Biomedical subjects

E Heldal

Publications and source records attributed to E Heldal.

At least 19 recordsLinked to original sources

PubMed2006

Tuberculosis screening in migrants in selected European countries shows wide disparities.

Well-established tuberculosis screening units in Western Europe were selectively sampled. Three screening units in Norway, two in the UK, one in the Netherlands and one in Switzerland were evaluated. The aim of this study was to describe a range of service models used at a number of individual tuberculosis units for the screening of new entrants into Europe. Semi-structured interviews were conducted with clinicians, nurses and administrators from a selected sample of European tuberculosis screening units. An outline of key themes to be addressed was forwarded to units ahead of scheduled interviews. Themes included the history of the unit, structure, processes and outputs involved in screening new entrants for tuberculosis. Considerable variation in screening services exists in the approaches studied. Units are sited in transit camps or as units within hospital facilities. Staff capacity and administration varies from one clinic per week with few dedicated staff to fully dedicated units. Only one site recorded symptoms; tuberculin testing was universal in children, but varied in adults; chest radiograph screening was universal except at one site where a positive tuberculin skin test or symptoms were required in those <35 yrs of age before ordering a radiograph. Few output data are routinely and systematically collected, which hinders comparison and determination of effectiveness and efficiency. Service models for screening new immigrants for tuberculosis appear to vary in Western Europe. The systematic collection of data would make international comparisons between units easier and help draw conclusions that might usefully inform service development.

Adult↗

PubMed2006

Tuberculosis control in conflict-affected East Timor, 1996-2004.

SETTING: East Timor has undergone major political changes in the past 10 years. Tuberculosis (TB) control has flourished, despite chronic low tension conflict, a brief but intense period of high-level conflict and post-conflict reconstruction. OBJECTIVE: To assess TB control in East Timor from 1996 to 2004. DESIGN: Data were collected from a variety of sources. Key TB programme indicators were analysed with reference to WHO targets to assess the performance of the three TB control programmes that operated during the study period. RESULTS: Before 1999, a non-governmental TB control programme was established in several districts in parallel with the government TB programme, and showed optimistic results. External donor funds, technical assistance and local control strategies were key components. In 1999, conflict led to complete disruption of both programmes. In 2000, a National Tuberculosis Control Programme (NTP) was established from the non-governmental programme in collaboration with other partners. The smear-positive TB case notification rate of 108 per 100000 population is the highest in the region and reflects high population coverage. The cure rate of 81% is close to reaching the WHO target. CONCLUSION: High-quality TB control has been introduced in conflict-affected East Timor. Further research is needed to examine Timorese approaches to inform other, similar settings.

Directly Observed Therapy↗

PubMed2005

Long-term risk of tuberculosis among immigrants in Norway.

BACKGROUND: Two-thirds of the tuberculosis (TB) cases in Norway were discovered among immigrants. Some cases were discovered at arrival, but many develop the disease several years post-migration. Knowledge about how long after migration to Norway TB were discovered will enable us to better target preventive measures including preventive therapy. This study examines the long-term risk of TB among immigrants in Norway. METHODS: All non-Nordic immigrants who arrived in Norway between 1986 and 2002, as registered by the Norwegian Directorate of Immigration, were followed-up. Their TB status was determined from the National Tuberculosis Registry. Observation period for TB cases was calculated from the date of arrival in Norway to TB registration. For persons without TB, it was calculated from the date of arrival in Norway to the date of emigration from Norway, date of death, or until end of follow-up (December 31, 2002). RESULTS: For immigrants from Africa and Asia, the TB rates were 190 and 80 per 100,000 person-years (PY), respectively, at 7 years post-migration. For immigrants from Somalia, Pakistan, Vietnam, and the former Yugoslavia, the rates were 520, 160, 210, and 40 per 100 000 PY respectively, at 7 years post-migration. These rates were 7 to 90 times higher than the crude TB incidence for Norway. This increased risk applies to both genders, pulmonary and extra-pulmonary sites. CONCLUSION: These results indicate the need for health personnel to be aware that immigrants remain at high risk of TB many years post-migration. Screening for TB on arrival should be strengthened, and preventive therapy for those with recent TB infection should be considered.

Adult↗

PubMed2005

Tuberculosis in contacts need not indicate disease transmission.

