Leprosy: new data show steady decline in new cases
9 September 2019 | Geneva | New Delhi −−Data published by the World Health Organization (WHO) show that a total of 208 619 new cases of leprosy were reported in 2018 from 127 countries, including all priority endemic countries, compared with 211 009 cases (representing a slight global decrease of 1.2%) in 2017.
The registered global prevalence of the disease at the end of 2018 decreased by 8501 cases from that reported at the end of 2017. But despite this progress, increases were observed in WHO’s Americas, Eastern Mediterranean, European and Western Pacific Regions.
The surge in the number of new cases observed in several countries is due to active case detection campaigns, particularly improved contact screening, in addition to routine leprosy control activities which has influenced trends in new case detection.
Case detection in WHO Regions
WHO’s South East Asia Region reported 71% of all global cases: 2 countries – India (120 334 cases) and Indonesia (17 017 cases) contributed 92% of the cases in this Region. In WHO’s Region of the Americas, Brazil continued to report high case levels (28 660 cases) representing 93% of all cases in this Region. Combined, Brazil, India and Indonesia accounted for 79.6% of all the new cases detected globally.
Of the 159 countries and territories that provided data, 32 reported 0 cases, 47 reported 1–10 cases, 24 reported 11–100 cases, 41 reported 101–1000 cases and 15 reported more than 1000 cases, including Brazil, India and Indonesia which each reported more than 10000 new cases.
Data from the national leprosy programmes of 23 priority countries1 accounted for 199 400 of new cases, representing 96% of total cases worldwide. This number compares favourably with cases reported in 2017; however, due to improved active case detection, more new cases were detected in Brazil, Indonesia and Somalia.
Case detection in children
Detection of leprosy cases in children is considered an indicator of recent transmission of infection in the community.
In 2018, reports on paediatric cases with grade 2 disability (G2D) were received from only 139 countries, although all national programmes were urged to document disability status for all patients, including children.
In 2018, WHO’s South East Asia Region accounted for 74% of all new paediatric cases globally, whereas the African Region reported 1723 cases, which was slightly higher than in the previous year (1684). The paediatric cases detected in global priority countries accounted for 96% of new paediatric cases, showing a similar proportion as total new cases.
The number of new cases has decreased overall from 244 796 in 2009 to 208 619 in 2018.
India, which has the highest burden of the disease, has reported a decreasing number of new cases for the past 2 years, by nearly 15 000 cases (135 485 in 2016 to 120 334 in 2017–2018).
India has also reported reductions in the numbers of new G2D cases, from 5245 to 3666, and of new paediatric cases, to less than 10 000 (9227) from more than 10 000 previously. This has been largely the outcome of the country’s national leprosy programme conducting active case detection campaigns with the involvement of female community health volunteers, resulting in high coverage over the past four years.
The way forward
Scaling up of campaigns for early case detection in several countries and initiatives to cover populations at risk with chemoprophylaxis will accelerate achievement of a world without leprosy.
WHO continues to advocate for strengthened surveillance mechanisms in countries with low prevalence to ensure that all new cases are detected.
1 Angola, Bangladesh, Brazil, Comoros, Côte d'Ivoire, Democratic Republic of the Congo, Egypt, Ethiopia, Micronesia (Federated States of), India, Indonesia, Kiribati, Madagascar, Mozambique, Myanmar, Nepal, Nigeria, Philippines, South Sudan, Sri Lanka, Somalia, Sudan and United Republic of Tanzania