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Michael F Iademarco

Publications and source records attributed to Michael F Iademarco.

14 recordsLinked to original sources
PubMed2006

Tuberculosis among foreign-born persons in the United States: achieving tuberculosis elimination.

RATIONALE: In the United States, the number of annual reported cases of tuberculosis (TB) among U.S.-born persons declined by 62% from 1993 to 2004, but increased by 5% among foreign-born persons. Over half of all reported cases of TB in the United States occur among foreign-born persons, most of these due to activation of latent TB infection (LTBI). Current guidelines recommend targeting only foreign-born persons who entered the United States within the previous 5 yr for LTBI testing. OBJECTIVE: We sought to assess the epidemiologic basis for this guideline. METHODS: We calculated TB case rates among foreign-born persons, stratified by duration of United States residence and world region of origin. We determined the number of cases using 2004 U.S. TB surveillance data, and calculated case rates using population data from the 2004 American Community Survey. MEASUREMENTS AND MAIN RESULTS: In 2004, a total of 14,517 cases of TB were reported; 3,444 (24%) of these were among foreign-born persons who had entered the United States more than 5 yr previously. The rate of TB disease among foreign-born persons was 21.5/100,000, compared with 2.7/100,000 for U.S.-born persons, and varied by duration of residence and world region of origin. CONCLUSIONS: Almost one-quarter of all TB cases in the United States occur among foreign-born persons who have resided in the United States for longer than 5 yr; case rates for such persons from selected regions of origin remain substantially elevated. To eliminate TB, we must address the burden of LTBI in this high-risk group.

Communicable Disease Control↗
PubMed2005

Guidelines for preventing the transmission of Mycobacterium tuberculosis in health-care settings, 2005.

In 1994, CDC published the Guidelines for Preventing the Transmission of Mycobacterium tuberculosis in HealthCare Facilities, 1994. The guidelines were issued in response to 1) a resurgence of tuberculosis (TB) disease that occurred in the United States in the mid-1980s and early 1990s, 2) the documentation of several high-profile health-care--associated (previously termed "nosocomial") outbreaks related to an increase in the prevalence of TB disease and human immunodeficiency virus (HIV) coinfection, 3) lapses in infection control practices, 4) delays in the diagnosis and treatment of persons with infectious TB disease, and 5) the appearance and transmission of multidrug-resistant (MDR) TB strains. The 1994 guidelines, which followed statements issued in 1982 and 1990, presented recommendations for TB infection control based on a risk assessment process that classified health-care facilities according to categories of TB risk, with a corresponding series of administrative, environmental, and respiratory protection control measures. The TB infection control measures recommended by CDC in 1994 were implemented widely in health-care facilities in the United States. The result has been a decrease in the number of TB outbreaks in health-care settings reported to CDC and a reduction in health-care-associated transmission of Mycobacterium tuberculosis to patients and health-care workers (HCWs). Concurrent with this success, mobilization of the nation's TB control programs succeeded in reversing the upsurge in reported cases of TB disease, and case rates have declined in the subsequent 10 years. Findings indicate that although the 2004 TB rate was the lowest recorded in the United States since national reporting began in 1953, the declines in rates for 2003 (2.3%) and 2004 (3.2%) were the smallest since 1993. In addition, TB infection rates greater than the U.S. average continue to be reported in certain racial/ethnic populations. The threat of MDR TB is decreasing, and the transmission of M. tuberculosis in health-care settings continues to decrease because of implementation of infection-control measures and reductions in community rates of TB. Given the changes in epidemiology and a request by the Advisory Council for the Elimination of Tuberculosis (ACET) for review and update of the 1994 TB infection control document, CDC has reassessed the TB infection control guidelines for health-care settings. This report updates TB control recommendations reflecting shifts in the epidemiology of TB, advances in scientific understanding, and changes in health-care practice that have occurred in the United States during the preceding decade. In the context of diminished risk for health-care-associated transmission of M. tuberculosis, this document places emphasis on actions to maintain momentum and expertise needed to avert another TB resurgence and to eliminate the lingering threat to HCWs, which is mainly from patients or others with unsuspected and undiagnosed infectious TB disease. CDC prepared the current guidelines in consultation with experts in TB, infection control, environmental control, respiratory protection, and occupational health. The new guidelines have been expanded to address a broader concept; health-care--associated settings go beyond the previously defined facilities. The term "health-care setting" includes many types, such as inpatient settings, outpatient settings, TB clinics, settings in correctional facilities in which health care is delivered, settings in which home-based health-care and emergency medical services are provided, and laboratories handling clinical specimens that might contain M. tuberculosis. The term "setting" has been chosen over the term "facility," used in the previous guidelines, to broaden the potential places for which these guidelines apply.

