The U-shaped curve of concern

Impact of the COVID-19 pandemic on contact tracing of patients with pulmonary tuberculosis

Background

The COVID-19 pandemic could have negative effects on tuberculosis (TB) control. The objective was to assess the impact of the pandemic in contact tracing, TB and latent tuberculosis infection (LTBI) in contacts of patients with pulmonary TB in Catalonia (Spain).

Methods

Contact tracing was carried out in cases of pulmonary TB detected during 14 months in the pre-pandemic period (1 January 2019 to 28 February 2020) and 14 months in the pandemic period (1 March 2020 to 30 April 2021). Contacts received the tuberculin skin test and/or interferon gamma release assay and it was determined whether they had TB or LTBI. Variables associated with TB or LTBI in contacts (study period and sociodemographic variables) were analyzed using adjusted odds ratio (aOR) and the 95% confidence intervals (95% CI).

Results

The pre-pandemic and pandemic periods showed, respectively: 503 and 255 pulmonary TB reported cases (reduction of 50.7%); and 4676 and 1687 contacts studied (reduction of 36.1%). In these periods, the proportion of TB cases among the contacts was 1.9% (84/4307) and 2.2% (30/1381) (P = 0.608); and the proportion of LTBI was 25.3% (1090/4307) and 29.2% (403/1381) (P < 0.001). The pandemic period was associated to higher LTBI proportion (aOR = 1.3; 95% CI 1.1–1.5), taking into account the effect on LTBI of the other variables studied as sex, age, household contact and migrant status.

Conclusions

COVID-19 is affecting TB control due to less exhaustive TB and LTBI case detection. An increase in LTBI was observed during the pandemic period. Efforts should be made to improve detection of TB and LTBI among contacts of TB cases.

Parallels and Mutual Lessons in Tuberculosis and COVID-19 Transmission, Prevention, and Control

The coronavirus disease (COVID-19) pandemic has had unprecedented negative effects on global health and economies, drawing attention and resources from many other public health services. To minimize negative effects, the parallels, lessons, and resources from existing public health programs need to be identified and used. Often underappreciated synergies relating to COVID-19 are with tuberculosis (TB). COVID-19 and TB share commonalities in transmission and public health response: case finding, contact identification, and evaluation. Data supporting interventions for either disease are, understandably, vastly different, given the diseases' different histories. However, many of the evolving issues affecting these diseases are increasingly similar. As previously done for TB, all aspects of congregate investigations and preventive and therapeutic measures for COVID-19 must be prospectively studied for optimal evidence-based interventions. New attention garnered by the pandemic can ensure that knowledge and investment can benefit both COVID-19 response and traditional public health programs such as TB programs.

Epidemiology of Tuberculosis in the United States

Although considerable progress has been made in reducing US tuberculosis incidence, the goal of eliminating the disease from the United States remains elusive. A continued focus on preventing new tuberculosis infections while also identifying and treating persons with existing tuberculosis infection is needed. Continued vigilance to ensure ongoing control of tuberculosis transmission remains key.

Tuberculosis in Canada and the United States: a review of trends from 1953 to 2015

OBJECTIVES

To explore tuberculosis (TB) incidence in Canada and the United States from 1953 to 2015. In the most recent decade, the US incidence was lower than that of Canada. Since both countries are high income and have low TB incidence with similar TB surveillance programs, we hypothesized that rates should be similar.

METHODS

TB incidence data from 1953 to 2015 were retrieved for both countries. Joinpoint regression was performed to identify change points in the trend, and direct standardization of US rates using Canadian ethnic population distribution was calculated. Adjusted rate and average annual percent change (AAPC) were estimated.

RESULTS

Canada rates/100,000 were higher from 1953 to 1974 and similar from 1975 to 1985. This coincided with a change in US case definition in 1975. US rates were higher from 1986 to 1996. HIV/TB coinfection in the USA was 10.2% compared to that of Canada, 1.6%. Rates were similar from 1997 to 2004. Canada rates were again higher from 2005 to 2015. The Canada average AAPC rate in 1975-2015 was lower, - 2.9%, compared to that of the USA, - 4.1%. Foreign-born and Indigenous population proportions were 20.2% and 4.2% for Canada and 12.9% and 1.7% for the USA. The US rate adjusted to the Canada ethnic composition was 4.8 compared to the Canadian rate of 4.7.

CONCLUSION

Case definition change and HIV coinfection contributed to the 1980 US rate increase. TB rates decreased in both countries from 1997, but more rapidly in the USA. The Canada proportion of foreign-born and Indigenous populations was higher. When US rates were standardized by Canada ethnic distribution, the national rates were similar. Further exploration of factors contributing to differences between these countries is needed.

Does the economic recession influence the incidence of pertussis in a cosmopolitan European city?

Background

In the last few years, pertussis has re-emerged worldwide. The aim of this article is to study how the incidence of the disease has evolved in Barcelona city over a 16-year period, and determine which factors are associated with the evolution of the disease. We discuss the causes of the observed changes considering different possibilities such as vaccination coverage, vaccine effectiveness, increased surveillance or the effect of the current economic recession.

