Congenital rubella syndrome in Haiti (Short communication).

OBJECTIVE: To determine if there is an unrecognized problem of congenital rubella syndrome (CRS) in Haiti, a country without a national rubella immunization program. METHODS: During March 2001 and June 2001, screening physicals were conducted on approximately 80 orphans at three orphanages in Haiti that accept disabled children. Children were classified as probable CRS cases based on established clinical criteria. Photo documentation of findings was obtained whenever possible. RESULTS: Six children met the criteria for probable CRS. Using data from surrounding Caribbean countries and from the United States of America prior to rubella immunization, we estimated that there are between 163 and 440 new cases of CRS per year in Haiti. CONCLUSIONS: CRS exists in Haiti, but its presence is generally unrecognized. A national rubella immunization policy should be considered.     

Rapid assessment of tuberculosis in a large prison system--Botswana, 2002

Prisons are settings in which tuberculosis (TB) transmission occurs, and TB rates in prisons are often five to 10 times higher than national rates. Data on the prevalence of TB in prisons in Africa are limited; however, studies from Malawi, Ivory Coast, and Tanzania that used active screening found TB rates > or = 10 times higher than national rates. During 1989-2001, TB rates in Botswana increased threefold, from 199 cases per 100,000 population to 620 (Botswana National TB Program, unpublished data, 2002). This increase has been associated with the human immunodeficiency virus (HIV) epidemic. In Botswana, prisoners are not screened routinely for TB. To determine the prevalence of TB and drug-resistant TB in the Botswana prison system and to improve future screening for TB among prisoners and guards, CDC, in collaboration with the Botswana Ministry of Health and the Division of Prisons and Rehabilitation, screened prisoners and guards at four prisons during April-May 2002. This report summarizes the results of the survey, which indicate a high point prevalence of TB among prisoners in Botswana of 3,797 cases per 100,000 population and support the need for improved screening.     

2021年重庆市新生筛查结核病结果分析

目的 分析重庆市不同医疗机构开展新生结核病筛查效果的异同,为学校结核病新生筛查工作提供参考。方法 通过《重庆市新生结核病筛查调查表》和《重庆市统计年鉴》收集2021年重庆市秋季入学的各教育阶段新生结核病筛查资料和学生人口数据,分析学生活动性肺结核患者检出率及结核菌素纯蛋白衍生物(purified protein derivative tuberculin, PPD)强阳性率,采用SPSS 25.0进行描述性分析和χ²检验。结果 2021年重庆市新生结核病筛查798 135人,筛查率为42.36%,其中高中(61.48%)、初中(54.93%)筛查率较高。共发现151人活动性肺结核患者,高中(34.82/10万)、高等教育(28.59/10万)及寄宿制初中(11.83/10万)检出率较高。学前教育及小学新生197 469人,主要由其他医疗机构(41.44%)开展筛查工作。非寄宿制初中新生有14 587人开展了结核症状筛查,以其他医疗机构筛查为主。寄宿制初中新生有194 457人开展了PPD筛查,不同类型医疗机构患者检出率差异有统计学意义(P=0.002),不同类型医...     

Expanding tuberculosis case detection by screening household contacts

OBJECTIVES: Tuberculosis (TB) case detection remains low in many countries, compromising the efficacy of TB control efforts. Current global TB control policy emphasizes case finding through sputum smear microscopy for patients who self-report to primary health centers. Our objective was to assess the feasibility and yield of a simple active case finding strategy in a high incidence population in northern Lima, Peru. METHODS: We implemented this pilot strategy in one health center's catchment area. Health workers visited household contacts of new TB case subjects to identify symptomatic individuals and collect sputum for screening. Neighboring households were screened in the same manner. Secondary analyses measured risk of TB by (1) sputum smear status of the index case subject, (2) compliance with testing, and (3) risk factors for disease detected through active contact tracing in contrast to self-report. RESULTS: The TB prevalence detected through combined active and passive case finding among 1,094 household contacts was 0.91% (914 per 100,000), much higher than with passive case finding alone (0.18%; 183 per 100,000; p=0.02). Among 2,258 neighbors, the combined strategy detected a TB prevalence of 0.22% (221 per 100,000) in contrast to 0.08% (80 per 100,000) detected through passive case finding alone (p=0.25). Risk factors for being diagnosed through active case finding in contrast with self-report included age >55 years (odds ratio [OR]=5.5; 95% confidence interval [CI] 1.2, 22.8) and female gender (OR=3.9; 95% CI 0.99, 22.3). CONCLUSIONS: Risk of active TB among symptomatic household contacts of active case subjects in this community is very high. Results suggest that contact tracing in such settings may be a powerful means of improving case detection rates for active TB disease.     

