Mycobacterium leprae transmission characteristics during the declining stages of leprosy incidence: A systematic review

Background Leprosy is an infectious disease caused by Mycobacterium leprae. As incidence begins to decline, the characteristics of new cases shifts away from those observed in highly endemic areas, revealing potentially important insights into possible ongoing sources of transmission. We aimed to investigate whether transmission is driven mainly by undiagnosed and untreated new leprosy cases in the community, or by incompletely treated or relapsing cases. Methodology/Principal findings A literature search of major electronic databases was conducted in January, 2020 with 134 articles retained out of a total 4318 records identified (PROSPERO ID: CRD42020178923). We presented quantitative data from leprosy case records with supporting evidence describing the decline in incidence across several contexts. BCG vaccination, active case finding, adherence to multidrug therapy and continued surveillance following treatment were the main strategies shared by countries who achieved a substantial reduction in incidence. From 3950 leprosy case records collected across 22 low endemic countries, 48.3% were suspected to be imported, originating from transmission outside of the country. Most cases were multibacillary (64.4%) and regularly confirmed through skin biopsy, with 122 cases of suspected relapse from previous leprosy treatment. Family history was reported in 18.7% of cases, while other suspected sources included travel to high endemic areas and direct contact with armadillos. None of the countries included in the analysis reported a distinct increase in leprosy incidence in recent years. Conclusions/Significance Together with socioeconomic improvement over time, several successful leprosy control programmes have been implemented in recent decades that led to a substantial decline in incidence. Most cases described in these contexts were multibacillary and numerous cases of suspected relapse were reported. Despite these observations, there was no indication that these cases led to a rise in new secondary cases, suggesting that they do not represent a large ongoing source of human-to-human transmission.

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Public Assessment of Social and Economic Rehabilitation Component of Leprosy Control Programmes in Anambra and Ebonyi States of Southeast Nigeria

World Family Medicine Journal/Middle East Journal of Family Medicine ◽

10.5742/mewfm.2015.92674 ◽

2015 ◽

Vol 13 (3) ◽

pp. 20-33 ◽

Cited By ~ 1

Author(s):

Ignatius Uche Nwankwo

Keyword(s):

Control Programmes ◽

Leprosy Control

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Death by attrition: a hypothesis for wave mortality of subalpine Abiesbalsamea

Canadian Journal of Forest Research ◽

10.1139/x86-102 ◽

1986 ◽

Vol 16 (3) ◽

pp. 591-596 ◽

Cited By ~ 21

Author(s):

Peter J. Marchand ◽

France L. Goulet ◽

Thomas C. Harrington

Keyword(s):

Wave Front ◽

Energy Demand ◽

Substantial Reduction ◽

Leading Edge ◽

Compact Zone ◽

Fold Reduction ◽

Xylem Discoloration ◽

Substantial Decline ◽

Individual Trees ◽

Mature Stands

Wave mortality in subalpine Abies forests of the northeastern United States is characterized by the progressive dieback of overstory dominants in a compact zone that advances systematically through mature stands and is followed by vigorous regeneration of the overstory species. The principal driving force for this dieback appears to be exposure at the edge of canopy gaps to very high winds. In this study, individual trees at the leading edge of a dieback front and trees in a thinned plot within the mature stand downwind of the advancing wave both experienced a substantial decline in foliage mass and, consequently, in prebudbreak foliar starch pool over a 2-year period. In the case of the thinned stand, this reduction was attributed to a large increase in wintertime green litter fall. Increased exposure at the wave front and in the thinned stand also resulted in a dramatic increase in root damage relative to control trees. Coincidental to breakage of roots, root xylem discoloration (attributed to wounding and invasion by root pathogens) was greater on trees at the wave front than on trees in the mature zone. Loss of active foliage and roots was accompanied by a two- to five-fold reduction in annual wood increment among dieback zone trees. These data suggest that exposed trees, which suffer a substantial reduction in crown size and foliage carbohydrate pool in an environment where growth is marginal to begin with, may not be able to keep up with the increased energy demand for root and foliage turnover and eventually suffer death by attrition of both tissues.

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Long-lasting insecticidal nets retain bio-efficacy after five years of storage: implications for malaria control programmes

10.21203/rs.2.17717/v3 ◽

2020 ◽

Author(s):

Jeremiah John Musa ◽

Sarah Moore ◽

Jason Moore ◽

Emmanuel Mbuba ◽

Edgar Mbeyela ◽

...

