Tuberculosis in Children who Had Contact with TB --- a Preliminary
Evaluation of a National LTBI Program in Taiwan
疾病管制局 第三組 Nov. 2009
Background
Contact tracing program in Taiwan has been strengthened through free-charge policy to all close contacts of confirmed tuberculosis (TB) cases since 2007, July.
Latent TB infection (LTBI) Treatment has been provided to children contacts aged 12 years or younger through directly observed preventive therapy (DOPT) since 2008, April.
Methods
Contact aged 12 years and younger registered and had at least one TST result during Apr. 1, 2008~ May, 30, 2009, 14 months.
The data was obtained from the National Surveillance Network of Communicable Disease (NSNCD), Centers for Disease Control, Taiwan.
All contacts were followed-up until Oct, 7, 2009.
Not analysis if the index case was excluded.
ResultsA total of 6145 closed contacts aged 12 or younger were followed up
4917 (84%) contacts had very contagious index <smear (+) or culture(+) or CXR with cavitation>
Index of 5861 contacts are pulmonary TB
0~4 year: 27% 5~9 year: 46% 10~12 year: 27%
1369(28%) TST>=10mm 3548 (72%) TST<10mm
857(62.6%) LTBI treatment
512(37%) no LTBI treatment
1845(52%) 2nd TST <461 (96%) >
1703(48%) no 2nd TST
478 (13.5%) received prophylaxis
17 prophylaxis already
1686(99%) no further manage
450 (24.4%) conversion
196 start LTBI (10 DC, 4 refused, 2 INH R)
123 already prophylaxis (13 DC, 5 were INH R, 4 AE)
131 no further manage (29%)
1395(75.6%) no conversion
21 start tx (12 then DC)
338 already prophylaxis (327 then DC)
(90% on DOPT)
Those Who Developed TB
There were 31 children reported to TCDC in
contacts as TB and 16 children were confirm
ed to be TB:
age 7M~12Y, median 8.5Y,
6 bacteriology proved, 14 PTB, 2EPTB (one me
diastinal only, one neck + mediastinal)
6
The Distribution of Those with TB Diagnosis
1369(28%) TST>=10mm 3548 (72%) TST<10mm
857(62.6%) LTBI treatment
512(37%) no LTBI treatment
1845(52%) 2nd TST <461 (96%) >
1703(48%) no 2nd TST
478 (13.5%) received prophylaxis
17 prophylaxis already
1686(99%) no further manage
450 (24.4%) conversion
196 start LTBI (10 DC, 4 refused, 2 INH R)
123 already prophylaxis (13 DC, 5 were INH R, 4 AE)
131 no further manage (29%)
1395(75.6%) no conversion
21 start tx (12 then DC)
338 already prophylaxis (327 then DC)
(90% on DOPT)
3
2 (1*)
8 (4 susp. During contact tracing, 1*)
2
1 (1*)
If They Received LTBI Treatment Early
The incidence rate of 1379~1562 per 10000
0 person in those TST (+) but who did not re
ceived LTBI.
Overall, six~seven episodes of tuberculosis
(38~44%) might be preventable through prop
hylaxis/LTBI treatment program.
Conclusions
LTBI treatment is recommended for all contact children of contagious pulmonary TB.
Diagnosis and treatment of LTBI has been improving through this national LTBI program.
This preliminary analysis demonstrated that up to 44% of TB cases in children contacts could be prevented if treatment was provided in time.