCross sectional survey design was conducted was conducted between Nov 2007 and Jan 2008between Nov 2007 and Jan 2008

– A multistage sampling techniqueA multistage sampling technique was used to sample was used to sample

villages, households, and pigsvillages, households, and pigs

– 30 villages30 villages were randomly sampled from sample were randomly sampled from sample frame of villages keeping pigs in the study districtsframe of villages keeping pigs in the study districts

– 300 pig-keeping households300 pig-keeping households were randomly sampled were randomly sampled

from the selected villages from the selected villages

• Sequentially, 300 pigs per district were Sequentially, 300 pigs per district were sampled based on Martin sampled based on Martin et alet al. (1987) . (1987) formula formula

• Data collectionData collection – Data at household level were collected using Data at household level were collected using

structured questionnairestructured questionnaire

– Concurrently, pig blood samples for serology Concurrently, pig blood samples for serology were collected from respective households were collected from respective households

– An ELISA detecting circulating An ELISA detecting circulating T. soliumT. solium antigens (Ag-ELISA) was performed as antigens (Ag-ELISA) was performed as described by Brandt described by Brandt et alet al. (1992) and . (1992) and modified by Dorny modified by Dorny et alet al. (2004) . (2004)

Statistical analysisStatistical analysis

• Data on pig seroprevalence and risk Data on pig seroprevalence and risk factors were analysed using STATA factors were analysed using STATA version 10version 10

• A multivariate logistic regression analysis A multivariate logistic regression analysis was then done, calculating OR and CI was then done, calculating OR and CI (95%) risk factors (95%) risk factors

• A household was considered PC A household was considered PC prevalence +ve when at least one pig prevalence +ve when at least one pig was found infected using Ag-ELISAwas found infected using Ag-ELISA

RESULTSRESULTS

•Household level PC prevalenceHousehold level PC prevalence

– Ag-ELISA results showed that all Ag-ELISA results showed that all study villages were PC infected study villages were PC infected with varying magnitudewith varying magnitude

– Households PC prevalence across Households PC prevalence across villages varied between 10 and villages varied between 10 and 90% with mean of 45.3% 90% with mean of 45.3%

Risk factors for PC in pig Risk factors for PC in pig keepers’ householdskeepers’ households

• Pig management systems and Pig management systems and practicespractices– Semi confinement (SC) and Total Confinement Semi confinement (SC) and Total Confinement

(TC) were the dominant pig management (TC) were the dominant pig management systems practised by 49.3 and 42.0 % of pig systems practised by 49.3 and 42.0 % of pig keepers’ households, respectivelykeepers’ households, respectively

– Few (8.7 %) pig keepers practiced Free range Few (8.7 %) pig keepers practiced Free range

and or herding (FRH)and or herding (FRH)

– PC prev were significantly (OR = 2.1, P < 0.01) PC prev were significantly (OR = 2.1, P < 0.01) higher in both households practicing SC and higher in both households practicing SC and FRH systems than those practising TC. FRH systems than those practising TC.

– Three main types of pig shelters were used by pig Three main types of pig shelters were used by pig keepers; slatted raised floor, earthen floor and keepers; slatted raised floor, earthen floor and concrete floorconcrete floor

– PC prev. was significantly (OR = 8.4, P < 0.05) higher PC prev. was significantly (OR = 8.4, P < 0.05) higher for households with for households with slatted raised floorslatted raised floor than those than those with with earthed floorearthed floor and and concrete floorconcrete floor

• pig keeping experience and past pig keeping experience and past experience of PC in the pig herdexperience of PC in the pig herd

– Past experience of PC in the pig herd was a Past experience of PC in the pig herd was a significant risk factor (OR = 2.6, P< 0.01) significant risk factor (OR = 2.6, P< 0.01)

– However, long or short experience in pig keeping had However, long or short experience in pig keeping had no significant influence on PC prevalence in the no significant influence on PC prevalence in the household (P>0.05) household (P>0.05)

• Hygienic factors: Latrine and water useHygienic factors: Latrine and water use

– Presence or absence of latrine had no significant Presence or absence of latrine had no significant effects on PC prevalence in the households (P > effects on PC prevalence in the households (P > 0.05)0.05)

– PC prev. were significantly higher for households PC prev. were significantly higher for households

sourcing water from sourcing water from riversrivers than their counterparts than their counterparts sourcing from sourcing from tap water, borehole and springstap water, borehole and springs (OR (OR = 3.1, P < 0.001) = 3.1, P < 0.001)

– Similarly, use of water from ponds significantly Similarly, use of water from ponds significantly increased the risk for PC as compared to tap water, increased the risk for PC as compared to tap water, water from springs and boreholes (OR = 5.0, P < water from springs and boreholes (OR = 5.0, P < 0.05) 0.05)

Conclusion and Conclusion and recommendationsrecommendations • The study revealed clearly that PC is endemic in The study revealed clearly that PC is endemic in

the study area. the study area.

• This observation validates the existence of This observation validates the existence of T. T. soliumsolium carriers in the study area who have carriers in the study area who have contaminated the environment with contaminated the environment with T. soliumT. solium eggs.eggs.

• Integrated approaches and cost-effective Integrated approaches and cost-effective

combination of simple interventions are combination of simple interventions are recommended for effective control of PC/taeniosis recommended for effective control of PC/taeniosis i.e. i.e.

– Health education campaign Health education campaign – Promotion of suitable pig management systemsPromotion of suitable pig management systems– development of suitable and hygiene pig marketing development of suitable and hygiene pig marketing

system system

AcknowledgementsAcknowledgements

• We greatly thank the Danish We greatly thank the Danish International Development Agency International Development Agency (DANIDA), through the Cysticercosis in (DANIDA), through the Cysticercosis in Eastern and Southern Africa (CESA) - Eastern and Southern Africa (CESA) - project for funding this study. project for funding this study.