Longitudinal study on transmission of MRSA CC398 within pig herds

BMC Veterinary Research

Table 7 MRSA transmission parameter and R ₀ -values

		No risk antimicrobials; pIP = 0			Risk antimicrobials; pIP = 0			No risk antimicrobials; pIP = 1			Risk antimicrobials; pIP = 1
Country	*C/S* ⁴⁾	TP ₂	R ₀	95% CI	TP ₂	R ₀	95% CI	TP ₂	R ₀	95% CI	TP ₂	R ₀	95% CI
NL	377/704	0.035	0.62	0.45 - 0.84	0.089	1.54	0.84 - 2.83	0.188	3.28	1.43 - 7.49	0.470	8.17	2.65 - 25.22
DK	188/240	0.001	0.02	0.00 - 0.07	0.002	0.03	0.00 – 0.16	6958	121076	307.31 - ∞	10117	176041	287.92 - ∞
NL + DK	565/944	0.039	0.68	0.54 - 0.85	0.076	1.32	0.84 - 2.06	0.309	5.38	2.74–10.56	0.603	10.50	4.31 - 25.59

Legend: this table shows the transmission per day resulting from bivariable analysis with use of risk antimcrobials¹⁾ and the relative proportion of IP compared to the total IP (pIP) included in the model²⁾ (TP₂) and R₀-value³⁾ with its 95% confidence interval for Dutch (NL) and Danish (DK) farms separately and all farms combined (NL + DK) for pre-weaning pigs only.
1) Risk antimicrobials (tetracyclins and β-lactams) in > 1 pig per pen.
2) Interaction between variables was not significant (P > 0.05).
3) To calculate R₀, TP₂was multiplied with 17.4 days (= length of infectious period).
4) Number of MRSA cases (C) from total number of susceptibles (S) used in analysis.

ISSN: 1746-6148