‘Overview of ASF Impact and

Surveillance in Kenya’

By: Joseph M. MachariaJane W.K. GithinjiJacqueline L. Kasiiti

Central Veterinary Laboratories, Kabete

African Swine Fever (ASF) First described from Kenya in 1910

(Montgomery, 1921) Defined as a highly contagious viral disease

with high mortality Natural hosts are pigs, warthogs, bush pigs,

and giant forest hogs. The argasid tick (ornithodorous moubata

porcinus) can serve both as vectors & reservoirs

It is a notifiable disease in Kenya – suspect cases must be reported to the DVS.

Montgomery R.E. (1921) A Form of Swine Fever occurring in British East Africa (Kenya Colony) J. Comp. Pathol. 34: 159 - 191.

Reported ASF Outbreaks

T U R K A N A

M A R S A B I T

M A N D E R A

W A J I R W E S T P O K O T

S A M B U R U I S I O L O

B A R I N G O E .

M A R A K W E T T R A N S - N Z O I A M T .

E L G O N

G A R I S S A

U A S I N G I S H U

K A K A M E G A B U N G O M A

L A I K I P I A B U S I A N Y A M B E N E

N A N D I M E R U

S I A Y A N A K U R U

V I H I G A N Y A N D A R U A

N I T H I K E R I C H O K I S U M U

N Y E R I

T A N A R I V E R

M W I N G I K I R I N Y A G A

E M B U H O M A _ B A Y B O M E T

N Y A M I R A

N A R O K

K I S I I M U R A N G A M I G O R I T H I K A

K I A M B U M A C H A K O S

T R A N S - M A R A

K I T U I

K A J I A D O

K U R I A N A I R O B I

M A K U E N I L A M U

K I L I F I T A I T A

T A V E T A

K W A L E M O M B A S A

T H A R A K A

U G A N D A

E T H I O P I A

S O M A L I A

T A N Z A N I A

N

S U D A N

Laikipia1954

Kiambu1958

Trans-Nzoia1964

ASF Outbreaks - 1994

T U R K A N A

M A R S A B I T

M A N D E R A

W A J I R W E S T P O K O T

S A M B U R U I S I O L O

B A R I N G O E .

M A R A K W E T T R A N S - N Z O I A M T .

E L G O N

G A R I S S A

U A S I N G I S H U

K A K A M E G A B U N G O M A

L A I K I P I A B U S I A N Y A M B E N E

N A N D I M E R U

S I A Y A N A K U R U

V I H I G A N Y A N D A R U A

N I T H I K E R I C H O K I S U M U

N Y E R I

T A N A R I V E R

M W I N G I K I R I N Y A G A

E M B U H O M A _ B A Y B O M E T

N Y A M I R A

N A R O K

K I S I I M U R A N G A M I G O R I T H I K A

K I A M B U M A C H A K O S

T R A N S - M A R A

K I T U I

K A J I A D O

K U R I A N A I R O B I

M A K U E N I L A M U

K I L I F I T A I T A

T A V E T A

K W A L E M O M B A S A

T H A R A K A

U G A N D A

E T H I O P I A

S O M A L I A

T A N Z A N I A

N

S U D A N 30 farms

comprising a total of 1442 pigs with a mean stocking density of 48 (sd 102, min 2, max 550).

ASF confirmed in July 1994 but few farmers and some vets. noticed it as early as April.

KiambuThika

KajiadoNairobi

1994

ASF Outbreaks - 2001

T U R K A N A

M A R S A B I T

M A N D E R A

W A J I R W E S T P O K O T

S A M B U R U I S I O L O

B A R I N G O E .

M A R A K W E T T R A N S - N Z O I A M T .