Keyword(s):

Relative Humidity ◽

Malaria Control ◽

Blood Feeding ◽

Sensu Stricto ◽

World Health ◽

Small Scale ◽

Feeding Inhibition ◽

Control Programmes ◽

Endemic Areas ◽

Long Lasting Insecticidal Nets

Abstract Background: Long-lasting insecticidal nets (LLINs) are the most sustainable and effective malaria control tool currently available. Global targets are for 80% of the population living in malaria endemic areas to have access to (own) and use a LLIN. However, current access to LLINs in endemic areas is 56% due to system inefficiencies and budget limitations. Thus, cost-effective approaches to maximize access to effective LLINs in endemic areas are required. This study evaluated whether LLINs that had been stored for five years under manufacturer’s recommended conditions may be optimally effective against Anopheles mosquitoes, to inform malaria control programmes and governments on the periods over which LLINs may be stored between distributions, in an effort to maximize use of available LLINs. Methods: Standard World Health Organization (WHO) bioassays (cone and tunnel test) were used to evaluate the bio-efficacy and wash resistance of Olyset® and DawaPlus® 2.0 (rebranded Tsara® Soft) LLINs after five years of storage at 25°C to 33.4°C and 40% to 100% relative humidity. In addition, a small scale Ifakara Ambient Chamber test (I-ACT) was conducted to compare the bio-efficacy of one long stored LLINs to one new LLIN of the same brand, washed or unwashed. LLINs were evaluated using laboratory reared fully susceptible Anopheles gambiae sensu stricto (s.s.) (Ifakara strain) and pyrethroid resistant Anopheles arabiensis (Kingani strain). Results: After five years of storage, both unwashed and washed, Olyset® and DawaPlus® 2.0 (Tsara® Soft) LLINs passed WHO bio-efficacy criteria on knockdown (KD60) ≥95%, 24-hour mortality ≥80% and ≥90% blood-feeding inhibition in WHO assays against susceptible An. gambiae s.s. DawaPlus® 2.0 LLINs also passed combined WHO bioassay criteria against resistant An. arabiensis. Confirmatory I-ACT tests using whole nets demonstrated that long-stored LLINs showed higher efficacy than new LLINs on both feeding inhibition and mortality endpoints against resistant strains.Conclusions: Even after long-term storage of around 5 years, both Olyset® and DawaPlus® 2.0 LLINs remain efficacious against susceptible Anopheles mosquitoes at optimal storage range of 25°C to 33.4°C for temperature and 40% to 100% relative humidity measured by standard WHO methods. DawaPlus® 2.0 (Tsara® Soft) remained efficacious against resistant strain.

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DAPSONE RESISTANCE IN A Mycobacterium leprae ISOLATE WITH TWO POINT MUTATIONS IN folP GENE FROM A LEPROSY PATIENT

Indonesian Journal of Tropical and Infectious Disease ◽

10.20473/ijtid.v3i2.218 ◽

2016 ◽

Vol 3 (2) ◽

pp. 108

Author(s):

Dinar Ardiaty ◽

Ratna Wahyuni ◽

Cita Prakoeswa ◽

Rasyidin Abdullah ◽

Indropo Agusni ◽

...

Keyword(s):

Drug Resistance ◽

Point Mutations ◽

Control Policy ◽

Control Program ◽

Skin Lesions ◽

Double Mutation ◽

South Sulawesi ◽

Leprosy Case ◽

Morphological Index ◽

Leprosy Control

Drug resistance in leprosy is important for Leprosy Control Program, since the WHO-Multidrug regiment (MDT) has been used for global treatment of leprosy for more than two decades already. A Dapsone resistance case in a Multibacillary (MB) leprosy case is reported. The patient was diagnosed and treated in Tajuddin Chalid Hospital Makassar, South Sulawesi. Previously he was treated in a health center at South Sulawesi and was given a treatment for one year, before referred to the hospital. The leprosy skin lesions are still active with erythematous skin lesions and thickened ear lobe. Bacteriological examination was positive for Acid Fast Bacilli, the Bacterial Index was 3+ and the Morphological Index was 1%. The specimens of M.leprae isolation was sent to the Institute of Tropical Disease Surabaya for drug resistance study. Using the Lp1-2 and Lp3-4 nested primers, PCR test was positive for M.leprae.Sequencing result for folP gene showed a double mutation at codon 53 (ACC / Threonin ) which become (AGG / Arginine). Simultaneous mutation at two nucleotides at one codon has never been reported in Indonesia before and this phenomenon is important for leprosy control policy.

