Discussion

The decreasing global trend in leprosy rates and notifications since the 1950s has also been seen in England and Wales. Despite this, as with the global figures, England and Wales leprosy incidence reductions have slowed in the last decade.2 ,6 The slight increase in case report numbers seen in 2003–2012, compared with 1993–2002, probably reflects under-reporting in the earlier decade; 82.6% (76/92) of the cases identified in the 2001–2012 audit were 2003–2012 cases (making 54.7% (76/139) of the 2003–2012 cases). Therefore, the 1993–2002 period is likely to have under-reporting as it did not have the same level of correction for missing cases.

The high proportions of cases that were male and 15–44 years old may reflect the reported increased risk of leprosy in men after puberty,17 or alternatively the demographic features of immigrants to the UK from high incidence countries. The large proportion of UK patients with leprosy that were born in South Asia reflects the high levels of migration from this region compared with other world regions, together with the high leprosy burden in these countries.6

The significant level of under-reporting in 2001–2012 highlights the current shortfalls in leprosy surveillance and reporting systems in the UK. This may have implications for case management and resource distribution in the future, particularly if the lack of complete surveillance and clear protocols for leprosy cases contributes to low clinical expertise, and misdiagnosis/underdiagnosis of cases. Although not reported to PHE by the clinician making the initial diagnosis, the cases identified during the audit had been managed by a Consultant Advisor in Leprosy. This suggests that although diagnosing clinicians appeared to be aware that patients should be treated by a specialist physician, they were unaware of the requirement to notify or the notification procedure.

Owing to the rarity of leprosy in the UK, however, and consequent low clinical awareness, it is possible that further cases were not identified. These unidentified cases may not have received the highest standard of treatment, in view of the failure to refer to a Consultant Advisor in Leprosy, and appropriate contact tracing may not have been carried out.

In addition to a probable underestimate of total case numbers due to under-reporting, there is also a lack of UK data on key WHO indicators for assessing leprosy burden reduction, such as type of disease, and the presence of grade 2 disabilities (defined as visible damage to the hands and feet, such as wounds, claw hand and loss of tissue4). Despite surveillance data from the WHO indicating continued global decreases in leprosy prevalence and incidence, comprehensive surveillance on the key indicators from all world regions is also necessary to monitor progress towards further burden reduction targets. Recent WHO reports indicate that leprosy data are not available for most of Europe, North America and numerous countries in Asia.18 This UK report and audit of cases will contribute to European figures for WHO assessment, and highlights the potential for other European countries to provide similar data. Complete case reporting in other parts of Europe will also enable a better understanding of the impact of changes in countries with the highest leprosy burden and shifting migration patterns over time on the epidemiology of leprosy in Europe.10 ,11 ,19

As the incidence of leprosy further decreases, there is a risk that the number of clinicians with expertise in its management will diminish.20 Future clinical training in leprosy management needs to be addressed in the UK and across Europe if a high standard of patient care is to be maintained.

As leprosy is rare in the UK, it is important to increase healthcare workers' awareness of the disease to ensure that patients do not experience stigma and delayed diagnosis.10 ,20 ,21 Increased clinical understanding will allow rapid diagnosis and appropriate treatment from, or in conjunction with, an experienced Consultant Advisor in Leprosy. This will help reduce the likelihood of severe neurological damage and grade 2 disabilities and ensure that timely contact tracing around infectious cases is carried out to prevent the possibility of onward transmission. Public and healthcare worker access to updated leprosy information, and clear guidance on public health action around leprosy, will enable an increased understanding of leprosy and its low infectiousness. This will help to consolidate efforts by leprosy organisations to dispel stigma around leprosy.10 ,22 ,23

PHE, in collaboration with the UK Panel of Leprosy opinion, has revised the Memorandum on Leprosy4 in order to provide the most up to date national guidance on diagnostic procedures, treatment, case management, contact tracing and notification. In addition to a recommended code of practice for case management and notification, it outlines the natural history of leprosy, and lists contact details of specialist Consultant Advisors in Leprosy and sources of further information. The Memorandum outlines steps that have been taken to strengthen and simplify national surveillance while safeguarding patient confidentiality. The Memorandum is published on the PHE website and revised as needed to keep abreast of changes in advice on clinical and public health management as well as relevant changes to the health service.

The prevalence of leprosy in high-income countries is extremely low. Nevertheless, national surveillance systems need to be robust and reliable so as to identify all cases and reduce the likelihood, however unexpected, of onward transmission. Health services in low prevalence parts of the world, such as Europe, should continue to support the maintenance of clinical and public health expertise, surveillance, and research into leprosy in order to contribute to further reducing the global burden of leprosy.