Methods

We performed a cross-sectional, observational, population-based descriptive study using data for the 2000–2015 period from the notifiable diseases register maintained by Barcelona Public Health Agency. We used Poisson regression to compute adjusted odds ratios (aOR) and their corresponding 95% confidence intervals (CI).

Results

A total of 1791 cases were registered. The incidence of the disease increased throughout the city from 2011 onwards. While children under 1 year of age had the highest-incidence and were the most at risk (aOR = 27.18, CI:23.51–31.44), we found that the age of affected children was higher in the last years. Incidence proportion (PRR) was lower among foreign-born children than native children (PRR = 0.43 CI:0.32–0.58). In the whole-cell vaccine period (2000–2004), the percentage of cases under 1 year of age who received the vaccine was lower than in 2005–2015 when the acellular vaccine was used (p = 0.01), suggesting a lower efficacy of the acellular vaccine. However, vaccination coverage in children under 6 years remained high (~ 90%), and there were no significant year-to-year variations (p = 0.757). Moreover, there did not appear to be any significant restrictions in medical care. According to the index of disposable household income (DHI), pertussis incidence increased from 2011 onwards in all neighbourhoods and remained higher in those with lower DHI.

Conclusions

The noteworthy increase in pertussis incidence does not seem to be due to the economic recession, but to other factors here described.

Outbreak of Drug-Resistant Mycobacterium tuberculosis Among Homeless People in Atlanta, Georgia, 2008-2015

OBJECTIVES

Our objective was to describe and determine the factors contributing to a recent drug-resistant tuberculosis (TB) outbreak in Georgia.

METHODS

We defined an outbreak case as TB diagnosed from March 2008 through December 2015 in a person residing in Georgia at the time of diagnosis and for whom (1) the genotype of the Mycobacterium tuberculosis isolate was consistent with the outbreak strain or (2) TB was diagnosed clinically without a genotyped isolate available and connections were established to another outbreak-associated patient. To determine factors contributing to transmission, we interviewed patients and reviewed health records, homeless facility overnight rosters, and local jail booking records. We also assessed infection control measures in the 6 homeless facilities involved in the outbreak.

RESULTS

Of 110 outbreak cases in Georgia, 86 (78%) were culture confirmed and isoniazid resistant, 41 (37%) occurred in people with human immunodeficiency virus coinfection (8 of whom were receiving antiretroviral treatment at the time of TB diagnosis), and 10 (9%) resulted in TB-related deaths. All but 8 outbreak-associated patients had stayed overnight or volunteered extensively in a homeless facility; all these facilities lacked infection control measures. At least 9 and up to 36 TB cases outside Georgia could be linked to this outbreak.

CONCLUSIONS

This article highlights the ongoing potential for long-lasting and far-reaching TB outbreaks, particularly among populations with untreated human immunodeficiency virus infection, mental illness, substance abuse, and homelessness. To prevent and control TB outbreaks, health departments should work with overnight homeless facilities to implement infection control measures and maintain searchable overnight rosters.

Tuberculosis Outbreaks in the United States, 2009-2015

OBJECTIVES

The Centers for Disease Control and Prevention provides on-site epidemiologic assistance for outbreak response when the health capacity of state, tribal, local, and territorial health departments has been exceeded. We examined recent outbreaks of tuberculosis (TB) for which health departments needed assistance.

METHODS

We defined a TB outbreak as detection of ≥3 TB cases related by transmission, as suggested by routine genotyping and epidemiologic linkages. We conducted retrospective reviews of documentation from all 21 TB outbreak investigations in the United States for which the Centers for Disease Control and Prevention provided on-site assistance during 2009-2015. We abstracted data on patients' demographic characteristics and TB risk factors, as well as factors contributing to the outbreak from trip reports written by on-site investigators, and we compared these with outbreaks investigated during 2002-2008.

RESULTS

The 21 TB outbreaks during 2009-2015 involved 457 outbreak patients (range, 3-99 patients per outbreak). Of the 21 outbreaks, 16 were first identified through genotype data. In sum, 118 (26%) patients were identified through contact investigations of other patients in the outbreak. Most outbreak patients (n = 363, 79%) were US born. Ninety-two (26%) patients had a mental illness, 204 (45%) had been homeless in the year before diagnosis, and 379 (83%) used alcohol excessively or used illicit substances. The proportion of patients experiencing homelessness doubled between 2002-2008 and 2009-2015; other characteristics were similar between the 2 periods. Delayed TB diagnosis contributed to unmitigated transmission in all but 1 outbreak.

CONCLUSIONS

TB outbreaks challenge frontline public health resources. Genotyping and contact investigations are important strategies for detecting and controlling TB outbreaks, particularly among people experiencing homelessness or those with mental illness.

Mind the gap: TB trends in the USA and the UK, 2000-2011

BACKGROUND

TB remains a major public health concern, even in low-incidence countries like the USA and the UK. Over the last two decades, cases of TB reported in the USA have declined, while they have increased substantially in the UK. We examined factors associated with this divergence in TB trends between the two countries.

METHODS

We analysed all cases of TB reported to the US and UK national TB surveillance systems from 1 January 2000 through 31 December 2011. Negative binominal regression was used to assess potential demographic, clinical and risk factor variables associated with differences in observed trends.

