A prevalence survey for smear-positive tuberculosis in Thai prisons.

SETTINGS: Twenty-seven prisons in Thailand. OBJECTIVES: To measure the prevalence of smear-positive tuberculosis (TB) and to compare its detection using the World Health Organization (WHO) guidelines for prisons or the International Standards for Tuberculosis Care (ISTC) criteria. METHOD: Prisoners who were not on TB medications and who had not been treated for TB in the previous 6 months were enrolled in the survey. Prison nurses conducted a one-time mass screening using the WHO questionnaire, with follow-up sputum collection in TB suspects. RESULTS: Of 71594 prisoners, 22132 (30.9%) were identified as TB suspects, and 254 were confirmed by sputum smear, for a prevalence of 354.8/100000. Males were most likely to be diagnosed with TB disease (OR 2.6), as were those transferring in from another prison versus new prisoners (OR 3.0). The positive predictive value of the WHO criteria was 1.2%, and that of the ISTC standard was 5.9%. CONCLUSION: TB prevalence in this survey remained high. WHO guidelines, recognised as a standard, require health workers to question prisoners and measure height and weight. The ISTC standard, a single question about cough >or=2 weeks, is simple, may be asked by non-health personnel and may be a better alternative.     

Treatment outcome of tuberculosis patients under directly observed treatment in Addis Ababa,Ethiopia

BackgroundTuberculosis is one of the leading causes of mortality among infectious diseases worldwide. For effective tuberculosis control, it is a pre-requisite to detect the cases as early as possible, and to ensure that the tuberculosis patients complete their treatment and get cured. However, in many resource-constrained settings treatment outcome for tuberculosis has not been satisfactory.ObjectiveThe aim of the study was to assess the treatment outcome of tuberculosis patients and investigate the association of demographic and clinical factors with treatment success of patients enrolled in Directly Observed Treatment Short Course program in government owned health centers over the course of five consecutive years in Addis Ababa, Ethiopia.MethodsA register based historical cohort study covering the period of July 2004 to June 2009 was conducted to determine the treatment outcome of Directly Observed Treatment Short Course in government owned health centers in Addis Ababa. Sex and age of tuberculosis patients, health center at which the patient was treated, year of treatment, type of tuberculosis for which the patient was treated, type of treatment offered to the patient, follow-up status and documented treatment outcome were extracted from the Directly Observed Treatment Short Course clinics of three randomly selected health centers.ResultRecords of 6450 registered tuberculosis patients (n = 3147 males and 3433 females) were included in this document review. Of these patients 18.1% were reported as being cured, 64.6% were documented as treatment completed, 3.7% died during follow-up, 5.1% were reported as defaulters, 0.4% were documented as treatment failure and 8.2% were transferred out to another health institution. Treatment center and year of enrollment were significantly associated with treatment success.ConclusionYear of enrollment and treatment center were significantly associated with treatment success. Although the overall treatment success obtained in this study is in line with the World Health Organization (WHO) target, continuous follow-up of patients with frequent supportive supervision during the course of treatment, and further investigate the cause for the observed difference in treatment success across treatment centers are recommended.     

A survey of tuberculosis prevalence in Hanoi, Vietnam.

OBJECTIVE: To assess the prevalence of tuberculosis (TB) in Hanoi, Vietnam, in 2003/2004. METHODS: A random selection was carried out involving 11624 subjects from 20 communes within the city. RESULTS: On chest X-ray examination, 317 subjects (2.73%) showed abnormal lung opacity, of which 17 were sputum smear-positive, two concentrated smear-positive and three culture-positive, all with active TB. The prevalence of sputum smear-positive pulmonary TB was 146 per 100000 in persons aged >or=15 years (95%CI 65-228). CONCLUSION: This is the first large-scale assessment of the prevalence of TB in Hanoi. The prevalence rate was higher than expected, suggesting that a significant number of patients with active TB, particularly females, remain undiagnosed, thus representing a continuing potential source of transmission in the community.     

