Public health requirements for rapid progress in global health

Effective public health interventions can save hundreds of millions of lives in developing countries, as well as create broad social and economic benefits. Unfortunately, public health approaches and solutions applied in developed countries are often assumed to be inappropriate or unattainable in developing countries. This has sometimes forestalled effective interventions in parts of the world where they are most needed, despite conditions that now facilitate lasting solutions to both long-standing and emerging global public health problems. Core public health functions are similar regardless of a country's income level. Although some resource-intensive approaches from industrialised nations are inappropriate in less developed countries, many basic public health measures achieved decades ago in developed countries are urgently needed, highly appropriate, extremely cost-effective and eminently attainable in developing countries today. About half of the disease burden in low and middle-income countries is now from non-communicable diseases, but non-communicable disease epidemics that will otherwise increase rapidly in the developing world can be avoided or reversed. Progress of public health in developing countries is possible, but will require sufficient funding and human resources; improved physical plant and information systems; effective programme implementation and regulatory capacity; and, most importantly, political will at the highest levels of government.

Lessons from tuberculosis control for public health

Tuberculosis (TB) control in many ways exemplifies evidence-based public health practice, rigorously implemented, with appropriate emphasis on the central importance of political support for success. With more than 30 million patients treated in the past decade, TB control has important implications for managing both communicable and non-communicable diseases. Simple diagnostic tests, meticulously proven standardized treatment regimens with assured drug supply, supportive case management and a superb information system that tracks the progress of every patient, all facilitate effective program implementation. TB control shows that public health programs, including those that require long-term treatment in the primary care system, can be effective in poor countries; however, TB rates are heavily influenced by the social, environmental and epidemiologic context, emphasizing that treatment is not enough and that socio-economic factors may be more important determinants of epidemiologic trends than treatment programs. TB control is effective when it combines two essential components: a practical, implementable, proven technical package, and political commitment. Political commitment is also essential to implement other interventions that can improve health, including healthier air, water and food, as well as programs to prevent or reduce tobacco smoking, cardiovascular disease, cancer, obesity and other growing public health problems. By implementing evidence-based practices, ensuring operational excellence, using information systems that facilitate accountability and evaluation, and obtaining and maintaining political support, we can address the public health challenges of the twenty-first century.

Rapid decline in prevalence of pulmonary tuberculosis after DOTS implementation in a rural area of South India

SETTING

Tiruvallur District in Tamilnadu, South India, where the World Health Organization-recommended DOTS strategy was implemented as a tuberculosis (TB) control measure in 1999.

OBJECTIVE

To assess the epidemiological impact of the DOTS strategy on the prevalence of pulmonary tuberculosis (PTB).

DESIGN

Surveys of PTB were undertaken on representative population samples aged > or =15 years (n = 83000-90000), before and at 2.5 and 5 years after the implementation of the DOTS strategy. The prevalence of PTB (smear-positive/culture-positive) was estimated.

RESULTS

TB prevalence declined by about 50% in 5 years, from 609 to 311 per 100000 population for culture-positive TB and from 326 to 169/100000 for smear-positive TB. The annual rate of decline was 12.6% (95%CI 11.2-14.0) for culture-positive TB and 12.3% (95%CI 8.6-15.8) for smear-positive TB. The decline was similar at all ages and for both sexes.

CONCLUSION

With an efficient case detection programme and the DOTS strategy, it is feasible to bring about a substantial reduction in the burden of TB in the community.

Ensuring accountability: the contribution of the cohort review method to tuberculosis control in New York City

SETTING

In 1993, the New York City (NYC) Bureau of Tuberculosis Control developed the cohort review process as a quality assurance method to track and improve patient outcomes.

METHODS

The Bureau Director reviews every tuberculosis (TB) case quarterly in a multi-disciplinary staff meeting. In 2004 we also began collecting details on issues identified at cohort review to quantify how this process directly impacts TB control efforts.

RESULTS

From 1992 to 2004, NYC TB cases decreased by 72.7% and treatment success rates significantly increased by 26.7%. Implementing the cohort review was key to improving case management, thus leading to these results. For the 1039 patients in 2004, 596 issues were identified among 424 patients; 55.0% were incorrect, unclear or unknown patient information, 13.8% were treatment issues, 12.4% were case management issues and 10.6% were incomplete contact investigations. Most (76.5%) issues were addressed within 30 days of the cohort reviews.

CONCLUSION

A systematic review of every TB case improves the quality of patient information, enhances patient treatment and ensures accountability at all levels of the TB control program.

Active community surveillance of the impact of different tuberculosis control measures, Tiruvallur, South India, 1968-2001

BACKGROUND

Tuberculosis is curable, but community surveys documenting epidemiological impact of the WHO-recommended DOTS strategy on tuberculosis prevalence have not been published. We used active community surveillance to compare the impact of DOTS with earlier programmes.

METHODS

We conducted tuberculosis disease surveys using random cluster sampling of a rural population in South India approximately every 2.5 years from 1968 to 1986, using radiography as a screening tool for sputum examination. In 1999, DOTS was implemented in the area. Prevalence surveys using radiography and symptom screening were conducted at the start of DOTS implementation and after 2.5 years.

RESULTS

From 1968 to 1999, culture-positive and smear-positive tuberculosis declined by 2.3 and 2.5% per annum compared with 11.9 and 5.6% after DOTS implementation. The 2.5 year period of DOTS implementation accounted for one-fourth of the decline in prevalence of culture-positive tuberculosis over 33 years. Multivariate analysis showed that prevalence of culture-positive tuberculosis decreased substantially (10.0% per annum, 95% CI: 2.8-16.6%) owing to DOTS after only slight declines related to temporal trends (2.1% annual decline, 95% CI: 1.1-3.2%) and short-course chemotherapy (1.5% annual decline, 95% CI: -9.7% to 11.5%). Under DOTS, the proportion of total cases identified through clinical care increased from 81 to 92%.

CONCLUSIONS

Following DOTS implementation, prevalence of culture-positive tuberculosis decreased rapidly following a gradual decline for the previous 30 years. In the absence of a large HIV epidemic and with relatively low levels of rifampicin resistance, DOTS was associated with rapid reduction of tuberculosis prevalence.

Extrapulmonary tuberculosis among foreign-born patients, New York City, 1995 to 1996

In New York City both the proportion of total tuberculosis cases that are extrapulmonary and the proportion of total tuberculosis cases that are foreign-born have increased since 1992. We examined the association of region of birth and site of extrapulmonary tuberculosis among 3982 persons confirmed to have tuberculosis in 1995 or 1996, while controlling for age, gender, culture result, reporting facility, and HIV status. Patients born in the Middle East (odds ratio; 3.9, p = .0001), India (odds ratio = 2.5, p = .0007), other Asian countries (excluding China, Japan and countries of the former Soviet Union) (odds ratio = 2.7, p = .0001), sub-Saharan Africa (odds ratio = 2.6, p = .0001), and the Caribbean (odds ratio = 2.0, p = .0001) were more likely to have extrapulmonary disease than patients born in the United States. The proportion of total cases with extrapulmonary involvement is likely to increase in areas where the foreign-born comprise a growing proportion of all cases of tuberculosis. Although reasons for regional differences in tuberculosis disease site are not known, these findings should alert health care providers to maintain a high index of suspicion for extrapulmonary tuberculosis among some foreign-born groups.