Cross Infection↗
PubMed2005

Severe or fatal liver injury in 50 patients in the United States taking rifampin and pyrazinamide for latent tuberculosis infection.

BACKGROUND: Severe liver injuries were attributed to the rifampin and pyrazinamide (RZ) regimen after it was recommended for treating latent tuberculosis infection. Implicating RZ as the likeliest cause required excluding alternative causes. METHODS: US health departments reported data on patients who died or were hospitalized for liver disease within 1 month after taking RZ for latent tuberculosis infection from October 1998 through March 2004. The circumstances were investigated on site for each case. Illness characteristics, reasons for RZ treatment, doses and frequency of administration of pyrazinamide, monitoring during treatment, and causes of liver injury were determined. RESULTS: Liver injury was attributable to RZ use for all 50 patients reported, 12 of whom died. For 47 patients, RZ was the likeliest cause of liver injury. The median patient age was 44 years (range, 17-73 years). Thirty-two patients (64%) were male. Seven (16%) of 43 patients tested had hepatitis C virus antibodies, 1 (2%) of 45 had chronic hepatitis B, 3 (14%) of 22 had positive results of HIV serologic tests, 34 (71%) of 48 had alcohol use noted, and 33 (66%) of 50 were taking additional hepatotoxic medications. Six patients, 2 of whom died, had no predictors for liver disease. Patients who died were older (median age, 52 vs. 42 years; P=.08) and took a greater number of other medications (median number of medications, 4 vs. 2; P=.05) than did those who recovered, but these 2 factors were correlated (P<.01). Thirty-one patients (62%) were monitored according to guidelines, 9 of whom died. CONCLUSIONS: RZ was the likeliest cause of most of these liver injuries, some of which were fatal in spite of monitoring. Fatality was predicted by age or use of other medications, but none of the cofactors showed promise as a reliable clinical predictor of severe liver injury.

Adolescent↗
PubMed2005

Guidelines for using the QuantiFERON-TB Gold test for detecting Mycobacterium tuberculosis infection, United States.

On May 2, 2005, a new in vitro test, QuantiFERON-TB Gold (QFT-G, Cellestis Limited, Carnegie, Victoria, Australia), received final approval from the U.S. Food and Drug Administration as an aid for diagnosing Mycobacterium tuberculosis infection. This test detects the release of interferon-gamma (IFN-g) in fresh heparinized whole blood from sensitized persons when it is incubated with mixtures of synthetic peptides representing two proteins present in M. tuberculosis: early secretory antigenic target-6 (ESAT-6) and culture filtrate protein-10 (CFP-10). These antigens impart greater specificity than is possible with tests using purified protein derivative as the tuberculosis (TB) antigen. In direct comparisons, the sensitivity of QFT-G was statistically similar to that of the tuberculin skin test (TST) for detecting infection in persons with untreated culture-confirmed tuberculosis (TB). The performance of QFT-G in certain populations targeted by TB control programs in the United States for finding latent TB infection is under study. Its ability to predict who eventually will have TB disease has not been determined, and years of observational study of substantial populations would be needed to acquire this information. In July 2005, CDC convened a meeting of consultants and researchers with expertise in the field to review scientific evidence and clinical experience with QFT-G. On the basis of this review and discussion, CDC recommends that QFT-G may be used in all circumstances in which the TST is currently used, including contact investigations, evaluation of recent immigrants, and sequential-testing surveillance programs for infection control (e.g., those for health-care workers). This report provides specific cautions for interpreting negative QFT-G results in persons from selected populations. This report is aimed at public health officials, health-care providers, and laboratory workers with responsibility for TB control activities in the United States.

Antigens, Bacterial↗
PubMed2005

National survey to measure rates of liver injury, hospitalization, and death associated with rifampin and pyrazinamide for latent tuberculosis infection.