Screening for tuberculosis among 2381 household contacts of sputum-smear-positive cases in The Gambia

Contact investigation is a key component of tuberculosis (TB) control in developed, but not developing, countries. We aimed to measure the prevalence of TB among household contacts of sputum-smear-positive TB cases in The Gambia and to assess the sensitivity of an enzyme-linked immunospot (ELISPOT) assay in this regard. Household contacts of adult smear-positive TB patients were assessed by questionnaire, purified protein derivative (PPD) skin test, ELISPOT assay, physical examination, chest X-ray and sputum/gastric aspirate. Thirty-three TB cases were identified from 2174 of 2381 contacts of 317 adult smear-positive pulmonary TB patients, giving a prevalence of 1518/100000. The cases identified tended to have milder disease than those passively detected. The sensitivity of ESAT-6/CFP-10 ELISPOT test as a screening test for TB disease was estimated as 71%. Fifty-six per cent of contacts with a PPD skin test result >or=10mm induration had detectable responses to ESAT-6/CFP-10 by ELISPOT; 11% with a negative PPD skin test (<10mm) had a positive ESAT-6/CFP-10 response. Active screening for TB among contacts of TB patients may have a role in TB control in The Gambia. These individuals are a high-risk group, and the disease identified is less advanced than that found through passive case detection. An ELISPOT assay was relatively insensitive as a screening test for TB.     

西安市小学入学新生结核病筛查结果分析

目的 了解西安市小学入学新生结核感染及患病情况,为儿童及学校结核病防治工作提供科学依据。方法 分别选择西安市市区和乡镇共7所小学,共筛查小学入学新生2 982名,采用结核菌素(PPD)试验结合胸部X线检查方法。结果 全部新生结核感染率为2.1%(64/2 982);不同性别感染率差异无统计学意义(χ²=3.848,P>0.05)。不同地区感染率差异有统计学意义(χ²=8.896,P<0.05)。PPD试验强阳性者行胸部X线检查,共检出结核患者2例,患病率67/10⁵。结论 重视在校学生结核病筛查,是儿童结核病防治的有效措施。乡镇学生的结核感染率高于市区学生。     

Evaluation of immigrant tuberculosis screening in industrialized countries

In industrialized countries, tuberculosis (TB) cases are concentrated among immigrants and driven by reactivation of imported latent TB infection (LTBI). We examined mechanisms used to screen immigrants for TB and LTBI by sending an anonymous, 18-point questionnaire to 31 member countries of the Organisation for Economic Co-operation and Development. Twenty-nine (93.5%) of 31 responded; 25 (86.2%) screened immigrants for active TB. Fewer countries (16/29, 55.2%) screened for LTBI. Marked variations were observed in targeted populations for age (range <5 years of age to all age groups) and TB incidence in countries of origin of immigrants (>20 cases/100,000 population to >500 cases/100,000). LTBI screening was conducted in 11/16 countries by using the tuberculin skin test. Six countries used interferon-γ release assays, primarily to confirm positive tuberculin skin test results. Industrialized countries performed LTBI screening infrequently and policies varied widely. There is an urgent need to define the cost-effectiveness of LTBI screening strategies for immigrants.     

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.     

Improved Detection of Tuberculosis and Multidrug-Resistant Tuberculosis among Tibetan Refugees,India

The incidence of tuberculosis (TB) among Tibetan refugees in India is 431 cases/100,000 persons, compared with 181 cases/100,000 persons overall in India in 2010. More than half of TB cases in these refugees occur among students, monks, and nuns in congregate settings. We sought to increase TB case detection rates for this population through active case finding and rapid molecular diagnostics. We screened 27,714 persons for symptoms of TB and tested 3,830 symptomatic persons by using an algorithm incorporating chest radiography, sputum smear microscopy, culture, and a rapid diagnostic test; 96 (2.5%) cases of TB were detected (prevalence 346 cases/100,000 persons). Of these cases, 5% were multidrug-resistant TB. Use of the rapid diagnostic test and active case finding enabled rapid detection of undiagnosed TB cases in congregate living settings, which would not have otherwise been identified. The burden of TB in the Tibetan exile population in India is extremely high and requires urgent attention.     

