PCVD and PCV2 Vaccination Options
Porcine circovirus type 2 ( PCV2) is the essential causative agent of post-weaning
Multisystemic Wasting Syndrome (PMWS), a multi factorial syndrome affecting pigs
worldwide. PCV2 has also strongly been associated with pneumonia, enteritis, and
reproductive failures, commonly called Porcine Circovirus Diseases ( PCVD) ( Allan
and Ellis, 2000). Whether Porcine dermatitis and nephropathy syndrome (PDNS) is
caused by PCV2 has not yet been definitely established. The PCV2 virus is a very
stable virus and it is also resistant to the common disinfectants. Transmission
of the virus could be vertically (sow to its fetus) & horizontally (e.g. pig to
pig contact & insemination).
Time of Infection and Target Cells*
Pigs are in contact with the virus all along - from the sow’s womb up to their death
(slaughter or culling). Gametes are apparently not sensitive to PCV2 infection (
Mateusen, 2007), but as soon as thezona pellucida has been removed from the embryo,ALL
their cells appear to become susceptible to the PCV2 infection (Mateusen, 2004).
Target cells of PCV2 change depending on the age of infection. During the major
part of gestation, the most sensitive cells are hepatocytes (liver cells) and cardiomyocytes
(heart cells); this is why the liver and the heart are important organs for PCV2
histopathological diagnosis in abortion cases ( Sanchez, 2003). Just before farrowing
and up to the first weeks of the piglet’s life, the susceptibility of the liver
& heart cells start to decline as the virus favors the piglets’ IMMUNE CELLS. Piglets’
immune cells particularly the macrophages and dendritic cells become the major target
cells of PCV2 at this age and unprotected piglets may become “immune-compromised”.
Later in life, macrophages and dendritic cells seem to become less sensitive while
the virus predilection changes to the parechymal & epithelial cells ( Joisel et
Figure 1. PCV2 target cells are changing over the pig lifespan.
The basis of PCV2 vaccinations*
The vaccination program strategy against PCV2 should be based on protecting the
whole herd: safeguard the embryos, the developing fetus inside the sow and protect
the immune system of the pig in its most critical period which is during the first
weeks of life. Early exposure to PCV2 of unprotected piglets may lead to the impairment
of the immune system. On the other hand, protecting piglets early in life e.g. as
early as day 1, via the colostrum of vaccinated sows, will save the piglets immune
cells and soon these piglets with mature, undamaged immune system when re-exposed
to PCV2 ( after the decline of maternal antibodies) can now mount an active immune
response against the virus which could last up to the end of fattening period. Piglet
vaccination may be useful when the PCV2 pressure is high all along their life, i.e.
at the beginning of PCV2 vaccination in the herd or in some critical epidemiological
The Three Vaccination Options with CIRCOVAC®
- Assault Program (piglet vaccination) –For piglet protection from weaning
to slaughter. To get fast result at the start of PCV2 vaccination.
- Complete Program (Sow plus piglet vaccination) –For maximum herd security.
To improve reproductive performance of breeders, to give protection to piglets as
early as day 1 & to reduce viral load in the farm by targeting the permanent carrier/
shedders breeders. Active immunization of both breeders and piglets while the breeding
herd is being stabilized and management are corrected.
- Basic Program ( Breeder vaccination) – For the best return on investment.
To improve farm efficiency, to improve reproductive performance of breeders, to
reduce viral load in the farm & to provide protection to porkers. Active immunization
of breeders coupled with good farm management & sufficient colostrum intake of piglets.
CIRCOVAC® is a killed vaccine and the only PCV2 vaccine registered for breeders
worldwide, making CIRCOVAC® the single PCV2 vaccine registered for both sows and
piglets. The dosage of CIRCOVAC® for breeders is 2 ml per head before each farrowing
and it is proven to improve reproductive performance, reduce lost days, reduce stillbirth
and mummification & improve weaned piglets per sow per year by as much as 1.6 additional
piglets (T. P. Tang et al (2009) 4th APVS, Tsukuba, Japan). Vaccinating sows with
CIRCOVAC® also protects its piglets against PCV2 infection as early as day 1 via
the transfer of maternal antibodies and immune cells thru colostrum. CIRCOVAC® is
also registered for piglets at 0.5 ml per head. This piglet dose has passed the
criteria set by authorities here and abroad and is proven to reduce mortalities
in piglets, decrease the occurrence of runts, improve growth rate and the overall
performance of piglets.
PCV2 is able to hamper performances of all age groups in the farm. It is necessary
to protect embryos and fetuses, piglets, gilts, sows and boars. Management and vaccination
are both of pivotal importance to obtain the full control of PCV2 detrimental effects.
CIRCOVAC® is the only vaccine dedicated to whole herd protection.