The collectivity of sexual behaviour.

Human behaviour can be viewed as a collective phenomenon, determined partly by the group to which individuals belong. Collectivities of health behaviour have been found in alcohol consumption, hypertension, obesity, mental illness, and sodium intake in that the average level of risk is associated with the percentage of individuals at extremely high risk.The goal was to investigate whether sexual behaviour may be collectively determined. A cross-sectional US survey was conducted. Across 45 states, the mean number of lifetime sex partners excluding persons with >10, >20, and >40 lifetime partners was strongly associated with the proportion with >10, > 20 and > 40 lifetime sex partners, respectively, among men and women. Sexual activity may represent collectively determined behaviour. If so, interventions to reduce high-risk sexual behaviour to prevent HIV or sexually transmitted diseases (STDs) may be more effective if they address the entire population, rather than target only those at the extremes of risk.

Relationship between home food-handling practices and sporadic salmonellosis in adults in Louisiana, United States.

Salmonellosis is the leading cause of death caused by foodborne bacterial pathogens in the United States. Approximately 90% of salmonella infections are sporadic, but most of what is known about salmonellosis has come from outbreak investigations. We studied the risk for sporadic salmonellosis among 115 persons aged > or = 15 years reported to the Louisiana Office of Public Health during May 1998-April 1999, compared with 115 age-matched controls. Significantly more case-patients than controls had chronic underlying medical conditions [adjusted odds ratio (aOR) = 4.3; 95% confidence interval (CI) = 2.2-8.7]. Although reported consumption of specific food items likely to contain salmonella was not associated with illness, inconsistent handwashing between preparation of meat and non-meat items was associated with illness (aOR = 8.3; CI = 1.1-61.8). Enhanced measures to provide a consistently safe food supply and promote safer food preparation in households will depend on prevention of sporadic salmonellosis.

Characteristics of persons with syphilis in areas of persisting syphilis in the United States: sustained transmission associated with concurrent partnerships.

BACKGROUND AND GOAL: In areas with persistent syphilis, to characterize persons at higher risk for transmitting syphilis. STUDY DESIGN: Cohort study. Structured interviews of persons with early syphilis from four research centers were linked to outcomes of partner tracing. RESULTS: Of 743 persons with syphilis, 229 (31%) reported two or more partners in the previous month, and 57 (8%) received money or drugs for sex in the previous three months. Persons with at least one partner at an earlier stage of syphilis than themselves were defined as transmitters; 63 (8.5%) of persons with early syphilis met this definition. Having concurrent partners (two or more in one week in the last month) was independently associated with being a transmitter. CONCLUSION: Sexual network/behavioral characteristics of syphilis patients and their partners, such as concurrency, can help identify persons at higher risk for transmitting syphilis who should receive emphasis in disease prevention activities.

Determinants of persistent and recurrent Chlamydia trachomatis infection in young women: results of a multicenter cohort study.

BACKGROUND: Sequelae of genital Chlamydia trachomatis infection in women are more strongly linked to repeat infections than to initial ones, and persistent or subsequent infections foster continued transmission. OBJECTIVE: To identify factors associated with persistent and recurrent chlamydial infection in young women that might influence prevention strategies. METHODS: Teenage and young adult women with uncomplicated C trachomatis infection attending reproductive health, sexually transmitted disease, and adolescent medicine clinics in five US cities were recruited to a cohort study. Persistent or recurrent chlamydial infection was detected by ligase chain reaction (LCR) testing of urine 1 month and 4 months after treatment. RESULTS: Among 1,194 women treated for chlamydial infection, 792 (66.4%) returned for the first follow-up visit, 50 (6.3 %) of whom had positive LCR results. At that visit, women who resumed sex since treatment were more likely to have chlamydial infection (relative risk [RR], 2.0; 95% CI, 1.03-3.9), as were those who did not complete treatment (RR, 3.4; 95% CI, 1.6-7.3). Among women who tested negative for C trachomatis at the first follow-up visit, 36 (7.1%) of 505 had positive results by LCR at the second follow-up visit. Reinfection at this visit was not clearly associated with having a new sex partner or other sexual behavior risks; new infection was likely due to resumption of sex with untreated partners. Overall, 13.4% of women had persistent infection or became reinfected after a median of 4.3 months, a rate of 33 infections per 1,000 person months. CONCLUSIONS: Persistent or recurrent infection is very common in young women with chlamydial infection. Improved strategies are needed to assure treatment of women's male sex partners. Rescreening, or retesting of women for chlamydial infection a few months after treatment, also is recommended as a routine chlamydia prevention strategy.

