General Surveillance Research Articles

Asymptomatic De Novo Inflammatory Bowel Disease Late After Liver Transplantation for Primary Sclerosing Cholangitis: A Case Report

Guidelines recommend colonoscopy screening for possible asymptomatic inflammatory bowel disease (IBD) in all patients diagnosed with primary sclerosing cholangitis (PSC). PSC-IBD warrants regular dysplasia-surveillance colonoscopy. However, no consensus exists regarding follow-up colonoscopy in PSC patients without IBD who remain asymptomatic. We describe a 43-year-old female who had undergone liver transplantation (LT) due to advanced PSC. Previous colonoscopies had been normal. The post-transplantation course was uneventful, with no rejections and signs of PSC recurrence. Immunosuppression was by tacrolimus monotherapy. She was asymptomatic with normal inflammation markers. A protocol colonoscopy, performed as general dysplasia surveillance 8 years post-transplantation, revealed mucopurulent-covered small superficial ulcerations and erythema diffusely distributed from the cecal to sigmoid colon with intervening normal mucosa and rectal sparing. Histologic examination showed patchy chronic colitis with crypt architectural distortion and mild-moderate inflammation activity. Infection samples were negative. Findings complied with de novo IBD, type unclassified. In conclusion, the link between PSC and clinically silent IBD may manifest after the PSC diagnosis and even several years after LT. Given the increased colorectal cancer risk associated with PSC, IBD, and LT, repeat colonoscopy might be warranted in PSC patients without IBD at initial assessment, and also after LT.

Revised annual post‐market environmental monitoring (PMEM) report on the cultivation of genetically modified maize MON 810 in 2013 from Monsanto Europe S.A

Following a request from the European Commission, the Panel on Genetically Modified Organisms of the European Food Safety Authority (EFSA GMO Panel) assessed the results of the general surveillance activities contained in the revised annual post-market environmental monitoring (PMEM) report for the 2013 growing season of maize MON 810 provided by Monsanto Europe S.A. The supplied data do not indicate any unanticipated adverse effects on human and animal health or the environment arising from the cultivation of maize MON 810 cultivation in 2013. Similar methodological shortcomings to those observed in previous annual PMEM reports were identified in the analysis of farmer questionnaires and the conduct of the literature review. The EFSA GMO Panel therefore strongly reiterates its previous recommendations to improve the methodology of future annual PMEM reports on maize MON 810. The EFSA GMO Panel urges the applicant to consider how to make best use of the information recorded in national registers in order to optimise sampling for farmer questionnaires, reiterates its previous recommendations on insect resistance monitoring and continued screening, and requests to continue reviewing and discussing relevant scientific publications on possible adverse effects of maize MON 810 on rove beetles. Also, the EFSA GMO Panel encourages relevant parties to continue developing a methodological framework to use existing networks in the broader context of environmental monitoring.

Can general surveillance detect high priority pests in the Western Australian Grains Industry?

Initial detection of plant pests (includes diseases) is often made by the growers and consultants that work directly with crops; this form of detection is referred to as general surveillance. General surveillance activities have an important role in plant biosecurity for the early detection of pests and for demonstrating area freedom. In the Western Australian grains industry, reports of suspect high priority pests to the state Department of Agriculture and Food is the main form of general surveillance. There is little information on the level of knowledge of high priority pests in the grains industry in Western Australia and the ability of members to detect high priority pests if they were present. This study details a survey of members of the grains industry to determine their knowledge of the signs of high priority grains pests and the likelihood that they would detect a high priority pest if it were present in grain or crops. Knowledge of the signs of the high priority grain diseases, Karnal bunt and Barley stripe rust, were found to be higher than those of the high priority insect pests, Khapra beetle and Russian wheat aphid. A wide range of responses was collected from respondents’ self-rated likelihood of detecting each of these pests and diseases in crop or harvested grain. However, respondents were more confident in their ability to detect the two plant diseases than the two insect pests. The results of this study suggest that further training in recognition of the signs and symptoms of high priority grains pests is required to increase the ability of members of the grains industry to confidently detect and differentiate high priority pests from common pests in the course of routine activities.

How would high priority pests be reported in the Western Australian grains industry?

