[Tuberculosis Annual Report 2011--(2) Childhood and elderly tuberculosis]

In 2011, the number of newly notified childhood tuberculosis (TB) cases (tuberculosis patients aged 0-14 years) in Japan was 84, which corresponds to a notification rate of 0.50 per 100,000. The annual notified numbers and rates (per 100,000 population) of childhood TB cases decreased steadily until 2006, when the number became less than 100, after which the numbers have since remained stable. Among the 84 childhood TB patients who were notified in 2011, 33 (39.3%) were aged 0-4 years, 20 (23.8%) were aged 5-9 years, and 31 (36.9%) were aged 10-14 years. The proportion of TB patients aged 10-14 years was higher in 2011 than in previous years. In 2011, one TB meningitis case and two miliary TB cases were reported in children. Further, 23 symptomatic patients (27.4%) were identified at medical institutions and 45 patients (53.6%) were identified by contact investigation of household members. Together, these groups of patients accounted for nearly 80% of the cases of childhood TB that were detected, which was similar to the percentage in previous years. Since 1999, the notification rates of TB patients aged 85 years and above have been consistently higher among those aged 65 years and above in Japan. The annual rate of reduction in the notification rates of TB patients aged 65-79 years has accelerated from 12,625 in 2000 to 6,427 in 2011. The proportion of TB patients aged 65 years and above has consistently increased, reaching up to more than 60% in 2011; notably, the proportion of TB patients aged 80 years and above has increased to more than 30%. The proportion of bacteriologically positive TB cases among pulmonary TB (PTB) cases was higher in those aged 65 years and above than those aged 15-64 years. The proportion of PTB patients with only nonrespiratory symptoms increased with age, reaching 28.9% in those aged 85 years and above. The proportion of TB cases associated with a patient delay of two months or longer was much less in the patients aged 65 years and above than those aged 15-64 years (14.5% vs. 25.8%), whereas the proportion of TB cases associated with a doctor delay of one month or longer was slightly higher in the patients aged 65 years and above than those aged 15-64 years (24.2% vs. 20.0%). Of the newly notified TB patients in 2010 whose treatment outcomes are available as of writing, 28.5% died within a year after the initiation of TB treatment; of these, 16.3% died within three months. The proportion of deaths within three months after the initiation of the TB treatment among the patients aged 65 years and above showed substantial increase with age from 3.6% in 65-69 years old to 17.0% in 90 years and above.