The burden of infectious disease in New Zealand

New Zealand mortality records for the years 1980 to 1993 were analysed to estimate the aggregate burden of infectious disease using a recoding of ICD-9 codes to identify deaths with infectious aetiology. The recoding scheme was modified from one developed by US CDC, which used expert panels to assign ICD codes to categories dependent on the proportion of the code attributable to infection. ICD-9 Chapter One ('Infectious and parasitic diseases') accounted for only 0.7% of total deaths. Following recoding, this proportion increased tenfold, with 6.9% of deaths attributable to infectious disease. This proportion was stable or declined only slowly between 1980 and 1993. While rates varied by age, gender and ethnicity, the results indicate that infectious disease still accounts for a substantial proportion of the burden of disease in New Zealand.