FINDINGS

A total of 259,609 cases were reported. From 2000 to 2011, annual TB incidence rates declined from 5.8 to 3.4 cases per 100,000 in the USA, whereas in the UK, TB incidence increased from 11.4 to 14.4 cases per 100,000. The majority of cases in both the USA (56%) and the UK (64%) were among foreign-born persons. The number of foreign-born cases reported in the USA declined by 15% (7731 in 2000 to 6564 in 2011) while native-born cases fell by 54% (8442 in 2000 to 3883 in 2011). In contrast, the number of foreign-born cases reported in the UK increased by 80% (3380 in 2000 to 6088 in 2011), while the number of native-born cases remained largely unchanged (2158 in 2000 to 2137 in 2011). In an adjusted negative binomial regression model, significant differences in trend were associated with sex, age, race/ethnicity, site of disease, HIV status and previous history of TB (p<0.01). Among the foreign-born, significant differences in trend were also associated with time since UK or US entry (p<0.01).

INTERPRETATION

To achieve TB elimination in the UK, a re-evaluation of current TB control policies and practices with a focus on foreign-born are needed. In the USA, maintaining and strengthening control practices are necessary to sustain the progress made over the last 20 years.

Coal mine dust lung disease. New lessons from old exposure

Coal mining remains a sizable industry, with millions of working and retired coal miners worldwide. This article provides an update on recent advances in the understanding of respiratory health issues in coal miners and focuses on the spectrum of disease caused by inhalation of coal mine dust, termed coal mine dust lung disease. In addition to the historical interstitial lung diseases (coal worker's pneumoconiosis, silicosis, and mixed dust pneumoconiosis), coal miners are at risk for dust-related diffuse fibrosis and chronic airway diseases, including emphysema and chronic bronchitis. Recent recognition of rapidly progressive pneumoconiosis in younger miners, mainly in the eastern United States, has increased the sense of urgency and the need for vigilance in medical research, clinical diagnosis, and exposure prevention. Given the risk for disease progression even after exposure removal, along with few medical treatment options, there is an important role for chest physicians in the recognition and management of lung disease associated with work in coal mining.

Factors that influence current tuberculosis epidemiology

According to WHO estimates, in 2010 there were 8.8 million new cases of tuberculosis (TB) and 1.5 million deaths. TB has been classically associated with poverty, overcrowding and malnutrition. Low income countries and deprived areas, within big cities in developed countries, present the highest TB incidences and TB mortality rates. These are the settings where immigration, important social inequalities, HIV infection and drug or alcohol abuse may coexist, all factors strongly associated with TB. In spite of the political, economical, research and community efforts, TB remains a major global health problem worldwide. Moreover, in this new century, new challenges such as multidrug-resistance extension, migration to big cities and the new treatments with anti-tumour necrosis alpha factor for inflammatory diseases have emerged and threaten the decreasing trend in the global number of TB cases in the last years. We must also be aware about the impact that smoking and diabetes pandemics may be having on the incidence of TB. The existence of a good TB Prevention and Control Program is essential to fight against TB. The coordination among clinicians, microbiologists, epidemiologists and others, and the link between surveillance, control and research should always be a priority for a TB Program. Each city and country should define their needs according to the epidemiological situation. Local TB control programs will have to adapt to any new challenge that arises in order to respond to the needs of their population.

The value of effective public tuberculosis treatment: an analysis of opportunity costs associated with multidrug resistant tuberculosis in Latvia

BACKGROUND

A challenge to effective protection against tuberculosis is to sustain expensive and complex treatment public programs. Potential consequences of program failure include acquired drug resistance, poor patient outcomes, and potentially much higher system costs, however. In contrast, effective efforts have value illustrated by impacts they prevent. We compared the healthcare costs and treatment outcomes among multidrug-resistant tuberculosis (MDR-TB) and non MDR-TB patients in Latvia to identify benefits or costs associated with both.

METHODS

We measured and compared costs, healthcare utilization, and outcomes for patients who began treatment through Latvia's TB control program in 2002 using multivariate regression analysis and negative binomial regression.

RESULTS

We analyzed data for 92 MDR-TB and 54 non MDR-TB patients. Most (67%) MDR-TB patients had history of prior tuberculosis treatment. MDR-TB was associated with lower cure rates (71% vs. 91%) and greater resource utilization. MDR-TB treatment cost almost $20,000 more than non MDR-TB.

CONCLUSION

Up to 2/3 of MDR-TB treated in our sample was preventable at a potential savings of over $1.3 million in healthcare resources as well as substantial individual health.

Trends in mortality of tuberculosis patients in the United States: the long-term perspective

PURPOSE

To describe long-term trends in tuberculosis (TB) mortality and to compare trends estimated from two different sources of public health surveillance data.

METHODS

Trends and changes in trend were estimated by joinpoint regression. Comparisons between data sets were made by fitting a Poisson regression model.

RESULTS

Since 1900, TB mortality rates estimated from death certificates have declined steeply, except for a period of no change in the 1980s. This decade had long-term consequences resulting in more TB deaths in later years than would have occurred had there been no flattening of the trend. Recent trends in TB mortality estimated from National Tuberculosis Surveillance System (NTSS) data, which record all-cause mortality, differed from trends based on death certificates. In particular, NTSS data showed TB mortality rates flattening since 2002.