Strategies for syphilis prevention: findings from surveys in a high-incidence area.

BACKGROUND: The persistence of syphilis in the United States suggests that a better understanding is needed of the potential for various public health approaches to prevent the spread of the disease. STUDY DESIGN: The authors conducted surveys of 92 persons with early syphilis, 56 uninfected sexual contacts, and 143 neighborhood controls in the Baton Rouge, Louisiana area. The surveys collected information regarding sexual behavior, access to and use of healthcare services, encounters at sites at which serologic screening for syphilis could be done, and exposure to interventions designed to prevent HIV infection. RESULTS: All groups reported high-risk sexual behavior. Cases and contacts were more likely than controls to report two or more sex partners in the previous year, but the three groups were similar in the percentage reporting five or more sex partners. Cases had poor access to health care and by some measures this access was less than that of controls. The potential screening site visited most frequently by cases was the public hospital emergency room (40%). Cases were less likely to have been exposed to programs designed to prevent HIV infection than uninfected contacts and controls combined (odds ratios, 0.51-0.66). CONCLUSIONS: Persons with syphilis were not unlike others in their neighborhoods, suggesting that syphilis is a sentinel event that indicates an entire neighborhood is at risk. Improvements in access to health care for sexually transmitted disease-related symptoms, screening in sites such as public hospital emergency rooms, and emphasizing sexual risk-reduction interventions may limit the spread of syphilis in these neighborhoods. To prevent syphilis in the long term, public health programs should also try to better understand and change other community-level socioeconomic factors that influence sexual behavior.

Multi-state outbreaks of acute gastroenteritis traced to fecal-contaminated oysters harvested in Louisiana.

Norwalk-like viruses (NLVs), or small round structured viruses, are known to cause acute gastroenteritis associated with eating contaminated shellfish. Between 1993 and 1996, three oyster-related gastroenteritis outbreaks attributed to NLV occurred in Louisiana. Intensive trace-back and environmental investigations revealed that the overboard disposal of sewage by oyster harvesters into oyster-bed waters was the most likely source of contamination in at least two of the outbreaks. The small infectious dose of NLV, the large quantity of virus particles in stool, and the ability of oysters to concentrate virus particles suggest that oyster-related outbreaks will continue unless strong control measures are established. Efforts to halt improper sewage disposal in oyster-harvesting waters, including overboard sewage discharge, must be undertaken if future outbreaks are to be prevented.

Potential for community-based screening, treatment, and antibiotic prophylaxis for syphilis prevention.

BACKGROUND: The recent syphilis epidemic in Louisiana occurred predominantly among disadvantaged African Americans who may distrust public health agencies and prevention efforts. OBJECTIVES: To determine community perceptions regarding trust and use of public health clinics, to assess whether race of provider is important to persons at risk for syphilis, and to assess the willingness of persons to participate in syphilis screening, treatment, and antibiotic prophylaxis. STUDY DESIGN: Qualitative interviews were conducted with 18 community leaders and 38 community members who were at risk for syphilis. Quantitative surveys were completed by persons with primary or secondary syphilis (n = 92), their sexual contacts (n = 56), and with neighborhood controls (n = 143). Three possible programs for syphilis screening and antibiotic prophylaxis were proposed (1) bar setting; (2) home setting, and (3) mobile health-van setting in high-risk communities. RESULTS: In qualitative interviews, community leaders and community members reported a high degree of trust in the public sexually transmitted disease clinic. A majority of respondents felt that race was not a factor in choosing healthcare providers. Respondents favored the provision of services in a mobile health van over in a bar or in their homes. In quantitative interviews, more than 80% of community members surveyed reported that they would go to a mobile health van for syphilis testing. Nearly two thirds of respondents reported that they would be willing to take oral prophylaxis for syphilis, and more than half of respondents reported that they would accept an injection. CONCLUSIONS: Community members trust the public sexually transmitted disease (STD) clinic, are generally not concerned with the race of healthcare providers, and are supportive of community-based STD screening, treatment, and antibiotic prophylaxis provided from a mobile clinic.