E L G O N

G A R I S S A

U A S I N G I S H U

K A K A M E G A B U N G O M A

L A I K I P I A B U S I A N Y A M B E N E

N A N D I M E R U

S I A Y A N A K U R U

V I H I G A N Y A N D A R U A

N I T H I K E R I C H O K I S U M U

N Y E R I

T A N A R I V E R

M W I N G I K I R I N Y A G A

E M B U H O M A _ B A Y B O M E T

N Y A M I R A

N A R O K

K I S I I M U R A N G A M I G O R I T H I K A

K I A M B U M A C H A K O S

T R A N S - M A R A

K I T U I

K A J I A D O

K U R I A N A I R O B I

M A K U E N I L A M U

K I L I F I T A I T A

T A V E T A

K W A L E M O M B A S A

T H A R A K A

U G A N D A

E T H I O P I A

S O M A L I A

T A N Z A N I A

N

S U D A N

From August 2001, 11 farms comprising a total of 9000 pigs.

KiambuThika

Nairobi2001

ASF Outbreaks – 2006/07

T U R K A N A

M A R S A B I T

M A N D E R A

W A J I R W E S T P O K O T

S A M B U R U I S I O L O

B A R I N G O E .

M A R A K W E T T R A N S - N Z O I A M T .

E L G O N

G A R I S S A

U A S I N G I S H U

K A K A M E G A B U N G O M A

L A I K I P I A B U S I A N Y A M B E N E

N A N D I M E R U

S I A Y A N A K U R U

V I H I G A N Y A N D A R U A

N I T H I K E R I C H O K I S U M U

N Y E R I

T A N A R I V E R

M W I N G I K I R I N Y A G A

E M B U H O M A _ B A Y B O M E T

N Y A M I R A

N A R O K

K I S I I M U R A N G A M I G O R I T H I K A

K I A M B U M A C H A K O S

T R A N S - M A R A

K I T U I

K A J I A D O

K U R I A N A I R O B I

M A K U E N I L A M U

K I L I F I T A I T A

T A V E T A

K W A L E M O M B A S A

T H A R A K A

U G A N D A

E T H I O P I A

S O M A L I A

T A N Z A N I A

N

S U D A N

KiambuThika

NairobiEldoretNakuruKisumuBusia.

2006/07 From

November 2006.

ASF Outbreaks – 2010/11

T U R K A N A

M A R S A B I T

M A N D E R A

W A J I R W E S T P O K O T

S A M B U R U I S I O L O

B A R I N G O E .

M A R A K W E T T R A N S - N Z O I A M T .

E L G O N

G A R I S S A

U A S I N G I S H U

K A K A M E G A B U N G O M A

L A I K I P I A B U S I A N Y A M B E N E

N A N D I M E R U

S I A Y A N A K U R U

V I H I G A N Y A N D A R U A

N I T H I K E R I C H O K I S U M U

N Y E R I

T A N A R I V E R

M W I N G I K I R I N Y A G A

E M B U H O M A _ B A Y B O M E T

N Y A M I R A

N A R O K

K I S I I M U R A N G A M I G O R I T H I K A

K I A M B U M A C H A K O S

T R A N S - M A R A

K I T U I

K A J I A D O

K U R I A N A I R O B I

M A K U E N I L A M U

K I L I F I T A I T A

T A V E T A

K W A L E M O M B A S A

T H A R A K A

U G A N D A

E T H I O P I A

S O M A L I A

T A N Z A N I A

N

S U D A N

Kakamega2010

KiambuThika

NairobiKajiado

KakamegaKisumuBusia.2010/11

From September 2010.

ASF Outbreaks – Total Districts Confirmed

T U R K A N A

M A R S A B I T

M A N D E R A

W A J I R W E S T P O K O T

S A M B U R U I S I O L O

B A R I N G O E .

M A R A K W E T T R A N S - N Z O I A M T .

E L G O N

G A R I S S A

U A S I N G I S H U

K A K A M E G A B U N G O M A

L A I K I P I A B U S I A N Y A M B E N E

N A N D I M E R U

S I A Y A N A K U R U

V I H I G A N Y A N D A R U A

N I T H I K E R I C H O K I S U M U

N Y E R I

T A N A R I V E R

M W I N G I K I R I N Y A G A

E M B U H O M A _ B A Y B O M E T

N Y A M I R A

N A R O K

K I S I I M U R A N G A M I G O R I T H I K A

K I A M B U M A C H A K O S

T R A N S - M A R A

K I T U I

K A J I A D O

K U R I A N A I R O B I

M A K U E N I L A M U

K I L I F I T A I T A

T A V E T A

K W A L E M O M B A S A

T H A R A K A

U G A N D A

E T H I O P I A

S O M A L I A

T A N Z A N I A

N

S U D A N

Laboratory Testing prior to 2006 Testing Laboratories:

