A team of researchers from National Taiwan University and the Centers for Disease Control (CDC) yesterday said they have developed an eight-level prediction score to identify children who have an increased risk of contracting tuberculosis (TB).
Taiwan has a moderate tuberculosis burden, with an annual incidence of about 70 per 100,000 people from 1997 to 2005, according to the team.
To lower incidence rates of the disease, the CDC has been working on contact investigation and preventive treatment for people who have latent infections.
Young children who have had contact with infected people are especially susceptible to developing active tuberculosis, according to the centers.
The chances that they would contract the disease are about 240 times higher than for children of the same age who had not come into contact with an infected person, the centers said.
The study — which developed an grading system to categorize the risk children aged from zero to 12 face of developing active tuberculosis within three years — can help identify and prioritize preventive treatment for children who are at a high risk of developing active tuberculosis, it added.
Chan Pei-chun (詹珮君), a CDC physician and the study’s leading author, said the research team collected data from 9,411 children aged zero to 12 years old in 2008 and 2009.
It collected measurements including reactions to tuberculin skin tests, smear-positivity, residence in high-incidence areas and gender, Chan said.
The study found that the risk of developing active tuberculosis within three years was 100, 7.8, 4.3, 1.0, 0.7 and 0.2 percent for children with risk scores of seven, six, five, four, three, and two respectively.
The centers said it estimated that for every 30 children with a risk score of five who are treated with isoniazid preventive therapy (IPT), one infection could be prevented.
“A child [who has come into] contact [with the disease and has been] diagnosed with latent TB infection receiving IPT has a 95 percent of chance of averting the subsequent development of active TB disease,” Chan said.
“Children who are at risk of developing the disease should be treated with the preventive therapy,” he added.
The study was published in the American Journal of Respiratory and Critical Care Medicine and the canters said it would be taken into account for the development of tuberculosis control measures.