New measurable indicator for tuberculosis case detection

The World Health Organization's goal for tuberculosis (TB) control is to detect 70% of new, smear-positive TB cases and cure 85% of these cases. The case detection rate is the number of reported cases per 100,000 persons per year divided by the estimated incidence rate per 100,000 per year. TB incidence is uncertain and not measured but estimated; therefore, the case detection rate is uncertain. This article proposes a new indicator to assess case detection: the patient diagnostic rate. The patient diagnostic rate is the rate at which prevalent cases are detected by control programs and can be measured as the number of reported cases per 100,000 persons per year divided by the prevalence per 100,000. Prevalence can be measured directly through national prevalence surveys. Conducting prevalence surveys at 5- to 10-year intervals would allow countries with high rates of disease to determine their case detection performance by using the patient diagnostic rate and determine the effect of control measures.     

Transmission of Mycobacterium tuberculosis in a California State Prison, 1991.

OBJECTIVES: An investigation was conducted to determine whether ongoing transmission of Mycobacterium tuberculosis was occurring in a California state prison. METHOD: Prison pharmacy records were used to identify cases of active tuberculosis (TB). RESULTS: Ten of the 18 cases of active TB treated at the facility during 1991 were diagnosed at the prison that same year (an incidence of 184 per 100,000). Three inmates were infectious for a total of 7 months while imprisoned. The prevalence of TB skin test-positivity among inmates was 30%, and the incidence of new infection attributable to incarceration was 5.9 per 100 inmates per year. CONCLUSIONS: Transmission of M. tuberculosis may be occurring in the California prison system.     

Contact tracing and population screening for tuberculosis--who should be assessed?

BACKGROUND: The aim of the study was to investigate the relative effectiveness of four strategies in detecting and preventing tuberculosis: contact tracing of smear-positive pulmonary disease, of smear-negative pulmonary disease and of non-pulmonary disease, and screening new entrants. METHODS: An analysis of patient records and a TB database was carried out for an NHS Trust-based tuberculosis service in a socio-economically deprived area. Subjects were contacts of all patients treated for TB between 1997 and 1999. New entrants were screened in 1999. Outcomes measured were numbers of cases of active tuberculosis detected and numbers of those screened given chemoprophylaxis. RESULTS: A total of 643 contacts of 227 cases of active TB were seen, and 322 new entrants to the United Kingdom. The highest proportion of contacts requiring full treatment or chemoprophylaxis were contacts of smear-positive index cases (33 out of 263 contacts; 12.5 per cent). Tracing contacts of those with smear-negative pulmonary tuberculosis (12 out of 156; 7.7 per cent) and non-pulmonary disease (14 out of 277; 6.2 per cent) was significantly more effective in identifying individuals requiring intervention (full treatment or chemoprophylaxis) than routine screening of new entrants (10 out of 322; 3.1 per cent). CONCLUSIONS: Screening for TB of new entrants to the United Kingdom is part of the national programme for control and prevention of TB, whereas tracing contacts of those with smear-negative and non-pulmonary disease is not. This study demonstrates that, in our population, the contact-tracing strategy is more effective than new entrant screening. It is not likely that the contacts have caught their disease from the index case, but rather that in high-incidence areas such as ours such tracing selects extended families or communities at particularly high risk.     

Evaluation of identifying tuberculosis infection and disease in a rural institutionalized population

ContextAlthough the overall prevalence of tuberculosis (TB) in the United States is declining, correctional facilities continue to encounter a higher prevalence of this disease. Despite mandatory reporting laws for active TB, data for latent TB infection (LTBI) remains sketchy because reporting it is not required.PurposeInvestigation of the period prevalence of LTBI in a rural Ohio regional jail compared with other populations in the region to determine the need and adequacy of the screening program.MethodsData collected on inmates was compared with data collected on hospital employees within the same geographic region.FindingsBetween January 2006 and July 2007, staff at the jail tested 1274 inmates for TB using the Mantoux purified protein derivative (PPD) method. Ten inmates (6 in 2006 and 4 in 2007) tested positive. All 10 cases were followed with a negative chest radiograph, leading to the diagnosis of LTBI. The overall incidence for the jail for LTBI was 0.8%, with 0% active cases. However, 85 inmates (6.7% of the population) were released before a PPD interpretation could be completed. In the comparative population, 651 hospital employees were tested for TB. Of these, 32 employees tested positive (LTBI prevalence of 4.9%). There were no cases of active TB reported.ConclusionThe prevalence of LTBI in a rural jail (0.8%) is lower than the comparative sample population at a local hospital (4.9%). The rapid release of inmates (6.7%) indicates that TB data is incomplete and that potential cases of LTBI could have been unreported because of missed opportunity for interpretation of skin tests.     