BACKGROUND: Cases of severe and fatal liver injury were reported after a 2-month course of rifampin-pyrazinamide therapy was recommended in 2000 as an alternative to isoniazid for treatment of latent tuberculosis infection. We estimated rates of rifampin-pyrazinamide-associated liver injury and compared these with historical rates for isoniazid. METHODS: We conducted a survey of state and city tuberculosis programs and other health care settings in the United States where rifampin-pyrazinamide was prescribed. The number of rifampin-pyrazinamide therapy initiations was collected, as well as the number of occurrences of (1) asymptomatic aspartate aminotransferase serum concentration >5 times the upper limit of normal, (2) symptomatic hepatitis (in which the patient was not hospitalized), (3) hospitalization for liver injury, (4) death with liver injury, and (5) treatment completion. We also searched a national pharmacy claims database (Verispan). Rates of these events were calculated. RESULTS: Among 139 programs, 110 (79%) responded; 87 (79%) had initiated rifampin-pyrazinamide therapy for a total of 8087 patients between January 2000 and June 2002. Rates per 1000 rifampin-pyrazinamide therapy initiations during this period were 25.6 (95% confidence interval [CI], 22.3-29.3) for asymptomatic aspartate aminotransferase level >5 times the upper limit of normal and 18.7 (95% CI, 15.9-21.9) for hepatitis. Seven fatalities and 23 hospitalizations occurred, with rates of 0.9 (95% CI, 0.4-1.9) and 2.8 (95% CI, 1.8-4.3) per 1000 rifampin-pyrazinamide therapy initiations, respectively. Of 8087 patients, 64% completed rifampin-pyrazinamide therapy. The Verispan search revealed 1 rifampin-pyrazinamide-associated hospitalization (2.9 hospitalizations per 1000 rifampin-pyrazinamide therapy initiations; 95% CI, 0.1-18.4) and no deaths. Articles on the use of isoniazid therapy for latent tuberculosis infection that were published after 1990 reported fatality rates of 0.0-0.3 deaths per 1000 persons. CONCLUSIONS: Rates of liver injury, hospitalization, and death associated with rifampin-pyrazinamide therapy exceed rates reported for isoniazid therapy. Because earlier randomized trials of rifampin-pyrazinamide lacked adequate statistical power to detect fatal events, the Centers for Disease Control and Prevention recommends that rifampin-pyrazinamide generally should not be used for treatment of latent tuberculosis infection.

Antitubercular Agents↗
PubMed2005

National plan for reliable tuberculosis laboratory services using a systems approach. Recommendations from CDC and the Association of Public Health Laboratories Task Force on Tuberculosis Laboratory Services.

Since the mid-1990s, public health laboratories have improved tuberculosis (TB) test performance, which has contributed to the resumption of the decline in TB incidence in the United States. However, to eliminate TB in the United States, further improvements are needed in laboratory services to support TB treatment, prevention, and control. A critical step is the development of an integrated system that ensures prompt and reliable laboratory testing and flow of information among laboratorians, clinicians, and TB-control officials. Challenges to developing such a system include 1) establishing lines of communication among laboratorians, clinicians, and TB-control officials; 2) expediting reporting of laboratory results, which can avoid delayed or inappropriate treatment and missed opportunities to prevent transmission; 3) developing evidence-based recommendations for use of new laboratory technologies; 4) maintaining staff proficiency in light of declining numbers of specimens to test, workforce shortages, and loss of laboratory expertise; and 5) upgrading laboratory information systems and connecting all partners. The report of the Association of Public Health Laboratories Task Force presents a framework to improve the future of TB laboratory services and describes the role of the laboratory in TB treatment and control, Task Force processes, general principles and benchmarks, and steps for the dissemination of the Task Force recommendations. This MMWR expands on the Task Force report by describing specific actions and performance measures to guide development and implementation of an integrated system for providing TB laboratory services. CDC and the Association of Public Health Laboratories have developed these guidelines so that laboratorians, clinicians, public health officials, administrators, and funding entities can work together to ensure that health-care providers and TB-control officials have the information needed to treat TB patients, prevent TB transmission, and ultimately eliminate TB in the United States.

Clinical Laboratory Information Systems↗
PubMed2005

Tuberculosis transmission in nontraditional settings: a decision-tree approach.

BACKGROUND: Tuberculosis (TB) transmission in nontraditional settings and relationships (non-TSR) often eludes detection by conventional contact investigation and is increasingly common. The U.S.-based National Tuberculosis Genotyping and Surveillance Network collected epidemiologic data and genotyping results of Mycobacterium tuberculosis isolates from 1996 to 2000. METHODS: In 2003-2004, we determined the number and characteristics of TB patients in non-TSR that were involved in recent transmission, generated a decision tree to profile those patients, and performed a case-control study to identify predictors of being in non-TSR. RESULTS: Of 10,844 culture-positive reported TB cases that were genotyped, 4724 (43.6%) M. tuberculosis isolates were clustered with at least one other isolate. Among these, 520 (11%) had epidemiologic linkages discovered during conventional contact investigation or cluster investigation and confirmed by genotyping results. The decision tree identified race/ethnicity (non-Hispanic white or black) as having the greatest predictive ability to determine patients in non-TSR, followed by being aged 15 to 24 years and having positive or unknown HIV infection status. From the 520, 85 (16.4%) had non-TSR, and 435 (83.6%) had traditional settings and relationships (TSR). In multivariate analyses, patients in non-TSR were significantly more likely than those in TSR to be non-Hispanic white (adjusted odds ratio [aOR]=6.1; 95% confidence interval [CI]=1.7-21.1]) or to have an M. tuberculosis isolate resistant to rifampin (aOR=5.2; 95% CI=1.5-17.7). CONCLUSIONS: Decision-tree analyses can be used to enhance both the efficiency and effectiveness of TB prevention and control activities in identifying patients in non-TSR.