Mortality impact of AIDS in Addis Ababa,Ethiopia

OBJECTIVE: To measure the impact of HIV on mortality in Addis Ababa, Ethiopia. DESIGN: A retrospective review of burials at three cemeteries, 1987-2001 and a prospective surveillance of burials at all (n = 70) cemeteries, February-May, 2001. METHODS: The age, sex, and date of burial were recorded; in the absence of denominators, we compared the ratio of deaths of persons 25-49 versus 5-14 years of age per calendar year, using logistic regression, adjusting for sex and site. The age- and sex- specific mortality were calculated and compared with pre-HIV mortality in 1984. RESULTS: Of 17,519 deaths, retrospectively reviewed, complete data were available for 6342 (47%) females and 7269 (53%) males. During 1987-2001, the '25-49' versus '5-14' group all-cause mortality ratio increased by 8.5% per calendar year (P < 0.05). A total of 5101 deaths were recorded in the prospective surveillance. Crude mortality rates were 9.5/1000 per year (men) and 7.1/1000 per year (women). In comparison with 1984, 5.0-times as many men and 5.3-times as many women died in the age group 35-39 years. Attributing the increase in mortality in ages 15-60 to HIV in the period 1984-2001, Ethiopian men and women have a probability of 18.8 and 17.8%, respectively, of dying of HIV before age 60. CONCLUSION: Burials increased significantly among the '25-49', versus the '5-14' group, during the period 1987-2001. This trend, and a five-times higher mortality in 2001 than in 1984 in those aged 35-39 years demonstrate a severe impact of HIV on mortality. Continuing surveillance of burials is recommended.     

Sensitivity to anti-tuberculosis drugs in HIV-positive and -negative patients in Addis Ababa

A cross-sectional survey was conducted between 1 August and 31 December, 1998 in Addis Ababa, Ethiopia to determine the rate of primary drug resistance to anti-tuberculosis drugs and to investigate its possible association with HIV infection. Sputum culture, sensitivity to first-line anti-tuberculosis drugs and HIV testing were done for 236 sputum smear-positive pulmonary tuberculosis patients. Primary drug resistance level (single or multidrug resistance) had not changed significantly since 1994. Primary resistance occurred more often among HIV-positive than among HIV-negative patients. The association between drug resistance and HIV will have a serious impact in the control of tuberculosis because in recent years the prevalence of HIV has increased dramatically in Ethiopia. Therefore, further studies on drug resistance and HIV infection and the establishment of drug resistance surveillance are recommended.     

如何在患病率调查中确诊结核病患者

在患病率调查中确诊结核病（TB）患者是一个挑战,因为进行诊断的工作强度较大,并且由于患病率很低（通常不高于1200／10万人口）需要在大量人群中筛查。使用3种检验方法：调查问卷、胸片（CXR）和细菌学检验,细菌学检验包括痰涂片显微镜检和痰培养。这些方法可以应用在四个策略中以确定结核病患者。最敏感的策略是对每个符合条件的人应用所有的方法。敏感性仅次于上述的策略是对每个符合条件的人应用调查问卷、CXR和痰涂片镜检,收集有症状的、CXR异常的或涂片阳性者的痰液进行培养。如果实验室能力有限,可以采用问诊和CXR筛选出结核病高危人群,然后收集这些人的痰液进行涂片镜检和培养。如果CXR和培养都不能应用,可以收集所有符合条件的人的痰标本,应用一种增强的显微镜检方法,如荧光显微镜检的方法进行检测。理想状态下,病例定义是基于问诊、CXR和细菌学检验的综合结果。     