Value of dual testing for identifying tuberculous infection

SETTING

A rural community in Chingleput district in Tamil Nadu state in south India.

OBJECTIVE

To determine the value of dual testing with PPD-S and PPD-B for identifying subjects with a tuberculous infection.

DESIGN

About 240,000 subjects in rural south India, all of whom were tested initially with PPD-S and PPD-B, were followed up for 15 years, mainly by total population survey once in every 212 years. The incidence of culture-positive tuberculosis was estimated using life-table technique.

RESULTS

Among 17,530 subjects with an intermediate reaction (8-11 mm) to PPD-S at intake, 285 with an induration to PPD-S exceeding the induration to PPD-B by at least 2mm, had a significantly higher incidence of culture-positive tuberculosis than the remaining (154 and 93 per 100,000), and similarly 481 who had an induration of <10mm to PPD-B compared to those with >or=10 mm (131 and 93 per 100,000). These subjects may be regarded as having a tuberculous infection. Infection with non-tuberculous mycobacteria conferred protection of about 30% against the development of tuberculosis over a 15-year period.

CONCLUSION

In subjects with an intermediate reaction (8-11 mm) to PPD-S, dual testing with PPD-B enabled identification of those with a tuberculous infection. Most of the reactions were due to non-tuberculous mycobacteria.

Improved tuberculosis case detection through public-private partnership and laboratory-based surveillance, Kannur District, Kerala, India, 2001-2002

BACKGROUND

Efforts to intensify global tuberculosis (TB) control are limited by difficulties in coordinating with private doctors. More than half of Indian TB patients may initially consult a private provider, but many are neither diagnosed accurately nor treated effectively. We established and evaluated a public-private partnership based on surveillance of TB detected in private laboratories and use of standardised directly observed treatment regimens.

METHODS

In one district, the governmental TB control programme offered training in microscopy to all large private sector laboratories, and educated private physicians on the importance of microscopy for TB diagnosis. We reviewed records from participating private laboratories and all publicly diagnosed patients.

RESULTS

Of 2328 pulmonary TB patients registered from July 2001 to December 2002, 404 (17%) were detected in the private sector. The annual new AFB-positive case notification rate increased by 21%, from 27.8/100,000 in 2000 to 33.5/100,000 in 2002. Surveillance at private laboratories found an additional 260 nonregistered AFB-positive patients.

CONCLUSIONS

This public-private partnership substantially increased TB case detection and established a sustainable framework for private sector involvement in TB control. In the setting of a strong public sector programme, the combination of active surveillance of private laboratories along with physician sensitisation is a promising approach to improve TB case detection.

Comparison of cough of 2 and 3 weeks to improve detection of smear-positive tuberculosis cases among out-patients in India

SETTING

Governmental health facilities in six districts of India.

OBJECTIVE

To estimate the prevalence of cough and to compare the detection of smear-positive tuberculosis (TB) among out-patients with cough of > or =2 or > or =3 weeks.

DESIGN

Trained health workers questioned each out-patient for presence of cough. Those with cough > or =2 weeks underwent sputum microscopy.

RESULTS

Of 55561 out-patients interviewed, 2210 (4%) had cough > or =2 weeks, of whom 267 had sputum-positive TB, compared to 182/1370 with cough > or =3 weeks. The 31% who did not spontaneously complain of cough were less likely to be sputum-positive than those who did (45/680 [7%] vs. 222/1530 [15%], P < 0.001), but they accounted for 45/267 smear-positive cases. Using cough > or =2 weeks as the screening criterion, the estimated number of smears performed per day at each primary and secondary health care facility was respectively 8 and 19, compared to 5 and 12 using cough > or =3 weeks.

CONCLUSION

The detection of smear-positive TB cases can be substantially improved by actively eliciting history of cough from all out-patients, and by changing the screening criterion for performing sputum microscopy among out-patients from cough > or =3 weeks to > or =2 weeks. Before implementing this change nationally, its programmatic feasibility should be assessed.

A survey of tuberculosis hospitals in India

SETTING

Hospitals with beds for tuberculosis (TB) in India.

OBJECTIVES

To assess diagnostic and treatment practices at institutions offering secondary or tertiary level care for TB patients, and to determine the resources being used at these institutions.

DESIGN

Countrywide cross-sectional survey of TB hospitals using a mailed semi-structured questionnaire sent to all 105 hospitals with 100 or more beds and to all State Directorate Health Services.

RESULTS

The 94 hospitals that returned the questionnaire had 15773 TB beds, one third of the total TB beds in the country. Nearly 1 million patients sought treatment in the TB hospitals and one third were diagnosed with TB; the ratio of smear-positive to smear-negative patients was 1:2.7. Sixty-four per cent of hospitals prescribed unobserved rifampicin in the continuation phase, and 56% of sputum smear-positive patients were hospitalised. The annual expenditure for the TB hospitals was more than the total annual budget for the TB control programme of the country.

CONCLUSIONS

In view of the high number of patients seen and the suboptimal practices observed, urgent steps should be taken to ensure implementation of correct diagnostic and treatment policies in hospitals with TB beds.

Gender disparities in tuberculosis: report from a rural DOTS programme in south India

SETTING

Tiruvallur District, south India.

OBJECTIVES

To examine gender differences in tuberculosis among adults aged >14 years with respect to infection and disease prevalence, health care service access, care seeking behaviour, diagnostic delay, convenience of directly observed treatment (DOT), stigma and treatment adherence.

METHODS

Data were collected from 1) community survey, 2) self-referred out-patients seeking care at governmental primary health institutions (PHIs), 3) tuberculosis suspects referred for sputum microscopy at PHIs, and 4) tuberculosis patients notified under DOTS. Community survey results were compared with those for patients notified at PHIs.

RESULTS

In the community, 66% of males and 57% of females had tuberculosis infection. The prevalence of smear-positive tuberculosis was 568 and 87/100,000, respectively, among males and females. Fewer males than females attended PHIs (68 men for every 100 women). Females constituted 13% of all smear-positive patients detected in the community survey, and 20% of those detected at PHIs (P < 0.05). The probability of notification decreased significantly with age among both males and females. Significantly more females than males felt inhibited discussing their illness with family (21% vs. 14%) and needed to be accompanied for DOT (11% vs. 6%). Males had twice the risk of treatment default than females (19% vs. 8%; P < 0.01).

CONCLUSIONS

Despite facing greater stigma and inconvenience, women were more likely than men to access health services, be notified under DOTS and adhere to treatment. Men and elderly patients need additional support to access diagnostic and DOT services.

Reduced detection by Ziehl-Neelsen method of acid-fast bacilli in sputum samples preserved in cetylpyridinium chloride solution

SETTING

Twelve health facilities implementing the DOTS strategy, and the Tuberculosis Research Centre (TRC), Chennai, India.

OBJECTIVE

To determine the detection rates using Ziehl-Neelsen (ZN) and auramine-phenol to stain acid-fast bacilli (AFB) in sputum samples stored in cetylpyridinium chloride (CPC) solution.

