Impact of immigration on tuberculosis epidemiology in a low-incidence country

GeneXpert analysis of bronchoalveolar lavage (BAL) samples: promising diagnostic modality in patients with smear-negative pulmonary tuberculosis

Purpose

The aim of the study is to assess the diagnostic utility of bronchoalveolar lavage (BAL) samples with GeneXpert test in diagnosis of TB in smear-negative patients.

Method

One-hundred sixty-nine cases were included in this study, as they had a radiological finding suggested to have pulmonary tuberculosis, while the sputum direct smear examination for acid-fast bacilli was negative. All cases prepared to do fiber-optic bronchoscope with bronchoalveolar lavage collection after their consent and post bronchoscope sputum collection for further molecular and microbiological examination.

Results

The combined diagnostic yield of all bronchoscopy procedures was 15.97% (27 cases of 169) and the final diagnosis of TB cases was established in 16 cases of 169 (9.4%) using BAL culture and in 20 cases of 169 (11.83%) by GeneXpert methods. Post bronchoscope direct sputum examination, culture, and GeneXpert evaluation gave diagnostic yield about 1.1%, 5.5%, and 7.1%, respectively. The specificity of GeneXpert examination of BAL and post bronchoscope sputum was 95.42% and 97.38%, respectively.

Conclusion

Early detection of pulmonary tuberculosis using fiber-optic bronchoscope BAL examination and post bronchoscope sputum with GeneXpert method promotes the accurate decision to start antituberculous therapy in patients with smear negative.

A geospatial platform to support visualization, analysis, and prediction of tuberculosis notification in space and time

Background

Tuberculosis has caused significant public health and economic burdens in Vietnam over the years. The Vietnam National Tuberculosis Program is facing considerable challenges in its goal to eliminate tuberculosis by 2030, with the COVID-19 pandemic having negatively impacted routine tuberculosis services at all administrative levels. While the turnaround time of tuberculosis infection may delay disease detection, high transportation frequency could potentially mislead epidemiological studies. This study was conducted to develop an online geospatial platform to support healthcare workers in performing data visualization and promoting the active case surveillance in community as well as predicting the TB incidence in space and time.

Method

This geospatial platform was developed using tuberculosis notification data managed by The Vietnam National Tuberculosis Program. The platform allows case distribution to be visualized by administrative level and time. Users can retrieve epidemiological measurements from the platform, which are calculated and visualized both temporally and spatially. The prediction model was developed to predict the TB incidence in space and time.

Results

An online geospatial platform was developed, which presented the prediction model providing estimates of case detection. There were 400,370 TB cases with bacterial evidence to be included in the study. We estimated that the prevalence of TB in Vietnam was at 414.67 cases per 100.000 population. Ha Noi, Da Nang, and Ho Chi Minh City were predicted as three likely epidemiological hotspots in the near future.

Conclusion

Our findings indicate that increased efforts should be undertaken to control tuberculosis transmission in these hotspots.

Whole-genome comparative analysis at the lineage/sublineage level discloses relationships between Mycobacterium tuberculosis genotype and clinical phenotype

Background

Human tuberculosis (TB) caused by members of the Mycobacterium tuberculosis complex (MTBC) is the main cause of death among infectious diseases worldwide. Pulmonary TB (PTB) is the most common clinical phenotype of the disease, but some patients develop an extrapulmonary (EPTB) phenotype in which any organ or tissue can be affected. MTBC species include nine phylogenetic lineages, with some appearing globally and others being geographically restricted. EPTB can or not have pulmonary involvement, challenging its diagnosis when lungs are not implicated, thus causing an inadequate treatment. Finding evidence of a specific M. tuberculosis genetic background associated with EPTB is epidemiologically relevant due to the virulent and multidrug-resistant strains isolated from such cases. Until now, the studies conducted to establish associations between M. tuberculosis lineages and PTB/EPTB phenotypes have shown inconsistent results, which are attributed to the strain predominance from specific M. tuberculosis lineages/sublineages in the samples analyzed and the use of low-resolution phylogenetic tools that have impaired sublineage discrimination abilities. The present work elucidates the relationships between the MTBC strain lineages/sublineages and the clinical phenotypes of the disease as well as the antibiotic resistance of the strains.

Methods

To avoid biases, we retrieved the raw genomic reads (RGRs) of all (n = 245) the M. tuberculosis strains worldwide causing EPTB available in databases and an equally representative sample of the RGRs (n = 245) of PTB strains. A multiple alignment was constructed, and a robust maximum likelihood phylogeny based on single-nucleotide polymorphisms was generated, allowing effective strain lineage/sublineage assignment.

Results

A significant Odds Ratio (OR range: 1.8–8.1) association was found between EPTB and the 1.1.1, 1.2.1, 4.1.2.1 and ancestral Beijing sublineages. Additionally, a significant association between PTB with 4.3.1, 4.3.3, and 4.5 and Asian African 2 and Europe/Russia B0/W148 modern Beijing sublineages was found. We also observed a significant association of Lineage 3 strains with multidrug resistance (OR 3.8; 95% CI [1.1–13.6]), as well as between modern Beijing sublineages and antibiotic resistance (OR 4.3; 3.8–8.6). In this work, it was found that intralineage diversity can drive differences in the immune response that triggers the PTB/EPTB phenotype.