CONCLUSIONS

Estimates of trends in TB mortality vary by data source, and therefore interpretation of the success of control efforts will depend on the surveillance data set used. The data sets may be subject to different biases that vary with time. One data set showed a sustained improvement in the control of TB since the early 1990s whereas the other indicated that the rate of TB mortality was no longer declining.

Is the eradication of tuberculosis 'yesterday's ambition' or 'tomorrow's triumph'?

Tuberculosis (TB) remains a serious infectious disease continuing to cause around 1.8 million deaths annually. The great paradox is that despite the availability of effective treatment for the past 60 years, it continues to spread relentlessly, particularly in sub-Saharan Africa due to the fuelling effect of the HIV/AIDS epidemic. It is no longer a medical epidemic, but an epidemic of injustice. Increased political and financial investment by the industrially developed nations, as well as sustained political will in the affected countries, is required to bring TB under control. It is imperative that the control should be linked to that of HIV which is also closely associated with poverty, poor housing and malnutrition. The historical, social, philosophical and political perspectives that may have influenced the failure of TB control are discussed. Once again, therefore, the question is raised--can TB be brought under control?

The societal cost of tuberculosis: Tarrant County, Texas, 2002

PURPOSE

Cost analyses of tuberculosis (TB) in the United States have not included elements that may be prevented if TB were prevented, such as losses associated with TB-related disability, personal and other costs to society. Unmeasured TB costs lead to underestimates of the benefit of prevention and create conditions that could result in a resurgence of TB. We gathered data from Tarrant County, Texas, for 2002, to estimate the societal cost due to TB.

METHODS

We estimated societal costs due to the presence or suspicion of TB using known variable and fixed costs incurred to all parties. These include costs for infrastructure; diagnostics and surveillance; inpatient and outpatient treatment of active, suspected, and latent TB infection (LTBI); epidemiologic activities; personal costs borne by patients and by others for lost time, disability, and death; and the cost of secondary transmission. A discount rate of 3% was used.

RESULTS

During 2002, 108 TB cases were confirmed in Tarrant County, costing an estimated $40,574,953. The average societal cost per TB illness was $ 376,255. Secondary transmission created 47% and pulmonary impairment after TB created 35.4% of the total societal cost per illness.

CONCLUSIONS

Prior estimates have concluded that treatment costs constitute most (86%) TB-related expenditures. From a societal perspective treatment and other direct costs account for little (3.3%) of the full burden. These data predict that preventing infection through earlier TB diagnosis and treatment of LTBI and expanding treatment of LTBI may be the most feasible strategies to reduce the cost of TB.

Primary tuberculous lymphadenitis: A case report

Tuberculosis (TB) is a prevalent systemic bacterial infectious disease usually caused by Mycobacterium tuberculosis. It is estimated that approximately 8 million people develop TB each year, and 3 million people die of complications associated with the disease. In this article we report a case of a 17-year-old female patient with a painful swelling in her right submandibular region. She was diagnosed with right submandibular tuberculous lymphadenitis. Tuberculous lymphadenitis, when occurring in the cervical region, continues to be a common cause of extrapulmonary TB. TB is a recognized occupational risk for dentists, as they work in close proximity to the nasal and oral cavities of patients, with the possible generation of potentially infectious sprays during routine operative procedures.

Human immunodeficiency virus testing among patients with tuberculosis at a university hospital in Taiwan, 2000 to 2006

BACKGROUND/PURPOSE

Human immunodeficiency virus (HIV)-infected patients are more susceptible to tuberculosis (TB), which might be the initial presentation of HIV infection. This study assessed the frequency and results of HIV testing among patients diagnosed with TB at a university hospital from 2000 to 2006.

METHODS

Surveillance data for all reported TB cases from 2000 to 2006 were reviewed to identify patients with unknown HIV serostatus who received HIV testing when TB was diagnosed. Trends in HIV testing among TB patients were examined, and factors associated with HIV infection were analyzed.

RESULTS

From 2000 to 2006, 3643 patients were diagnosed with TB, and 49 with HIV infection prior to TB diagnosis were excluded. Of the 3594 patients with unknown HIV status before TB diagnosis, 1035 (28.8%) were offered HIV testing. There was an increasing trend of providing HIV testing to TB patients that ranged from 16.1% to 43.7% (p < 0.001), and the overall prevalence of HIV infection among TB patients was 5.6% (95% CI, 4.3-7.1%) of those tested. Compared with TB patients without HIV infection, those with HIV infection were more likely to be aged < 50 years [adjusted odds ratio (aOR), 8.0; 95% CI, 4.4-14.6), male (aOR, 7.1; 95% CI, 3.0-16.9), and present with extrapulmonary TB (aOR, 2.8; 95% CI, 1.7-4.6).

CONCLUSION

The frequency of HIV testing among TB patients remained low at the university hospital providing TB and HIV care in Taiwan from 2000 to 2006. Among those tested for HIV infection, age < 50 years, male gender and presentation of extrapulmonary TB were associated with HIV infection.