METHODS

Two smears were prepared from each of 988 sputum samples collected in CPC and randomly allocated, one to ZN and the other to auramine-phenol staining. All samples were processed for culture of Mycobacterium tuberculosis.

RESULTS

A significantly higher proportion of samples were negative using the ZN method compared to the auramine-phenol method (74.5% vs. 61.8%, McNamara's paired chi2 test; P < 0.001). Among 377 samples that were positive using auramine-phenol, 44% were negative using ZN. There were more culture-positive, smear-negative samples in ZN (52.7%) than in auramine-phenol (30%); the difference attained statistical significance (McNemar's paired chi2 test; P < 0.00004). Using ZN, of the 104 smears made immediately after collection, 52 were positive for AFB, of which only 35 (67.3%) were positive after storage in CPC; the reduction in the number of positive smears attained statistical significance (McNemar's paired chi2 test; P = 0.004).

CONCLUSION

Detection of AFB in sputum samples preserved in CPC is significantly reduced using ZN staining.

A baseline survey of the prevalence of tuberculosis in a community in south India at the commencement of a DOTS programme

OBJECTIVE

To determine the baseline prevalence of culture-positive and smear-positive tuberculosis and the annual risk of tuberculous infection (ARTI) in a community in south India where DOTS is being implemented.

METHODS

Using cluster sampling, 50 rural panchayats (villages) and three urban units in Tiruvallur district were selected randomly. All adults aged > or = 15 years underwent symptom and radiographic examination, and those with abnormal shadows and/or chest symptoms had sputum smear and culture examination. In another cluster sample of 73 villages and three urban units, all children aged < 10 years were tuberculin tested.

RESULTS

The prevalence of culture-positive and smear-positive tuberculosis was respectively 605 and 323/100,000. Both increased appreciably with age, and were substantially higher in males than in females at all ages; the overall male:female ratio was 5.5 for culture-positive and 6.5 for smear-positive tuberculosis. The ARTI in children aged under 10 years was 1.6%, and was unaffected by sex. Over three decades there was an overall decline of 1.8% per annum in the prevalence of culture-positive and 2.1% for smear-positive tuberculosis.

CONCLUSION

Tuberculosis is a major problem in this rural community in south India, with a prevalence of 605/100,000 for culture-positive tuberculosis and 323/100,000 for smear-positive tuberculosis.

Impact of national consultants on successful expansion of effective tuberculosis control in India

SETTING

India, during a period of rapid expansion of DOTS services. DOTS expansion has been slow in many countries.

OBJECTIVE

To document use of consultants to expand DOTS effectively.

DESIGN

Staff were contracted to monitor DOTS expansion and implementation. To estimate the impact of these staff, we compared areas with and without consultants, and individual areas before and after consultants were assigned. Consultants were preferentially assigned to the more difficult areas; the temporary absence of consultants reflected non-availability of candidates.

RESULTS

Areas with consultants met pre-defined criteria and began DOTS service delivery faster (median 9 vs. 18 months of preparation) than areas without consultants. Rates of sputum conversion (87% vs. 83%, P < 0.001) and treatment success (83% vs. 78%, P < 0.001) were significantly higher in areas with consultants present.

CONCLUSION

Assignment of consultants resulted in much more rapid implementation of the DOTS strategy, and better quality performance. Continued effective performance in these areas will rely on many factors, but the need for consultants appears to be decreasing, suggesting that they have provided sustainable improvements. The effectiveness of local consultants may have important implications for efforts to scale up public health interventions for tuberculosis, malaria, AIDS and other diseases in developing countries.

Are community surveys to detect tuberculosis in high prevalence areas useful? Results of a comparative study from Tiruvallur District, South India

BACKGROUND

In Tiruvallur District, South India, tuberculosis cases are detected at health facilities (HF) as part of a DOTS programme, and by screening adults through community survey (CS) as part of ongoing epidemiological research.

OBJECTIVE

To compare socio-demographic, clinical and bacteriological characteristics and treatment outcomes of all patients detected at HF with those of all patients detected by CS during a 12-month period.

RESULTS

Of 32,663 adults surveyed, 100 had smear-positive and 116 had smear-negative tuberculosis; of 65 smear-positive patients who began treatment, 44 were cured. Compared to HF patients, CS patients were significantly more likely to be older (AOR = 1.9), male (AOR = 2.7), non-literate (AOR = 1.7), and living in poor quality housing (AOR = 2.0), and were less likely to have cough >3 weeks (AOR = 3.4) or smear-positive tuberculosis (AOR = 4.2). Of 61 new smear-positive CS patients, 40 reported chest symptoms; of these, 32 (80%) had already consulted a health-care provider, but remained undiagnosed.

CONCLUSIONS

The community survey was of little value in tuberculosis case detection even in this high-prevalence setting. Patients identified by the survey were less symptomatic and less infectious, and less than half were cured. Diagnostic services should be made more accessible to the elderly, the non-literate and men.

Risk factors associated with default, failure and death among tuberculosis patients treated in a DOTS programme in Tiruvallur District, South India, 2000

OBJECTIVE

To identify risk factors associated with default, failure and death among tuberculosis patients treated in a newly implemented DOTS programme in South India.

DESIGN

Analysis of all patients registered from May 1999 through April 2000. A community survey for active tuberculosis was underway in the area; patients identified in the community survey were also treated in this programme.

RESULTS

In all, 676 patients were registered during the period of the study. Among new smear-positive patients (n = 295), 74% were cured, 17% defaulted, 5% died and 4% failed treatment. In multivariate analysis (n = 676), higher default rates were associated with irregular treatment (adjusted odds ratio [AOR] 4.3; 95%CI 2.5-7.4), being male (AOR 3.4; 95%CI 1.5-8.2), history of previous treatment (AOR 2.8; 95%CI 1.6-4.9), alcoholism (AOR 2.2; 95%CI 1.3-3.6), and diagnosis by community survey (AOR 2.1; 95%CI 1.2-3.6). Patients with multidrug-resistant tuberculosis (MDR-TB) were more likely to fail treatment (33% vs. 3%; P < 0.001). More than half of the patients receiving Category II treatment who remained sputum-positive after 3 or 4 months of treatment had MDR-TB, and a large proportion of these patients failed treatment. Higher death rates were independently associated with weight <35 kg (AOR 3.8; 95%CI 1.9-7.8) and history of previous treatment (AOR 3.3; 95%CI 1.5-7.0).

CONCLUSIONS

During this first year of DOTS implementation with sub-optimal performance, high rates of default and death were responsible for low cure rates. Male patients and those with alcoholism were at increased risk of default, as were patients identified by community survey. To prevent default, directly observed treatment should be made more convenient for patients. To reduce mortality, the possible role of nutritional interventions should be explored among underweight patients.

Washing of new microscopic glass slides in dichromate solution does not influence sputum AFB smear results

SETTING

Microscopy centres in Tiruvallur District, Tamil Nadu, India, implementing DOTS.

OBJECTIVE

To know whether washing new glass slides in dichromate solution is essential for effective sputum acid-fast bacilli microscopy.

METHODS

Two direct smears were prepared from each of 1750 sputum samples. One was made on dichromate solution-cleaned new glass slides and the other was made on unwashed new glass slides. The smears were blinded and examined.

