Detection and Control of Mouse Parvovirus

Mouse parvovirus (MPV) remains a prevalent infection of laboratory mice. We developed 2 strategies to detect and control an active MPV infection over a 9.5-mo period. The first strategy used a test-and-cull approach in 12 rooms. After all cages corresponding to MPV-seropositive bedding sentinels were removed from the room, a naïve sentinel mouse was dedicated to every 2 to 3 rows per rack and received soiled bedding from these rows every 2 wk. All 12 rooms completed 3 consecutive negative rounds of targeted testing, which required an average of 20 wk. The second strategy used a modified quarantine approach to test unique mice that were critical for breeding. The process required removing selected cages from the seropositive rack and consolidating them to a single rack within the same room. All mice in these cages were tested by using MPV serology and fecal PCR. Cages were not moved, opened, or manipulated between sample collection and the availability of test results. The cages were relocated as a group to another room, because all mice were MPV negative. The mice were retested 3 wk after the initial testing, and all were MPV seronegative. Since the rooms were cleared 4 to 5 y ago, 7915 routine bedding sentinels and colony mice were tested from these rooms, all with negative results. These consistently negative MPV test results suggest that MPV was eliminated from these rooms, rather than driven down below the threshold of detection. These 2 strategies should be considered when confronting MPV infection.