“Workshop: In-depth smallholder pig value chain assessment and preliminary identification of best-bet interventions, Kampala, 9-11 April 2013”

Diseases of economic and zoonotic importance in pig farming in Uganda: Control practices, successes, failures

and the way forward

Zachary Nsadha

The drives for pig farming; Pig farming and consumption of pork is on the

increase (Waiswa et al 2007, Ampaire and Rothchild 2010)

There is deliberate effort by Govnt, NGO eg Vedeco to support pig farming as an enterprise (MAAIF policy 2004, www.naads.or.ug)

MERITS FOR PIG AS AN ENTERPRISE FOR THE POOR

Can multiply very quickly ; capable of 6-10 viable piglets per furrowing, can have 2 viable furrowing per year.

Can grow to market size in a short time; 5-6 months a pig can be ready for market slaughter

Can thrive in low-in-put systems; it is omnivorous, complete scavenger to the extent of being coporophagic

in the rural setting, most of the pigs are kept by the small holder at free range system

DISADVANTAGES OF KEEPING PIGS AT FREE RANGE PIG

Pigs are at high risk of acquiring of diseases. production limiting, such as the helminths Ascaris suis and

Trichuris suis (Stewart and Hale, 1988, Nansen and Roepstorff, 1999)

the highly pathogenic (fatal) virus causing African swine fever (Bengis et al., 2002),

have serious public health consequences,

(a) Cysticercosis caused by the zoonotic helminth Taenia solium (Pondja et al., 2010, Sikasunge et al., 2007

(b) Trichenellosis (Schuppers et al., 2010),

(c) Toxoplasmosis (van der Giessen et al., 2007)

IMPORTANT DISEASES TO PIG FARMING IN UGANDA

African swine fever: very pathogenic and fatal causing a lot of mortalities

Porcine cysticercosis: A zoonotic disease causing loss of income and devastating disease in the human (neurocysticercosis)

Intestinal Worms: cause retarded growth and poor returns from the pig enterprise.

Ectoparasites and mange: retarded growth in young ones

PORCINE CYSTICERCOSIS IN UGANDA

Porcine cysticercosis is a confirmed disease entity in Uganda Slaughter slab surveys: in Moyo district;33.5%, 34.1%

and 44.9% for Moyo town council, Moyo and Metu sub-counties respectively (Anyanzo, 1999).

Wambizi pig abattior 9.4% (Kisakye and Masaba 2002) 42 % sero-prevalence at Wambizi (unpublished information )

Field surveys: 8.9% (Ag ELISA) in Kamuli and Kaliro (Waiswa et al, 2009) , 9.4%, 7.7%, 8.2%, 6.9%, 0%, 12.9% and 4.1% (lingual )

Oyam, Apac, amolator, Kaberamaido, Kayunga, Kamuli and Kaliro (Nsadha et al 2010).

(AgELISA) 27%, 11%, 14.2% and 15% Arua, Busia, Kibale and Masaka to be respectively (Nsadha et al, 2011).

RISK FACTORS FOR ACQUISITION OF PORCINE CYSTICERCOSIS

1. PIG HUSBANDRY PRACTICES Intensive pig keeping is 2% of pigs in schools and religious

institutions The mode of keeping pigs depends on the crop season. In the

Lake Kyoga basin, During planting and growing, there is restriction during the day and most pigs are tethered on to pastures.

80% of the pigs are under the intermittence of free range and tethering. During fallowing almost all pigs are at free range all the time (Nsadha et al 2010)

In soroti distrcit 48% of the pigs were under the tethering, 46% were at free range and only 6% were kept intensively (Ziruntunda 2011)

Tethering of pigs is done to the bushes where open –air defecation is carried out by humans thus pigs can feed on infected materials

2. PRACTICES OF THE REGULATORY AUTHORITIES IN LIVESTOCK MARKETS

Pigs diagnosed positive (lingual cysts) are rejected by the inspector sale of such pigs is not allowed in the market the affected farmers are advised to take back the pigs to their homes (ochero and awelo livestock markets). The farmers whose pigs were rejected were observed to take away their pigs very quickly before fellow community members can get to know about the rejection.

