Increase In Incidence Of Tuberculosis Research Articles

The resurgence of tuberculosis in the Republic of Ireland: Perceptions and reality

Tuberculosis remained a very significant cause of death in Ireland until the mid-20th century and still occupies a prominent position in the folk memory. As I show with reference to recent Irish media coverage, the global resurgence of tuberculosis is therefore viewed with concern in Ireland. Using data collated by the Health Protection Surveillance Centre between 1998 and 2005 however, I show that the recent increase in tuberculosis incidence in Ireland is less than is popularly perceived. This increase is largely associated with economic immigrants attracted to Ireland by the ‘Celtic Tiger’ economic boom, but there is little evidence to suggest that this has had a negative impact on the Irish-born population. Drug resistance is still a small but growing problem. Whilst vigilance is required, it is argued that the recent increase does not at present indicate a likely return to the situation in the mid-20th century.

Literature in Brief

Stuckler D, Basu S, McKee M, King L. Mass incarceration can explain population increases in TB and multidrug-resistant TB in European and central Asian countries. Proceedings of the National Academy of Sciences. 2008; 105(36):13280–5. Thomas JC, Torrone E. Incarceration as Forced Migration: Effects on Selected Community Health Outcomes. Prisons and Health. 2008; 98(9 Suppl): S181–4. These two articles both describe detrimental effects of increasing incarceration rates on population health. The Stuckler article evaluated the effect of increasing rates of incarceration on tuberculosis (TB) in Eastern European and Central Asian countries. They found that each percentage rise in the sentencing rate was associated with a 0.34% increase in TB incidence. The sentencing rates rose 60% from 1991 to 2002 in the countries surveyed. The net effect of this increase, after controlling for multiple variables, was a 20% rise in TB incidence, which accounted for three-fifths of the total 35% increase in TB incidence during that time frame. The authors conclude that more than the absolute number of prisoners, the rate of prison growth is the largest determinant of TB infection. The Thomas article examined the correlation between rates of incarceration and rates of sexually transmitted diseases (STDs) and teen pregnancies in North Carolina from 1995 to 2002. They found that even after controlling for age, race, and poverty, STDs and teen pregnancies consistently increased with rising incarceration rates. Most notably, a county with a prison population rate in the 75th percentile had a 32% increase in teen pregnancies when compared to a county with a prison population rate in the 25th percentile. The authors argue that high rates of incarceration destabilize communities. With men ten times as likely to be imprisoned, incarceration lowers the ratio of men to women which has been shown to increase rates of teen pregnancy, syphilis, and gonorrhea in other studies.

Effects of duration of HIV infection and secondary tuberculosis transmission on tuberculosis incidence in the South African gold mines

HIV increases the risk of tuberculosis directly, through immunosuppression, and indirectly, through onward transmission of Mycobacterium tuberculosis from the increased caseload. We assess the contribution of these two mechanisms by time since seroconversion to HIV. The incidence of new pulmonary tuberculosis was estimated in a retrospective cohort study of South African gold miners over 14 years. HIV tests were done in random surveys in 1992-1993, and in clinics. One thousand nine hundred fifty HIV positive men with seroconversion intervals of less than 3 years were identified and linked to medical, demographic and occupational records. They were compared with men who were HIV-negative in a survey, with no later evidence of HIV. Analyses were censored when men were diagnosed with tuberculosis, died or left the mine. Tuberculosis incidence rose soon after HIV infection, reaching 1.4/100 person-years (95% confidence interval 1.1-1.9) within 2 years, and 10.0/100 person-years (95% confidence interval 6.5-15.5) at 10 or more years. By 11 years from seroconversion, nearly half the men had had tuberculosis. Among 5702 HIV-negative men, tuberculosis incidence was 0.48/100 person-years (95% confidence interval 0.33-0.70) in 1991-1993 and doubled over the period of the study (after adjusting for age). Age-adjusted model estimates suggest that half the increase in tuberculosis incidence by time since HIV infection was attributable to increasing incidence over calendar period--the indirect effect. For the first time, we have shown that the increase in tuberculosis risk by time since seroconversion reflects both direct effects of HIV increasing susceptibility, and indirect effects due to onward transmission. Innovative and sustained public health measures are needed to reduce Mycobacterium tuberculosis transmission.

