January 30, the day commemorating Mahatma Gandhi’s martyrdom, is observed as Anti-Leprosy day in India to honour his selfless endeavors in caring for those impacted by the disease.
Leprosy, also known as Hansen’s disease, affects more than 120 countries, with about 2,00,000 new cases reported every year. India carries the world’s highest burden, accounting for 59.63% of cases, with 1,03,819 new cases reported in 2022-2023. These new leprosy cases affect men (61%), women (39%) and children (5.4%). Among these new cases, 2,363 cases have visible disabilities. The occurrence of new leprosy cases among children is an indicator of recent transmission and new cases with disabilities indicate delayed case detection.
Leprosy is the world’s oldest documented disease, characterised as a chronic infectious disease that predominantly affects the nervous system, mainly peripheral nerves and skin. While it is curable, if left untreated the disease may progress and lead to permanent disabilities, such as nerve damage, blindness, paralysis, and loss of sensation. The causative agent of leprosy is a bacteria named Mycobacterium leprae. Leprosy has a long incubation period, averaging three to five years or more, and symptoms can take as long as 20 years to appear.
Leprosy is not an extremely contagious disease and is not hereditary. The exact mode of transmission is not known, but some theories suggest it is transmitted via droplets from the nose and the mouth during close contact through untreated cases. Healthcare professionals may work for extended periods without acquiring the disease, indicating that leprosy does not spread through casual contact such as handshakes, hugging, sitting next to each other, or sharing a meal. Hansen’s disease is not passed on from an infected mother to her unborn baby during pregnancy, and it is also not spread through sexual contact. Debunking these myths is essential for fostering understanding and eliminating stigma.
Given the progress in the epidemiological situation of leprosy, the WHO has developed the Leprosy Elimination Framework, reflecting a paradigm shift from control to elimination, guiding countries towards the goal of “zero leprosy”. Elimination of leprosy disease is verified in a bottom-up approach; i.e., from subnational level upwards.
Given the new paradigm, reports of zero cases are essential, including at subnational level. On January 30, 2023, the Government of India introduced the National Strategic Plan and Roadmap, aiming to eliminate leprosy transmission by 2027. The union government also launched the Nikusth 2.0 web portal for reporting leprosy cases.
The leprosy data from India shows an increase in the number of new cases detected from 65,147 cases in 2020-21 to 1,03,819 cases in 2022-23. Similarly the data from Tamil Nadu showed an increase from 1,769 cases in 2020-21 to about 3,000 cases in 2022-23.
This reflects efforts by the national & TN State leprosy programme to build back from the adverse impact of the COVID-19 pandemic when case detection was less due to the diversion of field staff during the first and second waves and people were hesitant to come forward for screening, leading to a fall in reported leprosy cases.
The delayed diagnosis of leprosy leads to cases presenting with deformity and the data show an increase in deformity rates reported during the 2022-23 period. This highlights the importance of ensuring that leprosy services are fully restored, so that any backlog of cases are rapidly diagnosed to avoid deformities. Of the 1,03,819 new cases detected, 5,586 are children. The fact that child cases continue to be detected indicates active transmission
In order to raise awareness among the public, World Leprosy Day is celebrated on the last Sunday of January. The theme for World Leprosy Day 2024 was “Beat Leprosy”. This theme encapsulates the dual objectives of the day - to eradicate the stigma associated with leprosy and to promote the dignity of people affected by the disease.
National strategic plan
On January 30, 2023, the Government of India introduced the National Strategic Plan and Roadmap, aiming to eliminate leprosy transmission by 2027. The union government also launched the Nikusth 2.0 web portal for reporting leprosy cases
Footnote is a weekly column that discusses issues relating to Tamil Nadu
K Narayansamy is vice chancellor, The Tamilnadu Dr MGR Medical University, Chennai