Adolescent↗
PubMed2004

Tuberculosis serodiagnosis in a predominantly HIV-infected population of hospitalized patients with cough, Botswana, 2002.

A sensitive and accurate tuberculosis (TB) serodiagnostic test would aid in the control of TB, but results of current tests are relatively unreliable for persons infected with human immunodeficiency virus (HIV). We evaluated a new prototype immunochromatographic strip test and 5 commercially available serodiagnostic TB tests in a prospective study comprised of 465 consecutively enrolled patients with suspected TB from 2 hospitals in Botswana. Consenting adults underwent HIV testing, >/=2 sputum smears and cultures, and mycobacterial blood culture. Patients were defined as having TB on the basis of any positive smear or culture. Between January and September 2002, 465 of 498 consecutive patients consented to enrollment. A total of 384 patients (83%) were infected with HIV, and 175 (38%) had TB; the mycobacterial blood culture was the sole source of diagnosis for 26 patients (15%) with TB. Among the tests evaluated, the sensitivity was 0%-63%, the specificity was 39%-99%, the positive predictive value was 0%-39%, and the negative predictive value was 63%-65%. We conclude that the serodiagnostic tests evaluated in this study lacked sufficient sensitivity as sole tests for TB in this population.

AIDS-Related Opportunistic Infections↗
PubMed2003

Epidemiology of tuberculosis.

In the United States, many people erroneously think that tuberculosis (TB) is a disease of the past--an illness that no longer constitutes a public health threat. In reality, TB is one of the leading global causes of morbidity and mortality. According to the World Health Organization, which compiles annual country profiles of reported TB cases using standardized case definitions, 2.4 million cases were reported in 2001. However, because of underreporting, the number of new TB cases is estimated to be 8.3 million, including 1.8 million deaths. In the United States, after more than 3 decades of steady downward trends, an unprecedented resurgence of TB occurred between 1985 and 1992. This increase was associated with deficient infrastructure, the human immunodeficiency virus (HIV) epidemic, immigration, outbreaks in congregate settings, and widespread occurrence of multidrug resistant TB strains. The resultant increased concerns provided the impetus for the development of a national action plan to combat MDR and the mobilization of new resources. Consequently, the incidence of TB cases has decreased from 1992 through 2002. New challenges are evident and must be addressed to achieve the agreed-on goal of eliminating TB in the United States. This report describes the global epidemiology of TB and the epidemiology in the United States, and outlines future challenges to the elimination of TB in the United States.

Adult↗
PubMed2002

Childhood vaccinations and risk of asthma.

BACKGROUND: A few previous studies have suggested that childhood vaccines, particularly whole cell pertussis vaccine, may increase the risk of asthma. We evaluated the suggested association between childhood vaccinations and risk of asthma. METHODS: Cohort study involving 167,240 children who were enrolled in 4 large health maintenance organizations during 1991 to 1997, with follow-up from birth until at least 18 months to a maximum of 6 years of age. Vaccinations were ascertained through computerized immunization tracking systems, and onset of asthma was identified through computerized data on medical care encounters and medication dispensings. RESULTS: In the study 18,407 children (11.0%) developed asthma, with a median age at onset of 11 months. The relative risks (95% confidence intervals) of asthma were: 0.92 (0.83 to 1.02) for diphtheria, tetanus and whole cell pertussis vaccine; 1.09 (0.9 to 1.23) for oral polio vaccine; 0.97 (0.91 to 1.04) for measles, mumps and rubella (MMR) vaccine; 1.18 (1.02 to 1.36) for Haemophilus influenzae type b (Hib); and 1.20 (1.13 to 1.27) for hepatitis B vaccine. The Hib result was not consistent across health maintenance organizations. In a subanalysis restricted to children who had at least 2 medical care encounters during their first year, the relative risks decreased to 1.07 (0.71 to 1.60) for Hib and 1.09 (0.88 to 1.34) for hepatitis B vaccine. CONCLUSION: There is no association between diphtheria, tetanus and whole cell pertussis vaccine, oral polio vaccine or measles, mumps and rubella vaccine and the risk of asthma. The weak associations for Hib and hepatitis B vaccines seem to be at least partially accounted for by health care utilization or information bias.

Asthma↗