Maternally-derived antibodies do not prevent transmission of swine influenza A virus between pigs

• DOI: 10.1186/s13567-016-0365-6
• Publication Date: 2016-08-16T22:21:21Z
• Authors: Charlie Cador; Séverine Hervé; Mathieu Andraud; Stéphane Gorin; Frédéric Paboeuf; Nicolas Barbier; Stéphane Quéguiner; Céline Deblanc; Gaëlle Simon; Nicolas Rose
• Keywords: Viral Shedding

A transmission experiment involving 5-week-old specific-pathogen-free (SPF) piglets, with (MDA+) or without maternally-derived antibodies (MDA−), was carried out to evaluate the impact of passive immunity on a swine influenza virus (swIAV). In each group (MDA+/MDA−), 2 seeders were placed 4 piglets in direct contact and 5 indirect (3 replicates per group). Serological kinetics (ELISA) individual viral shedding (RT-PCR) monitored for 28 days after infection. MDA waning estimated using nonlinear mixed-effects model survival analysis. Differential rates depending piglets' initial serological status structure (direct pen-mates airborne contact). The time 71.3 [52.8–92.1] average. rate 1.41 [0.64–2.63] day. compared pattern between groups showed that MDA+ had mainly reduced susceptibility infection MDA− piglets. resulting reproduction number (5.8 [1.4–18.9]), although 3 times lower than (14.8 [6.4–27.1]), significantly higher 1. Such an efficient extended spread swIAV at population scale presence MDAs could contribute persistence farms, given fact period when is expected be impacted by can last up 10 weeks.