Cost effectiveness analysis of school based Mantoux screening for TB infection

OBJECTIVE: To assess the cost-effectiveness of adding school based Mantoux screening programs to the New South Wales current TB prevention strategy. METHOD: A decision analysis model compared the costs and consequences of screening strategies against the current no-screen strategy. Costs associated with screening and with treating future cases of TB were considered. Consequences considered were deaths and adult cases of TB prevented. The study was based on data from prevalence surveys conducted in 1992 and 1994 in Central and South Western Sydney, New South Wales. Screening strategies considered were screening all or only overseas born (OSB) 6 year olds and all or only OSB 14 year olds in school settings. RESULTS: Screening 14 year olds prevented more deaths and adult cases of TB than screening 6 year olds for a similar cost. For both age groups targeted screening of OSB children was more cost-effective than screening all children. Targeted screening of 14 year olds--the most cost effective option--cost $17,956 (costs and benefits discounted at 5%) per adult case prevented, equivalent to approximately $130,000 per life year saved. The cost-effectiveness ratios decline substantially if lower discount rates and less conservative assumptions are applied. CONCLUSION: Targeted screening was more cost effective than screening all children, however, there are ethical implications of targeting a group based on their origin of birth. IMPLICATIONS: As prevention and control of TB continues to be a high priority for NSW, the implications of a school based screening program should be seriously considered.     

Tuberculosis in South-East Asian Refugees after Resettlement-Can Prevention Be Improved by Better Policy and Practice?

Objective.This study aimed to determine whether incident cases of tuberculosis (TB) in a cohort of South-East Asian refugees followed for 5 years after resettlement were potentially preventible and whether prevention of TB was optimal in a state refugee TB screening program in Victoria, Australia.Design.A retrospective cohort study of 1,101 refugees from Laos, Cambodia, and Vietnam screened for TB in the 6-month period from July 1989 to January 1990 was conducted. Incident cases of TB were identified by matching each refugee with the TB notification database for 5 years from the date of initial screening. Preventability was assessed for incident cases by reviewing medical records. Screening guidelines and practice were reviewed.Results.The main outcome was the preventability of cases of active tuberculosis that developed in the study population in the first 5 years after resettlement. The incidence of active TB was 363/100,000 during the first year and 109/100,000/year during the first 5 years. Five of six incident cases were assessed aspotentiallypreventable, which if prevented would have resulted in an annual incidence of 18/100,000 over the first 5 years. Use of a more sensitive skin test definition of infection would have made an additional 245 refugees eligible for prevention and potentially prevented an additional 25 cases of TB over a lifetime.Conclusions.There is a high incidence of tuberculosis among SE Asian refugees, particularly in the first year after resettlement. A large proportion of TB may be preventable. Improvement in case prevention may be possible with updated guidelines and better implementation of screening policy.     

Do women with tuberculosis have a lower likelihood of getting diagnosed? Prevalence and case detection of sputum smear positive pulmonary TB, a population-based study from Vietnam

OBJECTIVE: The aim was to estimate the gender-specific prevalence of tuberculosis (TB) through screening. A further aim was to calculate case detection within the Vietnamese National TB program. STUDY DESIGN AND SETTING: A population-based survey of 35,832 adults was performed within an existing sociodemographic longitudinal study in Bavi district, northern Vietnam. Cases were identified by a screening question about prolonged cough and further diagnosed with sputum examination and a chest X-ray. RESULTS: The estimated prevalence of pulmonary TB among men was 90/100,000 (95% CI 45-135/100,000) and among women 110/100,000 (95% CI 63-157/100,000). Case detection in the district was estimated to 39% (95% CI 20-76%) among men and 12% (95% CI 6-26%) among women. CONCLUSION: TB prevalence was similar among men and women. Case detection among men and women was significantly lower than the reported national case detection of 80%, and there was a significant underdetection of female cases. These findings warrant actions, and emphasize the need to perform similar studies in different contexts.     

Implementation and effect of intensified case finding on diagnosis of tuberculosis in a large urban HIV clinic in Uganda: a retrospective cohort study