Clandestine sale/slaughter is the likely fate of such pigs

3. LACK OF PORK INSPECTION DURING CLANDESTINE SLAUGHTER.

90% of the pork sold in the villages is not inspected (Nsadha et al 2010). Clandestine slaughters in ungazzted places makes it hard for vet. personnel to follow the slaughters (Dr. Kyokwijuka personal communication).

human taeniosis infections are very much likely

4. Lack of enforceable legislations for destruction of infected pigs; Sale of infected pigs with the communities is a common occurence.

the ‘let me not make loss voice’ rides the day in the communities5. Poor conceptions/perceptions among the communities Only 12 % of the respondent knew that pigs get infected by eating human

feaces. Only 16 % knew that humans get infected by eating infected pork. Because of ignorance, Communities can not practice preventative measures

to limit transmission of infections to pigs/humans.

self evaluation and preventative measures are key to disease prevention in communities

The “sieve” at wambizi is likely to be very porous

6. Poor pork inspection practices at slughter places

7. Improper human feaces disposal

In the rural settings of Uganda, 20% of the households lack toilet facilities (UBOS Report 2002).Soroti District 54% of the households do not have latrines (Zirintunda 2011).Poor commitment to use latrine is a common occurrence , 38% in Adumi S/C (Arua) of the latrines were not being used ie lacked indicators of latrine use

There is a lot of open-air defecation in the rural communities in Uganda

8. Poor handling of pigs and pork

(a) Very unhygienic handling of pigs/pork at slaughter expose to all sorts of contamination

(b)Poor cooking is determined by some factors; (i) demand of the day; the higher the demand the less

concentration to cook properly. (ii)the fuel source available; very poor fuel to give enough heat. (iii)the state of consciousness of the consumers ; most of the pork

in the rural areas is eaten at drinking points. The seller may release poorly cooked pork to the drunk customers or those in transit who are in a hurry.

under cooking is common in most of the rural pork joints and those pork roasting areas along the road side of international trade routes-transmission to humans

9. SOURCES OF WATER FOR DOMESTIC AND ANIMAL USE.

. In the rural Uganda 44% of the households do not have access to safe water (UBOS, population and housing census 2002).

. In the Lake Kyoga basin, 60% of the households fetch only drinking water from boreholes. Most of other water for doemastic use comes from unsafe sources (Nsadha et al 2010)

.Drainage of feaces into the water bodies is known and the first rains after a dry spell are called names indicative of washing away feaces into the water holding bodies (Ogwa-cet -Langi, koth marapena orwok ceth-Japadhola (personal communications from Drs. Agwai& Okuni J).

This is a very dangerous route of infection where man can easily get Taenia egg infections to cause human cysticercosis

CONTROL OF PORCINE CYSTICERCOSIS IN UGANDA

1. Lingual inspection; this is the control carried out in livestock markets eg Ochero, awelo and Karachi (Amolator and Kaberamaido)

Success; it helps in identifying infected pigs that a removed from the normal trade chain. It also alerts the Veterinary and public health personnel about the disease.

Failure; i) it is just a simple whistle blower on very shallow approach since

very many cysticercotic pigs may be lingual negative. ii) The rejected pigs are left with the farmers who have no

enforceable obligation to destroy the pigs hence clandestine slaughter/sale to unsuspecting community members is the immediate option to the rural poor farmers.