The effect of modest monetary incentives on follow-up rates in sexually transmitted disease studies.

The purpose of the study was to determine if follow-up rates in sexually transmitted disease (STD) research could be improved by offering modest monetary incentives. Women aged 14-34, infected with Chlamydia trachomatis, and enrolled in either of 2 studies between May 1995 and January 1999 were included. Beginning in March 1996 participants were offered a $20 incentive to return to both the one- and four-month follow-up visits. Data were analysed using polychotomous logistic regression. Of 962 women followed, the majority (74.7%) received monetary incentives and 66% returned for at least one visit. Women who received the incentive were more likely (OR 1.9, CI 1.2-2.9) to return for either one or both of their follow-up visits after adjusting for interviewer and the months of work experience of that interviewer. Age and method of birth control were not associated with return rates. The study provides evidence that modest monetary incentives can improve follow-up rates.

A structural model of health behavior: a pragmatic approach to explain and influence health behaviors at the population level.

BACKGROUND: Behavior is influenced by individual-level attributes as well as by the conditions under which people live. Altering policies, practices, and the conditions of life can directly and indirectly influence individual behavior. This paper builds on existing ecological theories of health behavior by specifying structural mechanisms by which population-level factors effect change in individual health behaviors. METHODS: This paper moves ecological theory from model building to a pragmatic characterization of structural interventions. We examined social and environmental factors beyond individual control and mechanisms as to how they influence behavior. RESULTS: Four categories of structural factors are identified: (1) availability of protective or harmful consumer products, (2) physical structures (or physical characteristics of products), (3) social structures and policies, and (4) media and cultural messages. The first three can directly influence individuals through facilitating or constraining behavior. The fourth, media, operates by changing individual-level attitudes, beliefs, and cognitions, as well as group norms. CONCLUSION: Interventions that target the four identified structural factors are a means to provide conditions that not only reduce high-risk behavior but also prevent the adoption of high-risk behaviors. Structural interventions are important and underutilized approaches for improving our nation's health.

Initially unrecognized distribution of a commercially cooked meat product contaminated over several months with Salmonella serotype Infantis.

An outbreak of salmonellosis occurred among 63 wedding participants. The outbreak was investigated through cohort, laboratory, and environmental studies. Consumption of rice-dressing made from a commercially cooked, meat-based, rice-dressing mix was strongly associated with illness. Nineteen patient isolates, six company/grocery store isolates cultured from the rice-dressing mix, and one environmental isolate from a pump in the production line were of an identical outbreak strain of Salmonella Infantis characterized by pulsed-field gel electrophoresis. In the production line, cooked rice-dressing mix tested negative for S. Infantis before and positive after contact with the contaminated pump. The dressing-mix had an estimated 200 colony-forming units of salmonella per gram of product, and > 180,000 pounds were distributed in 9 states for > or = 2 months before contamination was recognized. Food manufacturers should be required to use systematic, hazard analysis critical control point risk management practices for all processed meat products, validated by periodic microbiologic monitoring of the end product.

Repeated school-based screening for sexually transmitted diseases: a feasible strategy for reaching adolescents.