ABSTRACT: BACKGROUND: Increased detection of tuberculosis (TB) using intensified or active case finding (ICF) is one of the cornerstones of the Stop TB Strategy, and contrasts with passive case finding (PCF) which relies on self-reported symptoms. There is no clear guidance on implementation strategies. We implemented ICF in addition to ongoing PCF in our large urban HIV clinic in July 2010 using a twice-daily announcement screen method by a trained peer educator, asking waiting patients to self-refer to a trained peer supporter for screening of TB symptoms. We sought to determine the associated effect on TB case detection. METHODS: Suspects were investigated by sputum smear, chest X-ray and ultrasound, if indicated. Routinely collected clinical and laboratory data were merged with the ICF register and TB clinic data for patients attending the clinic in 2010. We compared the yield of TB cases (defined as the prevalence of newly diagnosed TB cases in the screened population), the type of TB diagnosed and the total cost per TB case identified (in United States Dollars [USD]) for the period before and after ICF implementation. RESULTS: Of the 20,456 patients who visited the clinic in 2010, 614 were identified as TB suspects, 220 pre-ICF and 394 post-ICF (229 via PCF and 165 via ICF). The proportion diagnosed with TB dropped from 66% to 48% (60% in suspects identified through PCF and 31% through ICF). During the post-ICF period, TB suspects identified through ICF compared to PCF identification were more likely to be female, older, on ART and to have been enrolled in HIV care for a longer duration. The yield of combined PCF and ICF screening was 1.4% pre-ICF and 1.7% post-ICF with a cost per TB case identified of 12.29 USD and 21.80 USD, respectively. CONCLUSIONS: Implementation of ICF in a large HIV clinic yielded more TB suspects and cases, but substantially increased costs and was unable to capture the majority of TB suspects who were referred for diagnosis by clinicians through PCF. The overall yield of TB cases in a mature HIV clinic was low, although targeted screening of those recently enrolled in care may increase the yield.     

Detecting Mycobacterium tuberculosis Infection in Children Migrating to Australia

In 2015, Australia updated premigration screening for tuberculosis (TB) disease in children 2–10 years of age to include testing for infection with Mycobacterium tuberculosis and enable detection of latent TB infection (LTBI). We analyzed TB screening results in children <15 years of age during November 2015–June 2017. We found 45,060 child applicants were tested with interferon-gamma release assay (IGRA) (57.7% of tests) or tuberculin skin test (TST) (42.3% of tests). A total of 21 cases of TB were diagnosed: 4 without IGRA or TST, 10 with positive IGRA or TST, and 7 with negative results. LTBI was detected in 3.3% (1,473/44,709) of children, for 30 applicants screened per LTBI case detected. LTBI-associated factors included increasing age, TB contact, origin from a higher TB prevalence region, and testing by TST. Detection of TB and LTBI benefit children, but the updated screening program’s effect on TB in Australia is likely to be limited.     

Decline of Tuberculosis Burden in Vietnam Measured by Consecutive National Surveys, 2007–2017

Vietnam, a high tuberculosis (TB) burden country, conducted national TB prevalence surveys in 2007 and 2017. In both surveys participants were screened by using a questionnaire and chest radiograph; sputum samples were then collected to test for Mycobacterium tuberculosis by smear microscopy and Löwenstein-Jensen culture. Culture-positive, smear-positive, and smear-negative TB cases were defined by laboratory results, and the prevalence of tuberculosis was compared between the 2 surveys. The results showed prevalence of culture-positive TB decreased by 37% (95% CI 11.5%–55.4%), from 199 (95% CI 160–248) cases/100,000 adults in 2007 to 125 (95% CI 98–159) cases/100,000 adults in 2017. Prevalence of smear-positive TB dropped by 53% (95% CI 27.0%–69.7%), from 99 (95% CI 78–125) cases/100,000 adults to 46 (95% CI 32–68) cases/100,000 adults; smear-negative TB showed no substantial decrease. Replacing microscopy with molecular methods for primary diagnostics might enhance diagnosis of pulmonary TB cases and further lower TB burden.     

Using cost and health impacts to prioritize the targeted testing of tuberculosis in the United States

PURPOSE: Evaluation improves efficiency and effectiveness. Current U.S. tuberculosis (TB) control policies emphasize the treatment of latent TB infection (LTBI). However, this policy, if not targeted, may be inefficient. We determined the efficiency of a state-law mandated TB screening program and a non state-law mandated one in terms of cost, morbidity, treatment, and disease averted. METHODS: We evaluated two publicly funded metropolitan TB prevention and control programs through retrospective analyses and modeling. Main outcomes measured were TB incidence and prevalence, TB cases averted, and cost. RESULTS: A non state-law mandated TB program for homeless persons in Tarrant County screened 4.5 persons to identify one with LTBI and 82 persons to identify one with TB. A state-law mandated TB program for jail inmates screened 109 persons to identify one with LTBI and 3274 persons to identify one with TB. The number of patients with LTBI treated to prevent one TB case was 12.1 and 15.3 for the homeless and jail inmate TB programs, respectively. Treatment of LTBI by the homeless and jail inmate TB screening programs will avert 11.9 and 7.9 TB cases at a cost of 14,350 US dollars and 34,761 US dollars per TB case, respectively. CONCLUSIONS: Mandated TB screening programs should be risk-based, not population-based. Non mandated targeted testing for TB in congregate settings for the homeless was more efficient than state-law mandated targeted testing for TB among jailed inmates.