How to identify tuberculosis cases in a prevalence survey

The identification of pulmonary tuberculosis (TB) cases in a prevalence survey is a challenge, as diagnostic methods are labour-intensive and large numbers of individuals need to be screened because the prevalence rate is low (almost never greater than 1,200 per 100,000 population). Three testing methods are used: questionnaires, chest radiography (CXR) and bacteriological tests, including sputum smear microscopy and culture. These methods can be applied in four strategies to identify cases. The most sensitive strategy is to apply all methods to each eligible individual. The next most sensitive option is to apply the questionnaire, CXR and sputum smear microscopy to each eligible individual and obtain sputum for culture from those individuals with symptoms, abnormalities on the CXR or a positive smear. If laboratory capacity is limited, screening using symptom enquiry and CXR can be used to select those individuals at highest risk of TB. These individuals are then requested to submit sputum for smear microscopy and culture. If neither CXR nor culture is available, sputum samples may be collected from all eligible individuals and examined by an enhanced microscopy method such as fluorescence microscopy. Case definitions are ideally based on the combined results of symptom enquiry, CXR and bacteriology.     

Follow-up tuberculosis prevalence survey of Transkei

After 5 years a follow-up prevalence survey was conducted in Transkei on a randomly selected sample of the rural population. The parameters investigated were bacteriological prevalence of tubercle bacilli in sputum, radiological prevalence of chest abnormalities associated with tuberculosis in adults, and hypersensitivity to tuberculin in children. Bacteriological positivity was 2.1% on smear microscopy and 4.3% on culture. Radiological evidence of tuberculosis was demonstrable in 12.5% of subjects, of whom 8.7% were considered active and 3.8% inactive. The mean prevalence of tuberculin positivity according to the Mantoux test was 30.1%. An annual risk of infection of 4% was calculated, showing a continuous decrease of 5% per year on the 7% risk of infection encountered in 1972. Compared with the first survey, a general reduction in prevalence of tuberculosis is evident.     

河南省涂阳肺结核合并糖尿病情况调查分析

目的了解河南省涂阳肺结核合并糖尿病流行情况、X线特点、耐药情况与治疗转归,以供肺结核临床诊治和控制工作参考。方法在第二轮结核病耐药监测时同步进行血糖检测。所入选的涂阳肺结核病人在抗结核治疗前空腹服用葡萄糖75g后2h抽静脉血查血糖。胸部X线片特征由专家读片组共同读片分析并记录。结果调查入选902例涂阳肺结核病人,糖尿病患者检出率为12.6%,糖耐量降低者检出率为14.9%,二者合计为27.5%;40岁以上年龄组检出率显著高于40岁以下年龄组。合并糖尿病的涂阳肺结核耐药率为45.6%,显著高于血糖正常组(35.2%)及糖耐量降低组(32.8%)(P<0.05);血糖异常的肺结核病人病灶分布于中下肺野及对侧、双侧播散者较多,渗出性病灶、干酪性病灶、合并胸腔积液在肺结核合并糖尿病的病人中较血糖正常者多(分别为93%,87.7%、14.0%)。血糖异常涂阳肺结核空洞发生率较高(95.9%)。强化期痰菌转阴率、疗程结束治愈率血糖正常组分别为88.1%、91.7%,血糖异常组分别为77.4%、86.3%,(P<0.05)。结论糖尿病及糖耐量异常者在涂阳肺结核病人中的检出率明显高于一般人群;涂阳肺结核者合并糖尿病者X线表现有一定特点,有助于及时发现,诊治;在涂阳肺结核病合并糖尿病、糖耐量降低者中,血糖异常知晓率较低;并糖尿病的复治涂阳肺结核耐药率高,血糖异常可影响痰菌及时阴转和治愈率,不利于结核病流行的控制,值得重视。     