Personal and societal health quality lost to tuberculosis

BACKGROUND

In developed countries, tuberculosis is considered a disease with little loss of Quality-Adjusted Life Years (QALYs). Tuberculosis treatment is predominantly ambulatory and death from tuberculosis is rare. Research has shown that there are chronic pulmonary sequelae in a majority of patients who have completed treatment for pulmonary tuberculosis (PTB). This and other health effects of tuberculosis have not been considered in QALY calculations. Consequently both the burden of tuberculosis on the individual and the value of tuberculosis prevention to society are underestimated. We estimated QALYs lost to pulmonary TB patients from all known sources, and estimated health loss to prevalent TB disease.

METHODOLOGY/PRINCIPAL FINDINGS

We calculated values for health during illness and treatment, pulmonary impairment after tuberculosis (PIAT), death rates, years-of-life-lost to death, and normal population health. We then compared the lifetime expected QALYs for a cohort of tuberculosis patients with that expected for comparison populations with latent tuberculosis infection and without tuberculosis infection. Persons with culture-confirmed tuberculosis accrued fewer lifetime QALYs than those without tuberculosis. Acute tuberculosis morbidity cost 0.046 QALYs (4% of total) per individual. Chronic morbidity accounted for an average of 0.96 QALYs (78% of total). Mortality accounted for 0.22 QALYs lost (18% of total). The net benefit to society of averting one case of PTB was about 1.4 QALYs.

CONCLUSIONS/SIGNIFICANCE

Tuberculosis, a preventable disease, results in QALYs lost owing to illness, impairment, and death. The majority of QALYs lost from tuberculosis resulted from impairment after microbiologic cure. Successful TB prevention efforts yield more health quality than previously thought and should be given high priority by health policy makers. (Refer to Abstracto S1 for Spanish language abstract).

The biosocial dynamics of tuberculosis

The declaration by the WHO of tuberculosis as a 'global emergency' illustrates the paradox of tuberculosis. The treatment of this disease is a good example of 'evidence-based medicine', having been fine-tuned by numerous clinical trials. Modern short-course anti-tuberculosis therapy is among the most effective and cost-effective ways of saving and prolonging human life; yet, this disease is more prevalent today than in the days before the advent of effective therapy and is currently the cause of one in seven deaths and one in four preventable deaths among young adults. It would seem that something has gone seriously wrong and, to shed light on the cause, it is necessary to take a very broad historical look at the changing trends in the behaviour of the disease in communities worldwide and the attitudes of the various communities to the disease in their midst, not just to understand past mistakes, but to make sure we do not make the same mistakes now and in the future.

What are the costs of suspected but not reported tuberculosis?

PURPOSE

Little is known regarding patients suspected, but not proven, to have tuberculosis before meeting reporting requirements. These patients generate unmeasured tuberculosis costs to the health care system. Elimination efforts are undervalued without fully quantifying the burden of tuberculosis. This may lead to decreased support and resurgence of this disease. This report provides a preliminary quantification of these costs.

METHODS

We used acid-fast bacillus (AFB) cultures completed as a proxy to estimate the number of patients with suspected tuberculosis who are never reported. We collected data on the number of AFB tests conducted in Tarrant County, TX, for calendar year 2002. We excluded all tests positive for Mycobacterium tuberculosis or secondary to growth of mycobacteria not M tuberculosis. We considered all AFBs conducted on an individual within 90 days to be single diagnostic episodes. We measured the number of diagnostic episodes, number of AFBs, number of AFBs meeting inclusion criteria, estimated cost incurred by testing, and individuals affected.

RESULTS

The Tarrant County hospitals sampled completed 6935 AFB cultures on an inpatient volume of 142,356 patients. One hundred ninety-three cultures confirmed tuberculosis or other mycobacteria, and 6742 AFBs were collected on persons suspected, but not proved, to have tuberculosis at an estimated $114.06 per culture. The total cost of eliminating tuberculosis as a cause of illness was $768,993. Laboratory costs for each patient with suspected, but not confirmed, tuberculosis averaged $364.11. One hundred forty-eight AFB cultures costing $16,830 were needed to confirm one case of tuberculosis.

CONCLUSIONS

The suspicion of tuberculosis incurs significant burdens and cost in the US health care system. More fully valuing tuberculosis elimination is important for tuberculosis management and will help maintain support for tuberculosis elimination.

Epidemiology of Tuberculosis in the United States

After decades of decline, an unprecedented resurgence in tuberculosis occurred in the late 1980s and early 1990s. Deterioration of tuberculosis program infrastructure, the HIV/AIDS epidemic, drug-resistant tuberculosis, and tuberculosis among foreign-born persons contributed to the resurgence. Since then, tuberculosis case numbers have declined, but the decline in 2003 was the smallest since the resurgence. Key challenges remain, and efforts must focus on identifying and targeting interventions for high-risk populations, active involvement in the global effort against tuberculosis, developing new tools, and maintaining adequate resources.

Jacobson v Massachusetts: it's not your great-great-grandfather's public health law

Jacobson v Massachusetts, a 1905 US Supreme Court decision, raised questions about the power of state government to protect the public's health and the Constitution's protection of personal liberty. We examined conceptions about state power and personal liberty in Jacobson and later cases that expanded, superseded, or even ignored those ideas. Public health and constitutional law have evolved to better protect both health and human rights. States' sovereign power to make laws of all kinds has not changed in the past century. What has changed is the Court's recognition of the importance of individual liberty and how it limits that power. Preserving the public's health in the 21st century requires preserving respect for personal liberty.