RESULTS

Of the 1750 specimens, 13.5% and 13.08% were positive for AFB using washed and unwashed slides, respectively (P = 0.12). The concordance between these two (including one grade above and one below) was 98.7%.

CONCLUSION

Washing of new glass slides in dichromate solution is not essential for AFB microscopy.

Public-private partnership in tuberculosis control: experience in Hyderabad, India

SETTING

Hyderabad, India.

OBJECTIVE

To determine whether private practitioners and the government can collaborate with a nongovernmental intermediary to implement DOTS effectively.

DESIGN

A non-profit hospital provided DOTS services to a population of 100000 for 3 years, then expanded coverage to 500000 in October 1998. A hospital physician visited all private practitioners, encouraged them to refer patients, and gave feedback on each patient referred. After diagnosis, patients received directly observed treatment free of charge at the trust hospital or at 30 conveniently located small hospitals operated by local private practitioners. No financial incentives were used to encourage physicians to refer patients or to provide treatment observation. Diagnosis, treatment, and case and outcome definitions were performed as per DOTS policies; medicines and laboratory reagents were provided by the government.

RESULTS

All 244 allopathic and 114 non-allopathic physicians practising in the area agreed to participate; 59% referred at least one patient. Of 2244 persons referred, 969 (43%) had tuberculosis. Physicians had obtained chest radiographs on 80% of patients before referral for sputum microscopy. The detection rate increased from 50 to 200/100000 over the first 2-3 years of the project, and has increased gradually since expansion; 90% of new smear-positive patients and 77% of re-treatment patients were successfully treated. Compared with those treated at a neighbouring government DOTS centre, patients in this project paid less for diagnosis ($5 vs. $20) and treatment ($1 vs. $11), largely due to lower transport costs.

CONCLUSIONS

Collaborative efforts between private practitioners and the government can achieve moderate-high rates of case detection and high rates of treatment success. Public-private services appeared to be more convenient to patients, who paid less for care and were less likely to miss work in order to participate in DOTS. Clearly defined roles and expectations and frequent communication are essential to success. An institution such as a non-profit hospital can serve as an effective intermediary between the government DOTS programme and private practitioners.

TB prevention in HIV clinics in New York City

SETTING

Ten hospital-based human immunodeficiency virus (HIV) clinics in New York City.

OBJECTIVE

To evaluate tuberculosis (TB) prevention in HIV clinics based on the prevalence and incidence of TB and the efficacy of preventive therapy with isoniazid (INH).

DESIGN

The medical records of 2393 HIV-infected patients with a first clinic visit in 1995 were reviewed retrospectively. Deaths and TB cases through December 1997 were ascertained through a match with the TB and AIDS registries.

RESULTS

At first visit, 92 patients (4%) had a history of TB, 98 (4%) were being treated for TB, and six (<1%) were diagnosed with TB. During follow-up, 23 cases were diagnosed, an incidence of 0.53 per 100 person-years (py) (95%CI 0.34-0.77). Among 439 tuberculin skin test (TST) positive patients, the incidence of TB/100 py was 1.63 (95%CI 0.27-5.02) in patients with no INH, 1.28 (95%CI 0.40-2.98) in patients with <12 months of INH, and 1.06 (95%CI 0.38-2.28) in patients with 12 months of INH. The incidence/100 py was 0.0 (95%CI 0.0-0.78) in TST-negative patients and 0.37 (95%CI 0.09-0.95) in anergic patients. The relative risk of TB was 0.65 (95%CI 0.14-4.56) in TST-positive patients with 12 months of INH (vs. none).

CONCLUSIONS

The benefits of TB prevention efforts in these HIV clinics from 1995 to 1997 were limited because most TB occurred before the first clinic visit. Methods for reaching HIV-infected patients earlier should be identified.

Trends in the prevalence and incidence of tuberculosis in south India

OBJECTIVE

To study trends in the prevalence and incidence of tuberculosis in south India.

METHODS

In 1968-1970, about 100,000 subjects were surveyed for tuberculosis and followed thereafter for 15 years, mainly by repeat survey once every 2.5 years. New entrants were inducted at every repeat survey. Radiographic examination of subjects aged 5 years or more and sputum smear and culture examinations of those with an abnormal shadow were undertaken; tuberculin tests were done initially on all, and at 4, 10 and 15 years in selected samples of those aged 1-9 years.

RESULTS

The prevalence of culture-positive tuberculosis decreased by 1.4% per annum to 694/100,000, while that of smear-positive tuberculosis showed no significant decrease from 457/100,000. The annual incidence of culture-positive tuberculosis decreased by 4.3%/annum to 189/100,000 and that of smear-positive tuberculosis decreased by 2.3%/annum to 113/100,000. Decreases in incidence occurred exclusively in those with abnormal radiographic findings suggestive of tuberculosis at the start of the period. The annual risk of tuberculosis infection (ARTI) was initially 2%, and showed no sign of decline over the period.

CONCLUSION

The prevalence of tuberculosis and ARTI showed little or no decrease over the 15-year period. A significant decrease in incidence occurred, but exclusively in those with abnormal radiograph suggestive of tuberculosis at the start of the period.

The status and prospects of tuberculosis control in India

SETTING

India, where much of the global strategy for tuberculosis control was established, but where, every year, there are an estimated 2 million cases of tuberculosis.

OBJECTIVE

To describe the policies, initial results, and lessons learned from implementation of a Revised National Tuberculosis Control Programme using the principles of DOTS (Directly Observed Treatment, Short-course).

DESIGN

A Revised National Tuberculosis Control Programme (RNTCP) was designed and implemented starting in 1993. With funding from the Government of India, State Governments, the World Bank and bilateral donors, regular supply of drugs and logistics was ensured. Persons with chest symptoms who attend health facilities are referred to microscopy centres for diagnosis. Diagnosed cases are categorized as per World Health Organization guidelines, and treatment is given by direct observation. Systematic recording and cohort reporting is done.

RESULTS

From October 1993 through mid-1999, 146,012 patients were put on treatment in the programme. The quality of diagnosis was improved, with the ratio of smear-positive to smear-negative patients being maintained at 1:1. Case detection rates varied greatly between project sites and correlated with the percentage of patients who were smear-positive among those examined for diagnosis, suggesting heterogeneous disease rates. Treatment success was achieved in 81% of new smear-positive patients, 82% of new smear-negative patients, 89% of patients with extra-pulmonary tuberculosis, and 70% of re-treatment patients.

CONCLUSION

The RNTCP has successfully treated approximately 80% of patients in 20 districts of 15 states of India. Treatment success rates are more than double and death rates are less than a seventh those of the previous programme. Starting in late 1998, the programme began to scale up and now covers more than 130 million people. Maintaining the quality of implementation during the expansion phase is the next challenge.

Rates and risk factors for discontinuation of rifampicin

SETTING

All patients with culture-confirmed, rifampin-susceptible Mycobacterium tuberculosis diagnosed during a 20-month period in New York City, who were started on a rifampin-containing regimen and received > or =60 days of treatment.

OBJECTIVE

To identify rates of and reasons for rifampin discontinuation.

