Neglected tropical diseases among the Association of Southeast Asian Nations (ASEAN): overview and update.

The ten member states of the Association of Southeast Asian Nations (ASEAN) constitute an economic powerhouse, yet these countries also harbor a mostly hidden burden of poverty and neglected tropical diseases (NTDs). Almost 200 million people live in extreme poverty in ASEAN countries, mostly in the low or lower middle-income countries of Indonesia, the Philippines, Myanmar, Viet Nam, and Cambodia, and many of them are affected by at least one NTD. However, NTDs are prevalent even among upper middle-income ASEAN countries such as Malaysia and Thailand, especially among the indigenous populations. The three major intestinal helminth infections are the most common NTDs; each helminthiasis is associated with approximately 100 million infections in the region. In addition, more than 10 million people suffer from either liver or intestinal fluke infections, as well as schistosomiasis and lymphatic filariasis (LF). Intestinal protozoan infections are widespread, while leishmaniasis has emerged in Thailand, and zoonotic malaria (Plasmodium knowlesi infection) causes severe morbidity in Malaysia. Melioidosis has emerged as an important bacterial NTD, as have selected rickettsial infections, and leptospirosis. Leprosy, yaws, and trachoma are still endemic in focal areas. Almost 70 million cases of dengue fever occur annually in ASEAN countries, such that this arboviral infection is now one of the most common and economically important NTDs in the region. A number of other arboviral and zoonotic viral infections have also emerged, including Japanese encephalitis; tick-borne viral infections; Nipah virus, a zoonosis present in fruit bats; and enterovirus 71 infection. There are urgent needs to expand surveillance activities in ASEAN countries, as well as to ensure mass drug administration is provided to populations at risk for intestinal helminth and fluke infections, LF, trachoma, and yaws. An ASEAN Network for Drugs, Diagnostics, Vaccines, and Traditional Medicines Innovation provides a policy framework for the development of new control and elimination tools. Together with prominent research institutions and universities, the World Health Organization (WHO), and its regional offices, these organizations could implement important public health improvements through NTD control and elimination in the coming decade.

Leprosy: a glossary.

Leprosy continues to afflict residents from a number of countries in Africa, South America, and southeast Asia, despite the marked reduction in the number of cases of leprosy worldwide, after the introduction of the multidrug regimens as recommended by the World Health Organization (WHO-MDT). With the increasing immigration of individuals from risk areas to Europe and the United States, knowledge of the basic concepts of leprosy would be helpful to clinicians caring for immigrants in nonendemic areas. We present a comprehensive, updated, and critical glossary of the most relevant terms related to leprosy.

Characteristic mutations found in the ML0411 gene of Mycobacterium leprae isolated in Northeast Asian countries.

Genome analysis of Mycobacterium leprae strain Kyoto-2 in this study revealed characteristic nucleotide substitutions in gene ML0411, compared to the reference genome M. leprae strain TN. The ML0411 gene of Kyoto-2 had six SNPs compared to that of TN. All SNPs in ML0411 were non-synonymous mutations that result in amino acid replacements. In addition, a seventh SNP was found 41 bp upstream of the start codon in the regulatory region. The seven SNP sites in the ML0411 region were investigated by sequencing in 36 M. leprae isolates from the Leprosy Research Center in Japan. The SNP pattern in 14 of the 36 isolates showed similarity to that of Kyoto-2. Determination of the standard SNP types within the 36 stocked isolates revealed that almost all of the Japanese strains belonged to SNP type III, with nucleotide substitutions at position 14676, 164275, and 2935685 of the M. leprae TN genome. The geographical distribution pattern of east Asian M. leprae isolates by discrimination of ML0411 SNPs was investigated and interestingly turned out to be similar to that of tandem repeat numbers of GACATC in the rpoT gene (3 copies or 4 copies), which has been established as a tool for M. leprae genotyping. All seven Korean M. leprae isolates examined in this study, as well as those derived from Honshu Island of Japan, showed 4 copies of the 6-base tandem repeat plus the ML0411 SNPs observed in M. leprae Kyoto-2. They are termed Northeast Asian (NA) strain of M. leprae. On the other hand, many of isolates derived from the Okinawa Islands of Japan and from the Philippines showed 3 copies of the 6-base tandem repeat in addition to the M. leprae TN ML0411 type of SNPs. These results demonstrate the existence of M. leprae strains in Northeast Asian region having characteristic SNP patterns.

Elimination of neglected tropical diseases in the South-East Asia Region of the World Health Organization.

The neglected tropical diseases (NTDs), which affect the very poor, pose a major public health problem in the South-East Asia Region of the World Health Organization (WHO). Although more than a dozen NTDs affect the region, over the past five years four of them in particular - leprosy, lymphatic filariasis, visceral leishmaniasis (kala-azar) and yaws - have been targeted for elimination. These four were selected for a number of reasons. First, they affect the WHO South-East Asia Region disproportionately. For example, every year around 67% of all new leprosy cases and 60% of all new cases of visceral leishmaniasis worldwide occur in countries of the region, where as many as 850 million inhabitants are at risk of contracting lymphatic filariasis. In addition, several epidemiological, technological and historical factors that are unique to the region make each of these four diseases amenable to elimination. Safe and effective tools and interventions to achieve these targets are available and concerted efforts to scale them up, singly or in an integrated manner, are likely to lead to success. The World Health Assembly and the WHO Regional Committee, through a series of resolutions, have already expressed regional and global commitments for the elimination of these diseases as public health problems. Such action is expected to have a quick and dramatic impact on poverty reduction and to contribute to the achievement of the Millennium Development Goals. This paper reviews the policy rationale for disease control in the WHO South-East Asia Region, the progress made so far, the lessons learnt along the way, and the remaining challenges and opportunities.