Transmission of tuberculosis between foreign-born and Finnish-born populations in Finland, 2014-2017

We describe the epidemiology of tuberculosis (TB) and characterized Mycobacterium tuberculosis (M. tuberculosis) isolates to evaluate transmission between foreign-born and Finnish-born populations. Data on TB cases were obtained from the National Infectious Disease Register and denominator data on legal residents and their country of birth from the Population Information System. M. tuberculosis isolates were genotyped by spoligotyping and Mycobacterial Interspersed Repetitive Unit Variable Number Tandem Repeat (MIRU-VNTR). We characterized clusters by age, sex, origin and region of living which included both foreign-born cases and those born in Finland. During 2014-2017, 1015 TB cases were notified; 814 were confirmed by culture. The proportion of foreign-born cases increased from 33.3% to 39.0%. Foreign-born TB cases were younger (median age, 28 vs. 75 years), and had extrapulmonary TB or multidrug-TB more often than Finnish-born cases (P<0.01 for all comparisons). Foreign-born cases were born in 60 different countries; most commonly in Somalia (25.5%). Altogether 795 isolates were genotyped; 31.2% belonged to 80 different clusters (range, 2-13 cases/cluster). Fourteen (17.5%) clusters included isolates from both Finnish-born and foreign-born cases. An epidemiological link between cases was identified by (epidemiological) background information in two clusters. Although the proportion of foreign-born TB cases was considerable, our data suggests that transmission of TB between foreign and Finnish born population is uncommon.

Tuberculosis incidence among migrants according to migrant status: a cohort study, Denmark, 1993 to 2015

Background

Migrants account for the majority of tuberculosis (TB) cases in low-incidence countries in western Europe. TB incidence among migrants might be influenced by patterns of migration, but this is not well understood.

Aim

To investigate differences in TB risk across migrant groups according to migrant status and region of origin.

Methods

This prospective cohort study included migrants ≥ 18 years of age who obtained residency in Denmark between 1 January 1993 and 31 December 2015, matched 1:6 to Danish-born individuals. Migrants were grouped according to legal status of residency and region of origin. Incidence rates (IR) and incidence rate ratios (IRR) were estimated by Poisson regression.

Results

The cohort included 142,314 migrants. Migrants had significantly higher TB incidence (IR: 120/100,000 person-years (PY); 95% confidence interval (CI): 115–126) than Danish-born individuals (IR: 4/100,000 PY; 95% CI: 3–4). The IRR was significantly higher in all migrant groups compared with Danish-born (p < 0.01). A particularly higher risk was seen among family-reunified to refugees (IRR: 61.8; 95% CI: 52.7–72.4), quota refugees (IRR: 46.0; 95% CI: 36.6–57.6) and former asylum seekers (IRR: 45.3; 95% CI: 40.2–51.1), whereas lower risk was seen among family-reunified to Danish/Nordic citizens (IRR 15.8; 95% CI: 13.6–18.4) and family-reunified to immigrants (IRR: 16.9; 95% CI: 13.5–21.3).

Discussion

All migrants had higher TB risk compared with the Danish-born population. While screening programmes focus mostly on asylum seekers, other migrant groups with high risk of TB are missed. Awareness of TB risk in all high-risk groups should be strengthened and screening programmes should be optimised.

Extrapulmonary Tuberculosis in Denmark From 2009 to 2014; Characteristics and Predictors for Treatment Outcome

BACKGROUND

Extrapulmonary tuberculosis (EPTB) represents an increasing percentage of tuberculosis (TB) cases in Europe. However, strategies on TB prevention and successful treatment outcomes primarily target pulmonary TB. In this nationwide study, we present characteristics of EPTB, treatment outcomes, and predictors for unfavorable treatment outcomes.

METHODS

All patients diagnosed with EPTB from 2009 to 2014 were included. Logistic regression analyses were used to identify risk factors for unfavorable outcome. The following definitions were used: unfavorable outcome: the sum of treatment failed, lost to follow-up, and not evaluated; patient delay: time from TB-related symptom onset until first hospital contact related to TB; doctor delay: time from first TB-related contact in the health care system to start of TB treatment.

RESULTS

A total of 450 EPTB cases were notified, which represented 21.1% of all TB cases in Denmark. Immigrants accounted for 82.9%. Lymph nodes were the most common site of EPTB (55.4%) followed by pleural TB (13.4%). Patient delay was significantly longer among immigrants than Danes (60 vs 30 days; P < .01), whereas doctor delay was significantly longer among Danes (38.5 vs 28 days; P < .01). Treatment completion rates were high and reached 90.9% in 2014. Male gender (odds ratio [OR], 5.18; 95% confidence interval [CI], 1.79-15.04) and age 0-24 years (OR, 16.39; 95% CI, 2.02-132.64) were significantly associated with unfavorable outcome.

CONCLUSIONS

EPTB represented a significant number of all TB cases and was predominantly seen among younger immigrants in Denmark. To maintain high treatment completion rates, increased focus on male gender and young age is needed.

Impact of Mycobacterium tuberculosis complex lineages as a determinant of disease phenotypes from an immigrant rich moderate tuberculosis burden country

Background

Growing evidences suggested that the Mycobacterium tuberculosis complex (MTBC) lineages can determine the clinical outcome of pulmonary and extra-pulmonary tuberculosis. However, limited data only available revealing such association of bacterial genotypes and clinical phenotypes from immigrant rich countries.

Methods

A multicenter study has been carried out on a collection of 2092 (1003 extrapulmonary and 1089 pulmonary) MTBC isolates. Genotyping of all the isolates were carried out by spoligotyping and 24 loci based MIRU-VNTR typing.

