How to ensure the continued resurgence of tuberculosis

SOCIAL, HISTORICAL AND CULTURAL DIMENSIONS OF TUBERCULOSIS

Tuberculosis (TB) researchers and clinicians, by virtue of the social disease they study, are drawn into an engagement with ways of understanding illness that extend beyond the strictly biomedical model. Primers on social science concepts directly relevant to TB, however, are lacking. The particularities of TB disease mean that certain social science concepts are more relevant than others. Concepts such as structural violence can seem complicated and off-putting. Other concepts, such as gender, can seem so familiar that they are left relatively unexplored. An intimate familiarity with the social dimensions of disease is valuable, particularly for infectious diseases, because the social model is an important complement to the biomedical model. This review article offers an important introduction to a selection of concepts directly relevant to TB from health sociology, medical anthropology and social cognitive theory. The article has pedagogical utility and also serves as a useful refresher for those researchers already engaged in this genre of work. The conceptual tools of health sociology, medical anthropology and social cognitive theory offer insightful ways to examine the social, historical and cultural dimensions of public health. By recognizing cultural experience as a central force shaping human interactions with the world, TB researchers and clinicians develop a more nuanced consideration of how health, illness and medical treatment are understood, interpreted and confronted.

How federalism shapes public health financing, policy, and program options

In the United States, fiscal and functional federalism strongly shape public health policy and programs. Federalism has implications for public health practice: it molds financing and disbursement options, including funding formulas, which affect allocations and program goals, and shapes how funding decisions are operationalized in a political context. This article explores how American federalism, both fiscal and functional, structures public health funding, policy, and program options, investigating the effects of intergovernmental transfers on public health finance and programs.

Protecting health care workers from tuberculosis in China: a review of policy and practice in China and the United States

Tuberculosis causes >1.7 million deaths worldwide each year and is frequently transmitted in hospitals. Outbreaks of multidrug-resistant tuberculosis have led to illness and death among health care workers (HCWs) in many countries. Some countries, such as the United States, implemented occupational health policies that substantially reduced tuberculosis rates among HCWs. Inadequate tuberculosis infection control in China may contribute to its high burden of tuberculosis and multidrug-resistant tuberculosis, which are both the second highest worldwide. Occupational health policies in China for tuberculosis control can be strengthened. We reviewed the development and content of tuberculosis infection control policies in the United States and China. Sources included published academic literature, Chinese Ministry of Health policies, US government agency reports, legal databases, personal observations of hospitals, review of internet discussion sites, and discussions with HCWs and health care and law experts. In the United States, slow acceptance of the tuberculosis problem in HCWs resulted in decades of inaction. Tuberculosis infection control policies, based mostly on expert opinion, were implemented only after tuberculosis resurged in the 1980s. Effective evidence-based policies were developed only after multiple cycles of policy implementation, evaluation and revision. These policies have now substantially reduced occupational tuberculosis. In China, tuberculosis has not been formally recognized as an occupational disease, and data regarding the burden in HCWs are sparse. Vagueness of current labour laws and suboptimal alignment of infection control authority and expertise result in varied and sometimes absent protection of HCWs against tuberculosis. Formal evaluations of occupational tuberculosis policies have not been reported. By collecting data on its current HCW tuberculosis burden and infection control practices, refining policies, continually evaluating its policies based on accumulated evidence and rapidly identifying unsuspected tuberculosis cases, China can develop a more comprehensive strategy to ensure the health of HCWs and reduce transmission of tuberculosis and multidrug-resistant tuberculosis.