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Dapsone-resistant Leprosy and Its Implications for Leprosy Control Programmes

Leprosy Review ◽

10.5935/0305-7518.19770010 ◽

1977 ◽

Vol 48 (2) ◽

Author(s):

J. M. H. PEARSON ◽

J. A. CAP ◽

G. S. HAILE ◽

R. J. W. REES

Keyword(s):

Control Programmes ◽

Leprosy Control

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Flow charts for use in leprosy control programmes

Leprosy Review ◽

10.5935/0305-7518.19860021 ◽

1986 ◽

Vol 57 (2) ◽

Author(s):

S. J. NICKLESS

Keyword(s):

Control Programmes ◽

Flow Charts ◽

Leprosy Control

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Pediatric Leprosy Profile in the Postelimination Era: A Study from Surabaya, Indonesia

American Journal of Tropical Medicine and Hygiene ◽

10.4269/ajtmh.21-0458 ◽

2022 ◽

Author(s):

Cita Prakoeswa ◽

Novianti Reza ◽

Medhi Alinda ◽

M. Listiawan ◽

Hok Bing Thio ◽

...

Keyword(s):

Retrospective Study ◽

Erythema Nodosum ◽

Elimination Rate ◽

Mycobacterium Leprae ◽

Tertiary Hospital ◽

Disease Prevalence ◽

Erythema Nodosum Leprosum ◽

Common Problems ◽

Endemic Areas ◽

Frequent Exposure

Children who live in leprosy-endemic areas are susceptible to infection due to early and frequent exposure to Mycobacterium leprae. Indonesia is on the verge of eliminating this disease (prevalence rate < 1/10,000 population), but pediatric leprosy continues to occur in low-endemic areas. This study aimed to evaluate pediatric leprosy over a decade in a tertiary hospital in Surabaya, Indonesia. A retrospective study of leprosy in children under 15 years old between 2010 and 2019 was conducted in the Morbus Hansen Division, Outpatient Clinic at Dr. Soetomo Hospital in Surabaya, Indonesia. Seventy pediatric leprosy cases were identified between 2010 and 2019, consisting of 58 multibacillary (MB)-type cases and 12 paucibacillary (PB)-type cases. Slit skin smear (SSS) was positive in 26 cases. There were two cases of grade-2 disability and 15 cases of leprosy reaction (erythema nodosum leprosum) in children at the time of diagnosis. There was an insignificant decline in the number of pediatric leprosy cases in the last 10 years. Cases and disabilities in children were found in some leprosy pocket areas even though the national elimination rate has been achieved. MB infections, disability, and treatment defaults were common problems in pediatric leprosy.

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Leprosy: Need Early Detection And Early Treatment

Medicine Today ◽

10.3329/medtoday.v24i1.14116 ◽

2013 ◽

Vol 24 (1) ◽

pp. 44-47 ◽

Cited By ~ 1

Author(s):

Lubna Khondker ◽

Md Abdul Wahab ◽

Md Shirajul Islam Khan ◽

Samaresh Chandra Hazra

Keyword(s):

Peripheral Nerves ◽

Public Health Problem ◽

Infectious Agent ◽

Mycobacterium Leprae ◽

Bacterial Disease ◽

Abnormal Immune Response ◽

History Of ◽

Medicine Today ◽

Genetically Determined ◽

Leprosy Control

Leprosy is the most ancient bacterial disease in the history of mankind. It remains still public health problem in the countries where it is endemic. Leprosy (Hansens disease) is a chronic infectious disease which is diagnosable and curable if recognized early and treated adequately. The infectious agent of leprosy is Mycobacterium leprae which is only bacteria to infect peripheral nerves. Leprosy is characterized by a variety of abnormal immune response. It depends on the integrity of the hosts specific CMI response to the M. leprae and it may be genetically determined. Antileprotic multidrugs therapy (MDT) as recommended by WHO is now the standard and accepted method for leprosy control. Leprosy can not be completely rooted out with physicians, control offices, leprosaria and propaganda; it will disappear when the economic and cultural factors change, because leprosy is the thermometer of civilization. DOI: http://dx.doi.org/10.3329/medtoday.v24i1.14116 Medicine TODAY Vol.24(1) 2012 pp.44-47

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