Results

Demographically domination of young Saudi nationals (61.4%) and men (61.2%) were found in this cohort. Lymph nodes (62.4%) and gastrointestinal sites (16.7%) were the most common anatomical sites of infection. The predominant lineages were Delhi/CAS (26.9%), EAI (14.2%) and Ghana (9.9%). Mycobacterium africanum type I and II were reported for the first time in the country among extrapulmonary cases. ‘Ancestral’ lineages M.bovis (OR-5.22; 95% CI-2.23-8.22, p- < 0.001) and Delhi/CAS (OR-0.57; 95% CI-0.411-0.734, p- < 0.001) were directly associated with lymph node tuberculosis and gastrointestinal tuberculosis (M. bovis-OR-0.33; 95% CI-0.085-0.567, p-0.001 and Delhi/CAS-OR-1.87; 95% CI-1.22-2.53, p- < 0.001) respectively. Among the ‘Modern’ lineages, EAI showed significant association to central nervous system tuberculosis (OR-1.98; 95% CI-0.76-3.19, p-0.04) and Uganda-I to gastrointestinal tuberculosis (OR-2.41; 95% CI-0.77-4.06, p-0.02).

Conclusions

The findings substantially contribute to the emerging evidences that MTBC lineages influence disease phenotypes and epidemiological consequences.

Electronic supplementary material

The online version of this article (10.1186/s12931-018-0966-x) contains supplementary material, which is available to authorized users.

Predictors for treatment outcomes among patients with drug-susceptible tuberculosis in the Netherlands: a retrospective cohort study

OBJECTIVES

We evaluated treatment outcomes and predictors for poor treatment outcomes for tuberculosis (TB) among native- and foreign-born patients with drug-susceptible TB (DSTB) in the Netherlands.

METHODS

This retrospective cohort study included adult patients with DSTB treated from 2005 to 2015 from a nationwide exhaustive registry. Predictors for unsuccessful treatment outcomes (default and failure) and TB-associated mortality were analysed using multivariate logistic regression.

RESULTS

Among 5674 identified cases, the cumulative incidence of unsuccessful treatment and mortality were 2.6% (n/N = 146/5674) and 2.0% (112/5674), respectively. Although most patients were foreign-born (71%; 4042/5674), no significant differences in these outcomes were observed between native- and foreign-born patients (p > 0.05). Significant predictors for unsuccessful treatment were aged 18-24 years (odds ratio (OR), 2.04; 95% CI 1.34-3.10), homelessness (OR, 2.56; 95% CI 1.16-5.63), prisoner status (OR, 5.39; 95% CI 2.90-10.05) and diabetes (OR, 2.02; 95% CI 1.03-3.97). Furthermore, predictors for mortality were aged 74-84 years (OR, 5.58; 95% CI 3.10-10.03) or ≥85 years (OR, 9.35, 95% CI 4.31-20.30), combined pulmonary and extra-pulmonary TB (OR, 4.97; 95% CI 1.42-17.41), central nervous system (OR, 120, 95% CI 34.43-418.54) or miliary TB (OR, 10.73, 95% CI 2.50-46.02), drug addiction (OR, 3.56; 95% CI 1.34-9.47) and renal insufficiency/dialysis (OR, 3.23; 95% CI 1.17-8.96).

CONCLUSIONS

Native- and foreign-born patients exhibited similar TB treatment outcomes. To further reduce disease transmission and inhibit drug resistance, special attention should be given to high-risk patients.

Trends and differences in tuberculosis incidences and clustering among natives in Denmark, Sweden and Finland: comparison of native incidences and molecular epidemiology among three low-incidence countries

OBJECTIVES

To compare the epidemiology of tuberculosis (TB) in Denmark, Sweden and Finland, by focusing on the native population in order to identify epidemiologic differences and thus indirectly possible differences in TB control.

METHODS

TB incidence trends from 1990 through 2015 were compared among the countries. In addition, for the periods 2012-2013 and 2014-2015, genotyping data were compared. Genotyping was performed using the 24-locus mycobacterial interspersed repetitive unit-variable number of tandem repeat (MIRU-VNTR) method in Denmark and Sweden. For Finland, spoligotyping in conjunction with the 15-locus MIRU-VNTR method was used for 2012-2013 and translated into the 24-locus MIRU-VNTR when feasible, and for 2014-2015 only MIRU-VNTR was used. Both incidence trends and molecular epidemiology were assessed for native cases.

RESULTS

The average annual rate of change in TB incidence for native Danes was -2.4% vs. -6.1% and -6.9% for native Swedes and Finns respectively. In 2012-2013 Denmark had 52 native cases in the largest transmission chain vs. three cases in Sweden and ten in Finland, and during the same period the clustering rate for native Danes was 48.8% vs. 6.5% and 18.2% for native Swedes and Finns respectively. For 2014-2015, a similar pattern was seen.

CONCLUSIONS

The decline of TB among natives in Denmark is slower than for Sweden and Finland, and it seems Denmark has more active transmission among natives. The focused assessment on basic native TB epidemiology reveals striking differences in TB transmission among otherwise similar low-TB-incidence countries.