American Thoracic Society/Centers for Disease Control and Prevention/Infectious Diseases Society of America: Controlling Tuberculosis in the United States

During 1993-2003, incidence of tuberculosis (TB) in the United States decreased 44% and is now occurring at a historic low level (14,874 cases in 2003). The Advisory Council for the Elimination of Tuberculosis has called for a renewed commitment to eliminating TB in the United States, and the Institute of Medicine has published a detailed plan for achieving that goal. In this statement, the American Thoracic Society (ATS), Centers for Disease Control and Prevention (CDC), and the Infectious Diseases Society of America (IDSA) propose recommendations to improve the control and prevention of TB in the United States and to progress toward its elimination. This statement is one in a series issued periodically by the sponsoring organizations to guide the diagnosis, treatment, control, and prevention of TB. This statement supersedes the previous statement by ATS and CDC, which was also supported by IDSA and the American Academy of Pediatrics (AAP). This statement was drafted, after an evidence-based review of the subject, by a panel of representatives of the three sponsoring organizations. AAP, the National Tuberculosis Controllers Association, and the Canadian Thoracic Society were also represented on the panel. This statement integrates recent scientific advances with current epidemiologic data, other recent guidelines from this series, and other sources into a coherent and practical approach to the control of TB in the United States. Although drafted to apply to TB-control activities in the United States, this statement might be of use in other countries in which persons with TB generally have access to medical and public health services and resources necessary to make a precise diagnosis of the disease; achieve curative medical treatment; and otherwise provide substantial science-based protection of the population against TB. This statement is aimed at all persons who advocate, plan, and work at controlling and preventing TB in the United States, including persons who formulate public health policy and make decisions about allocation of resources for disease control and health maintenance and directors and staff members of state, county, and local public health agencies throughout the United States charged with control of TB. The audience also includes the full range of medical practitioners, organizations, and institutions involved in the health care of persons in the United States who are at risk for TB.

Tuberculosis

Tuberculosis is an infectious disease caused by bacteria in the Mycobacterium tuberculosis complex. Of these, the most common species to infect humans is M. tuberculosis. The TB bacillus is an extremely successful human pathogen, infecting two billion persons worldwide; an estimated 2 to 3 million people die from tuberculosis each year. In the United States, TB rates decreased steadily at the rate of 5% per year from 1953 until 1985 when the trend reversed, with the number of TB cases peaking in 1992. Outbreaks of multidrug-resistant TB (MDR TB) were reported, and these cases were documented to be transmitted in nosocomial and congregate settings, including hospitals and prisons. AIDS patients infected with M. tb developed disease rapidly, and case-fatality rates of >80% were noted in those infected with multidrug-resistant M. tb. Intensive intervention, at enormous cost, caused the number of TB cases to decline. This article discusses factors that led to the increase in TB cases, their subsequent decline, and measures needed in the future if TB is to be eliminated in the United States.

Spatial patterns of tuberculosis incidence in Cologne (Germany)

In many European countries, the decline of tuberculosis notification rates levelled off in the mid 1980s. Germany has been facing only a very modest resurgence of tuberculosis (TB) in the early 1990s, but until now, the notification rate does not yet fulfil the WHO definition of a low incidence country. Mainly immigration from high incidence countries is held responsible for the delayed decline and temporary increase of TB. This paper seeks to investigate the inner-urban strength of association between tuberculosis and several potential risk factors in the city of Cologne using geographical and statistical methods within a small-area division based, GIS-supported ecological study, which never before has been conducted for a German city. Standardised annual TB incidence rates for 78 urban subdistricts between 1986 and 1997, disaggregated by age, have been analysed. Twelve independent variables representing contemporary ethnic and socioeconomic conditions are used to calculate Poisson regression models. For the entire population and for the <60 age group, a strong positive association was found between tuberculosis incidence and share of immigrants. Interestingly enough the share of German-origin immigrants from eastern Europe was seen not to be instrumental in increasing TB rates. Reflecting strong ecological correlations between variables depicting economic conditions and TB as well as immigration variables, the deprivation of certain ethnicities rather than high prevalence immigration background is inferred to be significant to TB level. As for the 60 + age group regression analysis fails to model the TB incidence patterns sufficiently it seems reasonable to assume an autonomous, spatially disaggregated TB epidemic of the elderly, echoing a severe post-war epidemic by reactivation, only marginally associated with contemporary living conditions, but contributing substantially to the current TB incidence level. This assumption is reinforced by further results of the statistical analysis (deviance of regression null models, testing for Normal distribution, time trends). It could be shown that in Cologne the HIV/AIDS epidemic is not significantly influencing the TB incidence rate of men aged 30-49 being the most AIDS-afflicted population subgroup.