OBJECTIVES: To determine whether repeated school-based screening and treatment for chlamydia and gonorrhea will decrease the prevalence of infection among students. DESIGN: At three high schools serving over 2000 students, all 9th through 12th grade students were given the opportunity to be tested during three consecutive school years for chlamydia and gonorrhea, using urine ligase chain reaction tests. Five comparable schools with 5063 students enrolled served as wait-listed controls. SETTING: Eight urban public high schools in Louisiana. PARTICIPANTS: Annually, 52% to 65% of all enrolled students participated; among those enrolled in schools for > or = 2 years, 83.4% of students were tested at least once. INTERVENTION: Education of all students; counseling and treatment of infected students with oral single-dose antibiotic therapy. MAIN OUTCOME MEASURE: Prevalence of Chlamydia trachomatis and gonorrhea infection. RESULTS: At first test, 286 (11.5%) of 2497 girls and 143 (6.2%) of 2308 boys were infected with chlamydia, and 48 (2.5%) of 1883 girls and 19 (1.2%) of 1628 boys had gonorrhea. Over 90% of infections were asymptomatic. With repeated testing, chlamydia prevalence among boys dropped to half the rate of comparison schools (3.2% vs 6.4%). Among girls chlamydia prevalence declined only slightly (10.3% vs 11. 9% in comparison schools). CONCLUSION: There are high rates of asymptomatic sexually transmitted diseases (STDs) in the general urban school population. Repeated screening and treatment are associated with declines in chlamydia prevalence among boys. Expansion of STD screening and treatment programs to school settings is likely to be a critical component of a national strategy to control bacterial STDs.

Gonorrhea incidence and HIV testing and counseling among adolescents and young adults seen at a clinic for sexually transmitted diseases.

OBJECTIVE: To determine whether HIV testing and posttest counseling may be associated with an increase in gonorrhea incidence among adolescents and young adults seen at a clinic for sexually transmitted diseases (STD). DESIGN: A historical cohort study with the collection of longitudinal data on the patients' HIV testing and counseling experience. SETTING: Delgado STD clinic of New Orleans, Louisiana, a public ambulatory primary care center that serves mainly the economically disadvantaged Black population. PATIENTS: A record-based inception cohort of 4031 patients aged 15-25 years diagnosed at the clinic between June 1989 and May 1991 with a first lifetime gonorrhea infection. INTERVENTION: Routine confidential HIV tests and posttest counseling sessions experienced at the clinic during follow-up. OUTCOME MEASURE: Incidence rate of reported gonorrhea reinfection. RESULTS: Of the patients, 51.5% were tested once for HIV antibodies and 25.9% twice or more. Formal posttest counseling occurred after 8.5% of the 4665 HIV-negative and 44.0% of the 49 HIV-positive tests. In the most pessimistic of several models controlling for history of gonorrhea, HIV testing and counseling history, and other potential confounding factors, a significantly lower rate of gonorrhea reinfection was observed after a first HIV-negative test than before [adjusted relative risk (RR), 0.66; 95% confidence interval (CI), 0.59-0.74; P < 0.00011. As compared with the pretest period, significantly higher rates of gonorrhea were observed after respectively a second (RR, 1.18; 95% CI, 1.01-1.37; P = 0.03) and a third (RR, 1.52; 95% CI, 1.22-1.88; P = 0.0001) HIV-negative test. No significant association was found between HIV-positive testing and any variation in gonorrhea rate (RR, 0.95; 95% CI, 0.56-1.62; P = 0.85). Posttest counseling for HIV-negative and HIV-positive results were followed respectively by a significantly higher rate of gonorrhea (RR; 1.27; 95% CI, 1.09-1.48; P = 0.002) and a non-significantly lower rate of gonorrhea (RR, 0.53; 95% CI, 0.17-1.60; P = 0.85). CONCLUSION: Our results do not exclude the possibility of a modest increase in gonorrhea incidence after routine HIV testing and counseling in an STD clinic. Nevertheless, this conclusion holds only under the least favorable assumptions and applies solely to a minority of patients.

Usefulness of partner notification for syphilis control.

