Surveillance of Leprosy in Kiribati, 1935–2017

Abstract

L eprosy (also called Hansen's disease) was well established in Kiribati by the early 20th century, possibly as a result of contact with Western and Chinese traders (1,2). Colonial records indicate that there were 28 known cases in 1925, when the population was ≈31,000. Kiribati, formerly the Gilbert Islands, is a country of 33 atolls, 21 of which are inhabited, spread over >1 million square miles of ocean. The country covers an area on both sides of the International Date Line and north and south of the equator. The islands became a British colony in 1916, were occupied by Japan during 1942-1943, and became an independent country in 1979. The population in the 2015 census was 110,136, with the main population located in South Tarawa (39,058 persons) and Betio (17,330 persons) (3). Betio, an islet with a deepwater port, is connected to South Tarawa by a causeway. Leprosy, caused by the bacterium Mycobacterium leprae, is a chronic disease with an indolent onset, resulting in a long period between the manifestation of the disease and the person seeking healthcare (4). Its 2 clinical forms, paucibacillary disease (PB) and multibacillary disease (MB), may have long-term consequences if untreated and can result in peripheral nerve damage, chronic ulceration, blindness, and facial disfigurement, as well as social isolation and family discord. Complications are more common in MB leprosy (5,6). Humans are the main reservoir of M. leprae. The primary mode of transmission is understood to be person to person by the respiratory route, but this route has not been proven conclusively (7). Patients with MB disease excrete M. leprae from their nasal mucosa and skin. Persons most at risk are close household contacts of those with MB, but social contacts are also at risk. Social and economic factors play a role in transmission (8). Poverty, undernutrition, crowding, and rapid uncontrolled internal migration have been associated with high rates of leprosy (9). Higher rates of leprosy were found in households of >7 persons than those with <4 persons and in homes in which >2 shared a bedroom (10,11). The First International Leprosy Conference, held in Berlin in 1897, adopted segregation as the global response to the threat of leprosy; it was commonly used by colonial governments (12). Newly diagnosed patients with leprosy were initially isolated in Kiribati before they were transported to the leprosy isolation island, Makogai, in the Fijian archipelago. Patients from Kiribati were first admitted to Makogai in 1937, although the isolation facility began accepting patients by 1911. Dapsone, the first effective drug to

Leprosy Update in China, 2019

“…11,17 Further research is required to determine whether males are at higher risk of exposure to M. leprae and development of disease than females. 18 Although China's urbanization rate reached 60% in 2019, there were still more than half of patients were peasants, indicating the rural areas will still be focus of leprosy control. 19 In 2019, there were a total of six children with leprosy in China, yielding a 14.3% decrease compared with 2018.…”

Effectiveness of population-wide screening and mass drug administration for leprosy control in Kiribati: the COMBINE protocol

“…The Republic of Kiribati is a geographically isolated nation in the Pacific region comprising 32 atolls and one raised coral island spread over a land territory of 811 km 2 amid an ocean territory of 3.5 million km 2 . The intervention site is the capital atoll of South Tarawa (population 63 439) which is the densely populated ‘transmission hot-spot’ and amplifier of leprosy disease throughout the country (see table 1 for baseline characteristics of the study population) 19. Kiribati has only one specialised leprosy clinic which is located in South Tarawa.…”

Population-wide active case finding and prevention for tuberculosis and leprosy elimination in Kiribati: the PEARL study protocol

“…Postexposure prophylaxis (PEP) of household contacts using SDR has been scaled up in recent years with the help of the Pacific Leprosy Foundation (PLF). 2 …”

“…Tuberculosis (TB, caused by Mycobacterium tuberculosis (MTB) ) is a leading infectious disease killer globally and in the Pacific, 1 while leprosy (caused by Mycobacterium leprae ) elimination remains a major challenge as well. 2 It is estimated that TB killed ~1.5 million people in 2020, despite being a preventable and curable disease. 1 At the 2018 United Nations High-Level Meeting on TB, 3 world leaders committed to step up TB elimination efforts, with improved TB case finding and expanded use of TB preventive treatment (TPT) identified as key interventions in the global ‘End TB strategy’.…”

“…Leprosy rates in Kiribati, and South Tarawa in particular, are also among the highest in the world (>200 cases/100 000 population, compared with the WHO elimination threshold of 10/100 000 population) and have been rising rapidly after a nadir in the late 1990s when elimination efforts were discontinued. 2 Modelling studies done in Kiribati indicate that a single population-wide active case finding intervention, combined with ‘universal leprosy prophylaxis’ using single-dose rifampicin (SDR), could dramatically decrease leprosy prevalence with a sustained effect. 20 …”