Tuberculosis: medical management update

Tuberculosis (TB) is an infectious chronic disease. After decades of steadily declining prevalence, the disease has reemerged in the last 5 years. Symptoms of TB are mild and not specific and can be classified as either systemic or localized to target organs. Microscopic examination of the sputum remains an inexpensive and rapid way to identify highly infectious patients. Four different antimicrobial agents-rifampin, ethambutol, pirazinamide, and isoniazid-form the basis of currently recommended antituberculosis therapy. Tuberculosis could be an occupational risk for health care workers. Dentists must be involved in the health promotion and early detection of TB.

The TB epidemic from 1992 to 2002

In 1992, less than 20 countries were implementing a sound TB control strategy. At the same time, TB was being resurrected as a major public health problem world-wide after two decades of neglect. Awareness of upward trends in the industrialized countries and MDR-TB outbreaks in large cities were driving forces behind the re-emergence of TB in the international health agenda. New evidence, and consequent estimates, suggested that the situation in developing countries, especially in sub-Saharan Africa, was deteriorating rapidly. Similarly, major increases were observed in the former USSR. It was estimated that some 7-8 million new cases and 2-3 million deaths were occurring annually in the world. The global targets of reaching 85% cure rates and 70% case detection among infectious cases were established by the World Health Assembly in 1991. Both the WHO declaration of TB as a global emergency in 1993 and the launch of the five-element DOTS strategy in 1994-1995 resulted in countries adopting DOTS in encouraging numbers. In fact, in 2000, 148 countries including all 22 highest burden countries (HBC) responsible for 80% of cases world-wide, had adopted the new DOTS strategy. Nevertheless, progress in case detection remained slow due to incomplete geographical coverage or need to widen detection and notification capacity with innovative schemes. The major constraints to TB control became increasingly clear, and a global Stop TB Partnership was eventually established to address such constraints. A Global DOTS Expansion Plan revealed the needs and the gaps to achieve the global targets in 2005. Today, in 2002, the top priority remains that of expanding DOTS, as rapidly as possible, using a number of new approaches to increase case detection and notification while maintaining high cure rates. These must involve collaboration with the private sector and communities, as well as strengthening of primary care services. Similarly, crucial is the rapid identification of solutions to TB/HIV and MDR-TB.

Tuberculosis trends in the United States, 1992-2001

At the time of the last world congress on tuberculosis (TB) in 1992, the United States (US) was experiencing an unprecedented resurgence of TB. Since the mid-1950s, TB incidence had been steadily decreasing, until 1984 when this longstanding trend was reversed. The annual national total of TB cases continued to increase and peaked in 1992 with 26,673 TB cases reported (10.5 TB cases per 100,000 population). A prompt and formidable response from local, state, and federal governments helped curb the resurgence. From 1992 to 2001, total TB incidence decreased by 40% to an all-time low of 15,989 TB cases reported in 2001. The decrease in TB cases from 2000 to 2001, however, was the smallest (2.4%) since the resurgence a decade ago. This report will briefly review the trends and factors associated with the TB resurgence in the late 1980s and early 1990s, and provide a detailed description of specific TB trends in the US between 1992 and 2001.

The politics of 'branding' in policy transfer: the case of DOTS for tuberculosis control

How and why policies are transferred between countries has attracted considerable interest from scholars of public policy over the last decade. This paper, based on a larger study, sets out to explore the processes involved in policy transfer between international and national levels. These processes are illustrated by looking at a particular public health policy--DOTS for the control and treatment of tuberculosis. The paper demonstrates how, after a long period of neglect, resources were mobilised to put tuberculosis back on international and national public policy agendas, and then how the policy was 'branded' and marketed as DOTS, and transferred to low and middle income countries. It focuses specifically on international agenda setting and policy formulation, and the role played by international organisations in those processes. It shows that policy communities, and particular individuals within them, may take political rather than technical positions in these processes, which can result in considerable contestation. The paper ends by suggesting that while it is possible to raise the profile of a policy dramatically through branding and marketing, success also depends on external events providing windows of opportunity for action. Second, it warns that simplifying policy approaches to 'one-size-fits-all' carries inherent risks, and can be perceived to harm locally appropriate programmes. Third, top-down internationally driven policy changes may lead to apparent policy transfer, but not necessarily to successfully implemented programmes.

Development of a new sensitive and efficient multiplex polymerase chain reaction (PCR) for identification and differentiation of different mycobacterial species

For early detection and species differentiation of mycobacteria, polymerase chain reaction (PCR) techniques are currently in wide use. However, individual techniques using amplification of different targets with appropriate primers still have some limitations, which have to be overcome. The ideal technique would use DNA sequences which should be present in all mycobacteria and absent in others and would be able to discriminate one species from the other, as non-tuberculous mycobacteria (NTM) are on rise in terms of frequency of detection. We developed a multiplex PCR based on amplification of 165, 365 and 541 bp target fragments of unrelated genes, hsp 65 coding for 65 kDa antigen, dnaJ gene of mycobacteria and insertion element IS 6110 of Mycobacterium tuberculosis, respectively. This multiplex PCR was tested over 5 years from 1996 to 2001 with 411 clinical specimens from suspected cases of tuberculosis and mycobacterioses and compared with standard laboratory techniques. The multiplex PCR was positive for 379 cases compared with 280 cases by standard techniques (P < 0.0001). It could distinguish between strains of the M. tuberculosis complex and NTM; the results are comparable with standard techniques. Thus the multiplex PCR can be useful in early detection, species differentiation and epidemiology.

