Tuberculosis among health care workers in a short working period

BACKGROUND: Tuberculosis (TB) is an important problem among health care workers (HCWs), both in Turkey and in other countries. The purpose of this study was to determine the risk ratio and features of tuberculosis (TB) among health care workers (HCWs) at a teaching hospital in southeast Turkey. METHODS: In a hospital-wide study at Dicle University Hospital, a referral center in southeast Turkey, data from HCWs with TB were collected from clinic and hospital records. The incidence and relative risk (RR) of TB among HCWs between 1986 and 2000 were analyzed and evaluated retrospectively according to TB incidence in the general population of Turkey. RESULTS: In this 15-year period, there were 22 HCWs with pulmonary tuberculosis (9 men, 13 women; 4 doctors, 13 nurses, 5 paramedics) out of an average of 734 workers per year over the study period. The mean age of the doctors was 27.1 years; nurses, 20.6 years; and paramedics, 30.5 years. The mean working experience of HCWs was 3.5 years (2.8 years for doctors, 2.8 years for nurses, 6.4 years for paramedics). The mean incidence of TB among the general population of Turkey between 1986 and 2000 was 40.8 of 100,000 persons. The mean incidence of tuberculosis in all HCWs of the hospital was 199.9 of 100,000 persons (RR = 4.9), 127.1 of 100,000 persons in doctors (RR = 3.1), 274.4 of 100,000 persons in nurses (RR = 6.7), and 160.2 of 100,000 persons (RR = 3.9) in paramedics. CONCLUSION: Hospital acquired tuberculosis is prominent among young nurses who work in high-risk departments.     

Relationship of ARTI to incidence and prevalence of tuberculosis in a district of south India.

OBJECTIVE: To validate the currently used empirical relationship between annual risk of tuberculous infection (ARTI) and incidence and prevalence of smear-positive cases. SETTING: Two disease surveys to estimate the prevalence and incidence of tuberculosis (TB) among adults in Tiruvallur district, south India, and a tuberculin survey to estimate the ARTI among children. RESULTS: The incidence of TB was estimated to be 82 and prevalence 210 per 100,000 population and ARTI 1.6%. We estimated that 1% ARTI corresponded to 51 new and 131 prevalent cases. CONCLUSION: The currently used empirical relationship between ARTI and incidence can be used by programme managers as an effective monitoring tool.     

Estimation of TB incidence by labor status

OBJECTIVE: To estimate TB incidences by labor status in 2005 and trend since 1987. METHODS: TB cases registered in 2005 are derived from TB surveillance system and categorized by labor status. Populations by labor status in 2005 are derived from national labor force survey. TB incidences by sex, age and labor status (attending school, regular employee, self-employed, temporary & daily employee, housekeepers, jobless & others) were estimated. Differences of TB incidence are discussed with data of population surveys of foreign students/workers and medical/health workers, and other resources of national surveys. Trend of TB incidence by labor status and sex were estimated since 1987 and current problems in tuberculosis control were discussed. RESULTS: Estimates of 2005 show higher TB incidences in male and female unemployed/others and male temporary/daily employees and that of housekeepers shows lower incidence. Regular employees and self-employed/house-workers show intermediate level incidences. Incidence of students was highest in 20s due to foreigners from TB prevalent countries. Female regular workers in 20s show higher incidence than male due to higher incidence among public health/medical employees. Trend of TB incidence since 1987 to 2005 shows stagnation in all labor status during second half of 1990s. In recent years, lower reduction rate was seen in most labor statuses. CONCLUSION: Present estimates of TB incidence by labor status show high TB incidences among unemployed/others, male temporary/daily employees, foreigners, and female public health/medical employees. Recent stagnation in incidence among most labor statuses (especially students and unemployed/others) should be followed-up carefully.     

High risk of tuberculosis in systemic lupus erythematosus?

