Ida M. Onorato

An outbreak of community-acquired Pneumocystis carinii pneumonia. Initial manifestation of cellular immune dysfunction.

Eleven cases of community-acquired Pneumocystis carinii pneumonia occurred between 1979 and 1981 and prompted clinical and immunologic evaluation of the patients. Young men who were drug abusers (seven patients), homosexuals (six), or both (two) presented with pneumonia. Immunologic testing revealed that absolute lymphocyte counts, T-cell counts, and lymphocyte proliferation were depressed, and that humoral immunity was intact. Of the 11 patients, one was found to have Kaposis sarcoma, and another had angioimmunoblastic lymphadenopathy. Eight patients died. In the remaining three, no diagnosis of an immunosuppressive disease was established, despite persistence of immune defects. These cases of pneumocystosis suggest the importance of cell-mediated immune function in the defense against P. carinii. The occurrence of this infection among drug abusers and homosexuals indicates that these groups may be at high risk for this infection.

The epidemiology of tuberculosis among foreign-born persons in the United States, 1986 to 1993

BACKGROUND One third of the worlds population is infected with Mycobacterium tuberculosis, and in the developed countries immigration is a major force that sustains the incidence of tuberculosis. We studied the effects of immigration on the epidemiology of tuberculosis and its recent resurgence in the United States. METHODS We analyzed data from the national tuberculosis reporting system of the Centers for Disease Control and Prevention. Since 1986 reports of tuberculosis have included the patients country of origin. Population estimates for foreign-born persons were derived from special samples from the 1980 and 1990 censuses. RESULTS The proportion of persons reported to have tuberculosis who were foreign-born increased from 21.6 percent (4925 cases) in 1986 to 29.6 percent (7346 cases) in 1993. For the entire eight-year period, most foreign-born patients with tuberculosis were from Latin America (43.9 percent; 21,115 cases) and Southeast Asia (34.6 percent; 16,643 cases). Among foreign-born persons the incidence rate was almost quadruple the rate for native residents of the United States (30.6 vs. 8.1 per 100,000 person-years), and 55 percent of immigrants with tuberculosis had the condition diagnosed in their first five years in the United States. CONCLUSIONS Immigration has had an increasingly important effect on the epidemiology of tuberculosis in the United States. It will be difficult to eliminate tuberculosis without better efforts to prevent and control it among immigrants and greater efforts to control it in the countries from which they come.

Transmission of Multidrug-Resistant Mycobacterium tuberculosis during a Long Airplane Flight

BACKGROUND In April 1994, a passenger with infectious multi-drug resistant tuberculosis traveled on commercial-airline flights from Honolulu to Chicago and from Chicago to Baltimore and returned one month later. We sought to determine whether she had infected any of her contacts on this extensive trip. METHODS Passengers and crew were identified from airline records and were notified of their exposure, asked to complete a questionnaire, and screened by tuberculin skin tests. RESULTS Of the 925 people on the airplanes, 802 (86.7 percent) responded. All 11 contacts with positive tuberculin skin tests who were on the April flights and 2 of 3 contacts with positive tests who were on the Baltimore-to-Chicago flight in May had other risk factors for tuberculosis. More contacts on the final, 8.75-hour flight from Chicago to Honolulu had positive skin tests than those on the other three flights (6 percent, as compared with 2.3, 3.8, and 2.8 percent). Of 15 contacts with positive tests on the May flight from Chicago to Honolulu, 6 (4 with skin-test conversion) had no other risk factors; all 6 had sat in the same section of the plane as the index patient (P=0.001). Passengers seated within two rows of the index patient were more likely to have positive tuberculin skin tests than those in the rest of the section (4 of 13, or 30.8 percent, vs. 2 of 55, or 3.6 percent; rate ratio, 8.5; 95 percent confidence interval, 1.7 to 41.3; P=0.01). CONCLUSIONS The transmission of Mycobacterium tuberculosis that we describe aboard a commercial aircraft involved a highly infectious passenger, a long flight, and close proximity of contacts to the index patient.