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.

Limited transmission of multidrug-resistant tuberculosis despite a high proportion of infectious cases in Los Angeles County, California

Preventing transmission of multidrug-resistant tuberculosis is critical because of treatment toxicity, cost, and the lack of effective therapy for latent infection. We attempted to determine the extent of transmission in Los Angeles County by comparing relatedness of multidrug-resistant tuberculosis cases using restriction fragment length polymorphism and by cross-matching contact information to the Tuberculosis Registry. Strain typing was done on isolates of 102 pulmonary multidrug-resistant cases identified between August 1993 and 1998. Seventy-one (70%) of the cases had cavitary lesions on chest radiograph, and 94 (92%) had sputa smear-positive for acid fast bacilli. Fifteen (15%) of the cases were known to be infected with human immunodeficiency virus. Four molecular clusters of two cases each and one closely related pair were identified among the 102 cases; contact investigation successfully identified all clusters but one. Among 946 contacts identified and cross-matched with the county's Tuberculosis Registry, one secondary case due to drug-resistant Mycobacterium bovis was found. To summarize, a very high proportion of pulmonary multidrug-resistant tuberculosis cases in Los Angeles County were infectious. Molecular strain typing indicated limited spread of disease, although it underestimated transmission compared with contact investigation. We believe aggressive surveillance and case management were critical to limiting the spread of multidrug- resistant tuberculosis.

Missed opportunities? Coercion or commitment: policies of prevention

The DOTS strategy (directly observed therapy, short course) has been the cornerstone of international TB control policy since the early 1990s. This strategy has provided the international community with an advocacy tool to harness funds for TB as well as a method for helping country programs to achieve high cure rates for TB. But as much as the strategy is seen as successful by some, it is perceived as unsuccessful by others. This paper looks at the results of the introduction of DOTS into control programs and discusses research relating to direct observation of treatment. It asks how policies like DOTS are created, and how they are administered and transferred from the international to the national and finally to the local level. The discipline of public health policy is used to interrogate the creation and history of the DOTS strategy in order to find ways of aiding the transfer of the policy to national and local levels. Finally, the paper asks whether the concepts of "control" and "elimination" continue to be useful in the management of infectious diseases. We ask whether it is time to change the perspective to policies that focus more on the context of implementation and the importance of the development of care, integration, and flexibility rather than cure, targets, and short-term solutions.

Tuberculosis in the twentieth century: time-series mortality in São Paulo, Brazil, 1900-97

The objective of this study was to characterize tuberculosis mortality trends in the Municipality of São Paulo, Brazil, from 1900 to 1997. Standardized tuberculosis mortality rates and proportional mortality ratios were calculated and stratified by gender and age group based on data provided by government agencies. These measures were submitted to time-series analysis. We verified distinct trends: high mortality and a stationary trend from 1900 to 1945, a heavy reduction in mortality (7.41% per year) from 1945 to 1985, and a resumption of increased mortality (4.08% per year) from 1985 to 1995. In 1996 and 1997 we observed a drop in tuberculosis mortality rates, which may be indicating a new downward trend for the disease. The period from 1945 to 1985 witnessed a real reduction in tuberculosis, brought about by social improvements, the introduction of therapeutic resources, and expansion of health services. Recrudescence of tuberculosis mortality from 1985 to 1995 may reflect the increasing prevalence of Mycobacterium and HIV co-infection, besides loss of quality in specific health programs.

Incidência e fatores de risco para tuberculose em Pelotas, uma cidade do Sul do Brasil

Objetivou-se medir a incidência e avaliar fatores de risco para tuberculose, em adultos de Pelotas. Os casos foram detectados na "Secretaria Municipal da Saúde e Bem Estar" (Centro de Saúde), no período de junho de 1994 a junho de 1995. Concomitante, controles populacionais, pareados por sexo e idade, eram sorteados e aplicado o mesmo questionário aos casos e controles. A incidência notificada de tuberculose foi de 72,4/100.000 habitantes. A análise estatística bruta mostrou os seguintes odds ratios: 10,8 (classe social E), 5,4 (renda familiar < 1 salário mínimo) e 6,6 (analfabetos). O risco em pessoas de cor não branca foi de 4,7; aglomeração e contato com tuberculose apresentaram respectivamente riscos de 3,1 e 5,3. Alcoolismo mostrou um risco de 4,3 e os portadores de doenças associadas à tuberculose um risco de 3,6; as variáveis história de diabete e moradia próxima a pedreiras não se mostraram associadas com tuberculose. Os trabalhadores de pedreiras apresentaram um risco de 4,0. Na análise por regressão logística condicional, as seguintes variáveis permaneceram, após ajuste para fatores de confusão, significativamente associadas com tuberculose: contato com tuberculose (OR=8,2), alcoolismo (OR=4,0), trabalho em pedreira (OR=4,7) e cor não branca (OR=3,1). Conclui-se que a incidência de tuberculose em Pelotas é muito elevada e que a maioria dos fatores de risco são passíveis de prevenção ou redução.