河南省涂阳肺结核合并糖尿病情况调查分析

目的了解河南省涂阳肺结核合并糖尿病流行情况、X线特点、耐药情况与治疗转归，以供肺结核临床诊治和控制工作参考。方法在第二轮结核病耐药监测时同步进行血糖检测。所入选的涂阳肺结核病人在抗结核治疗前空腹服用葡萄糖75g后2h抽静脉血查血糖。胸部X线片特征由专家读片组共同读片分析并记录。结果调查入选902例涂阳肺结核病人，糖尿病患者检出率为12．6％，糖耐量降低者检出率为14．9％，二者合计为27．5％；40岁以上年龄组检出率显著高于40岁以下年龄组。合并糖尿病的涂阳肺结核耐药率为45．6％，显著高于血糖正常组（35．2％）及糖耐量降低组（32．8％）（P〈0．05）；血糖异常的肺结核病人病灶分布于中下肺野及对侧、双侧播散者较多，渗出性病灶、干酪性病灶、合并胸腔积液在肺结核合并糖尿病的病人中较血糖正常者多（分别为93％，87．7％、14．0％）。血糖异常涂阳肺结核空洞发生率较高（95．9％）。强化期痰菌转阴率、疗程结束治愈率血糖正常组分别为88．1％、91．7％，血糖异常组分别为77．4％、86．3％，（P〈0．05）。结论糖尿病及糖耐量异常者在涂阳肺结核病人中的检出率明显高于一般人群；涂阳肺结核者合并糖尿病者x线表现有一定特点，有助于及时发现，诊治；在涂阳肺结核病合并糖尿病、糖耐量降低者中，血糖异常知晓率较低；并糖尿病的复治涂阳肺结核耐药率高，血糖异常可影响痰菌及时阴转和治愈率，不利于结核病流行的控制，值得重视。     

The rapid village survey in tuberculosis control

Setting: Khon Kaen Province, North-East Thailand.Objective: To develop a rapid and cheap method of surveying a population cluster (a village) to establish the prevalence of sputum-positive tuberculosis.Design: Based on previous experience a standardized ‘rapid village survey’ method was designed and tested. In this method a survey team of health workers is constituted and trained. Before and at the beginning of a visit to a village the population receives information about tuberculosis, and only individuals with chest symptoms are invited to report voluntarily to the survey team for examination. Active tracing of a previously compiled ‘list of suspects and contacts’ complements the identification of cases. The number of community members to be examined is thus much lower. A cluster sample of the provincial population was made (20 730 people in 40 villages). The population in each village was surveyed first by the Rapid Village Survey method, then, 1 week later, by the conventional method of examining every individual registered in each village.Results: In the rapid village survey 14 cases of sputum-positive tuberculosis were detected and in the conventional survey 15 cases.Conclusion: The rapid method produces results comparable to the survey of the total sample population for less than half of the cost.     

Assessment of Diabetes Education in the Teaching Hospital,Addis Ababa,Ethiopia

With the aim of assessing continuing diabetes education and obtaining baseline information, we have evaluated the knowledge of 139 randomly selected diabetic patients from the Diabetes Clinic of Tikur Anbessa Teaching Hospital, Addis Ababa, Ethiopia. Seventy-five Type 1 (insulin-dependent) and 64 Type 2 (non-insulin-dependent) diabetic patients, with a mean age of 36 ± 14 (± SD) (range 15–78, median 36) years, and mean duration of known diabetes 6.3 ± 5.5 (range 1–30, median 5) years participated in the study. Knowledge was assessed by a questionnaire which examined three principal areas: general knowledge on diabetes mellitus, diet plus self care, and chronic complications. Twenty-eight (20.1 %), did not attend any and 59 (42.5 %) attended the diabetes education programme more than once. The Adjusted Percentage Score (APSCORE) was 69 ± 1.4 (SEM). Type 1 diabetic patients had a significantly higher score (p < 0.001) for overall knowledge when compared to Type 2 patients. In both groups the knowledge on chronic complications was very poor when compared to the other areas (p < 0.001). No sex difference in knowledge was seen. Higher school and diabetes education attendance had a significant influence on the knowledge of diabetes. However, better knowledge about diabetes was not associated with better glycaemic control as measured by the fasting blood glucose concentration. The wide difference in knowledge, the low rate of attendance at diabetes education sessions, and the very low awareness about chronic complications is very worrying. To achieve the intended aim the diabetes education programme needs to be revised.     

