Comparison of two size-differentiating air samplers for detecting airborne swine viruses under experimental conditions

Figures & data

Table 1. Mean RNA copies ± SD of porcine reproductive and respiratory syndrome virus (PRRSV) and influenza A virus (IAV) spiked and eluted from the filters as well as recovery efficiency (%) of the viruses as a function of virus concentration after the active technique was applied. Values are the mean of three replicates.

PRRSV			IAV
Total spiked	Total eluted	RE^* (%)	Total spiked	Total eluted	RE (%)
3.5 × 10^8	2.3 × 10^7 ± 1 × 10^6	22	1.2 × 10^7	7.8 × 10^5 ± 1 × 10^5	22
3.1 × 10^7	2.3 × 10^5 ± 1 × 10^5	1.6	1.1 × 10^6	4.6 × 10^4 ± 1 × 10^4	14
3.3 × 10^6	^†ND	^§NA	1.1 × 10^5	5.7 × 10^3 ± 8 × 10^2	12

* RE: Recovery efficiency.

^† ND: Non-detectable by qRT-PCR.

^§ NA: Not applicable.

Figure 1. Raw data of particle size distribution (concentration of log ₁₀ RNA copies/m³ of air) of influenza A virus (IAV) and porcine reproductive and respiratory syndrome virus (PRRSV) detected at different sampling periods by the Andersen cascade impactor (ACI) and the high volume Tisch cascade impactor (TCI) from mechanically generated aerosols. Lowest particle size geometric values represent the data from the back up filters. The results of the black line correspond to the ACI and the gray line to the TCI.

Figure 2. Particle size distribution (least-square means of log₁₀ RNA copies/m³ of air and standard errors) of influenza A virus (IAV) and porcine reproductive and respiratory syndrome virus (PRRSV) detected by the Andersen cascade impactor (ACI) and the high volume Tisch cascade impactor (TCI) from mechanically generated aerosols. Results represent the mean values of three replicates.

Figure 3. Particle size distribution (least-square means of log₁₀ RNA copies/m³ of air and standard errors) of fluorescein particles collected by the Andersen cascade impactor (ACI) and the high volume Tisch cascade impactor (TCI) from aerosols mechanically generated. Results represent the mean values of three replicates.

Figure 4. Volume distribution of total airborne particles (geometric mean diameter of volume of particles/m³) measured using an optical particle counter during sampling periods of 10, 20, or 30 min using the Andersen cascade impactor (ACI) (a) and the high volume Tisch cascade impactor (TCI) samplers (b). Results represent the mean values of three replicates.