Detection of foot-and-mouth disease virus in the breath of infected cattle using a hand-held device to collect aerosols

Exhaled air of individual cattle infected experimentally with foot-and-mouth disease virus (FMDV) was sampled to assess the feasibility of a rapid, non-invasive general screening approach for identifying sources of FMDV infection. The air sampler used was a handheld prototype device employing electrostatic particle capture in a microchip chamber of 10–15μL and was shown to effectively capture a high percentage of airborne microorganisms. The particles were eluted subsequently from the chip chamber and subjected to real-time RT-PCR. Sampling exhaled air for as little as 1min allowed the detection of FMDV in cattle infected experimentally. Detection in exhaled air from individual cattle was compared to FMDV detection in serum and saliva for 3 different strains of FMDV (O1/Manisa/69, C/Oberbayern/FRG/1960 and SAT1/Zimbawe/1989). Detection of FMDV in exhaled air was possible for all strains of FMDV used for experimental infection but the period that detection was possible varied among the strains. Detection in exhaled air generally peaked on day 2–4 post infection. The perspectives of monitoring for FMDV in the breath of infected cattle are discussed in the context of real-time epidemiological contingencies.