Mycobacterium tuberculosis genotypes and predominant clones among the multidrug-resistant isolates in Spain 1998-2005

Although the incidence of tuberculosis (TB) is gradually decreasing in Spain, there is an increase in the proportion of foreign-born cases. This changing scenario is slowly shifting the local TB epidemiology from endemic to imported cases with an increased risk for multidrug-resistant (MDR) and extensively drug resistant (XDR) strains of Mycobacterium tuberculosis complex. MDR/XDR strains from Spain (n=366 MTBC isolates, 1 strain per patient) isolated between 1998 and 2005 were retained for this retrospective analysis. All strains were analyzed by spoligotyping, while 12-loci MIRU-VNTR data were available for 106 isolates from 2003 to 2005. Demographic, phylogenetic, and epidemiologic analyses using anonymized data were collected and analyzed using the SITVIT2 database. Our study provides with a first snapshot of genetic diversity of MDR/XDR-TB in several autonomous regions of Spain. It highlights significantly more of SIT1/Beijing and SIT66/BOV MDR isolates (5.7% and 7.38% respectively) and increasingly more foreign-born cases from Eastern Europe. Future studies should focus on shared genotypes between Spanish and foreign-born patients to decipher the modes of transmission and risk factors involved, and decipher the proportion of imported cases of active disease versus cases of reactivation of latent TB infection among foreign-born individuals.

Clinical Features and Outcome in Adult Cases of Tuberculous Meningitis in Tertiary Care Hospital in Antananarivo, Madagascar

Purpose. We aimed to describe and to assess prognosis factors in tuberculous meningitis in adult patients. Methods. We performed a retrospective study of case records of adult patients. Patients classified as definite, probable, or possible tuberculous meningitis according to standardized definition criteria were included and assessed in the study. Results. Seventy-five patients were included in the study. Tuberculous meningitis was classified as definite in 8 (10.7%), probable in 44 (58.7%), and possible in 23 patients (30.6%). HIV was found in 3% of patients. Patients were in advanced stages at admission in 82.7%. Median duration of symptoms prior to admission was 3 weeks (IQR: 2–5). Median time to diagnosis following admission was 5 days (IQR: 3–8). Median CSF WCC was 75 per mm³ with lymphocytic predominance in 38 cases (52.8%). Median CSF glucose level was 1.48 mmol/L and median CSF protein level was 1 g/L. Mortality rate was 28%. Age ≥ 35 years (aOR: 4.06; 95% CI: 1.16–14.26) and coma (aOR: 12.98; 95% CI: 1.13–149.16) predicted inpatient mortality. Conclusion. Most of the patients experienced more than 3 weeks of diagnostic delay prior to admission. Mortality was high and occurred early after admission. Age and coma were identified as independent prognosis factors.

Clinical Presentation, Diagnosis, and Bacterial Epidemiology of Peritoneal Tuberculosis in Two University Hospitals in France

Introduction

Diagnosis of peritoneal tuberculosis (pTB) is difficult, even in developed countries, where data are lacking. The aim of the present study was to describe the clinical presentation, diagnosis, and bacterial epidemiology of pTB in France over a 10-year period.

Methods

A retrospective study was conducted on pTB in two university hospitals in France, between January 2004 and December 2014.

Results

Among the 34 patients, 76.5% were migrants from areas of endemic tuberculosis (TB), mainly Africa. The main presentation (85.3%) was a checkup of ascites or suspicion of peritoneal carcinomatosis. On abdominal computed tomography, ascites was found in 90.6% and peritoneal thickening in 75%. Surgery was required for diagnosis in 58.8% of patients. Six of the patients who did not undergo surgery had ultrasound-guided peritoneal biopsy. Bacteriology was positive for ascites in only 58.1% of cases, for peritoneal biopsy in 73.3%, while granuloma was found in 95.5%. TB polymerase chain reaction (PCR) was positive in 25% of peritoneal biopsy. Mycobacterium bovis was isolated in 23.1% of cases and Mycobacterium tuberculosis in 76.9%. Isolates were fully susceptible (except M. bovis naturally resistant to pyrazinamide). Many (38%) belonged to the lineage T (genetic analysis by spoligotyping). Cure rate was high (76.5%), after a 6–9 months of anti-tuberculous therapy.

Conclusion

In developed countries, early diagnosis of pTB is still a challenge. Ultrasound-guided peritoneal biopsy may facilitate diagnosis. TB PCR can be useful on peritoneal biopsy. The lineage T was the most prevalent lineage, but more data are required to directly incriminate this lineage in the pathophysiology of pTB.

Genotype heterogeneity of Mycobacterium tuberculosis within geospatial hotspots suggests foci of imported infection in Sydney, Australia

In recent years the State of New South Wales (NSW), Australia, has maintained a low tuberculosis incidence rate with little evidence of local transmission. Nearly 90% of notified tuberculosis cases occurred in people born in tuberculosis-endemic countries. We analyzed geographic, epidemiological and genotypic data of all culture-confirmed tuberculosis cases to identify the bacterial and demographic determinants of tuberculosis hotspot areas in NSW. Standard 24-loci mycobacterium interspersed repetitive unit-variable number tandem repeat (MIRU-24) typing was performed on all isolates recovered between 2009 and 2013. In total 1692/1841 (91.9%) cases with confirmed Mycobacterium tuberculosis infection had complete MIRU-24 and demographic data and were included in the study. Despite some year-to-year variability, spatio-temporal analysis identified four tuberculosis hotspots. The incidence rate and the relative risk of tuberculosis in these hotspots were 2- to 10-fold and 4- to 8-fold higher than the state average, respectively. MIRU-24 profiles of M. tuberculosis isolates associated with these hotspots revealed high levels of heterogeneity. This suggests that these spatio-temporal hotspots, within this low incidence setting, can represent areas of predominantly imported infection rather than clusters of cases due to local transmission. These findings provide important epidemiological insight and demonstrate the value of combining tuberculosis genotyping and spatiotemporal data to guide better-targeted public health interventions.