The incidence and severity of tuberculosis (TB) in patients with systemic lupus erythematosus (SLE) varies greatly among different series. In addition, prospective data are scarce. The aim of this study is to analyse the frequency and severity of TB in our cohort of lupus patients. We analysed data from a prospective database of a single center cohort of 232 patients with SLE (ACR criteria). Prophylaxis with isoniazid was not regularly administered. We identified all cases of TB diagnosed during 10 years (January 1994 to December 2003). The following variables were analysed: annual incidence of TB, location of infection and response to therapy. Data from published series reporting on the incidence of TB among SLE patients were extracted. Three patients (1.3%) suffered clinically manifest TB in 1603 patient-years of follow-up, resulting in an incidence of 187 cases/100,000 patient-years (95% CI 39-547). The pooled annual incidence of TB infection in our area during this period was 30/100,000 individuals. We recorded two cases of pulmonary TB and one case of tuberculous pleurisy. All patients had good response to therapy. The annual incidence of TB among SLE patients in other series, most of them from developing countries, varied between 150/100,000 patients in Turkey and 2450/100,000 patients in India. Of note, high prevalence of extrapulmonary forms as well as elevated TB-associated mortality was reported in most series. TB was more frequent in SLE patients than expected in the general population. We did not see any cases of disseminated infection and all patients had good response to treatment. Our data compare favourably in terms of incidence, severity and outcome with those from highly endemic areas.     

Incidence and risk factors for pulmonary tuberculosis among the poor in the northern region of Poland

SETTING: The falling trends in pulmonary tuberculosis (PTB) incidence observed in European countries may be due both to an improving epidemiological situation and to a shift of tuberculosis (TB) towards socially important subpopulations; this trend may cause some TB cases to go unnoticed. Identification of such risk groups should be the basis for prevention programmes aimed at containing the spread of the disease. OBJECTIVE: To evaluate the incidence and risk factors for PTB among the poor. DESIGN: The study material was based on the data of 7380 people living in poverty, including 243 homeless adults, aged between 18 and 96 years. Potential medical and socio-economic risk factors were evaluated with regard to PTB incidence. RESULTS: The TB incidence rate in the group studied was estimated at 730 per 100,000 population. The main risk factor was homelessness, with a TB incidence rate in the homeless group of 4290/100,000. According to our data, socio-economic factors correlated much more closely with a final TB diagnosis than subjective disease symptoms. CONCLUSIONS: Efficient TB control requires prevention programmes aimed at systematic monitoring of the homeless. A population with such a high proportion of TB patients is a dangerous source of TB.     

Increasing trends in HIV and TB rates in Odessa and the Ukraine

Notification rates for HIV and tuberculosis (TB) have increased in the Ukraine and particularly in Odessa. In 1962, the incidence of TB in Odessa region was 178 cases per 100,000 cases, declining to 73.0, 42.0 and 41.6 cases per 100,000 in 1972, 1982 and 1992, respectively. In 2002, TB incidence and prevalence were 80.4 and 330.1/100,000 population, respectively. TB mortality in the port almost doubled from 10.2/100,000 to 21.6/100,000 between 1990 and 2001. In 2002, the HIV incidence and prevalence and AIDS incidence and prevalence were 46.4 and 241.0 cases/100,000 population and 14.5/100,000 and 26.9/100,000, respectively. There are increasing numbers of TB cases co-infected with HIV (200 in 2002), suggesting that the HIV and TB epidemics are converging. Significant effort is needed for the effective control of these two outbreaks to prevent high levels of morbidity and mortality from these diseases.     