Disclosure of diagnosis by parents and caregivers to children infected with HIV: prevalence associated factors and perceived barriers in Addis Ababa, Ethiopia

Vertical transmission of HIV from infected mothers to children is a common phenomenon. After the introduction of highly active antiretroviral treatment (HAART), most children live longer than before. Recently, HAART has become widely available to children living in sub-Saharan African countries, and this makes disclosure of HIV status an important issue. We conducted a cross-sectional survey involving 172 parents/caregivers of HIV-infected school-age children who had follow-up at the Pediatric Infectious Disease Clinic of the Yekatit 12 Hospital, Addis Ababa. Only 16.3% of HIV-infected schoolchildren knew their diagnosis. The child's age was the main predictor of disclosure (OR: -0.25; 95% CI: -0.35, -0.09; p<0.05). The main reason for nondisclosure was fear of negative emotional consequences for the child. More than half of the parent/caregivers agreed that they need to tell the children their diagnosis, but 86% reported that they needed health care providers to help them at the event. The low rate of disclosure found in this study shows the need for awareness creation and training of health professionals, and this should be supported by appropriate guidelines to be followed by health professionals working in pediatric ART clinics. Caregivers need to be provided with the necessary knowledge and skills on how to look after children who know their HIV status.     

Under-diagnosis of smear-positive pulmonary tuberculosis in Nairobi, Kenya.

SETTING: Nairobi City Council Chest Clinic, Nairobi, Kenya. OBJECTIVE: To determine if under-reading of sputum smears is a contributing factor in the disproportionate increase in smear-negative tuberculosis in Nairobi, Kenya. METHODOLOGY: Between October 1997 and November 1998, patients fulfilling the local programme definition of smear-negative presumed pulmonary tuberculosis were enrolled in the study. Two further sputum specimens were collected for examination in a research laboratory by fluorescence microscopy. RESULTS: Of 163 adult subjects enrolled, 55% were seropositive for the human immunodeficiency virus type 1 (HIV-1). One hundred subjects had had two pre-study sputum smears assessed before recruitment and produced two further sputum specimens for re-examination in the research laboratory; of these 19 (19%) were sputum smear-positive on re-examination and a further seven (7%) became smear-positive on second re-examination. CONCLUSIONS: Of those patients with smear-negative presumed pulmonary tuberculosis by the local programme definition, 26% were smear-positive when reexamined carefully with two repeat sputum smears. This suggests that the high rates of smear-negative tuberculosis being seen may in part be due to under-reading. This is probably as a result of the overwhelming burden of tuberculosis leading to over rapid and inaccurate sputum examination. Retraining of existing technicians and training of more technicians is likely to reduce underreading and increase the yield of smear-positive tuberculosis. This finding also stresses the need for regular quality assurance.     

Gender differences in tuberculosis: a prevalence survey done in Bangladesh.

SETTING: Bangladesh national tuberculosis control programme districts supported by the Damien Foundation (population 18 million). OBJECTIVE: To determine whether the observed gender difference is epidemiologically true or whether it is due to accessibility barriers for women. DESIGN: Two-stage random sampling population survey. People were interviewed by teams composed of one male and one female volunteer about the presence of symptoms suggestive of tuberculosis. One early morning sputum specimen of all thus identified tuberculosis suspects was examined by Ziehl-Neelsen technique. RESULTS: A total of 266189 people were surveyed, among whom 223 936 (84.1%) could be interviewed. This led to the identification of 7001 tuberculosis suspects (2406 females and 4595 males) and 64 confirmed TB cases (16 females and 48 males). The female/male ratio (0.33:1) of cases found during the survey was not higher than that observed through routine diagnosis (0.42:1). The routine case-notification rate of sputum-positive cases during 2000 was about twice the rate observed during the survey (44.3 vs. 24.0 per 100 000 population). CONCLUSIONS: The gender difference observed in routine tuberculosis diagnosis is real, and is not due to lesser accessibility of women to the health services. The routine notification rate compares favourably with the detection of previously unknown cases found during the survey.     