Clandestine slaughters have been observed to help in transmission of the disease (Praet et al 2010, Zoli et al 2003 Cysticercosis working group Peru, 1993)

2. Pork inspection;Success; is a regular activity at only one place in Uganda (Wambizi )pig slaughter house. Less than 0.1 % of the slaughters are diagnosed have cysticercosis at meat inspection per year

Failure; the inspection being carried out is very superficial and can not detect lightly infected pigs

The control measures being used in uganda help only to stop the transmission from a very small proportion of infection. There is need to try to prevent transmission from all the known avenues

CONTROL MEASURES USED ELSEWHERE OUTSIDE UGANDA

1. Community led total sanitation (CLTS). (Kamal Kar, Institute of development studies University of Sussex Brighton

UK.) The communities are made to under go attitude and behavioral change

towards sanitation . Awareness is carried out and the members of the community designs the way

to stop the human fecal disposal It is assumed to stimulate the construction and use of latrines in a cascade

mode. The community tends to police the activities. It is being promoted by international NGO eg Plan international , UNCEF,

WaterAid etc (www.community ledsanitation.org)It has bee tried;Kenema district , Sierra leone. has attained ODF statusTubmanburg, Liberia started and target is ODF by June 2013

2. Public health and pig management” education interventions.

Is where there is aggressive education campain in many of the communities; markets, schools, workshops etc. Educational materials eg videos, leaflets, posters, booklets and training manuals are given to communities. The training materials are made more of pictorial than

text so that they can lend easily to even the illiterate members of the communities.

The leaflets and booklets are distributed to the household for daily references.

The communites are advised to follow/adhere to the eight cysticercosis fighter principles; (a)build pig pens and never allow pigs out of the pig pen. (b)Dig and use an enclosed latrine with a closing door for all human defecations. (c)Immediately dispose children’s’ feaces in pit larine.(d)Thoroughly wash hands after latrine and before eating anything. (e)Boil water for domestic use. (f)Never eat or sell infected pork. (g)Consult a livestock extension officer whenever signs of cysticercosis are seen in pork.(h)Consult medical services if signs of worms or epilepsy happen in any member of the household. Note: incentives (pig feeds, compensation for the cysticercotic pig) are needed if the rural poor farmers are to comply with the protocols used in this approach) (Ngowi et al 2008)

3.Chemotherapy to pigs

Oxfenbendazole and albendazole have ability to kill the cysts of Taenia solium with in the body of the infected pigs. This can deter infecting the human.It can be used to treat (pre-slaughter) infected pigs before they can be slaughtered for human consumption.(Pondja et al 2012).

4. Combined mass human and porcine chemotherapy.

Mass chemotherapy (praziquantel) for intestinal Taenia worms in the humans Mass chemotherapy for porcine cystocercosis (oxfenbendazole) is a possible control strategy. The mass treatment in the humans is assumed to clear the humans of the Taenia solium worms which reduces the environmental contaminations hence less infective materials for the pigs. The mass treatment in the pigs is assumed to clear pigs of the larvae of Taenia solium which reduces infective materials for the human beings. It also has an economic value in that the porcine meat is cleared of the cysts hence less condemnations of pork (Garcia et al, 2006)

There is a possibility of mass contamination of the environment due to the mass expulsion of Taenia from the humans at the same time, if open-air defecation is carried out

Inflammatory reactions occur to the cysts in the muscles which can make the meat unsightly and unsuitable for human consumption for approximately 6 months (Sikassunge et al 2008).

Treated pigs remain susceptible and re-infections can occur and the re-infected pigs can transmit the parasite with in short time.

Coordinating the giving the drugs and slaughter before re-infection can be very problematic and can fail the exercise (Assana et al 2010).

Disadvantages;

5. Vaccination of pigsVaccination was identified as valuable approach for the control of cysticercosis by preventing transmission of Taenia solium (Lightowlers 1999).