Trends in tuberculosis and the influence of HIV infection in northern Malawi, 1988-2001

OBJECTIVE: To document the changing incidence and patterns of tuberculosis (TB) in rural Africa and the extent to which they are influenced by HIV. METHODS: As part of longstanding epidemiological studies in Karonga District, Malawi, a series of case control studies of TB and HIV were conducted from 1988 onwards. Data from these studies, from a total population survey, and from the Malawi national census have been used to reconstruct the changes in the TB epidemic in the area from 1988 to 2001, examining the role of HIV. RESULTS: The incidence of all confirmed TB, and of new smear-positive TB, in adults increased to peak in the late 1990s but appears to have decreased since. Two-thirds of cases are now HIV positive. The rise in incidence was greatest in the 30-44-year-old age group and was particularly marked for women, leading to a decrease in the male : female ratio for TB incidence from 1.3 to 0.8. The proportion of new smear-positive TB cases attributable to HIV increased from 17% in 1988-1990 to 57% in 2000-2001, but the estimated rate of smear-positive TB in the absence of HIV decreased from 0.78/1000 to 0.45/1000. CONCLUSIONS: Without HIV the incidence of smear-positive TB would have fallen in this population. Instead it has risen and is predominantly affecting young adults and women. There is some evidence that the HIV-associated TB epidemic may have passed its peak.     

Excess mortality and tuberculosis among individuals with prolonged cough: a population-based study from Vietnam.

SETTING: A demographic surveillance site in north-west Vietnam. OBJECTIVES: To compare notification rates of sputum smear-positive tuberculosis (TB) and mortality rates between the general population and individuals with prolonged cough. DESIGN: A cohort study of 559 prolonged cough cases in a total population of 35,832, observed over 2.5 years. Outcome measures were sputum smear-positive TB and death. RESULTS: The age-standardised smear-positive TB notification rate among cough cases (553/100,000 person-years [py], 95%CI 268-1143) was significantly higher than in the general population (50/100,000 py, 95%CI 43-57), with a relative risk of 11.06 (95%CI 8.28-14.77). Among those who had a chest X-ray suggestive of TB but negative sputum smears prior to the study start, the rate was 6542/100,000 py (95%CI 2906-12,511). The cough cohort had a 2.61 (95%CI 2.38-2.87) times higher risk of dying than the general population. CONCLUSIONS: Individuals with prolonged cough in this study run a significantly increased risk of developing infectious TB and of dying. We recommend further evaluations of improved follow-up systems aimed at identifying and treating sputum smear-negative TB cases before they convert to an infectious stage.     

Additional risk of developing TB for household members with a TB case at home at intake: a 15-year study.

OBJECTIVE: To assess the additional risk to household contacts from an infectious case of tuberculosis (TB) at home in a rural community in south India. METHODS: In all, 3506 contacts of smear-positive (S+C+) and 2910 contacts of smear-negative TB cases (S-C+) and 246 845 persons with no TB case at home were followed for 15 years, with a repeat survey every 2.5 years consisting of radiographic and sputum examination, selective follow-up of high-risk individuals and passive surveillance. If a case developed during follow-up, all household members were subsequently considered as contacts. Cox's proportional hazards model (multivariate) was employed to compare incidences. RESULTS: The annual incidence of culture-positive TB was respectively 526 and 271 per 100000 population for contacts of smear-positive and smear-negative patients, and 198/100000 in non-contacts. The adjusted hazard rate was 3.4 for contacts of smear-positive patients (95% CI 3.0-3.9) and 1.7 for contacts of smear-negative patients (95% CI 1.4-2.0) as compared to non-contacts. Of 3942 incident cases, 337 (8.5%) came from households with a TB case. CONCLUSION: Although family contacts had a significantly higher incidence, their contribution to total new caseload was meagre. Contact chemoprophylaxis as a public health measure would therefore have limited impact on community TB incidence.     

The growing burden of tuberculosis: global trends and interactions with the HIV epidemic