BACKGROUND: Traditional contact investigation is an important tool for controlling tuberculosis. It may also help to indicate drug susceptibility patterns when Mycobacterium tuberculosis cultures are not available. Such investigations often underestimate the degree of transmission found by genotyping, but overestimation may also occur. This report is the result of a routine successive DNA restriction fragment length polymorphism (RFLP) analysis of M tuberculosis isolated in Norway. METHOD: Fifteen immigrants belonging to the same community were notified with tuberculosis during February to September 2003. The mycobacterial isolates were analysed by RFLP. RESULTS: All 15 patients had social contact with each other and 13 belonged to the same church community. A total of 14 cultures were positive for M tuberculosis. Among these isolates, six different genotypes were found. Five patients had not acquired the infection from the putative source. CONCLUSIONS: Reactivation of tuberculosis may occur in contacts during the development of an outbreak. In such situations, traditional contact investigations may overestimate the rate of transmission found by genotyping of M tuberculosis. When cultures are unavailable and presumed drug susceptibility patterns are based on that of contacts, such overestimation may lead to incorrect treatment of a patient. Contact investigations must be combined with genotyping of M tuberculosis to conclude how tuberculosis is transmitted. This is especially important in persons with several risk factors for infection.

Adolescent↗

PubMed2005

Cohort analysis of asylum seekers in Oslo, Norway, 1987-1995: effectiveness of screening at entry and TB incidence in subsequent years.

SETTING: Municipalities of Baerum and Oslo, Norway. OBJECTIVES: To examine the effectiveness of tuberculosis (TB) screening in asylum seekers 1987-1995, and to describe TB incidence rates after arrival. DESIGN: Register-based, retrospective cohort study of 19912 asylum seekers with a mean follow-up of 6.3 years. RESULTS: Seventy-six persons were diagnosed with TB, of whom 43 (57%) had pulmonary TB. Twenty-two cases (17 pulmonary) were found through screening at entry. Eleven persons had abnormal mass miniature X-rays (MMRs), but had inadequate follow-up and were diagnosed later through passive case finding. MMR itself had a sensitivity of 96% and a specificity of 98% for pulmonary TB, diagnosed within 1 year after arrival. TB prevalence at entry was 110/100000; for Somalis it was 577/100000. Incidence rates were stable in the total cohort after arrival, whereas rates for extra-pulmonary TB in Somalis increased. CONCLUSIONS: Screening on entry should continue, but follow-up of abnormal MMRs must be improved. There should be more emphasis on treatment of latent infection.

Adult↗

PubMed2003

Risk factors for recent transmission of Mycobacterium tuberculosis.

In recent decades, the decline of tuberculosis has stopped in Western Europe, mainly due to increased immigration from high-prevalence countries. The objective of the current study was to identify risk factors for developing tuberculosis following recent infection, in order to better target interventions. Strains from 861 culture-positive cases, diagnosed in Norway in 1994-1999, were analysed by use of restriction fragment length polymorphism (RFLP). A cluster was defined as two or more isolates with identical RFLP patterns. Risk factors for being part of a cluster were identified by univariate and multivariate analysis. A total of 134 patients were part of a cluster. These constituted 5% Asian-born, 18% Norwegian-born, 24% European-born and 29% African-born patients. Four independent risk factors for being part of a cluster were identified: being born in Norway, being of young age, being infected with an isoniazid-resistant strain and being infected with a multidrug-resistant strain. Transmission of tuberculosis may be further reduced by improving case management, contact tracing, preventive treatment, screening of immigrants and access to health services for the foreign-born population.

Adolescent↗

PubMed2003

Tuberculosis in Norway by country of birth, 1986-1999.

OBJECTIVE: To estimate the standardised incidence ratio (SIR) of TB among the foreign-born in Norway. METHOD: The expected number of TB cases was calculated by applying the sex- and age-specific incidence rates for those born in Norway to the corresponding foreign-born population. The SIR was measured as the ratio between observed and expected number of cases. RESULTS: The expected number of TB cases was between zero and three for all selected countries; the observed number of cases was significantly higher. The SIR was highest for Africa (160, 95%CI 144-175) and lowest for USA/Canada (0.4, 95%CI 0.1-1.0). It was 883 for Somalia (95%CI 775-991), 122 for Vietnam (95%CI 106-139), 119 for Pakistan (95%CI 105-134), 115 for the Philippines (95%CI 91-144) and 49 for former Yugoslavia (95%CI 40-57). The SIR for all the foreign-born was 21 (95%CI 20-22), giving a population attributable risk of 38%. It was highest in the age group 15-39 years (95, 95%CI 89-101), and lowest for those 65 years and older (3, 95%CI 2.1-3.3). The SIR for extrapulmonary TB was also high in those aged 15-39 years (159, 95%CI 146-173). CONCLUSION: SIRs for TB differ by country and continent of birth. Understanding local epidemiology and immigration patterns will help better target prevention efforts.