Mass incarceration can explain population increases in TB and multidrug-resistant TB in European and central Asian countries

Several microlevel studies have pinpointed prisons as an important site for tuberculosis (TB) and multidrug-resistant TB in European and central Asian countries. To date, no comparative analyses have examined whether rises in incarceration rates can account for puzzling differences in TB trends among overall populations. Using longitudinal TB and cross-sectional multidrug-resistant TB data for 26 eastern European and central Asian countries, we examined whether and to what degree increases in incarceration account for differences in population TB and multidrug-resistant TB burdens. We find that each percentage point increase in incarceration rates relates to an increased TB incidence of 0.34% (population attributable risk, 95% C.I.: 0.10-0.58%, P < 0.01), after controlling for TB infrastructure; HIV prevalence; and several surveillance, economic, demographic, and political indicators. Net increases in incarceration account for a 20.5% increase in TB incidence or nearly three-fifths of the average total increase in TB incidence in the countries studied from 1991 to 2002. Although the number of prisoners is a significant determinant of differences in TB incidence and multidrug-resistant TB prevalence among countries, the rate of prison growth is a larger determinant of these outcomes, and its effect is exacerbated but not confounded by HIV. Differences in incarceration rates are a major determinant of differences in population TB outcomes among eastern European and central Asian countries, and treatment expansion alone does not appear to resolve the effect of mass incarceration on TB incidence.

International Monetary Fund Programs and Tuberculosis Outcomes in Post-Communist Countries

BackgroundPrevious studies have indicated that International Monetary Fund (IMF) economic programs have influenced health-care infrastructure in recipient countries. The post-communist Eastern European and former Soviet Union countries experienced relatively similar political and economic changes over the past two decades, and participated in IMF programs of varying size and duration. We empirically examine how IMF programs related to changes in tuberculosis incidence, prevalence, and mortality rates among these countries.Methods and FindingsWe performed multivariate regression of two decades of tuberculosis incidence, prevalence, and mortality data against variables potentially influencing tuberculosis program outcomes in 21 post-communist countries for which comparative data are available. After correcting for confounding variables, as well as potential detection, selection, and ecological biases, we observed that participating in an IMF program was associated with increased tuberculosis incidence, prevalence, and mortality rates by 13.9%, 13.2%, and 16.6%, respectively. Each additional year of participation in an IMF program was associated with increased tuberculosis mortality rates by 4.1%, and each 1% increase in IMF lending was associated with increased tuberculosis mortality rates by 0.9%. On the other hand, we estimated a decrease in tuberculosis mortality rates of 30.7% (95% confidence interval, 18.3% to 49.5%) associated with exiting the IMF programs. IMF lending did not appear to be a response to worsened health outcomes; rather, it appeared to be a precipitant of such outcomes (Granger- and Sims-causality tests), even after controlling for potential political, socioeconomic, demographic, and health-related confounders. In contrast, non-IMF lending programs were connected with decreased tuberculosis mortality rates (−7.6%, 95% confidence interval, −1.0% to −14.1%). The associations observed between tuberculosis mortality and IMF programs were similar to those observed when evaluating the impact of IMF programs on tuberculosis incidence and prevalence. While IMF programs were connected with large reductions in generalized government expenditures, tuberculosis program coverage, and the number of physicians per capita, non-IMF lending programs were not significantly associated with these variables.ConclusionsIMF economic reform programs are associated with significantly worsened tuberculosis incidence, prevalence, and mortality rates in post-communist Eastern European and former Soviet countries, independent of other political, socioeconomic, demographic, and health changes in these countries. Future research should attempt to examine how IMF programs may have related to other non-tuberculosis–related health outcomes.