General surveillance activities have an important role in plant biosecurity for the early detection of pests (includes diseases) and for demonstrating area freedom. Currently general surveillance information for the grains industry in Western Australia is mainly collected though reports of suspect high priority pests to the state Department of Agriculture and Food (DAFWA). Little information is available on the likelihood that members of the grains industry would report a suspect high priority pest, where and who they report pests to, and the factors that influence their decisions to report pests. This study details a survey of members of the grains industry conducted to determine the reporting practices relating to plant pest and diseases in the grains industry. Results of the study indicate that growers preferentially report to agricultural consultants and the local DAFWA staff; whereas agricultural consultants and researchers are more likely to report to the DAFWA head office. Factors that influenced participants’ reporting of suspect high priority pests included the ability to eradicate the pest or disease, free examination of suspect samples and the desire for more information about high priority pests. The ranking of factors varied with the role the individual had in the grains industry.

Cohort Profile: Health Watch-a 30-year prospective cohort study of Australian petroleum industry workers.

Health Watch was established in 1980 at the University of Melbourne to ‘explore possible links between occupational experience in the [petroleum] industry’ and subsequent mortality and cancer incidence. There was concern that occupational exposure to fossil fuels could result in occupational cancers and it was anticipated that ‘well designed epidemiological studies, and carefully planned data bases’ were ‘capable of confirming or refuting such association’ rather than relying on clinician recognition of clusters. Health Watch was ‘designed to operate as a general health surveillance system’ comparable to a contemporary USA study funded by the American Petroleum Institute. Later reports expanded the aim to be ‘a prospective epidemiological study with the capacity to test specific hypotheses regarding the possible health consequences of occupationally determined exposure to hydrocarbon and other chemical substances’. This follows efforts by the industry’s occupational hygienists to link descriptive job categories to an index of hydrocarbon exposure. The main aims of tracking mortality and cancer incidence in the cohort have not changed over time, but subanalyses have been included e.g. for tanker drivers and for a group of men at a particular refinery. After an excess of lympho-haematopoetic (LH) cancer was identified, a case-control study was instituted to investigate whether benzene exposure was associated with this increased risk. This study was followed up in 2008 with a pooled analysis to identify which subtypes of LH cancer might be most strongly associated with benzene exposure. The industry has reduced benzene exposure over the period of the cohort. In 1999, the custodianship of the cohort was transferred to the University of Adelaide and then in 2005 to Monash University’s Centre for Occupational and Environmental Health in the Department of Epidemiology and Preventive Medicine, where it currently resides. The Australian Institute of Petroleum (AIP) has funded the relevant universities, including Monash University, to implement the study with funds from their member companies in the Australian petroleum industry. The study has an advisory committee that meets regularly and includes the relevant university investigators and trades union and company representatives. The committee is chaired by a representative of the participating companies on a rotating basis and the AIP provides the secretariat.

Assessing the efficacy of general surveillance for detection of incursions of livestock diseases in Australia

Australia, as a relatively isolated country with a high level of agricultural production, depends on, and has the opportunity to maintain, freedom from a range of important diseases of livestock. Occasional incursions of such diseases are generally detected by ‘passive’, general surveillance (GS). In current surveillance planning, a risk-based approach has been taken to optimising allocation of resources to surveillance needs, and having mapped the relative risk of introduction and establishment of diseases of concern, a means of mapping the efficacy of GS for their detection was required, as was a means of assessing the likely efficacy of options for improving GS efficacy if needed. This paper presents the structure and application of a tool for estimating the efficacy of Australia’s GS, using the example of foot and mouth disease (FMD). The GS assessment tool (GSAT) is a stochastic spreadsheet model of the detection, diagnosis and reporting of disease on a single infected farm. It utilises the output of an intraherd disease spread model to determine the duration and prevalence of infection on different types of farm. It was applied separately to each of twelve regions of Australia, demarcated by dominant livestock production practices. Each region supplied estimates of probabilities relevant to the detection of FMD, for each of fourteen farm types and all species susceptible to the disease. Outputs of the GSAT were the average probability that FMD on the farm would be detected (single farm sensitivity), the average time elapsed from incursion of the disease to the chief veterinary officer (CVO) being notified (time to detection), and the number of average properties that would need to be infected before the CVO could be 95% confident of detecting at least one. The median single farm sensitivity for FMD varied among regions from 0.23 to 0.52, the median time to detection from 20 to 33 days, and the number of properties infected for 95% confidence of detecting at least one from 4 to 12. The GSAT has proved a valuable tool in planning surveillance for detection of exotic livestock disease in Australia, and it provides a practical example of the use of probabilistic modelling to answer important questions in the face of imperfect information.

