FOOT-AND-MOUTH DISEASE VACCINATION STRATEGIES IN SHEEP

AND LAMBS BY USING

COMMERCIAL OIL VACCINE

Späth, E., Robiolo, B.; León, E., Manazza, J., Duffy, S., Filippi,

J., Ham, A., La Torre, J., Smitsaart, E.

INTA-Balcarce, CEVAN-CONICET, CICVyA-INTA,

Biogénesis Bagó S.A. Argentina

Conclusions

• One dose of oil vaccine induces a duration of

immunity in adult sheep of at least one year

• A booster effect is observed shortly after

revaccination at 10, 20 or 30 days post primo

vaccination

• Lambs 30-90 days old with MDA respond to FMD

oil vaccine and produce high levels of antibodies

that persist at least for 4 months

Foot-and-mouth Disease Status South America. OIE, May 2008

Country No Free

• Ecuador

• Suriname

• Venezuela

Zone No Free

• Bolivia

• Brazil

• Colombia

• Peru

Area under intensive

surveillance

• Argentina

• Paraguay

• Brazil

• Bolivia

Country Free with vaccination

• Uruguay

Country Free without vaccination

• Chile

• French Guiana (French territory)

• Guyana

Zone Free without vaccination

• Argentina

• Brazil

• Colombia

• Peru

Zone Free with vaccination

• Argentina

• Brazil

• Colombia

• Bolivia

• Paraguay

Vaccination in sheep and lambs: background

• Emergency situation or buffer zone

• Appropriate strategies of vaccination in sheep needed

• Sheep good responder to FMD vaccination

• Results under field conditions by using conventional vaccine

needed

• Vaccination of lambs with MDA: few reports with significant

number of lambs

Materials & Methods

• Vaccine – Bioaftogen® water-in-oil single emulsion manufactured by

Biogénesis Bagó S.A. (FMD national campaigns 2004 &2005)

– Batch size: 2500 000 cattle doses (2 batches)

– BEI inactivated PEG concentrated and purified antigen: FMDV strains O1 Campos, A Arg 2000, A Arg 2001 & A24 Cruzeiro

– Sheep dose: 1 ml (Cattle dose: 2 ml)

• Trial 1: naïve sheep 1-4 years

1st dose 2nd dose N

– Group 1: T0 no 23– Group 2: T0 10 dpv 23– Group 3: T0 20 dpv 23– Group 4: T0 30 dpv 23– Non vacc: no no 10

Immuneresponse in adult sheep

0,00

0,50

1,00

1,50

2,00

2,50

3,00

3,50

4,00

4,50

0 50 100 150 200 250 300 350

days after primary vaccination

mean g

roup L

PB

E titr

es lo

g 1

0

(O1 C

am

pos)

P<0.05

0,5

1

1,5

2

2,5

3

0 50 100 150 200 250 300 350

days after primary vaccination

mean g

roup V

NT

titre

s t

o O

1 C

am

pos

(log 1

0)

Control

Group 1-1 dose

Group 2-rv 10

Group 3-rv 20

Group 4-rv 30

Liquid phase blocking

ELISA antibody titres

Neutralizing antibody titres

P<0.05

Reproductive time and vaccination/bleeding schedule in

adults and lambs

JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC JAN FEB MAR

BLEEDINGS ADULTS

BLEEDINGS LAMBS

LAMBING WEANING

2004 2005

VA

CC

INA

TIO

N

AD

UL

TS

VA

CC

INA

TIO

N

LA

MB

S

BREEDING

Trial 1 Trial 2

Experimental design: Trial 2

• Lambs born to

vaccinated ewes

Vaccination age N(days)

� G30: 30 28

� G60: 60 28

� G90: 90 30

� Non vaccinated 13

• Lambs born to non

vaccinated ewes� 4 lambs vaccinated at 30

days of age

� 2 lambs vaccinated at 90 days of ageNaïve sheep N=10

Immune response in lambs

0

0.5

1

1.5

2

2.5

3

3.5

4

0 20 40 60 80 100 120 140 160

days of age

Mate

rnally

derived a

ntibodie

s

in lam

bs b

y L

PB

E

(log 1

0)

A Arg 2001

O1 Campos

G-30 & w /o MDA vacc 30

00.5

11.5

22.5

33.5

4

30 60 90 120 150days of age

control non vacc-MDAG-30 w /o MDA vacc 30

G-60

00.5

11.5

22.5

33.5

4

30 60 90 120 150

days of age

LP

BE

antib

odie

s

log10 A

Arg

2001

control non vacc-MDA G-60

G-90 & w /o vacc 90

00.5

11.5

22.5

33.5

4

30 60 90 120 150

days of agecontrol non vacc-MDAG-90 w /o MDA vacc 90

Effect of maternally derived antibodies on primary response

• In lambs with high MDA titres (>log10 3.00),

there was a slightly impaired response at 30

dpv

• the biological impact of this suppression is

negligible as protective levels of antibodies

persisted during the whole trial.

Conclusions Recommendations

• One dose of oil vaccineinduces a duration ofimmunity in adult sheepof at least one year

• A booster effect isobserved shortly afterrevaccination at 10, 20 or 30 days post primo vaccination

• Lambs 30-90 days oldwith MDA respond toFMD oil vaccine andproduce high levels ofantibodies that persist at least for 4 months

• One or two dosesannually in adult sheep isrecommended forsystematic vaccinationprograms

• Two doses of oil vaccinein adult sheep, 10-30 days apart, isencouraged in order toenhance herd protectionin a high risk situation

• Vaccination of younglambs with high levels ofMDA is beneficial as thisinduces an effectiveimmune response

�

Thank you!