Behavioral Surveillance Among People at Risk for HIV Infection in the U.S.: The National HIV Behavioral Surveillance System

The Centers for Disease Control and Prevention, in collaboration with 25 state and local health departments, began the National HIV Behavioral Surveillance System (NHBS) in 2003. The system focuses on people at risk for HIV infection and surveys the three populations at highest risk for HIV in the United States: men who have sex with men, injecting drug users, and high-risk heterosexuals. The project collects information from these three populations during rotating 12-month cycles. Methods for recruiting participants vary for each at-risk population, but NHBS uses a standardized protocol and core questionnaire for each cycle. Participating health departments tailor their questionnaire to collect information about specific prevention programs offered in their geographic area and to address local data needs. Data collected from NHBS will be used to describe trends in key behavioral risk indicators and evaluate current HIV prevention programs. This information in turn can be used to identify gaps in prevention services and target new prevention activities with the goal of reducing new HIV infections in the United States.

Interpretation of Restriction Fragment Length Polymorphism Analysis of Mycobacterium tuberculosis Isolates from a State with a Large Rural Population

Epidemiologic relatedness of Mycobacterium tuberculosis isolates from Arkansas residents diagnosed with tuberculosis in 1992-1993 was assessed using IS6110- and pTBN12-based restriction fragment length polymorphism (RFLP) and epidemiologic investigation. Patients with isolates having similar IS6110 patterns had medical records reviewed and were interviewed to identify epidemiologic links. Complete RFLP analyses were obtained for isolates of 235 patients; 78 (33%) matched the pattern of > or = 1 other isolate, forming 24 clusters. Epidemiologic connections were found for 33 (42%) of 78 patients in 11 clusters. Transmission of M. tuberculosis likely occurred many years in the past for 5 patients in 2 clusters. Of clusters based only on IS6110 analyses, those with > or = 6 IS6110 copies had both a significantly greater proportion of isolates that matched by pTBN12 analysis and patients with epidemiologic connections, indicating IS6110 patterns with few bands lack strain specificity. Secondary RFLP analysis increased specificity, but most clustered patients still did not appear to be epidemiologically related. RFLP clustering in rural areas may not represent recent transmission.

Extensive Transmission of Mycobacterium tuberculosis from a Child

BACKGROUND AND METHODS Young children rarely transmit tuberculosis. In July 1998, infectious tuberculosis was identified in a nine-year-old boy in North Dakota who was screened because extrapulmonary tuberculosis had been diagnosed in his female guardian. The child, who had come from the Republic of the Marshall Islands in 1996, had bilateral cavitary tuberculosis. Because he was the only known possible source for his female guardians tuberculosis, an investigation of the childs contacts was undertaken. We identified family, school, day-care, and other social contacts and notified these people of their exposure. We asked the contacts to complete a questionnaire and performed tuberculin skin tests. RESULTS Of the 276 contacts of the child whom we tested, 56 (20 percent) had a positive tuberculin skin test (induration of at least 10 mm), including 3 of the childs 4 household members, 16 of his 24 classroom contacts, 10 of 32 school-bus riders, and 9 of 61 day-care contacts. A total of 118 persons received preventive therapy, including 56 young children who were prescribed preventive therapy until skin tests performed at least 12 weeks after exposure were negative. The one additional case identified was in the twin brother of the nine-year-old patient. The twin was not considered infectious on the basis of a sputum smear that was negative on microscopical examination. CONCLUSIONS This investigation showed that a young child can transmit Mycobacterium tuberculosis to a large number of contacts. Children with tuberculosis, especially cavitary or laryngeal tuberculosis, should be considered potentially infectious, and screening of their contacts for infection with M. tuberculosis or active tuberculosis may be required.

Seroprevalence of HTLV-I and HTLV-II among Intravenous Drug Users and Persons in Clinics for Sexually Transmitted Diseases

Abstract Background. The human T-cell lymphotropic virus Type I (HTLV-I) is associated with adult T-cell leukemia and myelopathy, whereas HTLV-II infection has uncertain clinical consequences. We assessed the seroprevalence of these retroviruses among intravenous drug users and among patients seen at clinics for sexually transmitted diseases (STD clinics). Methods. We used serum samples that were collected in eight cities in 1988 and 1989 during surveys of human immunodeficiency virus infection among intravenous drug users entering treatment and persons seen in STD clinics. The serum samples were tested for antibodies to HTLV, and positive specimens were tested further by a synthetic peptide-based enzyme-linked immunosorbent assay to differentiate between HTLV-I and HTLV-II. Results. Among 3217 intravenous drug users in 29 drug-treatment centers, the median seroprevalence rates of HTLV varied widely according to city (range, 0.4 percent in Atlanta to 17.6 percent in Los Angeles). Seroprevalence increased ...

