Impact of immigration and HIV infection on tuberculosis incidence in an area of low tuberculosis prevalence

The aim of this study is to assess the effects of immigration from countries with a high prevalence of tuberculosis (HPCs), of HIV/AIDS prevalence, and the ageing of the indigenous population, on tuberculosis distribution in a low-prevalence area (LPCs), the Piedmont Region of Italy. Tuberculosis incidence and HIV cases were identified by linking records from the surveillance systems. Overall, 640 tuberculosis cases were identified and crude annual incidence was found to be 17.3/100000. The incidence rate ratio for HIV infection as a risk factor for tuberculosis (11.4 and 51.9 among individuals from HPCs and LPCs respectively) was greater than that for immigration from HPCs (6.7 and 30.9 among HIV+ and HIV- individuals). Immigration accounted for a larger number of incident cases [population attributable risk % (PAR %): 31.8 and 52.8% among HIV+ and HIV- individuals] than did HIV infection (PAR %: 5.4 and 11.1% among individuals from HPCs and LPCs). Efforts should be made to identify and treat young immigrants from HPCs.     

Tuberculosis infection and disease among schoolchildren: the influence of the HIV epidemic and of other factors

BACKGROUND: The HIV/AIDS epidemic has caused an excess of tuberculosis cases in Spain and in other countries, but its impact on tuberculosis infection is less well understood. This study presents a massive screening undertaken to estimate the prevalence of tuberculous infection in a cohort of primary school entrants. The evolution of the risk of infection is studied by comparison with previous data in the same population. METHODS: Tuberculin skin test screening with 2TU of PPD RT 23 of first grade students in the primary schools of Barcelona, in the 1994-95 school year (cohort born in 1988). Information was also sought from families of unscreened children. Contacts of PPD+ children were traced to locate index cases. The results were also linked to the case registry of the tuberculosis control programme. RESULTS: The prevalence of tuberculin reactors free of BCG vaccination among the 11,080 schoolchildren screened belonging to the 1988 cohort was 0.76%. A 3% annual decline in the annual risk of infection is estimated by comparison with previous data. The identification of 24 cases with a previous history of tuberculosis disease and of 13 cases with active disease diagnosed after the screening was possible by the follow up of these tuberculin positive children and of the information provided by families of unscreened pupils. The screening detected 1.5 new cases of tuberculosis per 1000 tuberculin tests performed. Tuberculosis infection could be traced to HIV infected tuberculosis cases for at least 6% of the positive schoolchildren. CONCLUSIONS: The decline of the annual risk of infection continues in Barcelona, although at a slower pace than before the HIV/AIDS epidemic, probably attributable to the influence of injecting drug users with smear positive tuberculosis and HIV/AIDS.     

Some clinical aspects of HIV infection in Africa

An update on clinical aspects of HIV in africa highlights new proposed clinical definitions of adult AIDS and of tuberculosis in HIV+ adults, and staging of adult HIV infection. The 1986 WHO clinical definition of AIDS has been widely used in Africa, but now research suggests that this definition has several limitations: the definition will pick up several unrelated diseases such as diabetes mellitus and renal failure. It does not ascertain cases of AIDS marked by nonopportunistic infections. Most persons with pulmonary tuberculosis may be wrongly diagnosed with AIDS by this definition. The study showed that the WHO clinical definition has good specificity and positive predictive value for HIV+ people, but its positive predictive value fell to 30% in identifying people with AIDS in Africa. New definitions should take into account any serious morbidity, tuberculosis, neurological disease, both endemic localized Kaposi's, and aggressive typical Kaposi's sarcoma, and HIV serological testing. Tuberculosis is a problem because few HIV+ people suspected of having pulmonary TB (sputum-negative TB) actually have it based on bronchoscopy, while HIV+ persons with TB experience high mortality, often from pyogenic bacteremia. HIV+ persons with TB suffer high rates of relapse, possibly related to insufficient drug treatment or reinfection. 1 study showed that 6 months of isoniazid significantly improved incidence of TB over 30 months of follow-up. Staging of AIDS in Africa based on degree of immunosuppression was proposed as: 1) clinically inapparent HIV infection marked by pulmonary TB, soft tissue infections, and community acquired pneumonia; 2) lymphadenopathy, oral thrush, widespread pruritic maculopapular rash, herpes zoster, enteric illness, dysentery, and Kaposi's sarcoma; and 3) HIV wasting syndrome, chronic pulmonary disease, meningitis, and fever of unknown origin.     

