Randomized trial of supplementary interviewing techniques to enhance recall of sexual partners in contact interviews.

BACKGROUND: People with multiple sex partners tend to forget a significant proportion when recalling them. METHODS: Randomized trial of supplementary interviewing techniques during routine partner notification contact interviews for chlamydia, gonorrhea, and syphilis in Colorado Springs, CO. Cases with multiple sex partners in the last 3 months (n = 123) participated. Interviewers prompted nonspecifically and read back the list of elicited partners after cases recalled partners on their own. We then randomly assigned cases to receive 1 of 3 sets of recall cues: (1) an experimental set of cues consisting of locations where people meet partners, role relationships, network ties, and first letters of names; (2) another experimental set including common first names; and (3) control cues referring to individual characteristics (e.g., physical appearance). RESULTS: Nonspecific prompting and reading back the list each increased the number of additional partners elicited and located by 3% to 5% on average. On average, the combined location/role/letter/network cues elicited more additional partners (0.57) than did the first-name (0.29) and individual characteristics (0.28) cues. The location and first-name cues were the most effective in eliciting located partners. The supplementary techniques increased the number of new cases found by 12% and, importantly, identified branches of the sexual network that would not otherwise have been discovered. CONCLUSION: Elicitation of sex partners can be enhanced in contact interviews with simple interviewing techniques, resulting in improved network ascertainment and sexually transmitted disease case finding.

Genetic diversity of human pathogenic members of the Fusarium oxysporum complex inferred from multilocus DNA sequence data and amplified fragment length polymorphism analyses: evidence for the recent dispersion of a geographically widespread clonal lineage and nosocomial origin.

Fusarium oxysporum is a phylogenetically diverse monophyletic complex of filamentous ascomycetous fungi that are responsible for localized and disseminated life-threatening opportunistic infections in immunocompetent and severely neutropenic patients, respectively. Although members of this complex were isolated from patients during a pseudoepidemic in San Antonio, Tex., and from patients and the water system in a Houston, Tex., hospital during the 1990s, little is known about their genetic relatedness and population structure. This study was conducted to investigate the global genetic diversity and population biology of a comprehensive set of clinically important members of the F. oxysporum complex, focusing on the 33 isolates from patients at the San Antonio hospital and on strains isolated in the United States from the water systems of geographically distant hospitals in Texas, Maryland, and Washington, which were suspected as reservoirs of nosocomial fusariosis. In all, 18 environmental isolates and 88 isolates from patients spanning four continents were genotyped. The major finding of this study, based on concordant results from phylogenetic analyses of multilocus DNA sequence data and amplified fragment length polymorphisms, is that a recently dispersed, geographically widespread clonal lineage is responsible for over 70% of all clinical isolates investigated, including all of those associated with the pseudoepidemic in San Antonio. Moreover, strains of the clonal lineage recovered from patients were conclusively shown to genetically match those isolated from the hospital water systems of three U.S. hospitals, providing support for the hypothesis that hospitals may serve as a reservoir for nosocomial fusarial infections.