Adolescent↗

PubMed2001

Molecular epidemiology of Mycobacterium tuberculosis in Norway.

The incidence of tuberculosis in Norway is one of the lowest in the world, and approximately half of the cases occur in first- and second-generation immigrants. In the present study, the genetic diversity of 92% of all strains of Mycobacterium tuberculosis isolated in Norway in 1994 to 1998 was assessed using restriction fragment length polymorphism (RFLP) analysis, with the insertion sequence IS6110 and the repetitive element DR as probes, to determine the degree of active transmission between patients. The DR probe was used as a secondary molecular marker to support or rule out clustering of strains with fewer than five copies of IS6110. After exclusion of 20 cultures representing laboratory contamination, 573 different IS6110 patterns were found among the 698 strains analyzed. Of these 573 patterns, 542 were observed only once and 31 were shared by 2 to 14 isolates. Among 81 strains (11.5%) carrying fewer than five copies of IS6110, 56 RFLP patterns were found when the results of both the IS6110 and DR methods were combined. Among the 698 strains, 570 were considered to be independent cases. A total of 14.5% of the native Norwegians and 19.7% of the foreign patients were part of a cluster. Thus, the degree of recent transmission of tuberculosis in Norway is low and the great majority of the cases are due to reactivation of previous disease. Transmission between immigrants and native Norwegians is uncommon. Two outbreaks, one among native Norwegians and one mainly among immigrants, have been ongoing for several years, indicating that, even in a low-incidence country such as Norway, with a good national program for tuberculosis surveillance, certain transmission chains are difficult to break.

Adolescent↗

PubMed2001

Low failure rate in standardised retreatment of tuberculosis in Nicaragua: patient category, drug resistance and survival of 'chronic' patients.

SETTING: IUATLD collaborative programme, Nicaragua. OBJECTIVE: To analyse reported trends in the retreatment failure rate (2SRHZE/1RHZE/5R3H3E3), and assess demographic characteristics, drug resistance and survival in patients who fail retreatment. DESIGN: A retrospective, descriptive study. Reports from 1988-1996 were analysed and records of 69 patients who failed retreatment were reviewed. RESULTS: The treatment success rate in new cases improved from 71% in 1988-1991 to 79% in 1992-1996, the default rate decreased from 16% to 10%, and the failure rate remained stable at 2-3%. The proportion of previously treated patients among all smear-positives decreased from 20% to 15%. In retreatment patients the failure rate declined from 6.6% to 4.3% and the average annual number of failures from 24 to 13. In 1992-1996, 64 patients, 0.8% of new smear-positive cases treated during this period, failed retreatment; the corresponding figures for 1988-1991 are 95 and 1.6%. Among 69 retreatment failure cases reviewed, there was male predominance and increasing age during the study period. Drug susceptibility results were available for 38, of whom 89% were resistant to isoniazid and rifampicin. The median survival of patients after failure was 3.9 years. CONCLUSION: Treatment results improved over the study period. The proportion of patients on retreatment out of all smear positives treated decreased, as did the absolute number of failures and the retreatment failure rate. Development of multidrug resistance has been largely prevented in Nicaragua; the low failure rate justifies the continued use of the standardised retreatment regimen.

Adult↗

PubMed2000

Pulmonary tuberculosis in Norwegian patients. The role of reactivation, re-infection and primary infection assessed by previous mass screening data and restriction fragment length polymorphism analysis.

SETTING: Norwegian patients with pulmonary tuberculosis notified to the National Tuberculosis Register in 1975, 1985 and 1995. OBJECTIVE: To assess the proportion of cases attributable to endogenous reactivation, exogenous re-infection and primary infection. DESIGN: We reviewed patients notified with sputum smear and/or culture confirmed pulmonary tuberculosis in 1975 (50% random sample, 95 cases), 1985 (133 cases) and 1995 (70 cases). Information on previous chest X-ray, tuberculin and BCG status was collected from mass screening data files. Strains from 54 patients in 1995 were analysed by IS6110 restriction fragment length polymorphism (RFLP) typing and compared with culture-positive patients notified between 1994 and 1997. RESULTS: Most patients had previously had tuberculosis (65% in 1975, 53% in 1985 and 61% in 1995), either notified with tuberculosis or with X-ray findings indicating previous tuberculosis. Another 10% had a prior infection, but normal X-rays. No previous tuberculosis infection or disease was found in 10% in 1975, 19% in 1985, and 16% in 1995. Of 54 patients with RFLP results, three were caused by laboratory contamination. Of the remaining 51, eight (16%) belonged to a cluster. Among 45 patients with results of both RFLP typing and mass screening, 37 (82.2%) were probably caused by reactivation, six (13.3%) by re-infection and two (4.4%) by primary infection. CONCLUSION: Pulmonary tuberculosis in Norwegian patients can mainly be attributed to reactivation, predominantly in persons with previous changes on chest X-ray.