Institute for Animal Health, Pirbright, UK

Onderstepoort Veterinary Institute, Exotic Diseases Division, South Africa

Tests performed were: Virus isolation in bone marrow

macrophage cell cultures Polymerase Chain Reaction (PCR) ELISA for serum samples

From 2006: CISA-INIA, ILRI

Tests used: Detection of ASFV genomic DNA by PCR and sequencing Virus isolation in primary culture cells. indirect ELISA – OIE Manual of diagnosis (OIE, 2004) INGENASA ELISA commercial kit for comparison.

ELISA vs PCR/Virus Isolation

CVL Lab. No

Sample Source district

Serology PCR Virus Isolation

P2 Liver, heart, lung Kiambu Negative Positive Positive

P3 Spleen, LN gastric, Kidney Eldoret Negative Positive Positive

P4 Spleen Nakuru Negative Positive Positive

P49 Serum (1) Kisumu Negative Positive Positive

P7 Sera (1-5) Nakuru Negative Positive Positive P8 Sera (1-8) Eldoret Negative Positive Positive P9 Liver, Lung, Spleen, Intestine Busia Negative Positive Positive

Results from CVL Kabete & CISA-INIA, March 07

Capacity for Surveillance Limited - FAO TCP/KEN/6612 provided

some assistance in Strengthening of Laboratory Diagnosis of African Swine Fever (ASF) – ended 2000 – in collaboration with Dr. Mary Louise-Penrith of OVI.

Need for capacity at CVL Kabete to confirm ASF using PCR

Need for a surveillance program for ASF –And Contingency Plan

Kenya: Laboratory Network

T U R K A N A

M A R S A B I T

M A N D E R A

W A J I R W E S T P O K O T

S A M B U R U I S I O L O

B A R I N G O E .

M A R A K W E T T R A N S - N Z O I A M T .

E L G O N

G A R I S S A

U A S I N G I S H U

K A K A M E G A B U N G O M A

L A I K I P I A B U S I A N Y A M B E N E

N A N D I M E R U

S I A Y A N A K U R U

V I H I G A N Y A N D A R U A

N I T H I K E R I C H O K I S U M U

N Y E R I

T A N A R I V E R

M W I N G I K I R I N Y A G A

E M B U H O M A _ B A Y B O M E T

N Y A M I R A

N A R O K

K I S I I M U R A N G A M I G O R I T H I K A

K I A M B U M A C H A K O S

T R A N S - M A R A

K I T U I

K A J I A D O

K U R I A N A I R O B I

M A K U E N I L A M U

K I L I F I T A I T A

T A V E T A

K W A L E M O M B A S A

T H A R A K A

U G A N D A

E T H I O P I A

S O M A L I A

T A N Z A N I A

N

S U D A N

Clinical Signs Major Clinical Signs observed:

Cyanosis of the ears, perineum and ventrum Fever – Approx. 410C for those in the initial stages Hypothermia & difficult breathing – advanced stages Innappetance/Anorexia Lethargy Recumbency/Moribund followed by death.

Less commonly observed clinical signs: Frothy salivation Blood tinged diarrhoea Coughing and emaciation

Other Observations

All age groups are affected

The general body condition on most farms – fair to poor

Mean morbidity – 43% (sd 28%, min 5%, max 83%)

Mean mortality – 33% (sd 26%, min 2%, max 77%) – may be due to intervention measures – subclinical?

Gross Pathology Purple coloration of the skin Haemorrhages throughout most of the

internal organs Lymph nodes markedly swollen,

reddened, haemorrhagic and look like blood clots

Massive clotting in the urinary bladder; Excessive oedema in body cavities, lungs

and the pericardium Spleen markedly enlarged and congested.