HIV INFECTION AMONG HOMELESS ADULTS AND RUNAWAY YOUTH, UNITED STATES, 1989-1992

ObjectivesHomeless persons have an increased risk of HIV infection because of a high prevalence of HlV-related risk behaviors. These include drug use, sexual contact with persons at risk for HIV infection, and the exchange of sex for drugs. The objectives of this investigation were to describe HIV seroprevalence rates in homeless adults and runaway youth. MethodsIn 1989, the Centers for Disease Control and Prevention began collaboration with state and local health departments to conduct HIV seroprevalence surveys in homeless populations. Unlinked HIV seroprevalence surveys were conducted in 16 sites; 11 provided medical services primarily to homeless adults, and five to runaway youth aged <25 years. ResultsFrom January 1989 through December 1992, annual surveys were conducted in 16 sites in 14 cities. Site-specific seroprevalence rates ranged from 0–21.1% (median, 3.3%). Among homeless adults in three sites, rates were higher among men who had sex with other men and those who injected drugs than among persons with other risk exposures (28.9 versus 5.3%). In general, rates were higher for heterosexual men than for women and higher among African Americans than whites. In sites providing services to homeless youth, HIV seroprevalence rates ranged from 0–7.3% (median, 2.3%). ConclusionsThese data indicate that HIV infection among homeless adults and runaway youth is an important public health problem. HIV prevention and treatment should be integrated into comprehensive health and medical programs serving homeless populations.

Spread of strain W, a highly drug-resistant strain of Mycobacterium tuberculosis, across the United States.

Strain W, a highly drug-resistant strain of Mycobacterium tuberculosis, was responsible for large nosocomial outbreaks in New York in the early 1990s. To describe the spread of strain W outside New York, we reviewed data from epidemiologic investigations, national tuberculosis surveillance, regional DNA fingerprint laboratories, and the Centers for Disease Control and Prevention Mycobacteriology Laboratory to identify potential cases of tuberculosis due to strain W. From January 1992 through February 1997, 23 cases were diagnosed in nine states and Puerto Rico; 8 were exposed to strain W in New York before their diagnosis; 4 of the 23 transmitted disease to 10 others. Eighty-six contacts of the 23 cases are presumed to be infected with strain W; 11 completed alternative preventive therapy. Strain W tuberculosis cases will occur throughout the United States as persons infected in New York move elsewhere. To help track and contain this strain, health departments should notify the Centers for Disease Control and Prevention of cases of tuberculosis resistant to isoniazid, rifampin, streptomycin, and kanamycin.

Simultaneous Infection with Multiple Strains of Mycobacterium tuberculosis

Drug-susceptible and drug-resistant isolates of Mycobacterium tuberculosis were recovered from 2 patients, 1 with isoniazid-resistant tuberculosis (patient 1) and another with multidrug-resistant tuberculosis (patient 2). An investigation included patient interviews, record reviews, and genotyping of isolates. Both patients worked in a medical-waste processing plant. Transmission from waste was responsible for at least the multidrug-resistant infection. We found no evidence that specimens were switched or that cross-contamination of cultures occurred. For patient 1, susceptible and isoniazid-resistant isolates, collected 15 days apart, had 21 and 19 restriction fragments containing IS6110, 18 of which were common to both. For patient 2, a single isolate contained both drug-susceptible and multidrug-resistant colonies, demonstrating 10 and 11 different restriction fragments, respectively. These observations indicate that simultaneous infections with multiple strains of M. tuberculosis occur in immunocompetent hosts and may be responsible for conflicting drug-susceptibility results, though the circumstances of infections in these cases may have been unusual.