header shadow

Epidemiology

Prevalence of Anti-PCV2-Antibodies

The mean PCV2-antibody half-life in weanling pigs is estimated to be 19.0 days and the window for PCV2-passive antibody decay within a population is relatively wide (Opriessnig et al., 2004). Serological studies have demonstrated that passively-acquired PCV2 antibodies decay during lactation and early postweaning periods to negative or near negative levels at the end of the nursery period (7 weeks of age) followed by active seroconversion of the majority of the population starting around 12 weeks of age (Roríguez-Arrioja et al., 2002). Allan et al. (1994) showed a similar trend for PCV1 passive antibody decay. Larochelle et al. (2003) did a comparative serologic and virologic study in 5 PMWS-affected herds and 2 herds without PMWS in Quebec. Sixty blood samples were collected in each herd in 4-week-intervals from 3-to 23-week-old pigs and it was found that all herds had similar PCV2 profiles: low PCV2-antibody levels were present at 3 weeks of age and reached very low-to-negative levels by 11 weeks of age. PCV2-infection as determined by PCR took place from 11 to 15 weeks of age at which time PCV2 seroconversion occurred. All pigs were seropositive at 23 week of age.

PCV2-passively-acquired antibodies present at 1-2 weeks of age were found to decay below ELISA cutoff level by approximately 4.9 ± 1.2 weeks of age in piglets with low levels of antibodies at weaning, by approximately 8.1 ± 1.9 weeks of age in piglets with moderate levels of antibodies at weaning, and by approximately 11.1 ± 2.5 weeks of age in piglets with high levels of antibodies at weaning (Opriessnig et al., 2004).

Serological surveys found that PCV-antibodies are present globally in almost all swine herds tested and in up to 100% of individual pigs within herds. There is a high prevalence of PCV infection in the global swine populations of Canada, France, Germany, New Zealand, Northern Ireland, United Kingdom, and the United States (Allan et al., 1994; Dulac and Afshar,1989; Edwards and Sands, 1994; Hines and Lukert, 1995; Horner, 1991; Magar et al., 2000; Tischer et al., 1982, 1986, 1995a; 1995b; Walker et al., 2000). Magar et al. (2000) found that PCV2 appeared to be the main PCV2 type circulating in Canadian pig herds and that serological evaluation using PCV1 underestimated the seroprevalence of PCV2. Most U.S. breeding herds and the majority of the sows within those herds were found to be seropositive for PCV2 (Opriessnig et al., 2004). Sibila et al. (2004) determined the presence of PCV2-antibodies by ELISA in 5 farms without a history of PMWS and in 4 farms with PMWS. Serum antibodies were detected in a higher percentage of pigs from PMWS farms but overall a high prevalence of PCV2 infection was found (Sibila et al., 2004)

References:

Allan GM, Phenix KV, Todd D, McNulty MS: Some biological and physico-chemical properties of porcine circovirus. Zentralbl Veterinarmed B. 41:17-26, 1994

Dulac GC, Afshar A: Porcine circovirus antigens in PK-15 cell line (ATCC CCL-33) and evidence of antibodies to circovirus in Canadian pigs. Can J Vet Res. 53:431-433, 1989

Edwards S, Sands JJ: Evidence of circovirus infection in British pigs. Vet Rec. 134:680-681, 1994

Hines RK, Lukert PD: Porcine circovirus: a serological survey of swine in the United States. Swine Health Prod. 3:71-73, 1995

Horner G: Pig circovirus antibodies present in New Zealand pigs. Surveil Wellington 18:23, 1991

Larochelle R, Magar R, D'Allaire S: Comparative serologic and virologic study of commercial swine herds with and without postweaning multisystemic wasting syndrome. Can J Vet Res. 67:114-120, 2003

Magar R, Müller P, Larochelle R: Retrospective serological survey of antibodies to porcine circovirus type 1 and 2. Can J Vet Res. 64:184-186, 2000

Opriessnig T, Yu S, Thacker EL, Halbur PG: Derivation of porcine circovirus type 2-negative pigs from positive breeding herds. J Swine Health Prod. 12:186-191, 2004

Rodríguez-Arrioja GM, Segalés J, Calsamiglia M, Resendes AR, Balasch M, Plana-Durán J, Casal J, Domingo M: Dynamics of porcine circovirus type 2 infection in a herd of pigs with postweaning multisystemic wasting syndrome. Am J Vet Res. 63:354-357, 2002

Sibila M, Calsamiglia M, Segalés J, Blanchard P, Badiella L, Le Dimna M, Jestin A, Domingo M: Use of a polymerase chain reaction assay and an ELISA to monitor porcine circovirus type 2 infection in pigs from farms with and without postweaning multisystemic wasting syndrome. Am J Vet Res. 65:88-92, 2004

Tischer I, Bode L, Apodaca J, Timm H, Peters D, Rasch R, Pociuli S, Gerike E:Presence of antibodies reacting with porcine circovirus in sera of humans, mice, and cattle. Arch Virol. 140:1427-1439, 1995a

Tischer I, Bode L, Peters D, Pociuli S, Germann B: Distribution of antibodies to porcine circovirus in swine populations of different breeding farms. Arch Virol. 140:737-743, 1995b

Tischer I, Glederblom H, Vettermann W, Koch MA: A very small porcine virus with circular single stranded DNA. Nature. 295:64-66, 1982

Tischer I, Mields W, Wolff D, Vagt M, Griem W: Studies on epidemiology and pathogenicity of porcine circovirus. Arch Virol. 91:271-276, 1986

Walker IW, Konoby CA, Jewhurst VA, McNair I, McNeilly F, Meehan BM, Cottrell TS, Ellis JA, Allan GM: Development and application of a competitive enzyme-linked immunosorbent assay for the detection of serum antibodies to porcine circovirus type 2. J Vet Diagn Invest. 12:400-405, 2000

PCV2

Persistence

Transmission

Derivation of PCV2-free pigs

Examples of typical Herd Profiles

General Info

Research

Control

Diagnosis

Factors

PCVAD

Molecular Organization

Pathogenesis

Host Range

Epidemiology

Related Links