HIV Infection and Multidrug‐Resistant Tuberculosis—The Perfect Storm

Multidrug-resistant (MDR) tuberculosis (TB) has emerged as a global epidemic, with ~425,000 new cases estimated to occur annually. The global human immunodeficiency virus (HIV) infection epidemic has caused explosive increases in TB incidence and may be contributing to increases in MDR-TB prevalence. We reviewed published studies and available surveillance data evaluating links between HIV infection and MDR-TB to quantify convergence of these 2 epidemics, evaluate the consequences, and determine essential steps to address these epidemics. Institutional outbreaks of MDR-TB have primarily affected HIV-infected persons. Delayed diagnosis, inadequate initial treatment, and prolonged infectiousness led to extraordinary attack rates and case-fatality rates among HIV-infected persons. Whether this sequence occurs in communities is less clear. MDR-TB appears not to cause infection or disease more readily than drug-susceptible TB in HIV-infected persons. HIV infection may lead to malabsorption of anti-TB drugs and acquired rifamycin resistance. HIV-infected patients with MDR-TB have unacceptably high mortality; both antiretroviral and antimycobacterial treatment are necessary. Simultaneous treatment requires 6-10 different drugs. In HIV-prevalent countries, TB programs struggle with increased caseloads, which increase the risk of acquired MDR-TB. Surveillance data suggest that HIV infection and MDR-TB may converge in several countries. Institutional outbreaks, overwhelmed public health programs, and complex clinical management issues may contribute to the convergence of the MDR-TB and HIV infection epidemics. To forestall disastrous consequences, infection control, rapid case detection, effective treatment, and expanded program capacity are needed urgently.

The impact of the HIV epidemic on tuberculosis transmission in Tanzania

To assess the impact of the HIV epidemic on tuberculosis transmission in Tanzania by estimating the trend in annual risk of tuberculosis infection (ARTI) over the period 1983-2003. Tuberculin survey among school children aged 6-14 years, randomly selected by cluster sampling. Primary outcome was the ARTI among children without a BCG vaccination scar. To obtain time trends, data were reanalysed from three previous surveys carried out at intervals of 5 years since 1983, using identical methods and definitions. Of 96,226 children included in the analysis (74% of those enrolled), 10,239 (11%) had no BCG scar. The ARTI was 0.68% (95% confidence interval 0.55-0.81). Despite a doubling of notification rates of smear-positive tuberculosis since 1983, this represents an average annual decline since the first survey of 2.7% (P < 0.001). The declining trend in ARTI was observed in 17 of 20 regions, with no association between this trend and region-specific prevalence of HIV infection among patients with tuberculosis (P = 0.575). A similar decline in ARTI was observed among children with a BCG scar and for various ways of estimating the prevalence of tuberculosis infection from the distribution of skin test reactions. Despite substantial increases in tuberculosis incidence, the overall population-level effect of the HIV epidemic on tuberculosis transmission in Tanzania has been limited. This suggests that in the presence of a strong control programme, the HIV epidemic has limited impact on tuberculosis transmission.

Faut-il arrêter le BCG ?

The current epidemiological situation of tuberculosis in France makes it necessary to re-assess the relevancy of the current BCG policy. It is close to the thresholds proposed internationally to consider the discontinuation of vaccination programs using BCG. Both the literature, specially experiences from European countries, and the analysis carried out on French data are in favour of an extremely limited impact of BCG revaccination of tuberculino-negative children. From these same sources, it can be anticipated that interruption of all BCG activities would result in an increase in tuberculosis incidence, affecting mainly high risks populations. The importance of this increase depends on the hypothesis made on BCG effectiveness. The National Technical Committees on Vaccination and Infectious Diseases have recommended in June 2002 the discontinuation of BCG revaccination and systematic tuberculin testing and should issued a definitive statement on November 2002. The decision regarding primo-vaccination needs, as a pre-requisite, a risk-benefit analysis taking into consideration adverse aspects of BCG vaccination, and an analysis of the feasibility and acceptability of various potential modifications in the population targeted by the BCG.