DESIGN

Retrospective case-control study using surveillance data and medical record reviews. Discontinuation due to thrombocytopenia, creatinine >2.0 mg/dl, bilirubin >2.0 mg/dl or severe reactions (generalized rash, persistent drug fever, or severe interference with methadone metabolism) were defined as appropriate for discontinuation of rifampin. All other reactions were classified as inappropriate.

RESULTS

Of 3,520 patients, rifampin was discontinued in 68 (1.9%); of these, 57% had rifampin discontinued unnecessarily. Treatment by an inexperienced provider (adjusted odds ratio [ORadj] 4.0; 95% confidence interval [CI] 1.9-8.5), race (ORadj 3.1; 95%CI 1.4-6.9), history of previous treatment (ORadj 4.8; 95%CI 1.9-12.5), and history of methadone drug treatment (ORadj 12.6; 95%CI 5.3-29.9) were all associated with inappropriate rifampin discontinuation.

CONCLUSION

True intolerance was rare, even among those patients infected with the human immunodeficiency virus. Most patients with minor reactions can successfully complete treatment with rifampin, particularly if managed by a physician experienced in the treatment of tuberculosis.

Directly observed treatment, short-course (DOTS): ensuring cure of tuberculosis

The WHO-recommended strategy for tuberculosis control is known as DOTS (Directly Observed Treatment, Short-course). Of importance here are description of WHO recommendations for tuberculosis control, of the scientific basis for these recommendations, and of outcomes in areas which have implemented these recommendations. Standardized definitions and reporting formats allow for systematic analysis of the quality of diagnosis and treatment, including international comparisons. As of 1999, more than 110 countries are implementing the DOTS strategy. Quality of both diagnosis and treatment are markedly better than in previous programmes. In DOTS areas, a majority of adult patients have smear-confirmed disease. Nearly 8 out of 10 patients treated in DOTS areas completed treatment and had negative smears at the end of treatment. However, less than one fourth of tuberculosis patients globally undergo treatment consistent with the principles of DOTS. The DOTS strategy for tuberculosis control allows for standardized, accurate diagnosis and effective treatment. By curing infectious patients and thereby stopping tuberculosis at the source, DOTS protects children and communities from spread of the disease. DOTS policies for diagnosis and treatment are easily adaptable to a pediatric population. India and other countries are in the process of rapid expansion of the DOTS strategy. Constructive cooperation from all sectors will be required for success of the programme.

Patient and health care system delays in the diagnosis and treatment of tuberculosis

SETTING

All culture-positive tuberculosis patients without previous treatment for tuberculosis (n = 184), New York City, April 1994.

OBJECTIVE

To examine factors associated with delays in presenting to a health care provider (patient delay) and in starting antituberculosis treatment (health care system delay).

DESIGN

Retrospective medical record review and patient interviews.

RESULTS

Median total delay was 57 days (range 4-764), 35 for acid-fast bacilli smear-positive patients and 79 for smear-negative patients (P < 0.001). Median patient delay was 25 (range 0-731). Median health care system delay was 15 days, 6 for smear-positive patients and 31 for smear-negative patients (P < 0.001). In logistic regression, age 55-64 years (adjusted odds ratio [OR(adj)] 10.6, 95% confidence interval [CI] 1.3-86.9), and primary language other than English (OR(adj) 2.5, 95%CI 1.0-5.8), were associated with longer patient delays. Homelessness (OR(adj) 7.1, 95%CI 1.05-33.5), not having a chest radiograph at the first medical visit (OR(adj) 2.4, 95%CI 1.0-5.4), negative smear (OR(adj) 10.2, 95%CI 4.4-23.3) and absence of cough (OR(adj) 2.9, 95%CI 1.2-6.8) were associated with longer health care system delays.

CONCLUSION

To reduce delays, patients should be educated to seek care more quickly, and should be provided with culturally appropriate health care and language services. Physicians should maintain a high index of suspicion for tuberculosis and perform appropriate diagnostic tests.

Chronic liver disease in central Harlem: the role of alcohol and viral hepatitis

For reasons not yet determined, chronic liver disease (CLD) has been a leading cause of excess morbidity and mortality in central Harlem. We conducted a case series and case-control analysis of demographic, clinical, epidemiological, and alcohol-intake-related information from patients with CLD and age- and sex-matched hospitalized control patients. Patients' sera were tested for markers of viral hepatitis. The presumed etiology of CLD among case-patients was as follows: both alcohol abuse and hepatitis C virus (HCV) infection, 24 persons (46% of case-patients); alcohol abuse alone, 15 (29%); HCV infection alone, 6 (12%); both alcohol abuse and chronic hepatitis B virus (HBV) infection, 3 (6%); and 1 each (2%) from: 1) schistosomiasis, 2) sarcoidosis, 3) unknown causes, and 4) alcohol abuse, chronic HBV, and HCV combined. In the case-control analysis, patients who had both alcoholism and either HBV (odds ratio [OR]: 6.3; 95% CI: 0. 5-334) or HCV (OR: 2.9; 95% CI: 1.3-6.2) were at increased risk for CLD, whereas patients who had only one of these three factors were not at increased risk for CLD. Patients who tested positive for the hepatitis G virus (HGV) did not have a significantly increased risk of CLD, and neither severity of CLD nor mortality was greater among these patients. Most patients in central Harlem who had CLD had liver damage from a combination of alcohol abuse and chronic viral hepatitis. Alcohol and hepatitis viruses appear to be synergistically hepatotoxic; this synergy appears to explain both the high rate of CLD in central Harlem and the recent reductions in this rate. Persons at risk for chronic HBV and HCV infection should be counseled about their increased risk of CLD if they consume excessive alcohol. Morbidity and mortality from liver disease could be decreased further by a reduction in alcohol consumption among persons who have chronic HBV and HCV infection, avoidance of needle sharing, and hepatitis B vaccination.

The use of legal action in New York City to ensure treatment of tuberculosis

BACKGROUND AND METHODS

After an increase in the number of cases of tuberculosis, New York City passed regulations to address the problem of nonadherence to treatment regimens. The commissioner of health can issue orders compelling a person to be examined for tuberculosis, to complete treatment, to receive treatment under direct observation, or to be detained for treatment. On the basis of a review of patients' records, we evaluated the use of these legal actions between April 1993 and April 1995.

RESULTS

Among more than 8000 patients with tuberculosis, regulatory orders were issued for less than 4 percent. Among patients with a variety of social problems, only a minority required regulatory intervention: 10 percent of those with injection-drug use, 16 percent of those with alcohol abuse, 17 percent of those who were homeless, 29 percent of those who used "crack" cocaine, and 38 percent of those with a history of incarceration. A total of 150 patients were ordered to undergo directly observed therapy, 139 patients to be detained during therapy, 12 patients to be examined for tuberculosis, and 3 patients to complete treatment. These 304 patients had a median of three prior hospitalizations related to tuberculosis and one episode of leaving the hospital against medical advice. Repeatedly noncompliant patients and those who left the hospital against medical advice were more likely than others to be detained. The median length of detention was 3 weeks for infectious patients and 28 weeks for noninfectious patients. As compared with patients ordered to receive directly observed therapy, the patients who were detained remained infectious longer, had left hospitals against medical advice more often, and were less likely to accept directly observed therapy voluntarily. Altogether, excluding those who died or moved, 96 percent of the patients completed treatment, and 2 percent continued to receive treatment for multidrug-resistant tuberculosis.