BACKGROUND AND OBJECTIVES: In the United States, the recent syphilis epidemic has been followed by the lowest rates in 40 years. Syphilis control in the United States traditionally emphasizes partner notification; however, its role in elimination efforts remains undefined. GOAL OF THE STUDY: To describe and compare outcome measures of partner notification during and after the epidemic. STUDY DESIGN: Descriptive analysis of data obtained from interview records of patients with early syphilis in Louisiana during 1993 through 1996. RESULTS: Of 12,927 patients with early syphilis, 3,245 (25%) were identified through partner notification. A total of 7,120 (55%) patients named at least one infected contact. Patients named a mean of 2.3 contacts, resulting in 29,248 named contacts; of these, 22,825 (78%) were examined. A total of 9,374 (41%) of examined contacts were infected, including 18% who were newly identified as infected. No substantial differences were found between epidemic and postepidemic years. CONCLUSION: Partner notification is successful in identifying and treating a large number of infected persons. However, complementary strategies will be needed to eliminate syphilis.

Cost as a barrier to condom use: the evidence for condom subsidies in the United States.

OBJECTIVES: This study sought to determine the impact of price on condom use. METHODS: A program based on distribution of condoms at no charge was replaced with one providing low-cost condoms (25 cents). Pretest and posttest surveys asked about condom use among persons reporting 2 or more sex partners. RESULTS: At pretest, 57% of respondents had obtained free condoms, and 77% had used a condom during their most recent sexual encounter. When the price was raised to 25 cents, the respective percentages decreased to 30% and 64%. CONCLUSIONS: Cost is a barrier to condom use. Free condoms should be distributed to encourage their use by persons at risk for HIV and other sexually transmitted diseases.

Implementation of condom social marketing in Louisiana, 1993 to 1996.

OBJECTIVES: This article describes the implementation and impact of the first statewide condom social marketing intervention in the United States. METHODS: A statewide social marketing program made condoms freely available in 93 public health clinics, 39 community mental health centers, 29 substance abuse treatment sites, and more than 1000 businesses in neighborhoods with high rates of sexually transmitted diseases (STDs) and HIV. Surveys about condom use were conducted annually. RESULTS: Between 1994 and 1996, more than 33 million condoms were distributed without significant opposition. Over time, self-reported condom use at the last sexual encounter increased among African American women (from 28% in 1994 to 36% in 1996), particularly African American women with 2 or more sex partners (from 30% to 48%). Condom use at the last sexual encounter increased among African American men (from 40% in 1994 to an average of 54% in 1996). The number of reported sex partners did not increase. CONCLUSIONS: Condom social marketing can be successfully implemented in the United States. The widespread availability of free condoms is associated with increased condom use, particularly among persons at high risk for STDs and HIV.

Attitudes and practices of pharmacy managers regarding needle sales to injection drug users.

OBJECTIVE: To determine Louisiana pharmacy managers' attitudes and practices regarding needle and syringe sales to suspected injection drug users (IDUs) without prescriptions, and to assess which factors affect their decisions to sell nonprescription needles and syringes. DESIGN: Cross-sectional mail survey. SETTING: The six most populous cities of Louisiana. PARTICIPANTS: Pharmacy managers with active permits not affiliated with large hospitals or institutions. MAIN OUTCOME MEASURES: Selling nonprescription needles to suspected IDUs, willingness to sell nonprescription needles to suspected IDUs, and reasons for not selling nonprescription needles to suspected IDUs. RESULTS: Approximately one-fourth of the respondents reported that they had sold needles and syringes to suspected IDUs without a prescription. The most frequently cited reason for not selling was fear of increasing drug use; however, many of these pharmacists reported that they would conduct a sale if the customer had a referral from an agency or clinic. CONCLUSION: Pharmacists can assist in the prevention of HIV transmission through nonprescription needle sales to IDUs. This role can be promoted through education of pharmacists and development of referral systems for IDUs.

