You are viewing the site in preview mode

Skip to main content

Advertisement

Table 2 Secondary attack ratios of qRT-PCR confirmed influenza infection and clinical influenza, intention-to-treat analysis

From: The role of facemasks and hand hygiene in the prevention of influenza transmission in households: results from a cluster randomised trial; Berlin, Germany, 2009-2011

Confirmation of influenza infection   Control Group Mask Group Mask & Hygiene Group p-value§
   n/n SAR (95% CI#) n/n SAR (95% CI#) n/n SAR (95% CI#)  
RT-PCR* All cases 19/82 23 (13-35) 6/69 9 (3-19) 10/67 15 (5-27) 0.18
  Influenza A (H1N1) pdm09 13/56 23 (11-37) 6/58 10 (3-20) 4/50 8 (2-17) 0.16
  Influenza B 6/26 23 (5-48) 0/11 0 6/17 35 (7-60) 0.22
  Season 2009/2010 8/36 22 (10-35) 3/31 10 (0-26) 3/39 8 (0-18) 0.29
  Season 2010/2011 11/46 24 (9-42) 3/38 8 (0-19) 7/28 25 (4-45) 0.27
  Implementation of intervention < 36 h after symptom onset of index patient 5/22 23 (6-39) 1/14 7 (0-23) 1/24 4 (0-16) 0.17
Clinical (ILI**) All cases 14/82 17 (7-29) 6/69 9 (3-17) 6/67 9 (3-16) 0.37
  Influenza A (H1N1) pdm09 10/56 18 (7-31) 6/58 10 (3-20) 3/50 6 (0-13) 0.29
  Influenza B 4/26 15 (0-39) 0/11 0 3/17 18 (0-37) 0.56
  Season 2009/2010 6/36 17 (6-31) 4/31 13 (3-30) 3/39 8 (0-16) 0.57
  Season 2010/2011 8/46 17 (2-35) 2/38 5 (0-14) 3/28 11 (0-25) 0.48
  Implementation of intervention < 36 h after symptom onset of index patient 4/22 18 (4-38) 2/14 14 (0-36) 1/24 4 (0-13) 0.41
  1. *RT-PCR Real time polymerase chain reaction. **ILI Influenza-like-illness. §p-values adjusted for cluster design of the study
  2. # 95% CI 95% confidence interval. Confidence intervals were calculated using bootstrapping methods