Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT04938596 |
| Other study ID # |
1211225 |
| Secondary ID |
|
| Status |
Completed |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
October 4, 2021 |
| Est. completion date |
March 30, 2024 |
Study information
| Verified date |
May 2024 |
| Source |
Pontificia Universidad Catolica de Chile |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
Tuberculosis (TB) is currently one of the top 10 causes of death worldwide and the leading
cause of death from a single infectious agent (ranking above HIV/AIDS). The investigators
hypothesize that reducing respiratory exposure within the household, during the first weeks
of TB treatment initiation of the index case, can reduce new TB infections in close contacts.
For this purpose, a pilot, controlled, pre-post study will be set up, to evaluate the
feasibility of implementing a bundle of respiratory precautions to all household contacts of
new pulmonary TB cases, compared to standard of care, in primary health care in a high TB
incidence area in Santiago, Chile.
Description:
Tuberculosis (TB) is currently one of the top 10 causes of death worldwide and the leading
cause of death from a single infectious agent (ranking above HIV/AIDS). In 2018, an estimated
10 million people fell ill with TB worldwide, and more than 1.4 million people died from it,
making eradication of this disease in the next decades highly unlikely unless new
interventions are discovered. Mycobacterium tuberculosis (Mtb) transmission mainly occurs
when patients affected by laryngeal or pulmonary TB cough upon others and the mycobacteria
are spread in airborne droplets nuclei smaller than 5 μm that are subsequently inhaled by
close contacts. Although chemoprophylaxis once a new TB infection is detected is an effective
strategy to reduce the risk of contacts developing active TB, it does not prevent Mtb
acquisition; it only reduces the risk of developing active TB once infected. Currently, the
large majority of international guidelines recommend strict measures to reduce airborne
transmission in hospitalized patients with pulmonary TB, with a minimum of 2 weeks of
effective TB therapy to consider a patient no longer infectious and discontinue respiratory
isolation in healthcare settings. On the contrary, in the community, no special
recommendations regarding protection of household contacts are specified, assuming that most
of them are already infected and that the TB index case will stop infecting very quickly
under antimicrobial treatment. However, several studies show that median time to sputum Mtb
culture conversion under effective treatment takes 5-7 weeks, raising the potential for
continued transmission even despite effective treatment. Furthermore, a previous study has
shown that in Santiago, Chile, 55% of household contacts of TB cases have no evidence of TB
infection at the time of diagnosis of the index case - as categorized by negative latent TB
testing - yet under close follow-up, up to 21% of these show new evidence of having acquired
the infection based on latent TB test conversion after 12 weeks of follow-up. The
investigators hypothesize that reducing respiratory exposure within the household, during the
first weeks of TB treatment initiation of the index case, can reduce new TB infections in
close contacts. For this purpose, a pilot, controlled, pre-post study will be done to
evaluate the feasibility of implementing a bundle of respiratory precautions to all household
contacts of new pulmonary TB cases, compared to standard of care, in primary care in a high
TB incidence area in Santiago. The respiratory bundle in the intervention arm will be
implemented as soon as a new pulmonary TB case is diagnosed, will last 2 weeks and, will
include: (a) provision of N95 masks and strong recommendation of use to all household
contacts and the index case when sharing a room together, (b) recommendation to index case to
sleep in a room alone, with the door closed and avoid sharing room with others, (c) promotion
of strategies to improve house ventilation; and (d) education about TB transmission. The
investigators expect to show that this trial is feasible to proceed with a larger, definitive
cluster randomized controlled trial that will evaluate the intervention effectiveness in
reducing the incidence of new TB infections in household contacts. The results of this study
will help to answer a critical research gap in TB infection control and prevention and, it
will provide a key contribution to future policies regarding TB control and elimination
worldwide. Furthermore, in the new global context of rising infectious agents of pandemic
risk, this work may have an additional potential relevance with respect to the use,
acceptability and transmission prevention potential of a respiratory bundle in the household
setting regarding other respiratory pathogens such as SARS-Cov-2.
