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Background Helminths have profound effects on the immune response, allowing long-term survival of parasites with minimal damage to the host. Some of these effects “spill-over”, altering responses to non-helminth antigens or allergens. It is suggested that this may lead to impaired responses to immunizations and infections, while conferring benefits against inflammatory responses in allergic and autoimmune disease. These effects might develop in utero, through exposure to maternal helminth infections, or through direct exposure in later life. Purpose To determine the effects of helminths and their treatment in pregnancy and in young children on immunological and disease outcomes in childhood. Methods The trial has three randomized, double-blind, placebo-controlled interventions at two times, in two people: a pregnant woman and her child. Pregnant women are randomized to albendazole or placebo and praziquantel or placebo. At age 15 months their children are randomized to three-monthly albendazole or placebo, to continue to age five years. The proposed designation for this sequence of interventions is a 2 × 2(×2) factorial design. Children are immunized with BCG and against polio, Diphtheria, tetanus, Pertussis, Haemophilus, hepatitis B and measles. Primary immunological outcomes are responses to BCG antigens and tetanus toxoid in whole blood cytokine assays and antibody assays at one, three and five years of age. Primary disease outcomes are incidence of malaria, pneumonia, diarrhoea, tuberculosis, measles, vertical HIV transmission, and atopic disease episodes, measured at clinic visits and twice-monthly home visits. Effects on anaemia, growth and intellectual development are also assessed. Conclusion This trial, with a novel design comprising related interventions in pregnant women and their offspring, is the first to examine effects of helminths and their treatment in pregnancy and early childhood on immunological, infectious disease and allergic disease outcomes. The results will enhance understanding of both detrimental and beneficial effects of helminth infection and inform policy.

Intestinal helminth prevalence is best determined by using multiple stool samples from each subject, but this may be difficult in the clinic or hospital setting. We used a range of well-established parasitological techniques in a study of interactions between helminth infestation and HIV in a cohort of 412 HIV-infected people in Entebbe, Uganda. Analysis of a single stool sample underestimated helminth prevalence, especially of low-intensity infections, but a combination of Kato-Katz smear, formol-ether concentration (FEC), charcoal culture for Strongyloides and a serum enzyme-linked immunosorbent assay for Schistosoma mansoni antigen (CAA) increased diagnostic yield. Helminths were diagnosed in 23% patients by FEC alone, 35% by FEC and Kato-Katz, 39% by FEC, Kato-Katz and charcoal culture and 49% by a combination of all three tests plus CAA. Performing a range of techniques on a single sample may enhance the detection of parasites. Techniques vary in their sensitivity for different helminths so the appropriate choice of techniques depends on which parasite species are being sought.

We implemented social marketing of pre-packaged treatment for men with urethral discharge ( Clear Seven) in Uganda, and studied its feasibility, acceptability and effectiveness as a possible means to treat STDs and thereby prevent HIV. Clear Seven was distributed at private health care outlets in three rural districts and two divisions of the capital. Comparisons were made with a pre-intervention period in the same sites plus one additional rural district. There were almost universally positive attitudes to Clear Seven. Cure rate (84% versus 47%), treatment compliance (93% versus 87%), and condom use during treatment (36% versus 18%) were significantly higher among Clear Seven users ( n=422) than controls ( n=405). Partner referral was similar but fewer Clear Seven partners were symptomatic when seeking treatment. Distribution of socially marketed pre-packaged treatment for male urethritis should be expanded in sub-Saharan Africa. Consideration should be given to developing similar kits for women.

We compared HIV-1 RNA levels using the nucleic acid sequenced based amplification (NASBA) test kit in 2 samples taken one year apart from participants infected with env subtype A or D in a population-based cohort in Uganda. Fifty participants were infected with subtype A and 70 with subtype D. HIV-1 RNA levels were significantly higher in subtype D unadjusted ( P = 0.001), and after adjusting for age, gender, and CD4 count ( P < 0.001). Eighty-six participants had HIV-1 RNA measurements in both years and 67 (78%) were within one log10 of their result a year before. There was no relationship between the difference in log viral load and proportion of CD4 change. Individuals infected with subtype D had a higher average increase in viral load and this was statistically significant if adjusted for baseline levels and CD4 count ( P = 0.015).

We aimed to assess the acceptability of a variety of formulations of female-controlled methods of protection against HIV and STDs among men and women in south-western Uganda. Pilot interviews were carried out with 50 men and 55 women and 25 focus group discussions (FGDs) were held with 138 women and 42 men. The female condom, foaming tablets, sponge, foam, gel and film were demonstrated to 146 women and 35 of their male partners, who then tried out 2 of the products. They were interviewed 7 times during the course of 5 months. At the end experiences were evaluated during a second series of FGDs. Sixty-five (45%) women completed the trial. The main reasons for non-completion were related to geographical mobility. Product preference after the initial demonstration was similar to that at the end of the trial. The most popular formulations were the sponge (25% of the women), foaming tablets (23%), and the female condom (19%). The foam was of medium popularity (16%). The gel (9%) and film (7%) were least popular. Ten per cent of the women and 14% of the men reported products interfering with sexual enjoyment; 24% of the women and 67% of the men said products increased enjoyment. 'Dry sex' is not popular in this area and increased lubrication was an important determinant of acceptability. Age, level of education and location did have some effect on preference. Although secrecy was a dominant theme in the FGDs, 87% of the women had informed their partners by the end of the trial. The products were generally well received. Female control was an important issue for both sexes. Male attitudes were ambivalent because female ownership of products increased women's control. Although they have clear preferences, women appear to accept the products generally and might use a single available product just as readily if choice was limited, as long as it conforms to general cultural preferences, such as those relating to wet/dry sex.