BACKGROUND: The increasing global burden of tuberculosis (TB) is linked to human immunodeficiency virus (HIV) infection. METHODS: We reviewed data from notifications of TB cases, cohort treatment outcomes, surveys of Mycobacterium tuberculosis infection, and HIV prevalence in patients with TB and other subgroups. Information was collated from published literature and databases held by the World Health Organization (WHO), the Joint United Nations Programme on HIV/Acquired Immunodeficiency Syndrome (UNAIDS), the US Census Bureau, and the US Centers for Disease Control and Prevention. RESULTS: There were an estimated 8.3 million (5th-95th centiles, 7.3-9.2 million) new TB cases in 2000 (137/100,000 population; range, 121/100,000-151/100,000). Tuberculosis incidence rates were highest in the WHO African Region (290/100,000 per year; range, 265/100,000-331/100,000), as was the annual rate of increase in the number of cases (6%). Nine percent (7%-12%) of all new TB cases in adults (aged 15-49 years) were attributable to HIV infection, but the proportion was much greater in the WHO African Region (31%) and some industrialized countries, notably the United States (26%). There were an estimated 1.8 million (5th-95th centiles, 1.6-2.2 million) deaths from TB, of which 12% (226 000) were attributable to HIV. Tuberculosis was the cause of 11% of all adult AIDS deaths. The prevalence of M tuberculosis-HIV coinfection in adults was 0.36% (11 million people). Coinfection prevalence rates equaled or exceeded 5% in 8 African countries. In South Africa alone there were 2 million coinfected adults. CONCLUSIONS: The HIV pandemic presents a massive challenge to global TB control. The prevention of HIV and TB, the extension of WHO DOTS programs, and a focused effort to control HIV-related TB in areas of high HIV prevalence are matters of great urgency.     

Fourteen-year trend of tuberculosis dynamics in the northwest of Turkey

BACKGROUND: The incidence of tuberculosis (TB) in different countries as estimated by the World Health Organization (WHO) vary from 23/100,000 and less in industrialized countries, 191/100,000 in Africa and 237/100,000 in South East Asia. OBJECTIVES: The aim of this study was to analyze the dynamics of TB in the northwest of Turkey, between 1988 and 2001. METHODS: All pulmonary TB cases reported to the National Tuberculosis Center by local TB dispensaries during 1988-2001 were analyzed. The number of new and relapsed TB cases were documented and classified according to age and type of TB (standard classification of TB patients according to disease type: pulmonary, new, smear positive; pulmonary, smear negative; relapse, and extrapulmonary). We recorded information about the prevalence of TB in different patient groups (patients with a contact history, patients who were detected in active community screening or passive case finding), TB trends in different age groups, type of TB, patients who had relapses, percentage of patients who were lost to follow-up. RESULTS: A total number of 288,996 patients were examined at Zonguldak Tuberculosis Dispensary between 1988 and 2001. Case notification rates of TB decreased over the study period. Respiratory TB was the most commonly encountered form of disease (>90%). The percentage of TB decreased in the 0- to 14-, 15- to 24-year-olds and increased in the 25- to 44- and 45- to 64-year-olds. CONCLUSION: Properly designed disease surveillance systems are critical for monitoring the TB trends so that each country can identify its own high-risk groups and target interventions to prevent, diagnose, and treat the disease.     

Analysis of factors related to the high incidence of tuberculosis in the city of Wakayama--analysis according to age groups, and sputum test results

Over the last 20 years, the decrease in the incidence of Tuberculosis (TB) in Japan has slowed down. As of 1999, the incidence rate was 34.6 per 100,000 population in Japan, which was higher than that of the other developed countries, and the incidence rate in the city of Wakayama, one of the prefectural capital cities in Japan, during the same period was 42.9 per 100,000 population. We investigated the causes of this high incidence rate of TB in Wakayama City according to the analysis by age groups and sputum test results when patients are newly registered. Comparing our data during the period from 1.1.1998 to 12.31.1999 with data during the same period in the whole country and the rest of Wakayama Pref., the following results were obtained. Observing by age-groups, the incidence of TB in Wakayama City as well as in the rest of Wakayama Pref. and in the whole country was highest in the age-group above 70 years of age, though the rate of Wakayama City was significantly higher (146.2 per 100,000 population) than that in the rest of Wakayama Pref. (98.5 per 100,000 population) and that in the whole country (90.3 per 100,000 population). Furthermore, the incidence rate of cases diagnosed as TB without bacteriological proof in Wakayama City (57.1 per 100,000 population) was significantly higher than that of the whole country (33.7 per 100,000 population). Therefore, we concluded that one of the causes of high incidence of TB in Wakayama City was due to inappropriate method of diagnosing TB. More extensive use of sputum examination and strict evaluation of cases without bacteriological proof are desirable to increase the accuracy of TB diagnosis in Wakayama City.     