Indigenous mortality: placing Australian aboriginal mortality within a broader context.

The purpose of this study was to evaluate whether contemporary Australian Aboriginal mortality patterns are different from those exhibited by Canadian Registered Indians, New Zealand Maoris, and American Indians and Alaskan natives. Data on Australian Aborigines were procured from published studies conducted in New South Wales, the Northern Territory, Queensland, and Western Australia; while data on Canadian Registered Indians, New Zealand Maoris, and American Indians and Alaskan natives were obtained respectively from unpublished tables produced by Health and Welfare Canada, the National Health Statistics Centre, and the Indian Health Service. Mortality patterns were compared by evaluating differences in life expectancy and in age- and cause-specific patterns of death. This analysis demonstrates that although Australian Aborigines, Canadian Registered Indians, New Zealand Maoris, and American Indians and Alaskan natives have similar patterns of high adult mortality, Australian Aborigines are generally characterized by lower life expectancies at birth and higher age- and cause-specific death rates. Overall, these findings suggest that the mortality patterns of Australian Aborigines are strikingly different from those exhibited by the other three indigenous populations and that existing information on risk, psychosocial, and genetic factors does not really explain why Australian Aborigines as compared to these other indigenous groups have such high rates of death and low life expectancy.     

科学推进结核病防控策略实现“十三五”结核病防治规划

结核病是严重危害居民健康的重大传染病。我国结核病疫情相当严重,是全球结核病高负担国家之一。我国如期实现了向国际社会承诺的结核病控制阶段性目标,结核病死亡率明显下降。高感染率、高患病率、高耐药率,发现率、认知率、规则服药率还差强人意以及患病率下降缓慢等构成中国结核病的流行特点。当前我国结核病防控形势严峻,为实现《"十三五"全国结核病防治规划》,必须依法和科学地推进结核病防控策略:将结核病防治工作作为重要民生建设内容,列入各地国民经济和社会发展规划,纳入政府目标管理考核内容;加强结核病防治工作信息化建设;健全包括结核病防治专业机构、结核病定点医疗机构和基层医疗卫生机构的服务体系,实施传染性肺结核患者住院治疗;做好结核病危险人群的关怀、监测、防治和健康教育工作;广泛深入开展有关结核病的严重性和危害性的宣传教育,做到每一个结核病人都得到关怀。     

Prevalence of tuberculosis and HIV infections among participants in an intravenous drug user risk-control program]

BACKGROUND: To determine the prevalence of tuberculosis and HIV infection in addition to the related factors among a population of participants in the risk control program in the town of Lleida. METHODS: The sample was comprised of the newly-enrolled participants in the program in April-June 1996, among whom a questionnaire was handed out for collecting the data concerning the variables involved: age, gender, results of the tuberculin test, BCG vaccination, knowledge of the serology regarding HIV, former imprisonment and number of years having used heroin. The prevalence of the tuberculosis and HIV infection was calculated to a 95% confidence interval (CI). The relating of these two variables to all other variables in the study was determined by means of the odds ratio (OR) and its 95% CI. RESULTS: One hundred and fifty (150) patients were seen, 45 of whom were newly enrolled participants. Eighty percent (80%) were males, averaging 31.1 years of age. The prevalence of this dual infection was 8.9% (95% CI 2.8-22.1). The prevalence of the tuberculosis infection was 27.3% (95% CI 12.4-43.0), being higher among former prison inmates (OR = 3.4; 95% CI 0.5-27.4). The prevalence of the HIV infection was 36.1% (95% CI 21.3-53.8), being greater among those who had been using heroin for longer than 11 years (OR = 7.3; 95% CI 1.0-65.9). CONCLUSIONS: Former imprisonment is the main risk factor for tuberculosis infection. The number of years of heroin use are related to the HIV infection, especially when longer than 11 years. The risk control programs in our country should carry out activities aimed at monitoring tuberculosis and HIV infection.     