Gender differences in relation to sputum submission and smear-positive pulmonary tuberculosis in Malawi.

OBJECTIVE: To examine gender differences in sputum submission and sputum smear positivity. METHODS: Laboratory registers in all diagnostic units in eight districts in Malawi were examined for the years 1995 and 1996. RESULTS: During a 12-month period (averaged between 1995 and 1996), 26,624 new TB suspects submitted sputum samples, 3282 of which (12.3%) were smear-positive. Significantly more males submitted sputum (52%) compared with females (48%), and significantly more males (53%) were smear-positive compared with females (47%, P < 0.05). Rates of sputum submission per 100,000 adults were also significantly higher for males (1203) than females (1032). CONCLUSION: In Malawi, fewer females are submitting sputum samples and are being diagnosed with smear-positive TB compared with males.     

The occurrence and driver characteristics associated with motor vehicle injuries in Addis Ababa, Ethiopia.

Ethiopian documentation of the occurrence and determinants of motor vehicle related morbidity and mortality is sparse. The purpose of this investigation was to determine the incidence of hospital treated motor vehicle injuries (MVI) in Addis Ababa and driver characteristics associated with involvement in a MVI. The study was conducted over a 12-week period in the autumn of 1988. Over 91% of MVI involved pedestrians. The overall MVI incidence density rate was 279.4 per 100,000 person years and the mortality rate was 17.6 per 100,000 population per year. Road accident injury and fatality rates were 946 and 59.5 respectively per 10,000 registered vehicles. Overall years of person life lost was 595 per 100,000 person-years exposure. Significantly increased odds of exposure among drivers inflicting a MVI were found for younger age, fewer years driving experience, male gender, and those driving newer, government owned, and mass transit vehicles.     

Efficiency of serial smear examinations in excluding sputum smear-positive tuberculosis.

SETTING: This study determined the number of slides required to identify one additional case of sputum smear-positive tuberculosis (TB) from the third smear. The study hypothesis was that not more than 100 and 75 slides, respectively, in Mongolia and Zimbabwe, need to be examined to find one additional case of TB with a third serial diagnostic sputum smear examination. METHODS: In a retrospective, record-based study, data were abstracted from TB laboratory registers from all 31 laboratories in Mongolia and 23 randomly selected laboratories in Zimbabwe using a uniform EpiData collection instrument. RESULTS: A total of 52,909 records of examinees were available. In Mongolia, of 15 103 suspects, 1717 (11.4%) were positive. Of these, 0.7% were positive for the first time on the third smear examination. In Zimbabwe, of 25 693 suspects, 3452 (13.4%) were positive and 4.5% were positive only on the third smear examination. The expected number of slides required to detect one additional case on the third examination was 1153.3 for Mongolia and 132.6 for Zimbabwe. CONCLUSIONS: The requirement of routine examination of three serial smears before declaring a suspect as a 'non-case' (of sputum smear-positive TB) will need to be reviewed in both Mongolia and Zimbabwe.     

Association of prevalence of tuberculin reactions with closeness of contact among household contacts of new smear-positive pulmonary tuberculosis patients.

OBJECTIVES: Among household contacts of newly diagnosed smear-positive pulmonary tuberculosis (TB) patients, to examine the association of apparent tuberculosis transmission with the closeness and duration of contact. METHODS: Household contacts of newly diagnosed patients with smear-positive pulmonary TB were identified, as well as a healthy population sample. Household contacts were categorized into three groups based on closeness, regularity, and duration of contact with index cases. All subjects underwent tuberculin testing. RESULTS: Among the household contacts, 47 of 112 (42%) of very close/intimate contacts had positive tuberculin tests, compared to 121 of 356 (34%) close/ regular contacts and 23 of 178 (13%) not close/sporadic contacts and 55 of 355 (16%) of a healthy population sample. CONCLUSIONS: Even among household contacts of smear-positive pulmonary TB patients, there were major differences in the proximity and duration of contact which were strongly associated with differences in the prevalence of positive tuberculin reactions.