What is the limit to case detection under the DOTS strategy for tuberculosis control?

In year 2000, the WHO DOTS strategy for tuberculosis (TB) control had been adopted by 148 out of 212 countries, but only 27% of all estimated sputum smear-positive patients were notified under DOTS in that year. Here we investigate the way in which gains in case detection under DOTS were made up until 2000 in an attempt to anticipate future progress towards the global target of 70% case detection. The analysis draws on annual reports of DOTS geographical coverage and case notifications, and focuses on the 22 high-burden countries (HBCs) that account for about 80% of new TB cases arising globally each year. Our principal observation is that, as TB programmes in the 22 HBCs have expanded geographically, the fraction of the estimated number of sputum smear-positive cases detected within designated DOTS areas has remained constant at 40-50% although there are significant differences between countries. This fraction is about the same as the percentage of all smear-positive cases notified annually to WHO via public health systems worldwide. The implication is that, unless the DOTS strategy can reach beyond traditional public health reporting systems, or unless these systems can be improved, case detection will not rise much above 40% in the 22 HBCs, or in the world as a whole, even when the geographical coverage of DOTS is nominally 100%. We estimate that, under full DOTS coverage, three-quarters of the undetected smear-positive cases will be living in India, China, Indonesia, Nigeria, Bangladesh and Pakistan. But case detection could also remain low in countries with smaller populations: in year 2000, over half of all smear-positive TB cases were living in 49 countries that detected less than 40% of cases within DOTS areas. Substantial efforts are therefore needed (a) to develop new case finding and management methods to bridge the gap between current and target case detection, and (b) to improve the accuracy of national estimates of TB incidence, above all by reinforcing and expanding routine surveillance.     

Evaluation of tuberculosis trends in Spain, 1991-1999.

SETTING: There are no reliable official data available on tuberculosis (TB) in Spain. OBJECTIVE: To ascertain the epidemiological trends of TB in Spain from 1991-1999. METHODS: In an annual survey conducted by the Tuberculosis and Respiratory Infections (TRI) Working Group of the Spanish Society of Pneumology and Thoracic Surgery (SEPAR), data on tuberculosis disease and infection were solicited from two information sources: 1) the public health services of the 17 Autonomous Regions (AR), and 2) 60 TRI members in different parts of Spain. RESULTS: TB incidence declined from 36.4/100,000 in 1991 to 26.7 in 1999 according to the AR (average annual decline 3.3%), and from 45.6 to 26.8 according to TRI members (annual decline 5.1%). A similar observation was made for smear-positive cases (AR annual decline: 3.0%; TRI: 5.6%). Tuberculosis infection at 6 years of age also decreased according to both information sources (AR: 0.87% in 1991 to 0.5% in 1998, annual decline 6%, and TRI members: 1.00% in 1991 and 0.9% in 1997, annual decline 4.2%). CONCLUSIONS: The observed rates of TB are higher than stated in official figures. In spite of the decreasing trend, observed declines are small and the current rates continue to be among the highest among industrialised countries.     

Increasing TB case detection through intensive referral of TB suspects by village doctors to county TB dispensaries.

