Comparison of Epidemiological Methods for Estimation of Hepatitis B Incidence and Residual Risk for Blood Donors in Southern Brazil

Table 4

HBV incidence and residual risk for stand-alone HBsAg and anti-HBc seroconverting repeat blood donors in southern Brazil, 2004–2006.

Parameter	Value
Number of HBsAg or anti-HBc seroconverting donors^1	11
Time at risk (person-years) for HBsAg or anti-HBc seroconverting donors	24.93
Time at risk (person-years) for all repeat donors	54788.73
Incidence per 100.000 per year (95% CI)^2	20.09; (10.03, 35.94)
Residual risk (95% CI)^3	1 : 3082; (1 : 17229, 1 : 61734)

¹One HBsAg positive and anti-HBc negative, and ten HBsAg negative and anti-HBc positive donors.
²Confidence interval.
³Assuming Poisson distribution for 11 seroconverting cases.