Solitary tuberculoma of the cerebellopontine angle: a rare presentation

Central nervous system tuberculoma presenting as a solitary mass in an extrinsic location is rare. Due to the increase in incidence of tuberculosis in the western world, there is a corresponding increase in CNS tuberculosis. Cerebellopontine angle tumours are most commonly acoustic schwannomas or meningiomas. Radiosurgery as a primary modality of treatment for many CNS masses without prior pathological diagnosis is increasing in popularity. This report shows that a mass in the CP angle can closely mimic a tumour radiologically and inappropriate radiation treatment was avoided after surgery. Histopathological examination proved it to be a tuberculoma. Awareness of this rare presentation of a solitary tuberculoma in the CP angle is emphasised.

Can tuberculosis be controlled?

Tuberculosis (TB) is nearly 100% curable. However, the ability of medical and public health interventions to control TB, particularly in developing countries, is often doubted. We reviewed data for the amenability of TB to control. We considered separately control of deaths, prevalence, rate of infection and incidence. Tuberculosis mortality can be reduced by more than 80% in less than 5 years. The prevalence of TB can be reduced by 30% or more annually; sustained annual decreases of 17% have been documented in a developing country. The TB infection rate can be reduced by 15% annually. In the absence of human immunodeficiency virus (HIV), TB incidence can be decreased by as much as 25% per year and up to 10% annually in developing countries. A high prevalence of untreated HIV infection in the adult population of a developing country will inevitably result in a significant increase in TB incidence despite optimal use of currently available technologies. Tuberculosis can be controlled if appropriate policies are followed, effective clinical and public health management is ensured, and there are committed and co-ordinated efforts from within and outside the health sector. However, in the context of a large epidemic of AIDS, TB incidence will inevitably increase. By 2001, less than 30% of global TB cases were reported to have received effective diagnosis, treatment and monitoring. Rapid expansion of effective TB control services is urgently required, both to avert the continued high burden of morbidity and mortality from TB and because of the HIV pandemic.

Neighborhood poverty and the resurgence of tuberculosis in New York City, 1984-1992.

The resurgence of tuberculosis (TB) in NewYork City has been attributed to AIDS and immigration; however, the role of poverty in the epidemic is unclear. We assessed the relation between neighborhood poverty and TB at the height of the epidemic and longitudinally from 1984 through 1992. Census block groups were used as proxies for neighborhoods. For each neighborhood, we calculated TB and AIDS incidence in 1984 and 1992 with data from the Bureaus of Tuberculosis Control and AIDS Surveillance and obtained poverty rates from the census. For 1992, 3,343 TB cases were mapped to 5,482 neighborhoods, yielding a mean incidence of 46.5 per 100,000. Neighborhood poverty was associated with TB (relative risk = 1.33; 95% confidence interval = 1.30, 1.36 per 10% increase in poverty). This association persisted after adjustment for AIDS, proportion foreign born, and race/ethnicity. Neighborhoods with declining income from 1980 to 1990 had larger increases in TB incidence than did neighborhoods with increasing income. Leading up to and at the height of the TB epidemic in New York City, neighborhood poverty was strongly associated with TB incidence. Public health interventions should target impoverished areas.

Epidemiology of Tuberculosis in HIV-infected Patients in Denmark

Denmark is an area of low incidence of HIV and tuberculosis (TB). The number of newly reported cases of HIV has been stable during the 1990s, whereas the number of TB cases has doubled in Denmark in the past decade, mainly due to immigration. However, among native Danes the incidence of TB has increased in the younger age groups, indicating more newly infected persons. This study was performed in order to assess the impact of the HIV epidemic and immigration on TB incidence among native Danes. The study was also designed to reveal transmission patterns of TB among HIV-positive patients. Data from HIV-TB co-infected patients identified in the national registers of TB and AIDS from 1992-95 were collected retrospectively from medical records. Restriction fragment length polymorphism (RFLP) analyses of TB isolates from co-infected patients were compared with all patterns registered in the nationwide Danish RFLP database (approximately 1,700 patients). Sixty-seven co-infected patients were identified, 26 Danes and 41 immigrants, representing only 4% of all TB cases during the study period. Danish co-infected patients were part of a cluster, i.e. they had a RFLP-pattern identical to a pattern in the national RFLP database, more often than immigrants (83% vs. 45%, p < 0.005). In only 2 cases were co-infected Danes and immigrants part of the same cluster. Danish HIV-TB co-infected patients were more often intravenous drug users than were co-infected immigrants (p < 0.0005). In conclusion, we found no evidence to suggest that the increase in TB incidence among young Danes was caused by the HIV-epidemic or transmission from immigrants. TB among HIV-positive Danes is most often due to recent infection. The patients often belong to a subpopulation living in Copenhagen characterized by intravenous drug use.