CONCLUSIONS

For most patients with tuberculosis, even those with severe social problems, completion of treatment can usually be achieved without regulatory intervention. Patients were detained on the basis of their history of tuberculosis, rather than on the basis of their social characteristics, and the less restrictive measure of mandatory directly observed therapy was often effective.

Prevalence and factors associated with tuberculosis infection among new school entrants, New York City, 1991-1993

SETTING

New York City public (or state-run) and private schools-elementary and secondary.

OBJECTIVE

To describe the prevalence and determine factors associated with positive tuberculin skin tests (TSTs) in school children.

DESIGN

Mandatory TST surveys among cohorts of new school entrants for the 1991, 1992 and 1993 school years, of whom birthplace was known for 81%. A positive tuberculin skin test defined as > or =10 mm induration.

RESULTS

Of the 298506 new school entrants, 2.1% (6326) were tuberculin test positive. The proportion that was tuberculin test positive was 0.5% (931/199 728) among US-born and 9.2% (3794/41 346) among foreign-born students. Foreign-born (FB) students with a history of BCG vaccination were much more likely to have a positive tuberculin test than US-born students (13.6% vs. 0.5%, odds ratio [OR] = 33.6, 95% confidence interval [CI] 31.7, 35.6), and were more likely to have a positive tuberculin test than FB students with no history of BCG (13.6% vs. 4.4%, OR = 3.4, 95% CI 2.5, 4.6). Older age was independently associated with tuberculin test positivity, except among foreign-born BCG-vaccinated children, in whom the youngest were more likely to have a positive tuberculin test.

CONCLUSIONS

Even in the midst of a tuberculosis resurgence such as that experienced by New York City, where tuberculosis cases nearly tripled from 1978 to 1992, the risk of tuberculosis infection among school children remained quite low. Given the reduced predictive value of the tuberculin test among low risk children and the effects of BCG vaccination, many children (especially younger children) with positive tuberculin test results are probably not infected with Mycobacterium tuberculosis. To reduce unnecessary evaluation and treatment, routine tuberculin tests should be administered only to high risk groups such as older children from countries with high rates of tuberculosis.

Purified protein derivative testing and tuberculosis preventive therapy for HIV-infected patients in New York City

OBJECTIVE

To determine whether Centers for Disease Control and Prevention recommendations for purified protein derivative (PPD) testing and tuberculosis (TB) preventive therapy for PPD-positive patients are implemented in HIV clinics.

DESIGN

Retrospective medical chart review.

SETTING

Ten hospital-based HIV clinics in New York City.

PARTICIPANTS

A total of 2397 patients with a first clinic visit in 1995.

OUTCOME MEASURES

PPD testing of eligible patients, and recommendation of preventive therapy and completion of regimen in PPD-positive patients.

METHOD

Outpatient medical records were abstracted for TB history, PPD testing, TB preventive therapy, and patient demographic, social and clinical characteristics. Multivariate analyses were performed using logistic regression.

RESULTS

Of 1342 patients with an indication for a PPD test, 865 (64%) were PPD tested in the clinic and 757 (88%) returned to have it read. Factors strongly associated with PPD testing in the clinic were number of visits, same sex behavior with men, and CD4+ lymphocyte count above 200 x 10(6)/l. Preventive therapy was recommended for 80% of newly identified PPD-positive patients and 22% of previously identified PPD-positive patients. Of 119 patients on preventive therapy in the clinic, 49 (41%) completed the regimen, 50 (42%) were lost to follow-up, and 20 (17%) discontinued therapy or their status could not be determined.

CONCLUSION

A significant number of missed opportunities to implement TB prevention practices were identified in HIV clinics. Focused attention in HIV clinics, and increased collaboration between HIV clinics and TB control programs may be needed to increase adherence to prevention guidelines.

Mycobacterium tuberculosis infection in a green-winged macaw (Ara chloroptera): report with public health implications

Mycobacterium tuberculosis was isolated from the eyelid, skin, tongue, and lungs of a green-winged macaw (Ara chloroptera). Two persons living in the same household were culture positive for pulmonary tuberculosis 3 to 4 years before tuberculosis was diagnosed in the bird. Although humans have not been shown to acquire tuberculosis from birds, an infected bird may be a sentinel for human infection.

A continuing outbreak of multidrug-resistant tuberculosis, with transmission in a hospital nursery

We investigated an increase in cases of multidrug-resistant tuberculosis (MDRTB) at a large urban facility where a prior nosocomial outbreak of MDRTB had occurred. Nosocomial transmission appeared to account for this outbreak as well, including a cluster of cases in a newborn nursery. Seven of 24 patients (29%) described in this investigation may have been exposed in the hospital nursery during an approximately 2-week period. We believe this to be the first documented outbreak of MDRTB in a hospital nursery. The transmission in the nursery demonstrates that the possibility of exposure to unrecognized active tuberculosis in nursery and hospital personnel is always present. Infection and active disease in the infants developed after a relatively short period of exposure. These findings underscore the need for adherence to published infection control guidelines in health care settings.

Isoniazid poisonings in New York City

We identified 41 New York City residents who had been hospitalized at least overnight between January 1992 and September 1993 because of a toxic isoniazid (INH) exposure. Review of the available medical charts of 33 patients revealed that median age was 19 years, 27 (82%) were females, and 24 (83%) were taking INH chemoprophylaxis for tuberculosis infection. Twenty-two patients had seizures. Twenty-seven (82%) patients had attempted suicide using INH, and another three patients had intentionally misused INH by making up missed doses at one time. All patients survived. Physicians should be aware of the potential for INH toxicity and should assess their patients' current mental and psychosocial status when prescribing it. INH toxicity should be considered when young patients, particularly females, present with unexplained intractable seizures, and treatment with pyridoxine should be given.

Rifampin-monoresistant tuberculosis in New York City, 1993-1994

All New York City patients whose cultures yielded Mycobacterium tuberculosis with isolated resistance to rifampin in 1993 and 1994 were included in this study. Of the 96 patients, 48 (50%) had primary resistance, 32 (33%) had acquired resistance, and 16 (17%) had unclassified resistance; 66% had histories of illicit drug use, and 79% were infected with human immunodeficiency virus (HIV). The median time to emergence of resistance was 40 weeks among the 32 patients with acquired resistance. Each of the HIV-infected patients with acquired resistance (cases, n = 29) was matched to two HIV-infected patients who had disease due to fully susceptible M. tuberculosis (controls, n = 58). In multivariate analysis, factors associated with the emergence of rifampin resistance were as follows: a sputum smear positive for acid-fast bacilli, advanced immunosuppression, and nonadherence to therapy.

Universal radiographic screening for tuberculosis among inmates upon admission to jail

OBJECTIVES

This study evaluated the efficacy of radiographic screening for tuberculosis in correctional facilities.

METHODS

Inmates at an admission facility in New York, NY, were screened for tuberculosis by registry cross-match, symptom interviews, tuberculin testing, and chest radiography.