A Framework for Developing a Curriculum Regarding Autism Spectrum Disorders for Primary Care Providers.

The prevalence of Autism Spectrum Disorders (ASDs) has increased and varies across age groups. Thus there is an increasing need for educational opportunities for General Practitioners (GPs) and other Primary Care providers to help in early identification and referral to specialist services. An earlier survey of GPs in New South Wales (Australia) demonstrated two broad domains for educational activities: (1) a general knowledge (important for early identification and referral) and (2) surveillance (important for ongoing management). To seek further evidence to these domains and synthesize the important contents for educational programs for GPs. We conducted a (1) Confirmatory Factor Analysis (CFA) on our original survey data and (2) systematic review of the literature to identify important educational topics, using a life cycle approach. CFA and literature review support theoretical framework of two domains. Alerts and red flags for ASDs, knowledge of simple surveillance tools, communication of diagnosis with parents, referral pathways particularly to speech pathologists before a formal diagnosis is confirmed, and appreciation of vulnerabilities for identifying supports were important in the general knowledge domain, while supporting the families through transition points such as from pre-school to school entry, secondary school and adolescence, role of psychopharmacology such as medications for sleep issues, and for common co-morbidities of anxiety were important in the surveillance dimension. GP supervisors and medical and nursing educators can use findings from this paper for developing structured learning activities for training primary health care workforce regarding ASD's.

Understanding influenza vaccine protection in the community: An assessment of the 2013 influenza season in Victoria, Australia

BackgroundThe influenza virus undergoes frequent antigenic drift, necessitating annual review of the composition of the influenza vaccine. Vaccination is an important strategy for reducing the impact and burden of influenza, and estimating vaccine effectiveness (VE) each year informs surveillance and preventative measures. We aimed to describe the influenza season and to estimate the effectiveness of the influenza vaccine in Victoria, Australia, in 2013. MethodsRoutine laboratory notifications, general practitioner sentinel surveillance (including a medical deputising service) data, and sentinel hospital admission surveillance data for the influenza season (29 April to 27 October 2013) were collated in Victoria, Australia, to describe influenza-like illness or confirmed influenza during the season. General practitioner sentinel surveillance data were used to estimate VE against medically-attended laboratory confirmed influenza. VE was estimated using the case test negative design as 1−adjusted odds ratio (odds of vaccination in cases compared with controls)×100%. Cases tested positive for influenza while non-cases (controls) tested negative. Estimates were adjusted for age group, week of onset, time to swabbing and co-morbidities. ResultsThe 2013 influenza season was characterised by relatively low activity with a late peak. Influenza B circulation preceded that of influenza A(H1)pdm09, with very little influenza A(H3) circulation. Adjusted VE for all influenza was 55% (95%CI: −11, 82), for influenza A(H1)pdm09 was 43% (95%CI: −132, 86), and for influenza B was 56% (95%CI: −51, 87) Imputation of missing data raised the influenza VE point estimate to 64% (95%CI: 13, 85). ConclusionsClinicians can continue to promote a positive approach to influenza vaccination, understanding that inactivated influenza vaccines prevent at least 50% of laboratory-confirmed outcomes in hospitals and the community.

Incidence and hospitalisation rates of Lyme borreliosis, France, 2004 to 2012.

Lyme borreliosis (LB) has become a major concern recently, as trends in several epidemiological studies indicate that there has been an increase in this disease in Europe and America over the last decade. This work provides estimates of LB incidence and hospitalisation rates in France. LB data was obtained from the Sentinelles general practitioner surveillance network (2009–2012) and from the Programme de Médicalisation des Systèmes d’Information (PMSI) data processing centre for hospital discharges (2004–09). The yearly LB incidence rate averaged 42 per 100,000 inhabitants (95% confidence interval (CI): 37–48), ranging from 0 to 184 per 100,000 depending on the region. The annual hospitalisation rate due to LB averaged 1.55 per 100,000 inhabitants (95% CI: 1.42–1.70). Both rates peaked during the summer and fall and had a bimodal age distribution (5–10 years and 50–70 years). Healthcare providers should continue to invest attention to prompt recognition and early therapy for LB, whereas public health strategies should keep promoting use of repellent, daily checks for ticks and their prompt removal.