Prospects for worldwide tuberculosis control under the WHO DOTS strategy

WHO advocates the use of directly observed treatment with a short-course drug regimen as part of the DOTS strategy, but the potential effect of this strategy worldwide has not been investigated. We developed an age-structured mathematical model to explore the characteristics of tuberculosis control under DOTS, and to forecast the effect of improved case finding and cure on tuberculosis epidemics for each of the six WHO regions. In countries where the incidence of tuberculosis is stable and HIV-1 absent, a control programme that reaches the WHO targets of 70% case detection and 85% cure would reduce the incidence rate by 11% (range 8-12) per year and the death rate by 12% (9-13) per year. If tuberculosis has been in decline for some years, the same case detection and cure rates would have a smaller effect on incidence. DOTS saves a greater proportion of deaths than cases, and this difference is bigger in the presence of HIV-1. HIV-1 epidemics cause an increase in tuberculosis incidence, but do not substantially reduce the preventable proportion of cases and deaths. Without greater effort to control tuberculosis, the annual incidence of the disease is expected to increase by 41% (21-61) between 1998 and 2020 (from 7.4 million to 10.6 million cases per year). Achievement of WHO targets by 2010 would prevent 23% (15-30) or 48 million cases by 2020. The potential effect of chemotherapy (delivered as DOTS) on tuberculosis is greater in many developing countries now than it was in developed countries 50 years ago. To exploit this potential, case detection and cure rates urgently need to be improved in the main endemic areas.

Imaging of tuberculosis--experience from 503 patients. I. Tuberculosis of the chest.

To give an overview of 503 patients with tuberculosis (TB) and to describe the radiologic findings of chest TB. A total of 503 patients with proven TB were reviewed; 266 had chest involvement. Lung lesions were demonstrated in 214 patients. Infiltrates in the basal parts of the lungs or pleural effusion were often primarily mistaken for viral or bacterial infections. Consolidations within the lungs and pleural thickening were sometimes indistinguishable from malignancy. Positive culture of the sputum without lung lesions was encountered in 12 cases. Enlarged mediastinal lymph nodes were demonstrated in 67 cases, 35 without lesions in the lungs. The lymphadenopathy could be extensive, and both clinically and radiologically indistinguishable from lymphoma. Due to the present increase in incidence of TB and the fact that TB can mimic many other conditions, it is important that both clinicians and radiologists have TB high on the list for differential diagnoses.

Tuberculosis Makes a Comeback

Tuberculosis (TB) has plagued mankind for many centuries. In the past, the number of people affected with this potentially deadly disease declined, but there has been a recent dramatic increase in TB incidence. This increase is attributed largely to people who are coinfected with TB and HIV and to the development of resistant strains of Mycobacterium tuberculosis during the last decade. The US social infrastructure also has contributed to a rapid rise in TB cases due to adverse socioeconomic factors and an increase in the number of immigrants and people infected with HIV. This article gives a historical overview of TB; discusses its diagnosis, transmission and prevention modalities; and provides a case study about a TB-infected patient who required emergent surgical intervention.

Institutional Control Measures for Tuberculosis in the Era of Multiple Drug Resistance: ACCP/ATS Consensus Conference

Institutional Control Measures for Tuberculosis in the Era of Multiple Drug Resistance: ACCP/ATS Consensus Conference

CHILDHOOD TUBERCULOSIS IN THE BRONX.