Tuberculosis in immigrants in Finland, 1995-2013

Increasing immigration from high tuberculosis (TB) incidence countries is a challenge for surveillance and control in Finland. Here, we describe the epidemiology of TB in immigrants by using national surveillance data. During 1995-2013, 7030 (84·7%) native and 1199 (14·4%) immigrant cases were identified. The proportion of immigrant cases increased from 5·8% in 1995 to 32·1% in 2013, consistent with increasing immigrant population (2·1-5·6%) and decreasing incidence of TB in the native population (from 12·1 to 3·5/100 000). TB cases in immigrants were significantly younger, more often female, and had extrapulmonary TB more often than native cases (P < 0·01 for all comparisons); multidrug resistance was also more common in immigrants than natives (P < 0·01). Immigrant cases were born in 82 different countries; most commonly in Somalia and the former Soviet Union/Russia. During 2008-2013, 433 Mycobacterium tuberculosis isolates from immigrants were submitted for spoligotyping; 10 different clades were identified. Clades were similar to those found in the case's country of birth. Screening immigrants from high-incidence countries and raising awareness of common characteristics and symptoms of TB is important to ensure early diagnosis and to prevent transmission.

Can Australia eliminate TB? Modelling immigration strategies for reaching MDG targets in a low-transmission setting

BACKGROUND

The 2050 Millennium Development Goals (MDG) for tuberculosis (TB) aim for elimination of TB as a public health issue. We used a mathematical modelling approach to evaluate the feasibility of this target in a low-prevalence setting with immigration-related strategies directed at latent tuberculosis.

METHODS

We used a stochastic individual-based model to simulate tuberculosis disease among immigrants to Victoria, Australia; a representative low-transmission setting. A variety of screening and treatment approaches aimed at preventing reactivation of latent infection were applied to evaluate overall tuberculosis incidence reduction and rates of multidrug resistant disease.

RESULTS

Without additional intervention, tuberculosis incidence was predicted to reach 34.5 cases/million by 2050. Strategies involving the introduction of an available screening/treatment combination reduced TB incidence to between 16.9-23.8 cases/million, and required screening of 136-427 new arrivals for each case of TB prevented. Limiting screening to higher incidence regions of origin was less effective but more efficient.

CONCLUSIONS

Public health strategies targeting latent tuberculosis infection in immigrants may substantially reduce tuberculosis incidence in a low prevalence region. However, immigration-focused strategies cannot achieve the 2050 MDG and alternative or complementary approaches are required.

Tuberculosis among migrant populations in the European Union and the European Economic Area

Background: Although tuberculosis (TB) incidence has been decreasing in the European Union/European Economic Area (EU/EEA) in the last decades, specific subgroups of the population, such as migrants, remain at high risk of TB. This study is based on the report ‘Key Infectious Diseases in Migrant Populations in the EU/EEA’ commissioned by The European Centre for Disease Prevention and Control. Methods: We collected, critically appraised and summarized the available evidence on the TB burden in migrants in the EU/EEA. Data were collected through: (i) a comprehensive literature review; (ii) analysis of data from The European Surveillance System (TESSy) and (iii) evidence provided by TB experts during an infectious disease workshop in 2012. Results: In 2010, of the 73 996 TB cases notified in the EU/EEA, 25% were of foreign origin. The overall decrease of TB cases observed in recent years has not been reflected in migrant populations. Foreign-born people with TB exhibit different socioeconomic and clinical characteristics than native sufferers. Conclusion: This is one of the first studies to use multiple data sources, including the largest available European database on infectious disease notifications, to assess the burden and provide a comprehensive description and analysis of specific TB features in migrants in the EU/EEA. Strengthened information about health determinants and factors for migrants’ vulnerability is needed to plan, implement and evaluate targeted TB care and control interventions for migrants in the EU/EEA.

Influence of migration on tuberculosis in a semi-urban area

AIMS

To describe the epidemiology of tuberculosis and analyzing the differences among native and immigrant patients in Area III of the Region of Murcia.

METHODS

Cohort study of tuberculosis cases reported to the Epidemiological Surveillance Service from 2004 to 2009. Data collection was performed through the System of Notification Diseases, reviewing clinical files and epidemiological surveys.

RESULTS

One hundred sixty two cases were detected; 110 (67.9%) were immigrants, whose incidence rates ranged from 43.4 to 101.2 cases per 100,000 inhabitants. Ecuador (42.7%), Bolivia (30%) and Morocco (18.2%) were the main nationalities. Immigrants were younger than Spanish population (P<.001). The overall diagnostic delay was 50.5 days: 59.5 in Spanish and 47 in foreigners. Moroccans had higher proportions of extrapulmonary TB (P=.02). Mainly, immigrant population took treatment with four drugs (P<.001). Natives had better treatment adherence (P=.04). Spanish cases tuberculosis were associated with smoking (P<.001), the same as alcohol consumption (P=.01) and injection drug use (P<.001), nevertheless in the foreign-born population the most relevant risk factor was overcrowding (P<.001).

CONCLUSIONS

The incidence tuberculosis rates are higher among immigrant population, whose the main risk factor is overcrowding. In contrast, Spanish cases are associated with toxic substances consumption and increasing age.