Tuberculin skin testing of hospitalized patients

OBJECTIVES

We sought to define the prevalence of tuberculin skin test (TST) positivity in a group of newly hospitalized patients, to identify risk factors for positive tests, and to examine the impact of testing on infection control practices.

DESIGN

Unblinded cohort study over 5 days in July 1992.

SETTING

A 1,000-bed university-affiliated hospital.

PATIENTS

All patients admitted (excluding obstetric patients and newborns) were interviewed. Patients without a history of tuberculosis (TB) or a positive TST were offered a TST with Candida and tetanus controls.

RESULTS

Of 346 patients offered the test, 21 (6%) had a prior history of TB or a positive TST, and 36 (10%) declined to participate; 279 of the remaining 289 completed the study. Anergy was demonstrated in 94 (33.7%) of 279 patients. New positive TSTs were identified in 19 (10.3%) of 185 nonanergic patients. Of the 19 TST-positive patients, 6 (32%) had infiltrates on chest radiographs and were evaluated for active TB. One patient was treated empirically for active TB, and five received isoniazid prophylaxis. Risk factors for a new positive TST included age (odds ratio [OR], 1.56 per decade of life; P = .021), African American race (OR, 4.81; P = .008), alcohol abuse (OR, 5.53; P = .005), and peptic ulcer disease (OR, 4.53; P = .017). Risk factors for anergy included admission to a surgical service (OR, 2.1; P = .006), current use of steroids (OR, 2.65; P = .005), and human immunodeficiency virus (HIV) infection (OR, undefined; P = .034).

CONCLUSIONS

Despite a high rate of anergy, routine tuberculin skin testing identified a substantial number of patients with TB infection who might otherwise have gone unrecognized.

[HIV/tuberculosis co-infection: a request for a better surveillance]

The increasing endemicity of tuberculosis resulting from causes such as immigration, poverty, a declining public health infrastructure and co-infection by HIV/Mycobacterium tuberculosis, is leading to a change in tuberculosis control programmes. One of the main reasons for the resurgence of tuberculosis is HIV infection--the risk of tuberculosis is greater in HIV patients than in the majority of the population as can be seen from numerous research projects. The need for systematic testing for HIV infection in all tuberculosis patients by undertaking confidential HIV tests on admission to a tuberculosis programme is brought out. This measure would increase the number of cases diagnosed and provide data for better surveillance of the co-infection.

Tuberculosis. Part I

Tuberculosis has been a disease of human beings for thousands of years. In recent times it has waxed to become the feared White Plague of the eighteenth and nineteenth centuries and waned under the impact of effective chemotherapy until its elimination seemed possible by the early twenty-first century. The resurgence of tuberculosis in the past 10 to 15 years, caused by unanticipated events such as the appearance of the human immunodeficiency virus and deteriorating social conditions, also brought with it the problem of multiple drug resistance. Control measures such as tuberculin skin testing, perhaps somewhat forgotten when tuberculosis seemed to be a disease of the past, again became first-line defenses against spread of the disease. Environmental controls must be well understood and used effectively. Diagnosis of tuberculosis requires knowledge of the strengths and shortcomings of the various diagnostic methods and experience in their use. Practitioners are cautioned to remember that no diagnostic method, by itself, can be relied on to confirm or rule out tuberculosis. Well-tested diagnostic methods of chest radiograph, tuberculin skin testing, smear, and culture have been recently supplemented by rapid diagnostic tests based on amplification of bacterial RNA and DNA. More invasive diagnostic methods are sometimes required to diagnose extrapulmonary disease. Two-drug up to seven-drug therapy may be indicated for a case of tuberculosis, depending on evidence of the presence of multiple drug resistance. Duration of treatment can range from 6 to 12 months, also depending on identification of drug-sensitive or drug-resistant organisms. Failure of compliance can be a significant problem in patients who are homeless, or drug abusers, or who for various reasons cannot or will not complete a course of therapy. Directly observed therapy is strongly recommended for these patients, and for assistance in its administration the physician must cooperate with the local or state health department. The health department also must be notified whenever a case of tuberculosis is identified.

Health outcomes and infectious disease control

With the development of improved health systems, antibiotics and vaccines throughout the 20th century, the prospects of control of infectious diseases improved. During the same time-frame, an approach to disease control was developed which used the health outcomes resulting from various interventions to choose, guide and modify those interventions. Despite these major advances in the control of diseases, infectious diseases have (with occasional exceptions) not only continued to occur but in many instances the situation had deteriorated with the emergence and re-emergence in recent years of a range of infectious diseases. In this paper we consider why infectious disease control has not benefited from the move towards a health outcomes approach, why infectious disease control might benefit from such a move, and the differences between infectious and non-infectious diseases when considering health outcomes. We follow-up with some practical approaches to the use of health outcomes. We argue that appropriate use of health outcomes when planning and evaluating infectious disease control programs will improve human health.

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.