Adolescent↗

PubMed1998

[Differences in morbidity between the Eastern central city district and the suburban Western district of Oslo].

Oslo, the capital of Norway, has a population of 500,000. Living conditions vary considerably within the city, and the mortality rate in the most deprived area is almost three times as high as in the most affluent one. We wanted to explore how morbidity varies within Oslo. We used four town-wide disease registers to study the prevalence of the four diseases in the most deprived and the most affluent part of the city. We found that tuberculosis occurs more frequently in the poor area, while type 1 diabetes mellitus in children occurs more frequently in the most affluent area. For multiple sclerosis and rheumatoid arthritis we could not find any differences between the areas.

Adult↗

PubMed1997

Successful management of a national tuberculosis programme under conditions of war.

OBJECTIVE: To compare treatment results before and after introduction of short course tuberculosis chemotherapy and to identify factors affecting the results. DESIGN/SETTING: An eight-month chemotherapy regimen for smear-positive pulmonary tuberculosis was introduced in Nicaragua in 1984 with external financial assistance. We performed a retrospective record review to compare treatment results before and after introduction of short-course chemotherapy. Information on support services and programme administration, availability of hospital beds for tuberculosis patients, access to health services and the economic and war situation in the two periods was assessed. RESULTS: The overall success ratio improved by 39% between the two periods reviewed, in spite of evidence of a deteriorating economy and escalation in civil war. A success ratio of 71% was achieved and we estimate that between 80 and 90% of registered cases stopped transmitting tuberculosis. The best results were obtained in the treatment of previously untreated patients with eight-month chemotherapy and in retreatment of relapses. The worst results were obtained in retreatment of defaulters. Analysis of the findings by region suggests that short-course chemotherapy was important, but not enough by itself to guarantee success. Factors likely to have influenced treatment results are: commitment by health authorities in guaranteeing personnel and hospital beds, training of personnel, and supervision of service delivery. Possibilities for further improvement are discussed. CONCLUSIONS: Good results were achieved in tuberculosis control with the introduction of short-course chemotherapy in spite of poverty and war. Government commitment and simultaneous improvement in supportive services and programme management is important when introducing short-course chemotherapy in low income countries.

Antitubercular Agents↗

PubMed1996

Deaths from active tuberculosis: can we rely on notification and mortality figures?

SETTING: Notification rates and mortality are the main indicators in the epidemiology of tuberculosis. While errors in case notification are known to be considerable, the quality of the data on deaths is largely unknown. OBJECTIVE: To validate the quality of data on deaths from active tuberculosis. DESIGN: We compared deaths from active tuberculosis in Statistics Norway with the National Tuberculosis Register (NTR) and cases found by autopsy in two Norwegian counties in 1977-1989. We also assessed the diagnostic classification and inclusion criteria for tuberculosis. RESULTS: 110 patients were entered into the study. We excluded 30 of 106 patients in Statistics Norway, primarily because of inactive tuberculosis (16) or minimal lesions (7). We found an additional 20 patients in the NTR and 14 more from autopsy reports. These missing cases were registered in Statistics Norway with a different diagnosis (28), inactive tuberculosis (4) or not found (2). Nineteen of them were diagnosed with tuberculosis by autopsy and five by cultures reported after death. We altered the diagnostic classification of underlying cause in 14% and found tuberculosis to be the underlying cause in 65 patients. CONCLUSION: The mortality rate from active tuberculosis in Statistics Norway was fairly correct, but one-third were under-reported and one-third over-reported. The mortality rate includes only half of all the deaths from active tuberculosis. All the cases in which active tuberculosis is mentioned on the death certificate are a clearer indication of tuberculosis deaths.

Autopsy↗

PubMed1995

[Tuberculosis trends in Norway--has the decline stopped?].