RESULTS

Thirty-two cases of tuberculosis were detected among 4172 inmate admissions (767 cases per 100,000). Twenty-five inmates (78%) were previously diagnosed but incompletely treated; all were identified by registry cross-match. Seven inmates (22%) were newly diagnosed, of whom four (57%) were asymptomatic, had negative skin tests, and were detected only by their abnormal radiographs.

CONCLUSIONS

Screening strategies that limit radiographic testing to inmates with either positive skin tests or symptoms may result in missed opportunities for diagnosing active tuberculosis.

A continuing survey of drug-resistant tuberculosis, New York City, April 1994

BACKGROUND

A 1991 survey showed high levels of drug resistance among tuberculosis patients in New York, NY. As a result, the tuberculosis control program was strengthened, including expanded use of directly observed therapy and improved infection control.

METHODS

We collected isolates from every patient in New York City with a positive culture for Mycobacterium tuberculosis during April 1994; results were compared with those in the April 1991 survey.

RESULTS

From 1991 to 1994, the number of patients decreased from 466 to 332 patients. The percentage with isolates resistant to 1 or more antituberculosis drugs decreased from 33% to 24% (P < .01); with isolates resistant to at least isoniazid decreased from 26% to 18% (P < .05); and with isolates resistant to both isoniazid and rifampin decreased from 19% to 13% (P < .05). The number of patients with isolates resistant to both isoniazid and rifampin decreased by more than 50%. Among never previously treated patients, the percentage with resistance to 1 or more drugs decreased from 22% in 1991 to 13% in 1994 (P < .05). The number of patients with consistently positive culture results for more than 4 months decreased from 130 to 44. A history of antituberculosis treatment was the strongest predictor of drug resistance (odds ratio = 3.1; P < .001). Human immunodeficiency virus infection was associated with drug resistance among patients who never had been treated for tuberculosis.

CONCLUSIONS

Drug-resistant tuberculosis declined significantly in New York City from 1991 to 1994. Measures to control and prevent tuberculosis were associated with a 29% decrease in the proportion of drug resistance and a 52% decrease in the number of patients with multidrug-resistant tuberculosis.

Directly observed therapy in New York City. History, implementation, results, and challenges

The history of the New York City Department of Health Bureau of Tuberculosis Control Program, and the events leading to the adoption of wide-scale directly observed therapy (DOT) in 1992 are described. The organization and role of Department of Health and non-Department of Health directly observed programs are discussed. Details are provided regarding the Department of Health's program: the use of standard treatment and program protocols, the use of incentives and enablers, a profile of the successful DOT worker, the detention program, and other issues. Program data and outcomes from 1992 through 1995 are presented, along with some of the challenges and questions for the future.

Nonadherence in tuberculosis treatment: predictors and consequences in New York City

BACKGROUND

Poor adherence to antituberculosis treatment is the most important obstacle to tuberculosis control.

PURPOSE

To identify and analyze predictors and consequences of nonadherence to antituberculosis treatment.

PATIENTS AND METHODS

Retrospective study of a citywide cohort of 184 patients with tuberculosis in New York City, newly diagnosed by culture in April 1991-before the strengthening of its control program-and followed up through 1994. Follow-up information was collected through the New York City tuberculosis registry. Nonadherence was defined as treatment default for at least 2 months.

RESULTS

Eighty-eight of the 184 (48%) patients were nonadherent. Greater nonadherence was noted among blacks (unadjusted relative risk [RR] 3.0, 95% confidence interval [CI] 1.1 to 8.6, compared with whites), injection drug users (RR 1.5, 95% CI 1.1 to 2.0), homeless (RR 1.4, 95% CI 1.0 to 1.8), alcoholics (RR 1.4, 95% CI 1.0 to 1.9), and HIV-infected patients (RR 1.4, 95% CI 1.1 to 1.9); also, census-derived estimates of household income were lower among nonadherent patients (P = 0.018). In multivariate analysis, only injection drug use and homelessness predicted nonadherence, yet 46 (39%) of 117 patients who were neither homeless nor drug users were nonadherent. Nonadherent patients took longer to convert to negative culture (254 versus 64 days, P < 0.001), were more likely to acquire drug resistance (RR 5.6, 95% CI 0.7 to 44.2), required longer treatment regimens (560 versus 324 days, P < 0.0001), and were less likely to complete treatment (RR 0.5, 95% CI 0.4 to 0.7). There was no association between treatment adherence and all-cause mortality.

CONCLUSIONS

In the absence of public health intervention, half the patients defaulted treatment for 2 months or longer. Although common among the homeless and injection drug users, the problem occurred frequently and unpredictably in other patients. Nonadherence may contribute to the spread of tuberculosis and the emergence of drug resistance, and may increase the cost of treatment. These data lend support to directly observed therapy in tuberculosis.

The relationship between delayed or incomplete treatment and all-cause mortality in patients with tuberculosis

OBJECTIVE

To analyze the factors associated with survival in patients with pulmonary and extrapulmonary tuberculosis in New York City.

DESIGN

Observational study of a citywide cohort of tuberculosis cases.

SETTING

New York City, April 1991, before the strengthening of its control program.

PATIENTS

All 229 newly diagnosed cases of tuberculosis documented by culture in April 1991. Most patients (74%) were male, and the median age was 37 years (range, 1-89 years). In all, 89% belonged to minority groups. Human immunodeficiency virus (HIV) infection was present in 50% and multidrug resistance in 7% of the cases. Twenty-one patients (9%) were not treated.

MAIN OUTCOME MEASURES

Follow-up information was collected through the New York City tuberculosis registry; death from any cause was verified through the National Death Index.

RESULTS

Cumulative all-cause mortality by October 1994 was 44%; the median survival for those who died was 6.3 months (range, 0 days to 3 years). The most important baseline predictors of mortality, adjusted for baseline clinical and demographic factors, were acquired immunodeficiency syndrome (AIDS) (91% vs 11% in HIV-seronegative patients; Cox relative risk [RR], 7.8; 95% confidence interval [CI], 2.1-29.1), multidrug resistance (87% vs 39% in pansensitive cases; adjusted RR, 5.8; 95% CI, 2.3-14.5), and lack of treatment (81% vs 40%; adjusted RR, 3.1; 95% CI, 1.0-9.7). Also, 11 of 13 HIV-infected patients who started treatment after a 1-month delay died. Among 173 patients surviving the recommended treatment period, those who completed therapy (66%) had a lower subsequent mortality (20% vs 37%; RR, 0.5; 95% CI, 0.3-0.9).

CONCLUSIONS

Mortality from tuberculosis was high, even among patients without multidrug resistance who were not known to be infected with HIV. Most HIV-seropositive patients with delayed therapy died. Multidrug resistance predicted higher mortality, and treatment completion was associated with improved subsequent patient survival.

A multi-institutional outbreak of highly drug-resistant tuberculosis: epidemiology and clinical outcomes

OBJECTIVE

To investigate a multi-institutional outbreak of highly resistant tuberculosis and evaluate patient outcome.

DESIGN

Epidemiologic investigation of every tuberculosis case reported in New York City.

SETTING

Patients cared for at all public and nonpublic institutions from January 1, 1990, to August 1, 1993 (43 months).