TSOL18 vaccine has been proven effective in trials in Mexico, Peru, Cameroon and Honduras with 99.3-100% protection against experimental challenge infections (Flisser et al 2004, Gonzalez et al 2005 Lightowlers 2006). Successful Field trial has been carried in cameroon Assana et al 2010)

Good and effective control program will involve a multi-disciplinary and multilevel approach due to the complex epidemiology of Taenia solium. This will demand full cooperation of medical, public health workers, veterinarians and the communities . All need to be working in synergistic approach for proper control/reduction in the occurrence of Taenia solium cysticercosis. Laxity of any of the actors will fail any control program. (Murell and Pawlowski 2005)

General conclusion about control of porcine cysticercosis

AFRICAN SWINE FEVER

African swine fever (ASF) is caused by the African swine fever virus of the asfivirus.

ASF TRANSMISSION CYCLES

ASF Infected pig infects in-contact pig

Domestic cyclepig

pig pig

Soft tick

ASF virus Infected soft infects in-contact pig in pens

Intermediate cycle

ASF virus circulates among soft ticks and in-contact wild pigs

Interface grounds for wild and domestic pigs

sylvatic cycle

Soft tick Wild pig

BURDEN OF ASF

Date District

•3/02/2006 Adjumani•10/05/2006 Moyo•31/06/2006 Wakiso•24/10/2006 Kiboga•31/10/2008 Manafa•12/12/2008 Kapchorwa•20/04/2009 Nebbi•26/04/2010 Kasese•15/06/2010 Moyo•30/08/2010 Gulu•21/10/2010 Gulu•08/04/2011 Masindi•09/05/2011 Nebbi•4/05/2011 Kyankwanzi•15/06/2011 Nakasongola•16/09/2011 Lwengo•    

Date District 17/11/2011 Adjumani 28/11/2011 Wakiso 14/12/2011 Kabaale 20/08/2012 Buikwe 17/09/2012 kyankwanzi 24/09/2012 Z o mbo 20/11/2012 Kabala 05/06/2012 Kabarole 10/05/2012 Moyo 13/11/2012 Kyenjojo 21/01/2013 Kiboga 04/02/2013 Nebbi

Impact of ASF

It is endemic in UgandaMany mortalities in any out break (70-100%A lot of resources wasted in regular surveillanceThe depopulate strategy costs framers the investmentDiscourages breeding strategy

Control of ASF in Uganda

Halt to the movement pigs and products to and from areas of out break.Rapid slaughters of all the contact pigs to the affected flocks

Proposed control of ASF Improve production systems ; housing, hygiene, avoid uncooked swillImpose well legislated/ enforceable quarantines

Control of pig trade; health ASF pathogen free pigs are allowed for trade.

Prevent possible interaction domestic pigs with wild suids. Eradication of ticks in sties before introducing new pigs.Proper basic bio-security (footbaths, restricted visitation to the farm) Sale of bush meat (wild siud) be done in approved safe ASF proof ways.

Continued surveillance, eradication of infected by total slaughter of the sick and those in contact pigs. This needs some organ eg the state to put in place compaciatory effort for the farmers to have full compliance and cooperation.

Total confinement total closed system where influence of pigs/other animals is minimized should be encouraged

Pig holding area

Bare ground for daily sweeping

Most peripheral perimeterMiddle perimeter

Surface for tick control

Entry/exist

Disinfectant Foot bath

Proposed enclosure for ASF control

Foot and mouth disease in pigs in Uganda

This is not considered as a threat to the pig industry. The role of pigs in the cycles of FMD observed in the country is not known(Drs. Kyokwojuka and Asimwe A. MAAIF)

Intestinal worms in pigs in Uganda

Nematode exist in pigs in Uganda (Nissen et al 2011, Waiswa et al 2007.

Impact;Some are zoonotic A. suum, T.suisControl ; de-worming with antihelmentics

Advice; indigenous Traditional knowledge on worm control be explored (Prof. Ejobi)

Ecto-parasites in pigs in Uganda

Mange lice, fleas, and jiggers are common in pigs in Uganda

Impact; poor growth

Control; acaricides and ivermectin is used