The impact of project closure on HIV incidence and mortality in a cohort of couples in Lusaka, Zambia.

The objective of this study was to assess the impact of temporary closure of an HIV research clinic on the health of study participants. Primary data were collected quarterly from couples enrolled in research studies at an established HIV study site. There were 632 participating couples enrolled when the project closed, 475 of whom returned when it re-opened six months later. HIV sero-incidence, mortality rates and risk-taking behaviours were compared before and during the closure. Perceived impact of the closure was measured in returning participants. Demographic data collected at the last pre-closure study visit were used to look at the differences between returning and non-returning study participants. Serologic data from those who returned were compared pre- and post-closure to examine changes in HIV incidence. Mortality rates were estimated from reported deaths, and were compared pre- and during project closure. Perceptions of the impact of the closure among returning participants were examined through an interviewer administered questionnaire. It was found that couples who returned were not demographically different from couples who did not return. Most participants reported no problems with finding alternate sources of condoms and the incidence of HIV did not change significantly during the closure. Eighty-four percent respondents reported that the closure had a negative impact on them, 87% of whom rated loss of medical care as the main impact. The mortality rate among HIV-positive participants doubled from 6.7/100 person years to 12.4/100 person years during the closure (p=0.01). Results indicate that couples voluntary counselling and testing (CVCT) established durable risk-reduction behaviours that persisted during project closure. ThIn ae loss of healthcare was perceived as the most negative impact on participants, reflected in increased mortality rates. Research projects should make transition plans and budget for mechanisms to reduce the negative impact on participants of project closures.

[A method for estimating the prevalence of mammary Staphylococcus aureus and Streptococcus agalactiae infections in herds based on an examination of bulk milk samples]. / Metoda odhadu prevalence intramamárních infekcí Staphylococcus aureus a Streptococcus agalactiae ve stádech na základe vysetrení bazénových vzorku.

Parallel quantitative determination executed in 92 herds at 107 sampling dates was focused on the counts of major pathogens (Staphylococcus aureus, Streptococcus agalactiae) in bulk milk samples and on the prevalence of the above pathogens in a herd by examination of individual milk samples. The counts of main pathogens were also determined in terms of quantity in rinsing water before milking and in bulk samples in 5 herds with pipeline milking. Tab. I shows the qualitative analysis of the relation. Sensitivity of the method is satisfactory for the pathogens observed (95% and 91%, resp.), but method is less specific for Staph. aureus (67% against 92% Str. agalactiae). Figs. 1 and 2 show coordinate graphs of the results obtained while Figs. 3 and 4 document the distribution of frequency of the particular values in data sets. The values do not exhibit normal distribution (P < 0.01). Spearman's coefficient of rank correlation of bulk milk and individual examinations amounted to 0.823 and 0.900 for Staph. aureus and Str. agalactiae, respectively. Four mathematical models were tested in the course of quantitative analysis, describing the relation between bulk milk examination and individual examination: (1) linear regression, (2) linear regression with fixed starting point, (3) logarithmic regression and (4) irrational function. A model based on the equation of irrational function (4) was found to be best: y = a + bx + c square root of x + k +/- a1 + i(t)c1 square root of x + k1. Tab. II shows the parameters of the equation for examined microorganisms. Correlation coefficients for the above equation are r = 0.733 and r = 0.842 for Staph. aureus and Str. agalactiae, respectively. Prediction curves (Figs. 5 to 8) and confidence regions of prediction curves were also determined for the best model, and a prediction table was constructed (Tab. III). It was confirmed that the milking machines were not a significant source of direct contamination of bulk milk samples with the examined pathogens (Tab. V).