Control and Eradication

Implementation procedure in accordance with the Animal Diseases Act CAP 364 and the Pig Industry Act CAP 361 of the Laws of Kenya

Affected farms placed under immediate provisional quarantine, pending laboratory confirmation.

Affected farms and administrative divisions consequently placed under full quarantines.

DVS issues press release to alert public on social economic importance of ASF and the eradication measures put in place.

Quarantine announcements by the concerned District Veterinary Officers.

Control and Eradication contd.

DVS appoints a team to coordinate surveillance, control and eradication of the disease.

Team meets pig owners, butchers & department extension staff of affected areas.

Team administers questionnaire to get ASF-related information covering broad areas like: general management and housing, movement of pigs from

within & outside Kenya, health care & time of disease onset.

DVS sends a circular detailing control measures to VOs. VOs instructed to develop inventories of pig keepers, to

determine the population of pigs, to identify all infected farms and to institute strict pig movement controls to stop spread of the disease.

Control and Eradication contd.

Instructions to pig farmers: Not to allow visitors in their piggeries. Persons/vehicles go

thru’ Magadi soda placed at entrance. Avoid feeding pigs with swill. To house all roaming pigs. Isolate and kill clinically sick and in-contact pigs and

incinerate or deep bury them under veterinary supervision. Clean well and disinfect depopulated premises. Re-stock

after six months if sentinel pigs fail to become infected. Slaughter ‘Healthy’ pigs from infected farms at premises

designated to slaughter only pigs from infected farms. Pigs from clean farms must be accompanied by a no

objection letter, a health certificate and a movement permitto the other slaughter houses.

Bury offal six feet deep & cover with Magadi soda or incinerate.

Main Features of Kenyan Outbreaks –Questionnaire

All farms fed their pigs on un-boiled hotel left-overs (swill), with a few of them supplementing with commercial feeds.

Uncontrolled and sometimes illegal movement of pigs and pig products within the country and into the country

No spreading into other districts due to strict quarantine procedures

Freely roaming pigs, bush pigs and warthogs. Wild pigs are prevalent in Thika, Ngong, Karen & around Kikuyu township.

Permits for importation of pork products obtained from Ministry of Health and Customs clearance when Legal Notice No. 28 of 2000 allows only the DVS to issue import permits for animals, animal products and by-products.

The disease is noticed long before it is confirmed.

Main Features of Kenyan Outbreaks – contd. The swine production units on these farms can be described as a loose

function of farrow-to-finish, farrow-to-wean and feeder operations; with the latter dominating. No farm practices all-in, all-out production system.

Majority of the farmers buy their replacement stock from Kiambu district. Nonetheless, most of them were unwilling to name the farms of origin.

Only 10% of the farms have double fencing for their piggeries.

Only 2 slaughter houses kept some records of source (owner, district of origin, permit number and date of issue, and number of pigs transported) and meat inspection (identity of animal with respect to owner, reasons for condemnation and date).

Apart from Ndumboini slaughter house in Kiambu district not keeping any records, they often procure pigs from as far as Busia district, probably from across the border.

The average pig keeping experience of farmers is 6 years, and none of them is licensed. The health care services offered on these farms are through private veterinarian (46%), government staff (15%), farm manager (15%) and none (24%).

Challenges of Eradication

Some farms have quite a big pig stock;

Low prices offered by the butchers;

Lack of compensation by the government;

Lack of cooperation and plain stubbornness.

Farmers unwilling to name sources of replacement stock

Lack of knowledge as to the actual population at risk

Failure to license piggeries

Inadequate communication between DVS & private sector

The Pig Industry Control Board is not operational

References Montgomery R.E. (1921) A Form of Swine Fever occurring in British

East Africa (Kenya Colony) J. Comp. Pathol. 34: 159 - 191. Kenya Department of Veterinary Services Reports OVI, South Africa Laboratory Results CISA-INIA Laboratory Results

Acknowledgements Kenya Agricultural Research Institute (KARI), International Livestock Research Institute (ILRI) CISA - INIA Spain Institute for Animal Health, Pirbright, U.K. Onderstepoort Institute for Exotic Diseases, Republic of South Africa Food an Agriculture Organisation of the United Nations (FAO)

THANKS