The aim of the study was to present the trend as regards tuberculosis in Norway since 1950, on the basis of data on incidence and mortality in the total population and infection rate among pupils leaving primary school. The decline in incidence continued until the late 1980s. While the decline was 11% per year during the period 1950-74, it has been slower in recent years. In 1990-92 the incidence level was somewhat higher than in 1989, but figures for 1993-94 indicate a new decline. Mortality declined more slowly after the mid-1970s; a similar trend is found for prevalence of infection among pupils. The incidence is among the lowest in Europe. The proportion of cases among immigrants increased gradually from 4% in 1977 to 40% in 1993. Among the Norwegian-born population the incidence rate of infectious pulmonary tuberculosis has shown a steady decline, also during the last decades. Norwegian-born cases are mainly elderly persons infected many decades ago. New infection is probably rare, and the proportion of infected persons is gradually declining.

Disease Notification↗

PubMed1995

[Tuberculosis control in Scandinavia].

Compared with the rest of the world, the situation regarding tuberculosis is favourable in the Nordic countries. In 1993, the incidence for persons born in respective country (per 100,000 of the population) was 4.1 in Denmark, 3.2 in Iceland and Sweden, 3.8 in Norway and 10.0 in Finland. The respective average figures for foreign-born residents were 6-14 times higher. Programmes for contending with tuberculosis have been uniform in the Nordic countries, with the exception of BCG (bacillus Calmette-Guérin) vaccination policy, though childhood tuberculosis is rare in the area. However, tuberculosis represents a manifest problem among the foreign-born population, first and foremost among the increasing number of refugees.

Adolescent↗

PubMed1994

[The global tuberculosis problem. An apparition from history?].

Tuberculosis is increasing, partly because of concomitant HIV-infection, but with poverty and lack of social welfare and public health services contributing substantially. Current treatment for tuberculosis has proved efficacious also in HIV-infected patients, and so far seems to have prevented increased transmission of the disease in Tanzania. Strictly controlled chemotherapy provides the only hope of preventing the emergence of multi-resistant tubercle bacilli. The World Bank has evaluated tuberculosis control as the most cost-effective form of health intervention among adults. Norway has made a substantial contribution to the development of a model for tuberculosis control in developing countries and to international mycobacterial research; and therefore has a special responsibility to meet the new challenge.

Africa↗

PubMed1994

Why do our patients die of active tuberculosis in the era of effective therapy?

SETTING: All patients with tuberculosis as a primary or underlying cause of death who were autopsied at the Institute for Lung Diseases and Tuberculosis, Sremska Kamenica, in the former Yugoslavia, between 1981 and 1990 were investigated. OBJECTIVE: To study why people die of active tuberculosis in the era of effective chemotherapy and to identify factors contributing to death. DESIGN: In a retrospective investigation, this index group was compared with a control group consisting of patients who suffered from tuberculosis over the same period but who improved and were discharged from hospital. RESULTS: A significant difference in age (P < 0.05) was found between those patients who died with an antemortem-established diagnosis and those who died with unrecognised tuberculosis (median 49 and 60 years respectively). When it came to the index group, 28 patients (56%) had one or more risk factors and the frequency of alcohol abuse was significantly higher (P < 0.001). Antituberculosis treatment had been introduced in 27 cases (54%). The median duration of hospitalization before therapy was 2 days and the median duration of antituberculosis therapy was 7 days. Of the 23 untreated tuberculosis patients, 74% died within the first 4 days. CONCLUSION: Delay in the detection of tuberculosis was the main factor contributing to death in our patients.

Adult↗

PubMed1994

Tuberculosis case-finding in Nicaragua: evaluation of routine activities in the control programme.

SETTING: The new International Union against Tuberculosis and Lung Disease (IUATLD) tuberculosis strategy developed in the 1980s in Tanzania, Malawi and Mozambique, was simultaneously implemented in Nicaragua. OBJECTIVE: Present results of case-finding, identify trends in incidence and limitations in case-finding and reporting. DESIGN: Data are based upon the traditional reporting system until 1987, replaced as the programme was reorganized. Data were also collected directly from the Central Laboratory, Programme and Laboratory registers during supervision of health centres. RESULTS: Quality control of sputum smears shows 1.8% discordance between peripheral and central laboratories. Notification rate of smear-positive tuberculosis declined 1.7% yearly 1983-1991 and 2.6% for all cases. Half of the patients are new smear-positive pulmonary cases, 40% smear-negative pulmonary cases. Relapses represent 11-13% of all smear-positive patients, children 7-30% of all cases. One-third of extrapulmonary tuberculosis cases are pleural effusions, another third lymphadenitis. 41% of adult patients entered as smear-negative in the programme had no smear reported in the laboratory. CONCLUSIONS: Quality control of sputum smears was established and the reporting system improved in spite of adverse conditions. Notification rate declined gradually. Smears should be done in all patients classified as smear-negative pulmonary tuberculosis.

Adolescent↗