Integration of prior knowledge into dense image matching for video surveillance

Abstract. Three-dimensional information from dense image matching is a valuable input for a broad range of vision applications. While reliable approaches exist for dedicated stereo setups they do not easily generalize to more challenging camera configurations. In the context of video surveillance the typically large spatial extent of the region of interest and repetitive structures in the scene render the application of dense image matching a challenging task. In this paper we present an approach that derives strong prior knowledge from a planar approximation of the scene. This information is integrated into a graph-cut based image matching framework that treats the assignment of optimal disparity values as a labelling task. Introducing the planar prior heavily reduces ambiguities together with the search space and increases computational efficiency. The results provide a proof of concept of the proposed approach. It allows the reconstruction of dense point clouds in more general surveillance camera setups with wider stereo baselines.

Harmonizing influenza primary-care surveillance in the United Kingdom: piloting two methods to assess the timing and intensity of the seasonal epidemic across several general practice-based surveillance schemes.

General Practitioner consultation rates for influenza-like illness (ILI) are monitored through several geographically distinct schemes in the UK, providing early warning to government and health services of community circulation and intensity of activity each winter. Following on from the 2009 pandemic, there has been a harmonization initiative to allow comparison across the distinct existing surveillance schemes each season. The moving epidemic method (MEM), proposed by the European Centre for Disease Prevention and Control for standardizing reporting of ILI rates, was piloted in 2011/12 and 2012/13 along with the previously proposed UK method of empirical percentiles. The MEM resulted in thresholds that were lower than traditional thresholds but more appropriate as indicators of the start of influenza virus circulation. The intensity of the influenza season assessed with the MEM was similar to that reported through the percentile approach. The MEM pre-epidemic threshold has now been adopted for reporting by each country of the UK. Further work will continue to assess intensity of activity and apply standardized methods to other influenza-related data sources.

The Dimensionality of Language Ability in Four-Year-Olds: Construct Validation of a Language Screening Tool

The Norwegian government recommends a systematic language assessment of all four-year-olds as part of the general health surveillance program for the purpose of identifying children at risk of language delay. This study aimed to investigate the construct validity of the recommended language screening tool called LANGUAGE4 [SPRÅK4] by first examining the dimensionality of the underlying construct of the tool, after which the concurrent convergent validity was established by regressing an external language factor, defined by four standardized language tests, on a single higher-order factor. The findings provide support for a higher-order model with one general language factor, suggesting that a large amount of the variance in LANGUAGE4 is attributable to a single common factor at the second-order level. Furthermore, this single factor explained a considerable amount of the variance in the external language factor. Our findings are interpreted as support for satisfactory construct validity of LANGUAGE4.

Infancy predictors of hyperkinetic and pervasive developmental disorders at ages 5-7years: results from the Copenhagen Child Cohort CCC2000.

Epidemiological studies infancy predictors of mental disorders are scarce. The study is part of a longitudinal birth-cohort study, The Copenhagen Child Cohort CCC2000. Infant mental health and development and mother-infant relations were assessed by community health nurses from birth to age 10months. Data on the perinatal period were obtained from Danish National Registers. Mental health outcome at age 5-7years was investigated in 1,585 children who were assessed by the Developmental and Well-Being Assessment (DAWBA) and diagnosed according to the ICD-10. Predictors of autism spectrum disorders were problems of oral-motor development OR 5.02 (95% CI: 1.63-15.42) and overall development OR 4.24 (95% CI: 1.35-13.33). A deviant pattern of activity and interests were predictive of autism spectrum disorder, OR 5.34 (95% CI 1.45-19.70) and hyperkinetic disorder, OR 4.71 (95% CI: 1.28-17.39). Hyperkinetic disorder was furthermore predicted by mother-infant relationship problems, OR 8.07 (95% CI: 2.90-22.47). The significant associations between infant developmental problems and autism spectrum disorders persisted in multiple logistic regression analyses controlled for maternal psychological problems and mother-infant relationship problems, OR 3.21 (95% CI: 1.09-9.45). Mother-infant relationship problems remained strongly associated to hyperkinetic disorders in the multivariate analyses controlled for child development problems and maternal psychological problems, OR 5.20 (95% CI: 1.55-17.47). No significant infancy predictors were found regarding emotional and behavioural disorders at age 5-7years. Predictors of autism spectrum/pervasive developmental disorders and hyperkinetic disorders at child age 5-7years were identified between birth and child age 10months in community health settings. The study results suggest potential areas of early preventive intervention, which have to be further explored regarding the psychometric qualities of the identification of infants at risk, and concerning methods to handle and intervene towards these children in the general child health surveillance.