[Leprosy services following elimination in WPRO and SEARO regions].

The elimination of leprosy with the advent of multidrug therapy (MDT) is one of the success stories in public health. Elimination will be achieved in the regions of Western pacific and South-East Asia in near future. A biregional consultation between the WHO South-East Asia and Western Pacific regions was held in the end of 2004 in Manila, the Philippines. A strategy document was developed during the consultation, to sustain quality leprosy services in Asia and the Pacific beyond 2005, and to further reduce the leprosy burden. The main strategy involves timely detection of new cases, multidrug treatment, and the key element of integration of leprosy services into general health services.

Trends in leprosy case detection worldwide since 1985.

Trends in case detection and case detection rate (CDR) since 1985 are described at regional and national levels. Annual case detection by WHO Region was available for 1994-2000. Using different sources, complete time series for case detection were constructed for 1985-1998 for a group of 33 endemic countries cumulatively (top 33), and for 14 individual countries (top 14). Population statistics were used to derive CDRs. India contributed 79% to global case detection in 1998. Africa, the Americas and South-East Asia each contributed about 30% when India is excluded. During 1994-2000, case detection did not decrease in these three WHO Regions. The 33 countries contributed 99% and 98% to global case detection in 1994 and 1998, respectively. Cumulative case detection for the top 33 minus India gradually increased, overall almost doubling. The contribution of the top 14 to case detection of the top 33 hardly changed over time, equalling 96% in 1998 (81% when India is excluded). In terms of annual case detection, Brazil was always ranked second after India; it accounted for 27% of 1998 case detection in the top 33 except India. In 1998, seven of the top 14 countries--including India and Brazil--had CDRs above 2 per 10,000. The CDR did not exceed 1 per 10,000 for the other half. Decreasing tendencies in CDR, either for the whole period or in the 1990s, are observed for four of the top 14 countries (Guinea and three Western Pacific countries: China, Vietnam and the Philippines). In conclusion, there is no general decline in case detection to date, and several important countries still have high CDRs. Prevalence is an irrelevant indicator for monitoring epidemiological changes in leprosy. Trends in the transmission and incidence of leprosy are still completely unclear, necessitating further research. The target to eliminate leprosy as a public health problem, defined as a prevalence of less than 1 per 10,000, is therefore also an inadequate yardstick for decision making on leprosy control.

Elimination of leprosy as a public health problem: progress and prospects.

Leprosy is still an important problem in about 80 countries of Asia, Africa and Latin America, some 2.4 million persons being estimated to have the disease in 1994. The WHO-recommended standard multidrug therapy (MDT) was introduced in the 1980s and has been shown to be effective in combating the disease. Experiences based on many thousands of patients treated with MDT over the past decade indicate extremely low relapse rates (cumulative relapse rates around 1%). By the end of 1993, some 5.6 million patients had been cured, and the global cumulative MDT coverage of registered patients had reached 89%. The number of registered cases fell from 5.4 million in 1985 to 1.7 million in 1994. The significant progress made in leprosy control enabled the World Health Assembly in 1991 to set a goal for eliminating leprosy as a public health problem by the year 2000. One important epidemiological factor is that leprosy is very unevenly distributed: 80% of the problem is confined to only five countries and 92% to just 25 countries. The elimination strategy envisages identifying and treating with MDT a total of about 5 million cases from 1994 to the year 2000. The cost of dealing with these cases has been estimated at US$ 420 million, including US$ 150 million for the drugs.

PIP: The World Health Organization-recommended standard multidrug therapy (MDT) against leprosy was introduced in the 1980s and has since been extremely effective against the disease. The number of registered cases worldwide fell from 5.4 million in 1985 to 1.7 million in 1994, the global cumulative MDT coverage of registered patients was at 89%, and the cumulative relapse rates have been low at around 1%. Leprosy, however, remains an important problem in about 80 countries in Asia, Africa, and Latin America, with 2.4 million people estimated to be with the disease in 1994. 80% of the problem is confined to five countries and 92% to just 25 countries. The prevalence of leprosy is therefore far from evenly distributed. The largest numbers of registered cases are in India, Brazil, Indonesia, and Myanmar at 995,285, 223,539, 70,961, and 56,410, respectively. The highest prevalences per 10,000 population are in Brazil, Myanmar, Chad, and India at 14.30, 12.98, 12.43, and 11.34, respectively. Progress against leprosy prompted the World Health Assembly in 1991 to establish the goal of eliminating leprosy as a public health problem by the year 2000. Eliminated is defined as less than one case per 10,000 population. The strategy to that end envisages identifying and treating with MDT about five million cases of leprosy from 1994 to the year 2000 at an estimated cost of $420 million, including $150 million for the drugs.

[Infection by the human immunodeficiency virus and leprosy]. / L'infection par le virus de l'immunodéficience humaine et lèpre.

The author is reviewing the literature about the association HIV infection and leprosy. So he concludes: 1) there is no correlation between leprosy incidence and HIV infection incidence, despite similarity as far as immuno-system is concerned. 2) Effect of HIV infection on leprosy demands further studies of nervous leprosy pathology. 3) Tendency to increase of such and association is foreseeable, speaking of epidemiocity in developing countries as well as in leprosy foci in Southern Asia and India.