Molecular epidemiology of tuberculosis in Finland, 2008-2011

In industrialized countries the majority of tuberculosis (TB) cases are linked to immigration. In Finland, most cases are still Finnish born but the number of foreign born cases is steadily increasing. In this 4-year population based study, the TB situation in Finland was characterized by a genotypic analysis of Mycobacterium tuberculosis isolates. A total of 1048 M. tuberculosis isolates (representing 99.4% of all culture positive cases) were analyzed by spoligotyping and MIRU. Spoligotype lineages belonging to the Euro-American family were predominant among the Finnish isolates, particularly T (n=346, 33.0%) and Haarlem (n=237, 22.6%) strains. The lineage signature was unknown for 130 (12.4%) isolates. Out of the 17 multi-drug resistant TB strains, 10 (58.8%) belonged to the Beijing lineage. In total, 23 new SIT designations were given and 51 orphan strains were found, of which 58 patterns were unique to Finland. Phylogeographical TB mapping as compared to neighboring countries showed that the population structure in Finland most closely resembled that observed in Sweden. By combining spoligotyping and MIRU results, 98 clusters comprising 355 isolates (33.9%) were found. Only 10 clusters contained both Finnish and foreign born cases. In conclusion, a large proportion of the M. tuberculosis isolates were from Finnish born elderly patients. Moreover, many previously unidentified spoligotype profiles and isolates belonging to unknown lineages were encountered.

Draft Genome Sequence of a Clinical Isolate of Multidrug-Resistant Mycobacterium tuberculosis East African Indian Strain OSDD271

We describe the genome sequencing and analysis of a clinical isolate of Mycobacterium tuberculosis East African Indian (EAI) strain OSDD271 from India.

Genetic diversity of Mycobacterium tuberculosis in Peru and exploration of phylogenetic associations with drug resistance

Background

There is limited available data on the strain diversity of M tuberculosis in Peru, though there may be interesting lessons to learn from a setting where multidrug resistant TB has emerged as a major problem despite an apparently well-functioning DOTS control programme.

Methods

Spoligotyping was undertaken on 794 strains of M tuberculosis collected between 1999 and 2005 from 553 community-based patients and 241 hospital-based HIV co-infected patients with pulmonary tuberculosis in Lima, Peru. Phylogenetic and epidemiologic analyses permitted identification of clusters and exploration of spoligotype associations with drug resistance.

Results

Mean patient age was 31.9 years, 63% were male and 30.4% were known to be HIV+. Rifampicin mono-resistance, isoniazid mono-resistance and multidrug resistance (MDR) were identified in 4.7%, 8.7% and 17.3% of strains respectively. Of 794 strains from 794 patients there were 149 different spoligotypes. Of these there were 27 strains (3.4%) with novel, unique orphan spoligotypes. 498 strains (62.7%) were clustered in the nine most common spoligotypes: 16.4% SIT 50 (clade H3), 12.3% SIT 53 (clade T1), 8.3% SIT 33 (LAM3), 7.4% SIT 42 (LAM9), 5.5% SIT 1 (Beijing), 3.9% SIT 47 (H1), 3.0% SIT 222 (clade unknown), 3.0% SIT1355 (LAM), and 2.8% SIT 92 (X3). Amongst HIV-negative community-based TB patients no associations were seen between drug resistance and specific spoligotypes; in contrast HIV-associated MDRTB, but not isoniazid or rifampicin mono-resistance, was associated with SIT42 and SIT53 strains.

Conclusion

Two spoligotypes were associated with MDR particularly amongst patients with HIV. The MDR-HIV association was significantly reduced after controlling for SIT42 and SIT53 status; residual confounding may explain the remaining apparent association. These data are suggestive of a prolonged, clonal, hospital-based outbreak of MDR disease amongst HIV patients but do not support a hypothesis of strain-specific propensity for the acquisition of resistance-conferring mutations.

The re-emergence of tuberculosis: what have we learnt from molecular epidemiology?

Tuberculosis (TB) has re-emerged over the past two decades: in industrialized countries in association with immigration, and in Africa owing to the human immunodeficiency virus epidemic. Drug-resistant TB is a major threat worldwide. The variable and uncertain impact of TB control necessitates not only better tools (diagnostics, drugs, and vaccines), but also better insights into the natural history and epidemiology of TB. Molecular epidemiological studies over the last two decades have contributed to such insights by answering long-standing questions, such as the proportion of cases attributable to recent transmission, risk factors for recent transmission, the occurrence of multiple Mycobacterium tuberculosis infection, and the proportion of recurrent TB cases attributable to re-infection. M. tuberculosis lineages have been identified and shown to be associated with geographical origin. The Beijing genotype is strongly associated with multidrug resistance, and may have escaped from bacille Calmette-Guérin-induced immunity. DNA fingerprinting has quantified the importance of institutional transmission and laboratory cross-contamination, and has helped to focus contact investigations. Questions to be answered in the near future with whole genome sequencing include identification of chains of transmission within clusters of patients, more precise quantification of mixed infection, and transmission probabilities and rates of progression from infection to disease of various M. tuberculosis lineages, as well as possible variations in vaccine efficacy by lineage. Perhaps most importantly, dynamics in the population structure of M. tuberculosis in response to control measures in high-prevalence areas should be better understood.

Epidemiological analyses of tuberculosis in Archangelsk, Russia and implementation of a rapid assay for detection of resistance in this high burden setting

BACKGROUND

Tuberculosis (TB) is a major problem in Russia, particularly regarding multidrug-resistant tuberculosis (MDR-TB). Rapid drug susceptibility testing methods are therefore needed.

OBJECTIVES

To perform epidemiological analyses of TB in the Archangelsk region and to evaluate the molecular method GenoType®MTBDRplus in this type of setting.

MATERIALS AND METHODS

Clinical and microbiological data of all TB patients in Archangelsk were collected in 2010. Smear-positive sputa were analysed by MTBDRplus and Bactec MGIT 960.