Networks of persons with syphilis and at risk for syphilis in Louisiana: evidence of core transmitters.

BACKGROUND AND OBJECTIVES: Differences in sociodemographic attributes and healthcare access may explain differences in regional sexually transmitted disease rates but don't fully explain why syphilis persists disproportionately in certain populations. GOAL OF THIS STUDY: To understand the behavioral epidemiology of syphilis, we conducted a social network analysis of persons with syphilis and their contacts and developed and applied a definition of core transmitters. STUDY DESIGN: We interviewed 10 index persons with primary or secondary untreated syphilis and 80 of their named sexual and social contacts. RESULTS: Fourteen (16%) of 90 interviewed persons met the definition of core transmitters, 9 of whom had past or current syphilis. The other interviewed persons had only moderately risky behaviors. Seventy-eight (42%) of the network sexual contacts were connected directly or indirectly to a core transmitter. CONCLUSION: This analysis suggests that syphilis transmission is maintained by a community with a small percentage of high-risk persons centrally placed amidst a larger group with moderately risky behavior.

Evaluation of the Gen-Probe PACE 2 assay for the detection of asymptomatic Chlamydia trachomatis and Neisseria gonorrhoeae infections in male arrestees.

BACKGROUND: The LET and Gen-Probe PACE 2 assay are used to screen male arrestees for evidence of infection with chlamydia and gonorrhea in the intake/booking area of the Jefferson Parish Correctional Center. GOAL OF THIS STUDY: To determine the accuracy of the Gen-Probe PACE 2 assay for the detection of asymptomatic infection with Chlamydia trachomatis and Neisseria gonorrhoeae infections in male arrestees. STUDY DESIGN: From December 1993 to March 1994, 196 arrestees younger than 22 years were screened with the Gen-Probe PACE 2 assay and McCoy shell vial culture for Chlamydia trachomatis. From April to October 1994, 444 arrestees of all ages were screened with the Gen-Probe PACE 2 assay and standard culture for Neisseria gonorrhoeae. The sensitivity, specificity, and predictive values of the Gen-Probe PACE 2 assay, compared with culture, were calculated with 95% confidence intervals. RESULTS: The Gen-Probe PACE 2 assay compared with culture had a sensitivity, specificity, and positive predictive value for Chlamydia trachomatis of 84%, 99%, and 93% and for Neisseria gonorrhoeae of 54%, 99.5%, and 78%. CONCLUSION: The Gen-Probe PACE 2 assay is useful for screening young males in this jail setting and is more accurate for detecting Chlamydia trachomatis compared with Neisseria gonorrhoeae.

A geographic relation between alcohol availability and gonorrhea rates.

BACKGROUND AND OBJECTIVES: The availability of alcohol measured as alcohol outlet density is associated with numerous alcohol-related outcomes in small area analysis. A number of studies suggest that high-risk sexual behavior should also be considered an alcohol-related outcome. GOAL OF THIS STUDY: To assess the geographic relationship between alcohol availability and high-risk sexual behavior at the neighborhood level. STUDY DESIGN: Ecological analysis of the geographic relation between off-premise, on-premise, and total alcohol outlet density and reported gonorrhea rates among 155 urban residential census tracts in New Orleans during 1995. RESULTS: All alcohol outlet density variables were positively related to gonorrhea rates. Off-premise outlets per square mile was most strongly related to gonorrhea rates (beta +/- SE) (beta = 0.582+/-0.073), accounting for 29% of the variance in gonorrhea rates. Interpreted as an elasticity, a 10% increase in off-sale alcohol outlet density accounts for a 5.8% increase in gonorrhea rates. Including the covariates percent black and percent unemployed to the model reduced but did not remove the effect of off-sale outlet density (beta = 0.192+/-0.047). CONCLUSIONS: These results indicate there is a geographic relationship between alcohol outlet density and gonorrhea rates at the census tract level. Although these results cannot be interpreted causally, they do justify a public health intervention as a next step in defining the relation between alcohol availability and high-risk sexual behavior.