The increased incidence of tuberculosis (TB) in New York has been linked with the AIDS epidemic and urban poverty. This study examined how household

HIV-1 seroprevalence in chest clinic and hospital tuberculosis patients in New York City, 1989–1991

To describe more fully HIV-1 and tuberculosis (TB) coinfection in TB patients attending New York City Department of Health chest clinics (1989-1991) and one inner-city hospital (1990-1991). An unlinked serosurvey using HIV-1-antibody testing of remnant blood specimens collected for routine medical purposes. A total of 1414 clinic and 856 hospital patients. HIV seropositivity and TB infection/disease. A total of 327 (23%) of the clinic patients were HIV-1-positive, with a significantly higher seroprevalence in men (29 versus 15%, P < 0.001) and in young and middle-aged adults aged 30-50 years (P < 0.001). HIV-1 prevalence by TB diagnostic class was: class 2 (purified protein derivative-positive and chest radiograph-negative), 11% (64 out of 570); class 3 (active disease), 34% (197 out of 582); class IV (old/inactive disease), 30% (39 out of 130). Of the hospital patients 487 (57%) were HIV-1-positive. HIV-1 seroprevalence was 55% for those who were identified or believed to be HIV-1-negative on admission as indicated on the medical chart. HIV-1 seroprevalence in the clinic population decreased initially, but later increased, although not to study onset levels. There is considerable overlap between the TB and HIV epidemics in New York City; a part of the increasing TB incidence may be independent of HIV coinfection. The control of TB will necessitate prompt diagnosis of TB and HIV-1, appropriate TB treatment and/or chemoprophylaxis, and a greater commitment to tackle the social conditions associated with the spread of the disease.

Failure of Tuberculosis Control

The dramatic increase in tuberculosis (TB) incidence¹is testimony to the failure of the United States to coordinate its medical care provision, disease surveillance, and societal will to consistently provide TB therapy and monitor TB control.²In this issue ofThe Journal, Bloch and colleagues³demonstrate a remarkable shift in the epidemiology of TB in the United States. In the 1970s, US health officials believed that indigenous TB was coming under control, its ultimate elimination possible with only an occasional case reactivating in the elderly. Transient increases in TB incidence were attributed to immigrants, such as the Indochinese refugees in the mid 1970s⁴and Philippine national World War II veterans in Hawaii in the 1990s.⁵These foreign cases brought with them the peril of drug resistance as a result of the indiscriminate and inconsistent use of TB medications in the immigrants' countries of origin. Bloch

Childhood tuberculosis in Sweden: An epidemiological study made six years after the cessation of general BCG vaccination of the newborn

General BCG vaccination of the newborn was started in Sweden in the 1940s and was stopped on April 1, 1975. The effect of this change in policy has been analysed in a study of children born in Sweden in 1969 or later and whose names were entered in the Central Tuberculosis Register from 1969 to 1980. A comparison was made between two groups of children: 1. children born in Sweden between April 1, 1969 and December 31, 1974 and who contracted tuberculosis during that period; all the children in this group were BCG-vaccinated ; 2. children born between April 1, 1975 and December 31, 1980 and who contracted tuberculosis during that period. Only one child in this group had been vaccinated. In the first group of vaccinated children 4 cases of pulmonary tuberculosis, one case of meningitis and one case of lymphadenitis were recorded. Among the unvaccinated children in the second group, 20 cases of pulmonary tuberculosis, one fatal case of miliary tuberculosis and two cases of meningitis were recorded. In addition 13 cases of mycobacterial lymph node disease and one case of skin granuloma were found, but these were considered likely to be caused by non-tuberculous mycobacterial infection. The incidence of pulmonary, miliary and meningeal tuberculosis was 8 times higher among children born to foreign parents (6.4 per 100 000 person-years) than among unvaccinated Swedish children (0.8 per 100 000). Despite the increase in incidence of tuberculosis which occurred after the cessation of vaccination of the newborn, the continued low incidence of tuberculosis in Swedish children up to and including 1980 does not justify the reintroduction of general BCG vaccination of the newborn in Sweden.