RESULTS

The number of TB cases was 812 (incidence 65/105) and among these patients, 151 cases were registered in the penitentiary system (incidence 1162/105). Most patients were men, 94% had pulmonary TB and 22% were relapses. Out of all cases, 341 (42%) were smear positive and thus contagious and 176 (22%) had MDR-TB, among which one had extensively drug resistant tuberculosis (XDR-TB). Furthermore, two TB patients had strains being resistant to rifampicin, but susceptible to isoniazid. The number of cases being both contagious and MDR-TB was 128 representing 15.8% of all TB cases (incidence 10.2/105). Among these 128 TB patients 37 were relapses representing 25.7% of all the relapse cases. The results of MTBDRplus and Bactec MGIT analyses corresponded in 98.8%.

CONCLUSIONS

In Archangelsk many TB patients had contagious MDR-TB thus being hazardous in society and relapsing pulmonary TB was common. The TB situation in the prisons was particularly severe. The analyses showed furthermore that MTBDRplus is of major value in this setting.

Tuberculosis among Africans living in the United States, 2000-2009

The incidence of tuberculosis (TB) has declined steadily in the United States; however, foreign-born persons are disproportionately affected. The aim of our study was to describe characteristics of TB patients diagnosed in the United States who originated from the African continent. Using data from the U.S. National Tuberculosis Surveillance System, we calculated TB case rates and analyzed differences between foreign-born patients from Africa compared with other foreign-born and U.S.-born patients. The 2009 TB case rate among Africans (48.1/100,000) was 3 times as high as among other foreign-born and 27 times as high as among U.S.-born patients. Africans living in the United States have high rates of TB disease; they are more likely to be HIV-positive and to have extrapulmonary TB. Identification and treatment of latent TB infection, HIV testing and treatment, and a high index of suspicion for extrapulmonary TB are needed to better address TB in this population.

Current trends of Mycobacterium tuberculosis molecular epidemiology in Saudi Arabia and associated demographical factors

Data are scarce on demographical factors related to the population structure of Mycobacterium tuberculosis in Saudi Arabia. A study was conducted on 902 clinical isolates to explore current trends in the phylogeography and associated demographical factors of tuberculosis by using spoligotyping and 24 loci based MIRU-VNTR typing. Young male patients (aged 16-29 and 30-44) were predominant in this cohort. The phylogenetic diversity among M. tuberculosis isolates was found high, as almost all known genetic lineages were identified. Delhi/CAS (26.4%), EAI (13.7%) and Haarlem (11.3%) were the most common lineages observed, particularly among the low age groups (16-29 and 30-44 years), whereas elderly patients (>60 years) showed a predominance in the lineages S, Ghana, TUR and Uganda-I. A statistically significant association was observed between gender of the patients and lineages of EAI (p value 0.026) and LAM (p value 0.005). Overall, molecular strain cluster rate was 34.4% with an elevated rate among patients aged below 15 years (43.1%), while cases among the elderly (>60 years) showed the lowest degree of clustering (12.5%). The largest level of clustering was noticed among cases caused by strains of the lineages Haarlem (59.8%), Beijing (55.8%) and LAM (42.8%). The current population structure of M. tuberculosis in Saudi Arabia is highly diverse with significant associations to demography, transmission dynamics and origin of the patients. The difference in genotype distributions among low and high aged patients reflects the ongoing change in the strain population structure in the country.

First insights into the phylogenetic diversity of Mycobacterium tuberculosis in Nepal

Background

Tuberculosis (TB) is a major public health problem in Nepal. Strain variation in Mycobacterium tuberculosis may influence the outcome of TB infection and disease. To date, the phylogenetic diversity of M. tuberculosis in Nepal is unknown.

Methods and Findings

We analyzed 261 M. tuberculosis isolates recovered from pulmonary TB patients recruited between August 2009 and August 2010 in Nepal. M. tuberculosis lineages were determined by single nucleotide polymorphisms (SNP) typing and spoligotyping. Drug resistance was determined by sequencing the hot spot regions of the relevant target genes. Overall, 164 (62.8%) TB patients were new, and 97 (37.2%) were previously treated. Any drug resistance was detected in 50 (19.2%) isolates, and 16 (6.1%) were multidrug-resistant. The most frequent M. tuberculosis lineage was Lineage 3 (CAS/Delhi) with 106 isolates (40.6%), followed by Lineage 2 (East-Asian lineage, includes Beijing genotype) with 84 isolates (32.2%), Lineage 4 (Euro-American lineage) with 41 (15.7%) isolates, and Lineage 1 (Indo-Oceanic lineage) with 30 isolates (11.5%). Based on spoligotyping, we found 45 different spoligotyping patterns that were previously described. The Beijing (83 isolates, 31.8%) and CAS spoligotype (52, 19.9%) were the dominant spoligotypes. A total of 36 (13.8%) isolates could not be assigned to any known spoligotyping pattern. Lineage 2 was associated with female sex (adjusted odds ratio [aOR] 2.58, 95% confidence interval [95% CI] 1.42–4.67, p = 0.002), and any drug resistance (aOR 2.79; 95% CI 1.43–5.45; p = 0.002). We found no evidence for an association of Lineage 2 with age or BCG vaccination status.

Conclusions

We found a large genetic diversity of M. tuberculosis in Nepal with representation of all four major lineages. Lineages 3 and 2 were dominating. Lineage 2 was associated with clinical characteristics. This study fills an important gap on the map of the M. tuberculosis genetic diversity in the Asian region.

Mycobacterium tuberculosis strains potentially involved in the TB epidemic in Sweden a century ago

A hundred years ago the prevalence of tuberculosis (TB) in Sweden was one of the highest in the world. In this study we conducted a population-based search for distinct strains of Mycobacterium tuberculosis complex isolated from patients born in Sweden before 1945. Many of these isolates represent the M. tuberculosis complex population that fueled the TB epidemic in Sweden during the first half of the 20^th century.