Poor micronutrient status of active pulmonary tuberculosis patients in Indonesia

Malnutrition is observed frequently in patients with pulmonary tuberculosis (TB), but their nutritional status, especially of micronutrients, is still poorly documented. The objective of this study was to investigate the nutritional status of patients with active TB compared with that of healthy controls in Jakarta, Indonesia. In a case-control study, 41 out-patients aged 15-55 y with untreated active pulmonary TB were compared with 41 healthy controls selected from neighbors of the patients and matched for age and sex. Cases had clinical and radiographic abnormalities consistent with pulmonary TB and at least two sputum specimens showing acid-fast bacilli. Anthropometric and micronutrient status data were collected. Compared with the controls, TB patients had significantly lower body mass index, skinfold thicknesses (triceps, biceps, subscapular, suprailiac), mid-upper arm circumference, proportion of fat, and concentrations of serum albumin, blood hemoglobin, plasma retinol and plasma zinc, whereas plasma zinc protoporphyrin concentration, as a measure of free erythrocyte protoporphyrin concentration, was greater. When patients and controls were subdivided on the basis of nutritional status, concentrations of serum albumin, blood hemoglobin, and zinc and retinol in plasma were lower in malnourished TB patients than in well-nourished healthy controls, well-nourished TB patients and malnourished healthy controls. In conclusion, the nutritional status of patients with active pulmonary TB was poor compared with healthy subjects, i.e., significantly more patients were anemic and more had low plasma concentrations of retinol and zinc. Low concentrations of hemoglobin, and of retinol and zinc in plasma were more pronounced in malnourished TB patients.

Encompassing treatment with prevention: the path for a lasting control of tuberculosis

Tuberculosis is an important cause of death, mainly in the less developed countries. Thus far the strategy for its control had relied on the diagnosis of sick individuals and provision of chemotherapy. However, this strategy is problematic for several reasons: poor education about the disease and the low income of people with tuberculosis are important barriers for them to have access to early diagnosis and to keep adherence to treatment; provision of 'preventive therapy' to the enormous pool of people infected with tuberculosis is not feasible in less developed countries; and finally, long-term political commitment with the strategy is unlikely. Several facts indicate that tuberculosis patterns in different populations are shaped by biological, behavioral and socio-economic factors. This paper argues that a lasting control of tuberculosis requires a strategy based on a broader model of causality, which takes account of all these three causal factors.

Emerging infectious diseases: public health issues for the 21st century

Infectious diseases are the third leading cause of death in the United States and the leading cause worldwide. As the new millennium approaches, the public health community must replenish capacity depleted during years of inadequate funding while simultaneously incorporating new technologies and planning for the longer term. Among the challenges facing the public health community is the need for coordinated, global, multisectoral approaches to preventing and controlling complex infectious disease problems.

The fall after the rise: Tuberculosis in the United States, 1991 through 1994

OBJECTIVES

Factors associated with decreases in tuberculosis cases observed in the United States in 1993 and 1994 were analyzed.

METHODS

Changes in case counts reported to the national surveillance system were evaluated by dividing the number of incident cases of TB reported in 1993 and 1994 by the number of cases reported in 1991 and 1992 and stratifying these ratios by demographic factors, AIDS incidence, and changes in program performance.

RESULTS

Case counts decreased from 52,956 in 1991 and 1992 to 49,605 in 1993 and 1994 (case count ratio = 0.94, 95% confidence interval [CI] = 0.93, 0.95). The decrease, confined to US-born patients, was generally associated with AIDS incidence and improvements in completion of therapy, conversion of sputum, and increases in the number of contacts identified per case.

CONCLUSIONS

Recent TB epidemiology patterns suggest that improvements in treatment and control activities have contributed to the reversal in the resurgence of this disease in US-born persons. Continued success in preventing the occurrence of active TB will require sustained efforts to ensure appropriate treatment of cases.