Spatial outbreak detection based on inference principles for multivariate surveillance

Spatial surveillance is a special case of multivariate surveillance. Thus, in this review of spatial outbreak methods, the relation to general multivariate surveillance approaches is discussed. Different outbreak models are useful for different aims. First, it makes a great difference which spreading pattern is of main interest to detect. We will discuss methods for the detection of (i) spatial clusters of increased incidence; (ii) increased incidence at only one (unknown) location; (iii) simultaneous increase at all locations; and (iv) outbreaks with a time lag between the onsets in different regions. The sufficient reduction was used to find likelihood ratio methods for some of these spreading patterns. Second, an alternative to the common assumption of a step change to an increased incidence level is suggested. The assumption is sometimes too restrictive and errors in the estimation of the baseline have great influence. Instead, a robust nonparametric model is suggested. The seasonal variation of influenza in Sweden is used as an example. Here, the outbreak was characterized by a monotonic increase following the constant non-epidemic level. The semi-parametric generalized likelihood ratio surveillance method used for this application is described. Third, evaluation metrics are discussed. Evaluation in spatial and other multivariate surveillance requires special consideration.

안전한 보안 감시 시스템을 위한 효율적인 접근 제어 기법

사회 안전 서비스 제공을 위한 보안 감시 시스템이 보편화되어, 보안 감시 시스템에 대한 접근성이 확대되고, 향상되는 만큼 안정성 확보를 위한 접근제어 기법이 요구된다. ONVIF(Open Network Video Interface Forum)에서 제정하는 표준은 보안 감시용 스마트 카메라의 호환성을 목적으로 만든 표준으로, 클라이언트에게 제공될 웹서비스의 프레임워크를 정의하고 있다. 본 논문에서는 ONVIF 표준을 따르는 보안 감시 카메라 네트워크에서 안전한 시스템 접근을 위하여 웹 서비스의 정보 보호 기법을 수용하고, 웹서비스의 안전한 제공을 위한 효율적인 접근 제어 모델을 제안 한다. In recent general social surveillance systems, secure access control mechanism is needed. ONVIF establishes standards for interoperability between cameras and defines web service framework for it. In this paper we present an efficient attribute based access control mechanism for surveillance system networks which follow the ONVIF standards. It accommodates web service information security techniques and provides efficient secure access control.

Post-release monitoring: the Brazilian system, its aims and requirements for information

The Brazilian National Biosafety Committee approved in 2011 a new post release monitoring system for environmental releases of genetically modified organisms. It has a number of novel features in comparison with other established or proposed systems. The new system also allows the proponent to ask for monitoring exemption. General surveillance forms the basis of the monitoring system, similar to the European model, but differs markedly in the way it operates. While the European proposal is based on monitoring measurable variables extracted from environmental observations, from baselines previously established for multiple protection targets, the Brazilian system uses direct alerts of damage, without the aid of baseline values. The strength of the Brazilian form of monitoring is the possibility of generating an information network with the effective participation of many actors from the monitored area. A network constituted by highly qualified members, as proposed elsewhere, is too complex and unrealistic in Brazil and in many other countries. In conclusion, the Brazilian monitoring system is flexible and can be adjusted to the Brazilian reality over the next years, as a response to the ever growing experience in monitoring. It also meets the demands of the Brazilian society for transparency, rational use of resources, opportunity for national companies, and food and environmental biosafety.

Zero-inflated models for identifying disease risk factors when case detection is imperfect: Application to highly pathogenic avian influenza H5N1 in Thailand

Logistic regression models integrating disease presence/absence data are widely used to identify risk factors for a given disease. However, when data arise from imperfect surveillance systems, the interpretation of results is confusing since explanatory variables can be related either to the occurrence of the disease or to the efficiency of the surveillance system. As an alternative, we present spatial and non-spatial zero-inflated Poisson (ZIP) regressions for modelling the number of highly pathogenic avian influenza (HPAI) H5N1 outbreaks that were reported at subdistrict level in Thailand during the second epidemic wave (July 3rd 2004 to May 5th 2005). The spatial ZIP model fitted the data more effectively than its non-spatial version. This model clarified the role of the different variables: for example, results suggested that human population density was not associated with the disease occurrence but was rather associated with the number of reported outbreaks given disease occurrence. In addition, these models allowed estimating that 902 (95% CI 881–922) subdistricts suffered at least one HPAI H5N1 outbreak in Thailand although only 779 were reported to veterinary authorities, leading to a general surveillance sensitivity of 86.4% (95% CI 84.5–88.4). Finally, the outputs of the spatial ZIP model revealed the spatial distribution of the probability that a subdistrict could have been a false negative. The methodology presented here can easily be adapted to other animal health contexts.

