Demographic, clinical and social factors associated with human immunodeficiency virus infection and other sexually transmitted diseases in a cohort of women from the United Kingdom and Ireland. MRC Collaborative Study of women with HIV.
BACKGROUND: Clinical experience suggests many women with HIV infection have experienced no other sexually transmitted diseases (STD). Our objective was to test the hypothesis that a substantial proportion of women with HIV infection in the United Kingdom and Ireland have experienced no other diagnosed STD and to describe the demographic, clinical and social factors associated with the occurrence of other STD in a cohort of HIV infected women. METHOD: Analysis of cross-sectional baseline data from a prospective study of 505 women with diagnosed HIV infection. The setting was 15 HIV treatment centres in the United Kingdom and Ireland. The main outcome measures were occurrence of other STD diagnosed for the first time before and after HIV diagnosis. Data were obtained from interview with women and clinic notes. We particularly focused on occurrence of gonorrhoea, chlamydia and trichomoniasis after HIV diagnosis, as these are the STD most likely to reflect recent unprotected sexual intercourse. RESULTS: The women were mainly infected via heterosexual sex (n = 304), and injection drug use (n = 174). 151 were black Africans. A total of 250 (49.5%) women reported never having been diagnosed with an STD apart from HIV, 255 (50.5%) women had ever experienced an STD besides HIV, including 109 (21.6%) who had their first other STD diagnosed after HIV. Twenty-five (5%) women reported having had chlamydia, gonorrhoea or trichomoniasis diagnosed for the first time after HIV diagnosis, possibly reflecting unprotected sexual intercourse since HIV diagnosis. In all 301 (60%) women reported having had sex with a man in the 6 months prior to entry to the study. Of these, 168 (58%) reported using condoms 'always', 66(23%) 'sometimes' and 56 (19%) 'never'. CONCLUSIONS: Half the women in this study reported having never experienced any other diagnosed STD besides HIV. However, after HIV diagnosis most women remain sexually active and at least 5% had an STD diagnosed which reflect unprotected sexual intercourse. (+info)
Incidence of acquired immunodeficiency syndrome (AIDS)-related Kaposi's sarcoma in the Aquitaine Cohort, France, 1988-1996. Groupe d'Epidemiologie Clinique du SIDA en Aquitaine.
OBJECTIVE: To assess secular trends of the incidence of Kaposi's sarcoma (KS) between 1988 and 1996 in the Aquitaine Cohort of human immunodeficiency virus type 1 (HIV1)-infected subjects (southwestern France). METHODS: Adults of both sexes of all HIV-transmission categories were included. We distinguished between incident and prevalent KS and in case of multiple acquired immunodeficiency syndrome (AIDS) defining illnesses between initial or subsequent KS. Only incident KS were considered for annual incidence rate calculation. RESULTS: Overall, 21.2% (356/1678) of homosexuals and 1.9% (58/3030) of the other patients were diagnosed with KS over time. Although there was a sharp decrease in 1996 for initial KS, the annual incidence rate of KS was stable over time in the overall cohort as well as in homosexuals (4.3% per year on the average for KS as an initial AIDS-defining illness and 2.1% per year for subsequent KS in homosexuals). The median CD4+ cell count at the time of diagnosis of KS was 56 per mm3 (78 for initial KS, 14 for subsequent KS), with no significant variation over time. CONCLUSION: In the Aquitaine Cohort, the annual incidence of KS has remained stable between 1988 and 1995 with a recent decline in 1996, only for initial KS, while case management of HIV-infected subjects changed drastically. (+info)
Hygiene behaviour in rural Nicaragua in relation to diarrhoea.
BACKGROUND: Childhood diarrhoea is a leading cause of morbidity and mortality in Nicaragua. Amongst the risk factors for its transmission are 'poor' hygiene practices. We investigated the effect of a large number of hygiene practices on diarrhoeal disease in children aged <2 years and validated the technique of direct observation of hygiene behaviour. METHODS: A prospective follow-up study was carried out in a rural zone of Nicaragua. From the database of a previously conducted case-control study on water and sanitation 172 families were recruited, half of which had experienced a higher than expected rate of diarrhoea in their children and the other half a lower rate. Hygiene behaviour was observed over two mornings and diarrhoea incidence was recorded with a calendar, filled out by the mother, and collected every week for 5 months. RESULTS: Of 46 'good' practices studied, 39 were associated with a lower risk of diarrhoea, five were unrelated and only for two a higher risk was observed. Washing of hands, domestic cleanliness (kitchen, living room, yard) and the use of a diaper/underclothes by the child had the strongest protective effect. Schooling (>3 years of primary school) and better economic position (possession of a radio) had a positive influence on general hygiene behaviour, education having a slightly stronger effect when a radio was present. Individual hygiene behaviour appeared to be highly variable in contrast with the consistent behaviour of the community as a whole. Feasible and appropriate indicators of hygiene behaviour were found to be domestic cleanliness and the use of a diaper or underclothes by the child. CONCLUSION: A consistent relationship between almost all hygiene practices and diarrhoea was detected, more schooling producing better hygiene behaviour. The high variability of hygiene behaviour at the individual level requires repeated observations (at least two) before and after the hygiene education in the event one wants to measure the impact of the campaign on the individual. (+info)
Virulence evolution in a virus obeys a trade-off.
