Updated on 21 August 2013
The new TB screening strategy looks fortelltale antibodies in the blood that are found only when a person is fighting off active TB.
Singapore: More than 20,000 people in Pakistan are being tested for the potentially deadly stage of tuberculosis using a new strategy developed at UC Davis Health System, US, to effectively detect the disease in children for the first time.
At least 600 million people in Pakistan, India and Bangladesh are infected with the tuberculosis bacterium Mycobacterium tuberculosis. Each year, at least three million people reach the potentially deadly stage called active TB. The condition is treatable with antibiotics, but conventional tests inevitably miss more than one out of three active cases. About 400,000 die from the disease in South Asia every year.
The new TB screening strategy looks fortelltale antibodies in the blood that are found only when a person is fighting off active TB. In conventional screening, a laboratory worker must identify the bacterium in a sputum sample observed under a microscope. This century-old test rarely picks up more than 50 percent of active cases of lung TB. The new antibody test is expected to detect about 80 percent of active cases.
The new test requires a few drops of a blood sample and takes two hours to provide results, while the sputum microscopy test requires three sputum samples collected over three days. The speed of the antibody screening means that many millions more people could be screened worldwide per year, according to researchers.
The new strategy is based on an FDA-approved diagnostic instrument. Its application to detect TB antibodies was developed by UC Davis Medical Center scientists in collaboration with colleagues in Pakistan. Preliminary trials funded by the US Agency for International Development (USAID) were reported in the journal Clinical and Vaccine Immunology. The new, large-scale research trial is funded by USAID and the World Health Organization (WHO). Another grant awarded in July 2013 sponsored by the US State Department and USAID will focus on developing and commercializing the TB diagnostic test in collaboration the Forman Christian College in Pakistan.