OBJECTIVE: To explore new approaches to increase the detection of tuberculosis cases (TB). DESIGN: Thirty counties participated in the study. Patients with TB symptoms were surveyed and referred by trained village doctors to county dispensaries, designated township health centres or general hospitals for free sputum examination. TB patients and suspects notified by general hospitals were traced by TB staff if they defaulted during the transfer. RESULTS: A total of 12,091 new smear-positive TB cases were detected. The registration rate of new smear-positives increased from 36.2 per 100,000 population before the project to 49.9/100,000 after the project, and the case detection rate under the DOTS strategy reached 86%. Of 43,464 registered TB suspects, 15,363 (35.3%) were referred by village and hospital doctors. The referral rate increased significantly (P < 0.01). Of the 15,363 referred patients, 3870 were diagnosed as new smear-positive TB cases. Among three different microscopy centres, there was a statistically significant difference in the sputum examination rates of TB suspects and in the smear-positive rates among the suspects examined. The follow-up rate was 70.9%, but the follow-up success rate was only 33.1%. CONCLUSIONS: Intensive referral of patients with TB symptoms by village doctors to TB dispensaries is an effective way of increasing detection. At the same time, incentives are necessary for patients and village doctors.     

Gender disparity amongst TB suspects and new TB patients according to data recorded at the South African Institute of Medical Research laboratory for the Western Cape Region of South Africa.

OBJECTIVE: To describe the sex and age distribution of sputum submission and smear positivity in the Western Cape Province of South Africa. METHOD: Laboratory registers of the South African Institute of Medical Research were examined retrospectively for the year 1999. RESULTS: Male tuberculosis (TB) suspects outnumbered females by 1.45:1, whereas amongst confirmed TB cases the ratio was 2.08:1. The odds ratio (OR) for smear positivity amongst males and females was 1.544. The proportion of male sputum positives significantly exceeded the proportion of males in the general population, as measured by the 1996 census. Not only did the number of male TB suspects and confirmed cases exceed that of females in absolute terms, but the proportion of male suspects proving smear-positive exceeded that of females. The age by sex distribution of new smear-positive patients followed the trend reported in recent literature. CONCLUSION: The gendered incidence of tuberculosis identified from this census is consistent with that of other developing countries. However, the smaller proportion of female TB suspects proving smear-positive suggests a higher index of suspicion in females and/or longer delays prior to care seeking amongst males.     

Progress in global tuberculosis control 1995-1996, with emphasis on 22 high-incidence countries. Global Monitoring and Surveillance Project.

OBJECTIVE: To review global tuberculosis case notifications and treatment outcomes, and to assess progress in TB control 1995-1996, especially in the 22 countries that carry 80% of all incident cases. DESIGN: Compilation of case notifications; cohort analysis of treatment outcomes in DOTS and non-DOTS programmes. RESULTS: The 181 of 212 countries (85%) that reported data to WHO in 1997 covered 97% of the global population. They reported 3.81 million cases of tuberculosis, of which 1.29 million were smear-positive, representing case detection rates of approximately 39% and 51%, respectively. DOTS programmes diagnosed 67% of new pulmonary cases to be smear-positive (65% expected), compared with 30% in other control programmes. They evaluated a higher fraction of registered cases (94% vs 55%), achieved higher treatment success rates (78% vs 45%), and a higher fraction of patients was shown to be cured by smear conversion (72% vs 23%). Despite the apparent advantages of DOTS, only 12% of all estimated cases, and only 15% of smear-positive cases, were treated in such programmes. CONCLUSION: With the exceptions of Vietnam, Peru and Tanzania, none of the 22 highest-incidence countries achieved WHO targets for TB control. The slow progress is of greatest concern in 16 countries, including India, Indonesia, Nigeria and Pakistan.     

Tuberculosis in Spain: epidemiological pattern and clinical practice.