Ethnicity and mycobacterial lineage as determinants of tuberculosis disease phenotype

BACKGROUND

Emerging evidence suggests that Mycobacterium tuberculosis (Mtb) lineage and host ethnicity can determine tuberculosis (TB) clinical disease patterns but their relative importance and interaction are unknown.

METHODS

We evaluated prospectively collected TB surveillance and Mtb strain typing data in an ethnically heterogeneous UK population. Lineage assignment was denoted using 15-loci mycobacterial interspersed repetitive units containing variable numbers of tandem repeats (MIRU-VNTR) and MIRU-VNTRplus. Geographical and ethnic associations of the six global Mtb lineages were identified and the influence of lineage and demographic factors on clinical phenotype were assessed using multivariate logistic regression.

RESULTS

Data were available for 1070 individuals with active TB which was pulmonary only, extrapulmonary only and concurrent pulmonary-extrapulmonary in 52.1%, 36.9% and 11.0% respectively. The most prevalent lineages were Euro-American (43.7%), East African Indian (30.2%), Indo-Oceanic (13.6%) and East Asian (12.2%) and were geo-ethnically restricted with, for example, Indian subcontinent ethnicity inversely associated with Euro-American lineage (OR 0.23; 95% CI 0.14 to 0.39) and positively associated with the East African-Indian lineage (OR 4.04; 95% CI 2.19 to 7.45). Disease phenotype was most strongly associated with ethnicity (OR for extrathoracic disease 21.14 (95% CI 6.08 to 73.48) for Indian subcontinent and 14.05 (3.97 to 49.65) for Afro-Caribbean), after adjusting for lineage. With East Asian lineage as the reference category, the Euro-American (OR 0.54; 95% CI 0.32 to 0.91) and East-African Indian (OR 0.50; 95% CI 0.29 to 0.86) lineages were negatively associated with extrathoracic disease, compared with pulmonary disease, after adjusting for ethnicity.

CONCLUSIONS

Ethnicity is a powerful determinant of clinical TB phenotype independently of mycobacterial lineage and the role of ethnicity-associated factors in pathogenesis warrants investigation.

Travel-related imported infections in Europe, EuroTravNet 2009

The aim of this study was to investigate travel-associated morbidity in European travellers in 2009 in comparison with 2008, with a particular emphasis on emerging infectious diseases with the potential for introduction into Europe. Diagnoses with demographic, clinical and travel-related predictors of disease from ill returning travelers presenting to 12 core EuroTravNet sites from January to December 2009 were analysed. A total of 6392 patients were seen at EuroTravNet core sites in 2009, as compared with 6957 in 2008. As compared with 2008, there was a marked increase in the number of travellers exposed in North America and western Europe. Respiratory illnesses, in particular pandemic A(H1N1) influenza, influenza-like syndromes, and tuberculosis, were also observed more frequently. A significant increase in reported dengue cases in 2009 as compared with 2008 was observed (n = 172, 2.7% vs. n = 131, 1.90%) (p 0.002). The numbers of malaria and chikungunya cases were also increasing, although not significantly. Two deaths were recorded: visceral leishmaniasis and sepsis in a Sudanese migrant, and Acinetobacter sp. pneumonia in a patient who had visited Spain. This is the most comprehensive study of travel-related illness in Europe in 2009 as compared with 2008. A significant increase in travel-related respiratory and vector-borne infections was observed, highlighting the potential risk for introduction of these diseases into Europe, where competent vectors are present. The number of traveller deaths is probably underestimated. The possible role of the travellers in the emergence of infectious diseases of public health concern is highlighted.

Tuberculosis as a risk factor for systemic lupus erythematosus: results of a nationwide study in Taiwan

A previous study, with relatively small number of patients, showed that prior Mycobacterium tuberculosis (TB) may precipitate SLE in patients from endemic areas. The purpose of the study was to investigate the relationship between prior TB infection and systemic lupus erythematosus (SLE) from the National Health Insurance Research Database (NHIRD) in Taiwan. Cases of SLE and TB were identified from the NHIRD with corresponding ICD-9 codes 710.0 and 011-018, respectively, from January 2000 to December 2008. A total of 2,721 cases of SLE and 10,823 control subjects were included in data analysis. The average annual incidence rate was 8.1 per 100,000. The annual incidence rates of SLE decreased from 6.38 per 100,000 to 2.55 per 100,000 during 2000-2008. Compared with the control subjects, SLE patients were more likely to be white collar workers (P = 0.0005), reside in highly urbanized areas (P = 0.0140), and have higher incomes (P = 0.0088). TB was much more prevalent in SLE patients than in the control subjects (1.8 vs. 0.9%, P < 0.001). The mean time interval between diagnosis of TB and SLE was 45.58 ± 39.0 months. On multivariate analysis, TB was the greatest potential risk factor for precipitating SLE (OR = 2.11, 95% CI = 1.49-3.00). In addition, patients with co-existing TB and DM had a higher risk of SLE than the control group (OR = 3.91, 95% CI 1.84-8.31). In conclusion, this study suggests that there is an increased risk of precipitating SLE among patients with TB in Taiwan from a nationwide health insurance research dataset. Mycobacterial infections could trigger autoimmune diseases in experimental studies. Furthermore, a study with relatively small number of patients revealed that prior TB may precipitate SLE in patients from endemic areas. There is an increased risk of precipitating SLE among patients with TB in Taiwan from a nationwide health insurance research dataset during a 9-year period.