国内外老年人结核病流行趋势及影响因素研究进展

老年人群结核病已成为全球亟待解决的重大公共卫生问题,其高发病率、高患病率、高不良反应率和高死亡率的疾病特点严重影响了老年人群的晚年生活与健康。结核病兼具慢性病和传染性疾病的特征,受多种因素影响,分析老年人结核病的流行病学特征,明确老年人结核病的危险因素,对老年人结核病的防控有重要指导价值。本文对国内外老年人结核病的流行趋势和影响因素进行了综述,为老年人结核病进一步的研究和干预提供了参考依据。     

艾滋病与结核病患者双重感染检出率及其影响因素的调查

[目的]了解广西艾滋病人中结核病患病率,结核病患者中HIV感染检出率;调查广西艾滋病患者发生结核病及结核病患者感染HIV的影响因素。[方法]对260例艾滋病患者及580例结核病患者进行双重感染检出率及其影响因素的问卷调查,并查看病例。[结果]260例HIV/AIDS患者中结核病患病率为35.0%（肺结核为29.2%,肺外结核为5.8%）,580例结核病患者HIV感染检出率为2.8%;影响260例艾滋病患者发生结核病的主要影响因素为月收入,影响580例结核病患者感染HIV的主要影响因素为吸毒和商业性行为。[结论]艾滋病患者发生结核病的机率高,月收入低者易发生结核病;结核病患者中HIV感染检出率高于一般人群,吸毒和商业性行为是结核病患者感染HIV的主要途径。     

Tuberculosis in patients with HIV infection

Tuberculosis is a clear example of infection that requires cellular immunity for its control. The spread throughout the world of the Human Immunodeficiency Virus (HIV) resulted in its interaction with tuberculosis altering the descending curve of the latter disease in some developed countries, and brought an aggravation of the problem in other countries with few economic and health resources and where tuberculosis was endemic. HIV increases the risk of reactivation of latent tuberculosis infection and accelerates progression after infection or reinfection; on the other hand, TB aggravates the prognosis of patients infected with HIV. This article sets out the differential aspects in the clinical manifestations of TB amongst populations with and without HIV infection; we also comment on some special characteristics in the treatment of tuberculosis in HIV patients. With the exception of primary cutaneous infections produced by accidental inoculation and infantile lymphadenitis, the majority of the cases of disease due to non-tuberculosis mycobacteria (NTM) affect patients with certain predisposing factors. In the case of patients with AIDS, the deep immunological disorder provoked by HIV brings a particular susceptibility to suffering invasive disease due to certain NTM, principally M. avium complex and M. kansasii.     

HIV testing and treatment among tuberculosis patients --- Kenya, 2006-2009

In resource-limited settings, high case-fatality rates are seen among tuberculosis (TB) patients with human immunodeficiency virus (HIV) infection, especially during the early months of TB treatment. HIV prevalence among TB patients has been estimated to be as high as 80%--90% in some areas of sub-Saharan Africa. In 2004, the World Health Organization (WHO) recommended increasing collaboration between HIV and TB programs. Since then, many countries, including Kenya, have worked to increase TB/HIV collaborative activities. In 2005, the Kenya Division of Leprosy, Tuberculosis, and Lung Disease (DLTLD) added questions regarding HIV testing and treatment to the existing TB surveillance system.* This report summarizes HIV data collected from Kenya's extended TB surveillance system during 2006--2009. During this period, HIV testing among TB patients increased from 60% in 2006 to 88% in 2009, and the prevalence of HIV infection among TB patients tested decreased from 52% to 44%. In 2009, 92% of HIV-infected TB patients received cotrimoxazole prophylaxis for the prevention of opportunistic infections. Although these data highlight the increase in HIV services provided to TB patients, only 34% of HIV-infected TB patients started antiretroviral therapy (ART) while being treated for TB. Innovative interventions are needed to increase HIV treatment among TB patients in Kenya, especially considering the 2009 WHO guidelines recommending that all HIV-infected TB patients be started on ART as soon as possible, regardless of CD4 count. Although these guidelines have not yet been implemented in Kenya, officials are working to identify methods of increasing access to ART for TB patients.     

Tuberculosis and the HIV epidemic: increasing annual risk of tuberculous infection in Kenya, 1986-1996.

