Maha to introduce Cy-Tb test for latent TB from October

Moving a step closer towards the elimination of Tuberculosis (TB), the Maharashtra government is all set to introduce the Cy-Tb test – a skin test for latent Tuberculosis – from October, officials said.

The Cy-Tb test combines the accuracy of the interferon-gamma release assays (IGRA) test with the ease of use of a tuberculin skin test (TST). The Cy-Tb test has been integrated into the National Tuberculosis Elimination Programme (NTEP). The test has the capability to identify latent TB infection prior to its development into an active disease.

Dr Sandeep Sangale, joint director (TB and Leprosy), Maharashtra, informed that 13,920 vials of Cy-Tb test have been received in the first out of a total seven lots and the remaining lots will be received in a phased manner. “From the current stock received, as many as 1.40 lakh tests will be performed in the state. However, the health staff will undergo training for the Cy-Tb test,” said Dr Sangale.

Dr Aniruddha Kadu, World Health Organisation (WHO) consultant to the Maharashtra state TB programme, said that vials of Cy-Tb test have been received by the state and have been distributed to all districts in the state. Some of the supply has also reached some primary healthcare facilities and rural health facilities. “Cy-Tb test vials have to be strictly maintained at temperatures between two and eight degrees Celsius. During the test, 0.1 ml of the dose is administered intradermal to the suspected latent TB patient. After 48 hours if the induration of more than 5mm is visible, it indicates latent TB infection in the individual,” said Dr Kadu.

For the NTEP, Maharashtra has been divided into 80 districts. For every case of TB, the government considers three to four close contacts of that patient as suspected latent TB patients. All latent TB patients are put on medication under the TB prevention therapy. However, many people oppose medication without a proper diagnosis due to concerns about drug resistance, patient anxiety, and unnecessary side effects, said officials.

Dr Nitin Bhalerao, assistant director (TB and Leprosy), Maharashtra, said that latent TB patients are given blanket treatment under the TB prevention therapy. But for the past three years, the government has introduced the IGRA test in Mumbai.

“The IGRA test has been successful in 29 districts, and latent TB patients are tested and given treatment after being found infected. It has been successful in Mumbai due to good laboratory facilities. We also introduced the IGRA test two years back in Latur, Osmanabad, Kolhapur, Pimpri-Chinchwad and Aurangabad but it failed due to poor lab facilities,” said Dr Bhalerao.

Dr Prashant Bothe, city TB officer, Pune Municipal Corporation (PMC), said that half of the patients who test positive for TB in Pune are from private facilities and their close contacts suspected to have latent TB are unwilling to take medicines. “When it comes to TB patients diagnosed with TB in public facilities, not all close contacts of these patients are ready to take medicines. More than half of the suspected latent TB patients in public facilities are reluctant and oppose taking medicines for latent TB,” Dr Bothe said.

Tuberculosis is an infectious disease caused by the bacterium, Mycobacterium Tuberculosis. It can cause infection in the lungs or other tissues. It commonly affects the lungs but can also affect other organs like the spine, brain or kidneys. People with latent TB do not have any symptoms and cannot spread TB. However if left untreated, they may develop active TB in the future and spread the disease to others.