The objective was to estimate the likely percentage of HIV infections that may be attributable to one-off partnerships (such as those between female sex workers and their clients) and longer-term partnerships in rural Uganda. This was addressed by the application of a microsimulation model (SimulAIDS) of the transmission dynamics of HIV infection, drawing on data from a population cohort of 10,000 in rural Uganda. For a scenario reproducing documented characteristics of the study population in 1990, when adult HIV prevalence was 9%, and during subsequent follow up (1990-1994), when adult HIV incidence was 8 per 1000 person-years, the percentage of HIV infections in men (women) attributed to one-off partnerships decreased from 96% (26%) during 1980 to 67% (8%) in 1989 and 22% (5%) in 1994. Reducing HIV transmission between one-off partners early in an HIV epidemic may substantially limit the potential for the spread of HIV infection. At a later phase, prevention must also focus on control of transmission between longer-term HIV-discordant partners.This paper presents results of a study using a simulation model in estimating the likely percentage of HIV infections that may be attributable to one-off partnerships (e.g., female sex workers and their clients) and longer-term partnerships among the rural population of Uganda. The study adopted SimulAIDS, an age-structured microsimulation model of the HIV infection dynamics along with ulcerative and non-ulcerative sexually transmitted diseases. Data obtained from the 10,000 cohort population reflected a decline in the incidence of HIV in adults between 1990 and 1994, a result which could be attributed to one-off sexual partnerships in 1980, 1984, 1989, 1994, and 1999. The study supports that minimizing transmission of HIV from short-term sexual partnerships during early stage of the disease could have a strong impact on the reduction in the spread of HIV infection.

The study was based in south-west Uganda where significant differences in HIV prevalence have been found between urban and rural areas. Longitudinal data collected in a diary format was used to determine the extent to which high-risk men and women living in a truck stop/trading town had sexual contact with people from surrounding rural areas and a nearby fishing village. Study participants were 143 men, 75 of whom were resident in the town, 40 in a fishing village and 28 in rural areas, and 81 women, of whom 47 were resident in the town, 25 in the fishing village and 9 in a rural area. During 1687 man weeks the 143 men made 3149 trips and had 5189 sexual contacts. Ninety-two per cent of these sexual contacts occurred in the man's current place of residence and 21% were with a new partner. The 81 women participated for 1280 women weeks during which they recorded 6378 sexual contacts. Women who lived in the fishing village and the rural area had around 90% of their contacts with local men while those who lived in the town fell into 3 categories: women who charged a relatively high price for commercial sex had only 11% of contacts with men living in the town, while those who charged a tenth of the price had 71% of contacts with town men. The small number of women who fell into an intermediate category, in terms of price, had sexual contact with a wide variety of men. These findings show that there is little scope for HIV infection to spread between different residential or occupational groups. This may help to explain how large differences in HIV seropositivity between neighbouring localities can be maintained for long periods, despite considerable social and economic mixing between groups and high levels of sexual partner change within groups.In southwest Uganda, there is concern that sexual mixing between rural areas with low HIV prevalence and urban areas with high HIV prevalence will produce uniformly high rates of HIV. To determine the extent of such mixing, a prospective study was conducted in a trading town on the trans-African highway with a steady flow of male truckers, an agricultural hinterland to the west, and a fishing village to the east. A total of 143 men recruited largely from bars and 81 women reported to be sexually promiscuous kept records of their sexual contacts over a 6-month period. During 1687 man-weeks of observation, the men made 3149 road trips and had 5189 sexual contacts; 92% of these contacts occurred in the men's place of residence and 21% involved a new partner. 59% of town men's sexual contacts, 61% reported by men in the fishing village, and 52% of those in rural areas involved casual partners. An additional 6378 sexual encounters were recorded during 1280 woman-weeks. Close to 90% of women's sexual contacts in the 2 rural areas involved local men. Among the highest-paid town commercial sex workers, only 11% of sexual contacts involved men from the town; in contrast, 71% of sexual encounters among town women who charged only 10% the price of their more expensive counterparts were with local men. Serologic testing of a subset of 75 men and 52 women yielded HIV prevalences of 28% and 52%, respectively. The distinct sexual networks identified in this study suggest it is unlikely that rates of HIV infection in the rural areas will reach those in nearby trading towns.

In the article by Harvey et al. the evaluation procedure of the drama-based AIDS education intervention conducted in KwaZulu Natal South Africa was described. It is noted that the programs evaluation took the form of a randomized community intervention trial using seven schools each in the intervention and control groups. Overall Harvey et al. point out that there is a dearth in the literature of evaluated AIDS education programs in Africa. Although this paper from KwaZulu Natal contributes significantly to the body of evidence that suggests that AIDS education in African schools works it should be noted that the statistical methods adopted to evaluate the program may have exaggerated its impact. Further explanation indicates that the analysis of the KwaZulu Natal study took individual students rather than schools as the units of randomization. Thus the analysis would have underestimated the standard error of the intervention effect resulting in confidence intervals that are too narrow and P values that are too small. In view of this it is recommended that Harvey et al. consider conducting a re-analysis of the data using a t-test or randomization test.