OBJECTIVES: The purpose of this study was to assess the impact of the increased incidence of tuberculosis (TB) due to HIV infection on the risk of TB infection in schoolchildren. METHODS: Tuberculin surveys were carried out in randomly selected primary schools in 12 districts in Kenya during 1986 through 1990 and 1994 through 1996. Districts were grouped according to the year in which TB notification rates started to increase. HIV prevalence in TB patients and changes in TB infection prevalence were compared between districts. RESULTS: Tuberculous infection prevalence rates increased strongly in districts where TB notification rates had increased before 1994 (odds ratio = 3.1, 95% confidence interval = 2.3, 4.1) but did not increase in districts where notification rates had increased more recently or not at all. HIV prevalence rates in TB patients were 50% in districts with an early increase in notification rates and 28% in the other study districts. CONCLUSIONS: Countries with an increasing prevalence of HIV infection will need additional resources for TB control, not only for current patients but also for the patients in additional cases arising from the increased risk of TB infection.     

Prevalence of Mantoux positivity and annual risk of infection for tuberculosis in New South Wales prisoners, 1996 and 2001

OBJECTIVES: This study compares the prevalence of Mantoux positivity among prisoners in NSW in 1996 and 2001 and examines factors associated with Mycobacterium tuberculosis infection. DESIGN: Cross-sectional random samples of prisoners, including a longitudinal cohort of prisoners screened in both 1996 and 2001. Setting: 29 correctional centres. PARTICIPANTS: 747 men and 167 women participated in the 2001 NSW Inmate Health Survey; a cohort of 104 prisoners from the 1996 and 2001 NSW Inmate Health Surveys. RESULTS: The prevalence of Mantoux positivity remained stable between 1996 and 2001 (12% and 14%, p = 0.2), and increased among prisoners from Asian backgrounds (21% and 47%, p = 0.02). The annual risk of infection in the cohort among those detained continuously between 1996 and 2001 was 3.1%, and among recidivists it was 2.7% (p = 0.6). CONCLUSION: The risk of M. tuberculosis infection for Australian prisoners is assessed to be approximately four times higher than that for the community, however there is no attributable risk to the prison environment itself.     

湖南省HIV/AIDS人群结核发病影响因素的巢式病例对照研究

目的 探讨HIV/AIDS人群发生结核病的危险因素.方法 采用1:2匹配的巢式病例对照研究方法分析HIV/AIDS人群发生结核的危险因素.结果 对1018例未患结核的HIV/AIDS人群随访观察1年,累计观察736.75人年,共检查出结核病患者62例,HIV/AIDS人群结核病发病密度为8.42人/100人年(62人/736.75人年).文化程度(OR=0.483)、卡介苗接种史(OR=0.561)、CD_4~+T淋巴细胞数(OR=0.356)、无业(OR=1.976)、单身(OR=2.646)和吸烟(OR=2.215)等因素与HIV/AIDS人群发生结核病有关.结论 文化程度高、有卡介苗接种史和CD_4~+T淋巴细胞数高是HIV/AIDS人群患结核病的保护因素;无业、单身和吸烟是HIV/AIDS人群患结核病的危险因素.     

Aspects of tuberculosis in Africa. 1. Tuberculosis in Africa in the AIDS era--the role of chemoprophylaxis.

An estimated 2.8 million people in Africa have dual infections with tuberculosis and human immunodeficiency virus (HIV). Because of the increasing numbers of cases of tuberculosis as a consequence of the HIV epidemic, chemoprophylaxis may become a cost effective tuberculosis control measure in high prevalence countries. Although isoniazid (INH) is the only drug evaluated in controlled trials of preventive tuberculosis therapy, studies are now under way to determine the efficacy of INH and other drugs, including rifampicin and pyrazinamide, in preventing tuberculosis reactivation in persons with HIV infection. If chemoprophylaxis is effective in persons with dual infection, further studies will be required to determine whether chemoprophylaxis is cost effective for tuberculosis prevention and control and whether it is feasible to introduce it as a community control measure.     

