Family Member with Tuberculosis Transfers Disease To Others In The Household- Guilt By Association!
A new study published in The Lancet shows that members of household with one member having active tuberculosis are at high risk of contracting the disease.
The study was conducted in Lima Peru, by scientists from the Harvard Medical School, Socios En Salud Sucursal Peru, Lima, Peru and Brigham and Women's Hospital, Boston.
Of the 693 households included in the study about 25% (171) had at lease one case incidence. Almost 40% of household contacts with active tuberculosis had drug-susceptibility test results, more than 90% of whom had multi-drug resistant tuberculosis. According to the authors similar prevalences have been recorded in prisons and holding centres in Siberia.
Tuberculosis strains resistant to at least both isoniazid and rifampicin, defined as multidrug-resistant (MDR), pose a major health problem. When patients are diagnosed with MDR, it is essential to actively monitor individuals who are in close contact with these patients.
The article adds: "after treatment of patients with active tuberculosis, contact investigation—investigation of people exposed to patients with infectious tuberculosis—is the top priority for tuberculosis control programmes because close contacts of patients with known tuberculosis have a higher risk of developing active tuberculosis than do people who have not had such contact."
In the study they also analyzed whether the occurrence of active tuberculosis in household contacts differed according to whether an index patient had MDR or extensively drug-resistant (XDR) tuberculosis.
This study by Becerra and colleagues is likely to have a major impact on initiatives aimed towards the global control of tuberculosis.
Source: Becerra et al. Tuberculosis burden in households of patients with multidrug-resistant and extensively drug-resistant tuberculosis: a retrospective cohort study. Lancet 9 December 2010 doi:10.1016/S0140-6736(10)61972-1