Co-infection by porcine circovirus type 2 and porcine parvovirus in aborted fetuses and stillborn piglets in southern Brazil

Abstract

Porcine circovirus types 1 and 2 (PCV1, PCV2) and porcine parvovirus (PPV) are widespread in pig populations around the world. Nevertheless, only PCV2 has been associated with different clinical syndromes, thus representing a major problem to the pig industry. The association of cases of swine abortions and stillborns with PCV1 and PCV2 and PPV was studied retrospectively (2005-2007). Additional pathogens were also investigated in lesioned fetuses. The studied litters included stillborn piglets and several mummified fetuses of varied sizes. Ventricular dilatation, myocardial pale areas, and mesocolic edema were the gross lesions. Escherichia coli was detected as co-infecting with PCV2 the cases in which mesocolic edema was seen. Microscopic lesions included non-suppurative myocarditis, myocardial necrosis and fibrosis, mineralization foci and intranuclear inclusion bodies in cardiomyocytes, and interstitial mononuclear pneumonia. Samples from 7 (5.78 per cent) of 121 aborted fetuses and stillborn piglets had lesions consistent with a viral cause and showed both positive anti-PCV2 immunostaining as well as PCV2-PCR. In samples from 3 (2.47 per cent) of these 7 fetuses, co-infection with PPV was confirmed by Nested-PCR. Both viruses were detected in fetuses at different stages of gestation. Viral antigens of PCV2 were detected by immunohistochemistry mainly in macrophages and myocytes. PCV1 individually was not detected in any of these affected fetuses, but it was associated with PCV2 and/or PPV in some of them. These findings indicate that PCV2 alone or in association with PPV should be kept in mind when investigating causes of infectious abortion in pigs in Brazil.

Lawsonia intracellularis and Porcine Circovirus type-2 infection in Estonia

“…Pescador (2007) confirmed that E. coli was detected as co-infection with PCV2 in cases positive for mesocolic edema.…”

Age distribution of porcine sapovirus asymptomatic infection and molecular evidence of genogroups GIII and GIX? circulation in distinct Brazilian pig production systems

“…Studies have revealed that Brazilian pig herds are commonly infected with economically important viruses, including porcine rotavirus groups A, B and C; hepatitis E virus; Aichivirus C; porcine norovirus; porcine enteric picornaviruses; porcine parvovirus; porcine circovirus type 2 and torque teno sus virus, some of which lead to public health concerns (Pescador et al 2007;Barry et al 2008b;Zlotowski et al 2008;Cunha et al 2010;Lorenzetti et al 2011;Médici et al 2011;Gardinali et al 2012;Ritterbusch et al 2012;de Arruda Leme et al 2013Ribeiro et al 2013;Donin et al 2014;Silva et al 2014;Stipp et al 2014). It is not unusual to find pigs infected with several of these viruses at the same time (Pescador et al 2007;Zlotowski et al 2008;Médici et al 2011;Lorenzetti et al 2011;Donin et al 2014).…”

Interstitial nephritis of slaughtered pigs in the State of Mato Grosso, Brazil

“…These authors also observed that the OR increased to 22.7 (P<0.0001) when there was co-infection with both viruses. Other studies reported association between PCV2 and PPV and the development of diseases such as post weaning multisystemic wasting syndrome in pigs (PMWS), renal lesions, and reproductive failures (Allan et al 1999, Kim & Chae 2004, Fernandes et al 2006, Pescador et al 2007). …”