Factors associated with latent tuberculosis infection in the contacts of tuberculosis patients

BACKGROUND: As tuberculosis control programs have reached acceptable levels in the identification and treatment of persons with active tuberculosis, the next step should be to develop methods of preventing new cases. Persons with latent tuberculosis infection (LTI) are considered to have a higher risk of developing active tuberculosis. The objective of this study was to evaluate the prevalence of LTI and its associated factors in the contacts of tuberculosis patients. METHODS: We studied the contacts of tuberculosis patients who were examined in the Center for Tuberculosis Control and Prevention in Lleida (Spain) from 1991-1997. Factors associated with the index case (demographic, radiographic, bacteriologic and therapeutic) and tuberculin skin test results and demographic data in contacts were collected. Data on HIV infection, injection drug use and alcohol consumption in tuberculosis patients were also collected. The associations were assessed by obtaining crude and adjusted odds ratios. RESULTS: The prevalence of LTI among contacts was 36.1% (780/2,161). In the multivariate analysis a higher frequency of LTI was detected in contacts older than 14 years (ORa = 3.34; 95% CI, 2.51-4.45), contacts who had a higher degree of exposure to the index case (ORa = 1.96; 95% CI, 1.59-2.42), contacts of pulmonary tuberculosis patients (ORa = 1.54; 95% CI, 1.01-2.35), contacts of patients with a positive sputum smear (ORa = 1.51; 95% CI, 1.15-1.99), contacts of patients with caverns on chest x-ray (ORa = 1.27; 95% CI, 1.01-1.61) and contacts of patients with delayed treatment (ORa = 1.31; 95% CI, 1.05-1.62). CONCLUSIONS: The overall prevalence of LTI in the contacts of patients with tuberculosis was high. Among the factors studied, delayed treatment in the index case was independently associated with the frequency of LTI in tuberculosis contacts. Measures for the early diagnosis and treatment of tuberculosis should be intensified.     

It's not just who you are but where you live: an exploration of community influences on individual HIV status in rural Malawi

Approximately 1 million people are infected with Human Immunodeficiency Virus (HIV) in Malawi. Despite efforts aimed at changing individual risk behaviors, HIV prevalence continues to rise among rural populations. Both previous research and the Political Economy of Health framework suggest that community-based socio-economic factors and accessibility may influence HIV transmission; however, these community factors have received little empirical investigation. To fill this gap, this research uses data from a nationally representative probability sample of rural Malawians combined with small area estimates of community socio-economic and accessibility data in logistic regression models to: 1) reveal relationships between community factors and individual HIV status; 2) determine whether these relationships operate through individual HIV risk behaviors; and 3) explore whether these associations vary by gender. Community socio-economic factors include relative and absolute poverty; community accessibility factors include distance to roads, cities, and public health facilities. Individual HIV risk behaviors include reported condom use, sexually transmitted infections, multiple partnerships, and paid sex. Results show that higher community income inequality, community proximity to a major road, and community proximity to a public health clinic are associated with increased odds of HIV for women. For men, community proximity to a major road and community proximity to a public health clinic are associated with increased odds of HIV infection. These direct relationships between community factors and individual HIV status are not mediated by individual HIV risk behaviors. The Political Economy of Health frames the discussion. This study provides evidence for expanding HIV prevention efforts beyond individual risk behaviors to consideration of community factors that may drive the HIV epidemic in rural Malawi.     

Guidelines for preventing the transmission of tuberculosis in health-care settings, with special focus on HIV-related issues

