Actions can be taken now to tackle delays in diagnosis and reduce transmission.
|Examining a contact in Mato Grosso state, Brazil|
The priority today for global leprosy activities is to reduce transmission. There are actions that can be implemented now that will help achieve that. However, reducing transmission to zero will need further research to develop accurate diagnostic tests, well-organized chemoprophylaxis and effective vaccines to prevent leprosy.
Leprosy surveys in many countries continue to find considerable numbers of undetected and untreated patients in the community due to delay between the onset of symptoms and detection. This delay in diagnosis increases the risks of nerve damage and disability for patients as well as contributing to ongoing transmission.
There are two specific actions that all programs should now develop that can tackle this problem of delay in diagnosis: active management of contacts and focal approaches to leprosy control. They need not be costly and they could be integrated with other Neglected Tropical Disease (NTD) programs.
One effect of this will be to increase new case detection numbers. As the Goodwill Ambassador observed in his Message (Issue #74, June 2015), this is a positive sign of improved leprosy control because of the existing hidden cases, and it will contribute to reducing transmission.
But the key to monitoring progress is not in the numbers of new cases detected but in monitoring reduction in disability (WHO Grade 2 Disability) in new cases, as proposed in the current WHO Global Strategy for 2011-2015.
Let us consider these two actions in more detail:
Contact management is an integral part of the current global leprosy strategy and is described in detail in the WHO operational guidelines.
Coverage of contact management needs to be improved, however. It should be monitored by looking at the number of contacts identified as well as the percentage of contacts examined.
Other activities can be conducted with contact management to give added value. There is the opportunity to improve community awareness through education and counseling. Contacts can be made aware of the signs of leprosy and how to seek help in the future. The index cases are important assets in the process.
Chemoprophylaxis with single-dose rifampicin can be simply added when good contact management is in place. This is also an opportunity to give positive messages to change attitudes to leprosy and those affected by leprosy by showing that the disease is not only curable, but preventable.
Maps of the distribution of leprosy over the years show a progressive shrinking of leprosy into focal pockets. This can be seen in both global and national maps of leprosy or by using Geographical Information Systems (GIS).
It no longer makes sense to have a national program that uniformly provides leprosy services to every part of the country in the same way, whether or not they have new leprosy cases.
Maps can identify discrete focal areas where there are a higher number of new cases so that more active approaches to leprosy control can be used.
These more active approaches would include focal awareness campaigns, strengthening capacity of the local health care staff, case-finding activities, and even selective surveys in communities and schools. Community volunteers, people affected by leprosy, and community and religious leaders can also be encouraged to support the local control efforts.
Maybe there could be focal immunization as was used in smallpox control or mass chemoprophylaxis as is used in other NTD programs. But that is for the future; there is still much that can be done now.
Professor W. Cairns Smith is Emeritus Professor of Public Health, University of Aberdeen, United Kingdom.