Volume 17, Number 6—June 2011
Research
Use of Antiviral Drugs to Reduce Household Transmission of Pandemic (H1N1) 2009, United Kingdom1
Table 3
Confirmed SAR of pandemic (H1N1) 2009 virus infection, according to time antiviral drug prophylaxis began after onset of illness in primary case-patient, plus timing of secondary cases after onset of primary case, United Kingdom, 2009*
Timing |
No. contacts |
No. secondary case-patients at 14 d |
SAR, % (95% CI) |
No. (%) secondary case-patients | |||
---|---|---|---|---|---|---|---|
2 d |
3–4 d |
5–7 d |
>7 d |
||||
No prophylaxis |
143 |
45 |
31.5 (24.0–39.8) |
15 |
12 |
10 |
8 |
Day 0 | 57 | 1 | 1.8 (0.0–9.4) | 0 | 0 | 1 | 0 |
Days 1–2 (<48 h) | 81 | 4 | 4.9 (1.4–12.2) | 0 | 3 | 1 | 0 |
Day 3–7 (inclusive) | 214 | 3 | 1.4 (0.3–4.0) | NA | 0 | 3 | 0 |
>7 d |
92 |
0 |
0.0 (0.0-3.9) |
NA |
NA |
NA |
0 |
Total case-patients | 587 | 53 | 9.0 (6.8–11.7) | 15 (2.6) | 15 (2.6) | 15 (2.6) | 8 (1.4) |
*SAR, secondary attack rate; CI, confidence interval; NA, not applicable.
1Elements of this work were presented at the Health Protection Agency Annual Conference in 2009. An abstract was presented at the International Conference on Emerging Infectious Diseases, Atlanta, Georgia, USA, 2010.