Multi-drug resistant tuberculosis in Finland--a forecast

Since the collapse of the Soviet system, travel between the St Petersburg district and the Baltic states and Finland has increased substantially. Although it is difficult to obtain exact figures on the number of cases of tuberculosis (TB) and multi-drug resistant (MDR) TB in these countries, there is strong evidence of growing epidemics, bringing added epidemiological threat to Finland. The purpose of this study is to produce a short-term "worst case" forecast of the spatial development of a threatened MDR-TB epidemic in Finland. The method applied is a chorological multistep procedure using statistical and geographical methods and a simulation technique. Instead of focusing on populations of carriers and susceptibles, emphasis is placed on identifying the primary influences directing the epidemic as a spatial process. This was done by dividing Finland into small-area units and by assigning the risk of obtaining MDR-TB to each unit based on socioeconomic and structural characteristics of the population. The simulated 6 year cumulative distribution of new MDR-TB cases showed a marked concentration of cases in the capital region and in a cluster of municipalities along the west coast. Although socioeconomic factors are important in explaining the distribution of cases, frequent and widespread international contacts seemed to be equally important at the beginning of the epidemic.

Mycobacterium tuberculosis miniepidemic in a church gospel choir

BACKGROUND

Conventional contact investigation and molecular fingerprinting of Mycobacterium tuberculosis isolates in tuberculosis (TB) outbreaks have facilitated recognition as well as application of public health control activities. Singing in a choir as an activity that promotes TB transmission has been occasionally recognized. Such avocational transmission in a middle class community can occur with attendant difficulties encountered in contact investigation.

METHODS

Five cases of TB (one index case; three secondary cases; one unassociated case) were identified among members of a famous church gospel choir in Newark, NJ. DNA fingerprinting and susceptibility testing were done on all retrieved strains. Of 306 choir members who had tuberculin tests, 19% were reactors. The presumed outbreak site was investigated.

RESULTS

Four of the five patients were tenors, and one was an alto. Tenors were approximately twice as likely to be tuberculin reactors than subjects with other vocal ranges combined (relative risk, 2.04; 95% confidence interval, 1.17 to 3.56). An air ventilation outlet was directly in front of the tenor section. Some limited extra-church activity between choir members may have contributed to transmission.

CONCLUSION

Conventional contact investigation must be supplemented by newer techniques, such as DNA fingerprinting, in identifying possible outbreak transmission. Singing, location of a ventilation outlet, and exposure time may have contributed to TB transmission in this outbreak. Transmission need not only be in congregate settings among well-defined socioeconomic groups but may occur unexpectedly in middle class communities.

Geographic diversity in tuberculosis trends and directly observed therapy, New York City, 1991 to 1994

The New York City tuberculosis (TB) case rate declined from 1991 to 1994 following more than a decade of increases. The present study investigated TB trends in New York City neighborhoods and their association with neighborhood-specific rates of application of directly observed therapy (DOT). Using Poisson regression models, TB trends in each of New York City's 30 health districts were classified as increasing, decreasing, or stable, as indicated respectively by significant positive, negative, or nonsignificant regression coefficient. Case counts increased in four health districts, decreased in 10, and were stable in 16. Decreasing TB was associated with a higher rate of application of DOT. TB cases among foreign-born persons increased in 12 health districts and were stable in 18, whereas cases among persons born in the United States decreased in 19 and were stable in 11 districts. Among the foreign-born, increasing TB was not associated with a lesser rate of application of DOT. These data provide some support for the role of DOT in containing TB, but also suggest that the application of DOT among foreign-born residents is less effective than among United States-born residents. This may be due to a greater proportion of TB cases among the foreign-born being due to reactivation of TB rather than new infection.

MULTIDRUG RESISTANT TUBERCULOSIS - BIOMECHANISM, EPIDEMIOLOGY AND MANAGEMENT STRATEGIES

Muitidrug resistant tuberculosis has shown an alarming increase and this assumes added importance in view of the increasing number of HIV infected patients. This article reviews the biomechanism of resistance and discusses the present stategies that are available and recommended to tackle the rising incidence of tuberculosis due to resistant mycobacteria.