ACT 1 & 2

Active case finding of tuberculosis in Vietnam



  • The ACT1 study: 4 Districts in Hanoi Capital

  • The ACT2 trial: 70 districts in 8 provinces


PROJECTOR IMPLEMENTER: National Lung Hospital/ National TB Program

FUNDED BY: National Health and Medical Research Council (NHMRC)

CORE STAKEHOLDERS: Provincial Lung hospitals in Hanoi, Vinh Phuc, TPHMC, An Giang, Can Tho, Binh Dinh, Da Nang, Tien Giang.

PRIMARY OBJECTIVE: The ACT1&2 studies aimed to evaluate strategies to detect tuberculosis among household contacts of patients with infectious tuberculosis. The ACT1 study was a prospective cohort study that demonstrated the feasibility of serial screening using chest radiography and symptom screening. The ACT2 trial was a cluster-randomised trial that evaluated the effectiveness of screening household contacts four times in two years, compared to standard “passive” case finding.

This study was registered as a clinical trial under number: ACTRN12610000600044


The pilot study, ACT1, involved screening more than 500 household contacts with smear-positive tuberculosis in four districts in Hanoi. This study found a high rate of tuberculosis among the contacts, around three times the rate in the general community.

This formed the basis for a much larger study, called the ACT2 trial, which aimed to evaluate the effect of ‘active’ screening of household contacts upon case notification rates within the Vietnam National Tuberculosis Program.

The ACT2 trial was a cluster randomised controlled trial that enrolled 25,707 household contacts of 10,964 patients who had smear-positive pulmonary tuberculosis in 70 selected districts. The study showed that household-contact investigation and standard passive case finding was more effective than standard passive case finding alone for the detection of tuberculosis at 2 years.