SETTING: Thirteen Autonomous Regions in Spain. OBJECTIVE: To study the incidence of all forms of tuberculosis (TB) and investigate clinical practice in TB. DESIGN: Cases of all forms of tuberculosis diagnosed in the study setting from May 1986 to April 1997 were identified though active search of different databases. Clinical and epidemiological information on cases was collected from clinical records or by interview with physicians. RESULTS: The overall incidence of all forms of tuberculosis was 38.5/100,000 and the incidence of smear-positive disease was 13.83/100,000. Most cases (97.1%) were Spanish nationals, with rates higher in men than in women (52.7/100,000 vs. 24.87/100,000) and in groups aged 25-34 and 75 years and over (61.35/100,000 and 59.35/100,000, respectively). Disseminated forms were frequent (6.6%), and the most common risk factor was human immunodeficiency virus (HIV) infection (17.7% of cases). Hospitalisation was common (71.6%). Microbiological confirmation of diagnosis was sought for 87.7% of the cases (91.8% of pulmonary vs. 75.5% of extra-pulmonary cases), and 65.2% were culture-positive (73.8% of pulmonary vs. 39.7% of extra-pulmonary cases). HIV-infected patients were treated in almost equal proportions with three or four drugs (49.7% and 48.2%, respectively), while HIV-negative cases or those whose HIV status was unknown were usually treated with three drugs. CONCLUSION: The epidemiological pattern of TB in Spain is different to other industrialised countries in the age distribution of cases and the proportions of foreigners and cases with HIV infection. Microbiological confirmation of diagnosis is more common in pulmonary than in extra-pulmonary disease, and treatment with four drugs more frequent in HIV-positive cases.     

2011年中国在校学生肺结核疫情分析

目的 研究2011年中国在校学生肺结核报告发病率及疫情特征。方法采用数据挖掘方法,由国家疾病监测信息报告管理系统获得全人群、学生肺结核报告发病例数数据,根据中国统计年鉴统计在校学生人数,两者结合共同计算全人群、学生肺结核报告发病率。由结核病管理信息系统获取全人群、学生登记肺结核患者人口学特征、诊断分类及预后数据。由国家突发公共卫生事件管理信息系统获取结核病突发事件报告信息。采用上述数据对比分析在校学生肺结核疫情特征。结果2011年全人群肺结核报告发病率为71.09/10万(953 275/1 340 909 996),在校学生肺结核报告发病率为20.16/10万(41 608/206 339 584)。山东省在校学生肺结核报告发病率最低,为10.54/10万（1508/14 300 995）,西藏的在校学生肺结核报告发病率最高,为66.24/10万（350/528 389）。2011年登记学生患者的涂阳比率为30.59%（12 193/39 853）,低于全人群患者涂阳比率的46.82%(423 830/905 344),差异有统计学意义（χ²＝3542.85,P<0.01）。学生初治涂阳患者2个月末痰菌转阴率（97.37%,11 310/11 616）及治愈率（95.56%,11 278/11 802）均高于全人群患者（93.83%,353 729/377 005;93.98%,353 238/375 859）,差异均有统计学意义（χ²值分别为247.70和50.79,P值均<0.01）。 结论 2011年中国在校学生肺结核报告发病率约为全人群报告发病率的1/3,学生登记涂阳肺结核患者比率低,而学生初治涂阳患者治愈率较高,学校结核病控制仍需进一步加强。     

Doubling of the tuberculosis incidence in Greenland over an 8-year period (1990-1997).

OBJECTIVE: To determine the trends in conventional and molecular epidemiology of tuberculosis (TB) in Greenland over an 8-year period. DESIGN: A nation-wide, retrospective, population-based study of all cases of TB reported to the National Health Division of Greenland from 1 January 1990 to 31 December 1997. An analysis of microbiology data including RFLP results. RESULTS: The annual incidence increased from 85/100,000 in 1990 to 172/100,000 in 1997; 335 (72%) of the cases were culture-positive. On average 58% of culture-positive cases were smear-positive, with an increase from 40% in 1990 to 69% in 1997. There was a significant increase in childhood TB from four cases in 1990 to 26 in 1997. RFLP analysis shows that 15% of the patients were infected with unique strains and 85% were infected with strains belonging to one of 20 clusters. There were four major clusters, comprising respectively 52, 34, 26 and 14 patients. CONCLUSION: There was a dramatic increase in TB cases in Greenland from 1990 to 1997. The increase is due to micro-epidemics in small isolated settlements, and affects primarily young adults and children. RFLP analysis confirms this observation and indicates confined, local transmission. In this context RFLP is not useful as the only parameter for monitoring recent transmission.