The use of existing environmental networks for the post-market monitoring of GM crop cultivation in the EU.

The European Union (EU) Directive 2001/18/EC on the deliberate release of genetically modified organisms (GMOs) into the environment requires that both Case-Specific Monitoring (CSM) and General Surveillance (GS) are considered as post-market implementing measures. Whereas CSM is directed to monitor potential adverse effects of GMOs or their use identified in the environmental risk assessment, GS aims to detect un-intended adverse effects of GMOs or their use on human and animal health or the environment. Guidance documents on the monitoring of genetically modified (GM) plants from the Commission and EFSA clarify that, as appropriate, GS can make use of established routine surveillance practices. Networks involved in routine surveillance offer recognised expertise in a particular domain and are designed to collect information on important environmental aspects over a large geographical area. However, as the suitability of existing monitoring networks to provide relevant data for monitoring impacts of GMOs is not known, plant biotechnology companies developed an approach to describe the processes and criteria that will be used for selecting and evaluating existing monitoring systems. In this paper, the availability of existing monitoring networks for this purpose is evaluated. By cataloguing the existing environmental monitoring networks in the EU, it can be concluded that they can only be used, in the context of GMO cultivation monitoring, as secondary tools to collect baseline information.

Field evaluation of four widely used mosquito traps in Central Europe.

BackgroundTo monitor adult mosquitoes several trapping devices are available. These are differently constructed and use various mechanisms for mosquito attraction, thus resulting in different trapping sensitivities and efficacies for the various species. Mosquito monitoring and surveillance programs in Europe use various types of mosquito traps, but only a few comparisons have been conducted so far. This study compared the performance of four commercial trapping devices, which are commonly used in Europe.MethodsFour different traps, Biogents Sentinel trap (BG trap), Heavy Duty Encephalitis Vector Survey trap (EVS trap), Centres for Disease Control miniature light trap (CDC trap) and Mosquito Magnet Patriot Mosquito trap (MM trap) were compared in a 4 × 4 latin square study. In the years 2012 and 2013, more than seventy 24-hour trap comparisons were conducted at ten different locations in northern and southern Germany, representing urban, forest and floodplain biotopes.ResultsPer 24-hour trapping period, the BG trap caught the widest range of mosquito species, the highest number of individuals of the genus Culex as well as the highest number of individuals of the species Ochlerotatus cantans, Aedes cinereus/geminus, Oc. communis and Culex pipiens/torrentium. The CDC trap revealed best performance for Aedes vexans, whereas the MM trap was most efficient for mosquitoes of the genus Anopheles and the species Oc. geniculatus. The EVS trap did not catch more individuals of any genus or species compared to the other three trapping devices. The BG trap caught the highest number of individuals per trapping period in urban environments as well as in wet forest, while the CDC trap caught the highest number of individuals in the floodplain biotopes. Additionally, the BG trap was most efficient for the number of mosquito species in urban locations.ConclusionThe BG trap showed a significantly better or similar performance compared to the CDC, EVS or MM trap with regard to trapping efficacy for most common mosquito species in Germany, including diversity of mosquito species and number of mosquitoes per trapping period. Thus, the BG trap is probably the best solution for general monitoring or surveillance programs of adult mosquitoes in Central Europe.

Variable Number Tandem Repeats for Global Strain Typing and Strain Differentiation of Mycobacterium leprae

Leprosy is chronic granulomatous disease caused by Mycobacterium leprae and associated with the disability, stigma and discrimination to the affected individuals. Though often considered a disease of antiquity, it is found most commonly today in tropical and sub-tropical regions. Global efforts to eradicate leprosy have been largely successful in controlling its spread. Despite these efforts, the disease remains endemic countries emphasizing the need for greater scrutiny of its epidemiology. Strain typing and strain differentiation by Variable Number Tandem repeats (VNTR) could be useful in tracing origins and routes of infection, general leprosy surveillance and prevalence. Strain typing of Mycobacterium leprae by VNTR has been successfully carried out and predominance of leprosy bacilli in different geographical region also done by VNTR. In the present review, we reported global distribution M. leprae by Variable Number tandem repeats in systematic way to easy understanding of leprosy distribution.