PATIENTS

We reviewed medical and public health records and conducted clinical, epidemiologic, drug susceptibility, and restriction fragment length polymorphism (RFLP) analyses. A case was defined as tuberculosis in a patient with an isolate resistant to isoniazid, rifampin, ethambutol hydrochloride, and streptomycin (and rifabutin, if sensitivity testing included it), and, if RFLP testing was done, a pattern identical to or closely related to strain W.

MAIN OUTCOME MEASURES

Patient survival and the conversion of sputum cultures from positive to negative.

RESULTS

Of the 357 patients who met the case definition, 267 had identical or nearly identical RFLP patterns; isolates from the other 90 patients were not available for RFLP testing. Among these 267 patients, 86% were human immunodeficiency virus (HIV)-infected, 7% were HIV-negative, and 7% had unknown HIV status. All-cause mortality was 83%. Epidemiologic linkages were identified for 70% of patients, of whom 96% likely had nosocomially acquired disease at 11 hospitals. Survival was prolonged among patients who received medications to which their isolate was susceptible, especially capreomycin sulfate, and among patients with a CD4+ T-lymphocyte count greater than 0.200 x 10(9)/L (200/microL). Treatment with isoniazid and a fluoroquinolone antibiotic was also independently associated with longer survival.

CONCLUSIONS

This outbreak accounted for nearly one fourth of the cases of multidrug-resistant tuberculosis in the United States during a 43-month period. Most patients had nosocomially acquired disease, were infected with HIV, and unless promptly and appropriately treated, died rapidly. With appropriate directly observed treatment, especially combinations including an injectable medication, even severely immunocompromised patients had culture conversion and prolonged, tuberculosis-free survival.

The molecular epidemiology of tuberculosis in New York City: the importance of nosocomial transmission and laboratory error

SETTING

During the 1980s, New York City experienced a rapid increase of tuberculosis cases, more than 40% of which were human immunodeficiency virus (HIV)-associated.

OBJECTIVE

To better define the molecular epidemiology of tuberculosis in New York City.

DESIGN

We collected an isolate from every patient in New York City with a positive culture for Mycobacterium tuberculosis, including both incident and prevalent cases, in April 1991. Restriction fragment length polymorphism (RFLP) analysis using IS6110 was performed and the clinical, demographic, epidemiologic, and drug susceptibility patterns of patients were correlated with RFLP results.

RESULTS

Of 441 patients, 12 (3%) had laboratory, clinical, and RFLP evidence of falsely positive cultures. The remaining 429 patients had 252 distinct RFLP patterns. Patients with clustered 1-3 band isolates did not share demographic or drug susceptibility patterns. Eliminating these patients from the analysis, 344 patients remained, of whom 126 (37%) belonged to one of 31 clusters ranging in size from 2-17 patients (median cluster size = 3). Clustering was more common among patients with multidrug-resistant isolates (53%), African Americans (44%), and the homeless (49%), but was not associated with HIV infection or acquired immune deficiency syndrome (AIDS), Multidrug-resistance, being African American, and homelessness remained independently associated with clustering in multivariate analysis. Of 79 patients in clusters of > or = 4 patients, 25 (32%) had identifiable epidemiologic linkages; 17 (74%) of these patients, and 6% of all cases, were documented to have been nosocomially associated.

CONCLUSION

A small but non-negligible proportion (3%) of New York City patients had falsely positive cultures for M. tuberculosis as a result of laboratory error. More than one third of all patients and most patients with multidrug-resistance in April 1991 had clustered RFLP patterns, suggesting recent transmission of M. tuberculosis. Homelessness, multidrug-resistance, and being African American independently increased the risk of clustering. Most of the identified epidemiologic linkages and 6% of all cases resulted from transmission in hospitals.

Tuberculosis, AIDS, and death among substance abusers on welfare in New York City

BACKGROUND

In New York City, the incidence of tuberculosis has more than doubled during the past decade. We examined the incidence of tuberculosis and the acquired immunodeficiency syndrome (AIDS) and the rate of death from all causes in a very-high-risk group--indigent subjects who abuse drugs, alcohol, or both.

METHODS

In 1984 we began to study prospectively a cohort of welfare applicants and recipients 18 to 64 years of age who abused drugs or alcohol. The incidence rates of tuberculosis, AIDS, and death for this group were ascertained through vital records and New York City's tuberculosis and AIDS registries.

RESULTS

The cohort was followed for eight years. Of the 858 subjects, tuberculosis developed in 47 (5.5 percent), 84 (9.8 percent) were given a diagnosis of AIDS, and 183 (21.3 percent) died. The rates of incidence per 100,000 person-years were 744 for tuberculosis, 1323 for AIDS, and 2842 for death. In this group of welfare clients, the rate of newly diagnosed tuberculosis was 14.8 times that of the age-matched general population of New York City; the rate of AIDS was 10.0 times as high; and the death rate was 5.2 times as high. There was no significant difference in the rate of new cases of tuberculosis between subjects with positive skin tests and those with negative skin tests at examination in 1984.

CONCLUSIONS

Among indigent alcohol and drug abusers in New York City, the rates of tuberculosis, AIDS, and death are extremely high. In this population, a single positive or negative skin test does not predict the development of tuberculosis, probably because both anergy and new infections are common. If programs to control tuberculosis and AIDS are to be effective in groups of indigent substance abusers, health services must be integrated into the welfare delivery system.

Tuberculosis surveillance using death certificate data, New York City, 1992

OBJECTIVE

To determine the accuracy and frequency of reporting tuberculosis as either the contributing or underlying cause of death on death certificates in New York City during 1992.

METHODS

Death certificates from 1992 that listed tuberculosis were matched with the New York City tuberculosis registry. For those persons who had tuberculosis listed as a cause of death, but who were not listed in the registry, medical records were reviewed. The frequency of reporting tuberculosis on death certificates in patients who died with active tuberculosis was evaluated in the second part of this study. Death certificates of patients with active tuberculosis (persons who died within six months of starting anti-tuberculosis medications) in 1992 were reviewed.

RESULTS

Tuberculosis was listed on 635 death certificates; 377 (59%) were confirmed cases based on registry data. Reviews of medical records were possible for 230 (89%) of the remaining 258 patients and confirmed only two additional tuberculosis cases. Of 310 persons who died with active tuberculosis in 1992 (second part of the study), only 104 (34%) had tuberculosis listed on their death certificates.

CONCLUSIONS

In New York City, a diagnosis of tuberculosis on death certificates is an inaccurate measure of tuberculosis burden.

Tuberculosis screening among homeless persons with AIDS living in single-room-occupancy hotels

Congregate facilities for homeless persons with the acquired immunodeficiency syndrome (AIDS) are often endemic for tuberculosis. We evaluated tuberculosis screening methods at single-room-occupancy hotels housing persons with AIDS. Residents were screened by cross matching the New York City Tuberculosis Registry, interviewing for tuberculosis history, skin testing, and chest radiography. Cases were classified as either previously or newly diagnosed. Among the 106 participants, 16 (15%) previously diagnosed tuberculosis cases were identified. Participants' tuberculosis histories were identified by the questionnaire (100%) or by registry match (69%). Eight participants (50%) were noncompliant with therapy. These findings prompted the establishment of a directly observed therapy program on site.