The evolution of virulence was studied in a virus subjected to alternating episodes of vertical and horizontal transmission. Bacteriophage f1 was used as the parasite because it establishes a debilitating but non-fatal infection that can be transmitted vertically (from a host to its progeny) as well as horizontally (infection of new hosts). Horizontal transmission was required of all phage at specific intervals, but was prevented otherwise. Each episode of horizontal transmission was followed by an interval of obligate vertical transmission, followed by an interval of obligate horizontal transmission etc. The duration of vertical transmission was eight times longer per episode in one treatment than in the other, thus varying the relative intensity of selection against virulence while maintaining selection for some level of virus production. Viral lines with the higher enforced rate of infectious transmission evolved higher virulence and higher rates of virus production. These results support the trade-off model for the evolution of virulence. (+info)
Dirt and diarrhoea: formative research in hygiene promotion programmes.
Investment in the promotion of better hygiene for the prevention of diarrhoeal diseases and as a component of water and sanitation programmes is increasing. Before designing programmes capable of sustainably modifying hygiene behaviour in large populations, valid answers to a number of basic questions concerning the site and the intended beneficiaries have to be obtained. Such questions include 'what practices favour the transmission of enteric pathogens?', 'what advantages will be perceived by those who adopt safe practices?' and 'what channels of communication are currently employed by the target population?' A study of hygiene and diarrhoea in Bobo-Dioulasso, Burkina Faso, used a mixture of methods to address such questions. This paper draws on that experience to propose a plan of preliminary research using a variety of techniques which could be implemented over a period of a few months by planners of hygiene promotion programmes. The techniques discussed include structured observation, focus group discussions and behavioural trials. Modest investment in such systematic formative research with clear and limited goals is likely to be repaid many times over in the increased effectiveness of hygiene promotion programmes. (+info)
The quality of immunization data from routine primary health care reports: a case from Nepal.
Reported high immunization coverage achieved in Nepal over the last ten years is expected to reduce child mortality in the country. The present study, carried out in hill district in mid-west Nepal, aimed to assess the quality of immunization data in Nepal. The number of children who received different vaccines during one year was obtained from three sources: 1) the Immunization REgister of three Primary Health Care Service Outlets (PHCSOs) where each immunized child is recorded; 2) monthly PHC Reports, which are based on the Immunization Register; 3) monthly DHO Reports, which are based on the above PHC Reports (the DHO reports are the source of official statistics). The number of children in the PHC Reports was higher than the number in the Immunization REgisters for all vaccines. The number of immunizations in the DHO Reports was higher than the number in the PHC Reports for BCG, DPT, and measles; the number was lower for poliomyelitis. The overall number of immunizations was higher in the DHO Reports than in the Immunization Registers, by 31% for BCG, 44% for DPT, 155% for polio, and 71% for measles. We conclude that the official report overestimates the immunization coverage in the district. The immunization programme, therefore, might not result in the expected reduction of morbidity and mortality despite the investment in the programme and reported high coverage. (+info)
Evolution and biological characterization of human immunodeficiency virus type 1 subtype E gp120 V3 sequences following horizontal and vertical virus transmission in a single family.
It has been suggested that immune-pressure-mediated positive selection operates to maintain the antigenic polymorphism on the third variable (V3) loop of the gp120 of human immunodeficiency virus type 1 (HIV-1). Here we present evidence, on the basis of sequencing 147 independently cloned env C2/V3 segments from a single family (father, mother, and their child), that the intensity of positive selection is related to the V3 lineage. Phylogenetic analysis and amino acid comparison of env C2/V3 and gag p17/24 regions indicated that a single HIV-1 subtype E source had infected the family. The analyses of unique env C2/V3 clones revealed that two V3 lineage groups had evolved in the parents. Group 1 was maintained with low variation in all three family members regardless of the clinical state or the length of infection, whereas group 2 was only present in symptomatic individuals and was more positively charged and diverse than group 1. Only virus isolates carrying the group 2 V3 sequences infected and induced syncytia in MT2 cells, a transformed CD4(+)-T-cell line. A statistically significant excess of nonsynonymous substitutions versus synonymous substitutions was demonstrated only for the group 2 V3 region. The data suggest that HIV-1 variants, possessing the more homogeneous group 1 V3 element and exhibiting the non-syncytium-inducing phenotype, persist in infected individuals independent of clinical status and appear to be more resistant to positive selection pressure. (+info)
Identification of MaTu-MX agent as a new strain of lymphocytic choriomeningitis virus (LCMV) and serological indication of horizontal spread of LCMV in human population.
In this study we elucidated the molecular character of MaTu-MX, previously described as an unusual transmissible agent. Amino acid sequencing of peptides generated from a 58-kDa MX-related protein purified from MaTu human carcinoma cells allowed us to identify it as a nucleoprotein (NP) of lymphocytic choriomeningitis virus (LCMV). Northern blot analysis detected LCMV-specific RNAs in MaTu cells. Comparative immunoprecipitations showed cross-reactivity between NP of LCMV strain WE and MX NP. Using RT-PCR, we have cloned MX NP cDNA. According to sequence comparison, MX LCMV is as closely related to both LCMV strains WE and Armstrong as these strains are to one another. Based on this finding we propose that MX is a new strain of LCMV. We also showed that the stability of MX NP in MaTu cells is very high and that the virus is transmissible by cell-to-cell contact or by cell-free extract to human HeLa and monkey Vero cells, but not to human AGS, canine MDCK, mouse NIH 3T3, and hamster CHO cells. Finally, employing MX LCMV NP in immunoprecipitation and solid-phase radioimmunoassay, we found 37.5% prevalence of anti-LCMV antibodies in human sera, suggesting possible horizontal spread of the virus in the human population. (+info)