5% of Chennai TB patients’ kin found infected

In a recent study, scientists have found that at least 5% of relatives of TB patients in Chennai were found positive for the infection when they did a retrospective record view of the household contacts between 2007 and 2013.

In the study, recently published in the medical journal PlosOne, scientists concluded that active screening of contacts is an effective way to improve TB case detection. These contacts were screened for tuberculosis as per the recommendations in the national TB programme.

India has nearly a quarter of the world TB incidence and it is estimated that about 40% of the Indian population is infected with TB bacteria, the vast majority of whom have latent rather than active TB.

In the national programmes, screening is recommended for people living with and sharing food from the same kitchen as the infected person for at least three months before diagnosis of tuberculosis. The objective of the study was to "evaluate the yield of active case finding in household contacts of newly diagnosed smear positive TB patients and the factors associated with increased yield."

During the study, doctors screened 544 relatives of 280 TB patients and found 71 of them with an abnormal chest x-ray and more than 5% were tested positive for TB. Nearly 15% of relatives refused the test for reasons such as no symptoms, lack or time or already investigated.

While 23 people had smear and culture positive TB, three of them had smear negative and culture positive TB. In addition, three more people were tested positive for extra pulmonary TB.

"Active screening among household contacts is an effective way to improve TB case detection. The yield for new TB cases among contacts with abnormal x-ray was high in this study and use of chest x-rays in combination with symptom screen is recommended," said the study's corresponding author Dina Nair from the National Institute of Tuberculosis.

Source: Times of India