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Bovine Viral Diarrhoea
(BVD)
BVD is the most prevalent
infectious disease in cattle and
causes a significant negative
economic impact. The
mechanism of disease is
complex, with different clinical
manifestations for transient and
persistent infections. Diagnostic
tools, using specific antibody
and virus detection techniques,
are available to assess the BVD
1,2
status of herds.
BVD Virus
1
Spikes
Taxonomy:
Flaviviridae pestivirus
Genotypes:
BVD type 1 and BVD type 2
Biotypes:
Cover
Protein Shell
Cytopathogenic (cp)
and non-cytopathogenic (ncp)
Genome
Mechanism of disease
1,2
ncp/cp biotypes
Transient infection
Reproductive dysfunction
Respiratory complications
Diarrhoea
ncp biotype
n
o
i
t
a
Birth
m
e
s
in
In
day 30–110
Early
Immunotolerance
embryonic
death
Abortion,
malformation
Rare mutation within
same viral strain
PI
cp
ncp
Persistently
infected
animal
Mucosal disease
Fatal haemorrhagic disease
2
Prevalence
Herd level seroprevalence in the EU
3
60-80
%
Prevalence of BVD type 1 and 2
3,4
1
1
50%
>90%
N
EAN U
RT
NI
O
OP
NO
EU
R
<10%
A
EU
H AME
C
I
R
50%
2
2
BVD farm status: means of diagnosis
3
1
Identifies
herds with
recent
infection
Bu
milk
m
nt
A
l
k
il k
ib o
dy d
i
t
c
e
t
e
n
o
2
Identifies
herds with
active
infection
Bu
l
k
milk
m
Vi
il k
rus
t
c
e
d et
n
io
3
In divid u
Identifies
transiently
infected/PI
animals
al
b
lo
od
Vi
sa m ple
rus
t
c
e
d et
n
io
4
st
ock
nt
A
n
ou
P o ole d y
g
Detects
recent
reinfection
of cleared
herds or
missed PI
blood
ib o
dy d
i
t
c
e
t
e
n
o
Economic impact of BVD
3,5
BVD infection can have a negative
economic impact through:
milk
Poor
reproductive
performance
Early culling and
increased mortality
among young stock
Reduced
milk production
Growth
retardation
Increased
susceptibility
to other diseases
References
 Peterhans E, Bachofen C, Stalder H, et al. Cytopathic bovine viral diarrhea viruses (BVDV): emerging pestiviruses
doomed to extinction. Vet Res. 2010;41(6):44.  Lanyon SR, Hill FI, Reichel MP,et al. Bovine viral diarrhoea: Pathogenesis
and diagnosis. Vet J. 2014;199(2):201-9.  EU Thematic network on control of bovine viral diarrhoea virus (BVDV).
BVDV Control QLRT – 2001-01573 Position paper.  Lindberg A, Brownlie J, Gunn GJ, et al. The control of bovine viral
diarrhoea virus in Europe: today and in the future. Rev Sci Tech. 2006;25(3):961-79.  Saatkamp HW, Beek PMJC,
Moen AR, et al. Financial-economic analysis of Bovine Viral Diarrhoea Virus control in Dutch dairy herds. Proceedings of
the 12th International Symposium on Veterinary Epidemiology and Economics, Durban, South Africa, 2009.
Current management
options
Ongoing BVD control
schemes aim to:
1. remove PI animals
from infected herds;
2. prevent the introduction
of BVD virus in free herds
(using live or inactivated vaccines);
3. monitor BVD status over time.
Eradication programmes in the EU
have been applied variously at
national, regional and herd level.
Management strategies in the EU
1
Essentials for a successful BVD management strategy:
1
Removal of PI animals before vaccination
2
Vaccination of cattle must induce broad and long-lasting
immunity
3
Vaccination of female cattle must confer foetal protection and
must be safe during pregnancy
4
Promotion of safe trade
5
Surveillance
Current vaccination options in the EU
i
a
t
i
ld
n
I
ng en
i
r
u
S
E
Y
S
E
Y
Use
d
i
a
t
i
l
n
d
I
S
E
Y
ect
rot io
Inactivated
vaccines
Use
d
n
on
NO
S
E
Y
te
pro cti
2
e
p
y
T
e1
p
y
p
T
on
Eradication plans in the EU
ect
rot io
NO
e1
p
y
p
T
te
pro cti
2
e
p
y
T
p
r
e
e
g
r
i
t
equired
er
Modified
live vaccine
s
e dos
l
b
u
o
n
S
E
Y
ncy
na
g
n
e
i
r
n
u
e dos
l
b
u
o
equir
e
d
er
NO
ncy
na
p
r
e
e
g
r
ti
1
1
National/regional programmes
Nordic countries
(DK, FI, NO and SE)
Austria
Netherlands
Germany
Scotland
Ireland
Northern Ireland
Brittany
Rome, Lecco and Como
Switzerland
Herd-to-herd programmes
England
France
Italy
Spain
Portugal
Reference
 EU Thematic network on control of bovine viral diarrhoea virus (BVDV). BVDV Control QLRT – 2001-01573 Position paper.
BVD type 2
BVD type 2 was first identified
in North America, where it
accounts for around 50% of
infections. Although it is
currently less prevalent in the
EU (<10% of infections), recent
outbreaks suggest that
BVD type 2 is an emerging
threat in the region.
BVD type 2: an emerging threat in the EU
North Am
Disc
Eu
ean Un
p
i
ro
n
e
t
c
e
o
R
ut
eaks
br
1
st
!
on
ica
er
y
r
e
v
o
1
References
 EU Thematic network on control of bovine viral diarrhoea virus (BVDV). BVDV Control QLRT – 2001-01573 Position paper.
Cycle of
infection
BVD control programmes have so
far failed to eradicate the disease
except for the Nordic countries.
This failure has been attributed to
poor programme management
and to the limitations of available
vaccines. The cycle of BVD
infection is perpetuated by PI
animals and naïve heifers – both
are key to the spread and
maintenance of disease in herds.
Why control programmes have failed
1
to eradicate BVD
1 Antigenic variation
2 Incorrect use of vaccines
3 Failure to remove PI animals
4 Failure to adhere to control strategies
5 Spread of BVD infections by injectables
6 Lack of marker vaccines against BVD
BVD outlook
2,3
ncp/cp biotypes
Dam
m
e
s
i
n
n
I
n
o
i
t
a
ncp biotype
day 30–110
naïve heifer
Birth
PI
References
 EU Thematic network on control of bovine viral diarrhoea virus (BVDV). BVDV Control QLRT – 2001-01573 Position
paper.  Lanyon SR, Hill FI, Reichel MP, et al. Bovine viral diarrhoea: Pathogenesis and diagnosis. Vet J. 2014;199(2):201-9.
 Peterhans E, Bachofen C, Stalder H, et al. Cytopathic bovine viral diarrhea viruses (BVDV): emerging pestiviruses
doomed to extinction. Vet Res. 2010;41(6):44.