The transmission of tuberculosis is a recognized risk in health-care settings. Several recent outbreaks of tuberculosis in health-care settings, including outbreaks involving multidrug-resistant strains of Mycobacterium tuberculosis, have heightened concern about nosocomial transmission. In addition, increases in tuberculosis cases in many areas are related to the high risk of tuberculosis among persons infected with the human immunodeficiency virus (HIV). Transmission of tuberculosis to persons with HIV infection is of particular concern because they are at high risk of developing active tuberculosis if infected. Health-care workers should be particularly alert to the need for preventing tuberculosis transmission in settings in which persons with HIV infection receive care, especially settings in which cough-inducing procedures (e.g., sputum induction and aerosolized pentamidine [AP] treatments) are being performed. Transmission is most likely to occur from patients with unrecognized pulmonary or laryngeal tuberculosis who are not on effective antituberculosis therapy and have not been placed in tuberculosis (acid-fast bacilli [AFB]) isolation. Health-care facilities in which persons at high risk for tuberculosis work or receive care should periodically review their tuberculosis policies and procedures, and determine the actions necessary to minimize the risk of tuberculosis transmission in their particular settings. The prevention of tuberculosis transmission in health-care settings requires that all of the following basic approaches be used: a) prevention of the generation of infectious airborne particles (droplet nuclei) by early identification and treatment of persons with tuberculous infection and active tuberculosis, b) prevention of the spread of infectious droplet nuclei into the general air circulation by applying source-control methods, c) reduction of the number of infectious droplet nuclei in air contaminated with them, and d) surveillance of health-care-facility personnel for tuberculosis and tuberculous infection. Experience has shown that when inadequate attention is given to any of these approaches, the probability of tuberculosis transmission is increased. Specific actions to reduce the risk of tuberculosis transmission should include a) screening patients for active tuberculosis and tuberculous infection, b) providing rapid diagnostic services, c) prescribing appropriate curative and preventive therapy, d) maintaining physical measures to reduce microbial contamination of the air, e) providing isolation rooms for persons with, or suspected of having, infectious tuberculosis, f) screening health-care-facility personnel for tuberculous infection and tuberculosis, and g) promptly investigating and controlling outbreaks. Although completely eliminating the risk of tuberculosis transmission in all health-care settings may be impossible, adhering to these guidelines should minimize the risk to persons in these settings.     

中国结核病疾病负担现状

结核病是由结核分枝杆菌引起的传染病,以肺结核为主要形式。中国是全球结核病高负担国家之一。近年中国结核病估算发病率虽持续降低,但下降速度较为缓慢。结核病防治工作仍面临着估算发病数与报告发病数之间的差距增大、中老年人群发病率高、农牧民发病例数多、西部地区疾病负担较重等问题。此外,结核分枝杆菌潜伏感染、耐药结核病、结核分枝杆菌合并HIV感染、肺外结核等也在一定程度上加剧了结核病的疾病负担。本文对结核病流行现状、三环节两因素、疾病负担等方面进行综述,为结核病防控对策的制定提供参考。     

Spatial and socio-behavioral patterns of HIV prevalence in the Democratic Republic of Congo

This study uses a 2007 population-based household survey to examine the individual and community-level factors that increase an individual’s risk for HIV infection in the Democratic Republic of Congo (DRC). Using the 2007 DRC Demographic Health Surveillance (DHS) Survey, we use spatial analytical methods to explore sub-regional patterns of HIV infection in the DRC. Geographic coordinates of survey communities are used to map prevalence of HIV infection and explore geographic variables related to HIV risk. Spatial cluster techniques are used to identify hotspots of infection. HIV prevalence is related to individual demographic characteristics and sexual behaviors and community-level factors. We found that the prevalence of HIV within 25 km of an individual’s community is an important positive indicator of HIV infection. Distance from a city is negatively associated with HIV infection overall and for women in particular. This study highlights the importance of improved surveillance systems in the DRC and other African countries along with the use of spatial analytical methods to enhance understanding of the determinants of HIV infection and geographic patterns of prevalence, thereby contributing to improved allocation of public health resources in the future.     

AIDS and tuberculosis in central Tunisia]

7 men and 2 women seropositive for HIV were carefully screened for tuberculosis in the internal medicine service of a hospital in Sousse, central Tunisia, and all tuberculosis patients aged 20-50 years registered at the tuberculosis treatment center in Sousse between May 1987-December 1988 were screened for HIV infections using the ELISA test. The HIV seropositive patients ranged in age from 21-42 years and averaged 28 at the time of diagnosis. Marriage to an HIV-positive man was the only risk factor for the 2 seropositive women. 1 of the men had hemophilia and the rest had travelled abroad and used drugs or had homosexual or heterosexual relations while outside Tunisia. 4 of the 9 HIV positive patients were diagnoses with tuberculosis, 2 with isolated pulmonary tuberculosis, 1 with pulmonary and hepatoslenic tuberculosis, and 1 with a cervical ganglionary tuberculosis. 3 of the 4 with tuberculosis had apparently normal thoracic X-rays. The 4 were treated with the normal course of antitubercular drugs for a year or more. Screening for HIV in the 104 tuberculosis patients aged 20-50 years revealed no cases of HIV infection. Tuberculosis appears to be 1 of the most frequent opportunistic infections among patients seropositive for HIV, but it is not an indicator or predictor of HIV infection in central Tunisia as it reportedly is in some African countries.