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1.
Because certain groups at high risk for HIV/AIDS (human immunodeficiency virus/acquired immunodeficiency syndrome) come together in correctional facilities, seroprevalence was high early in the epidemic. The share of the HIV/AIDS epidemic borne by inmates of and persons released from jails and prisons in the United States (US) in 1997 was estimated in a previous paper. While the number of inmates and releasees has risen, their HIV seroprevalence rates have fallen. We sought to determine if the share of HIV/AIDS borne by inmates and releasees in the US decreased between 1997 and 2006. We created a new model of population flow in and out of correctional facilities to estimate the number of persons released in 1997 and 2006. In 1997, approximately one in five of all HIV-infected Americans was among the 7.3 million who left a correctional facility that year. Nine years later, only one in seven (14%) of infected Americans was among the 9.1 million leaving, a 29.3% decline in the share. For black and Hispanic males, two demographic groups with heightened incarceration rates, recently released inmates comprise roughly one in five of those groups'' total HIV-infected persons, a figure similar to the proportion borne by the correctional population as a whole in 1997. Decreasing HIV seroprevalence among those admitted to jails and prisons, prolonged survival and aging of the US population with HIV/AIDS beyond the crime-prone years, and success with discharge planning programs targeting HIV-infected prisoners could explain the declining concentration of the epidemic among correctional populations. Meanwhile, the number of persons with HIV/AIDS leaving correctional facilities remains virtually identical. Jails and prisons continue to be potent targets for public health interventions. The fluid nature of incarcerated populations ensures that effective interventions will be felt not only in correctional facilities but also in communities to which releasees return.  相似文献   

2.
Background: The Russian Federation and the Ukraine are among the Eastern European countries with the fastest growing number of cases of HIV. According to data from the Joint United Nations Program on HIV/AIDS, nearly 90% of newly reported HIV diagnoses in Eastern Europe in 2006 were from the Russian Federation (66%) and the Ukraine (21%). A growing number of women are infected with HIV. The impact of gender on HIV/AIDS is an important factor in understanding the development and evolution of the HIV/AIDS epidemic in Eastern Europe.Objective: The aim of this study was to assess the importance of integrating gender consideration into the creation of HIV programs and to examine the effect of gender on HIV/AIDS.Methods: Reported HIV/AIDS cases from the official epidemiological register of the Ukrainian Centre for AIDS Prevention alongside data from the Russian Federal AIDS Center were analyzed. Joint United Nations Program on HIV/AIDS country fact sheets were reviewed and analyzed, and this information was supplemented with published HIV prevalence and sexually transmitted disease case reporting information, unpublished reports, and expert evaluations.Results: Of the newly registered cases of HIV, the proportion of women rose from 13.0% in 1995 to 44.0% in 2006 in the Russian Federation, and from 37.2% in 1995 to 41.9% in 2006 in the Ukraine. There has also been a considerable increase in mother-to-child transmission of HIV since 1995. Between 1987 and 1994, the proportion of children among the people newly infected with HIV in the Ukraine was 2.2%; in 2006 it was 17.6%. In 2006, 16,078 new HIV cases were registered in the Ukraine and 39,652 new HIV cases in the Russian Federation. Large increases in the number of HIV-infected women were reported from both countries.Conclusions: The data examined in this study suggest subregional differences in the magnitude of the HIV/AIDS epidemic in the Russian Federation and the Ukraine and the importance of the impact of gender on the rapid spread of the HIV/AIDS epidemic among women and women of child-bearing age. To protect women from HIV infection, it is important to find ways to empower them by implementing policies and specific prevention measures that increase their access to knowledge about HIV/AIDS; the empowerment of women is vital to reversing the HIV/AIDS epidemic.  相似文献   

3.
To study the future course of the AIDS epidemic in Mexico City, we use an open compartmental model to forecast new AIDS cases among homosexual and bisexual males and among heterosexual males and females. For each group three compartments are defined: uninfected persons, infected but asymptomatic persons, and persons diagnosed with AIDS. It is assumed that the AIDS epidemic will follow the propagation of infectious disease model, where spread of infection is proportional to the product of the number of healthy persons and the number of infected ones. The compartmental model is represented by a system of nonlinear differential equations describing the rate of change in the number of persons in each compartment. The impact of preventive measures is explored by decreasing the probability of HIV transmission, which is one of the model parameters representing behavioral patterns. By April 1989, 491 AIDS cases had been reported in Mexico City and classified as sexually related. Our model predicts that the AIDS incidence will continue to rise in Mexico City for the foreseeable future and will spread among the heterosexual population. Decreasing the transmission probability by 10% in all groups (through education programs) will result in a decrease of 18.1% in the number of accumulated cases over a 5-year period. A 20% decrease would prevent more than 31% of the cases. We conclude that mathematical models can be valuable in predicting the spread of the AIDS epidemic and the impact of behavioral change on its spread.  相似文献   

4.

Background

Surfactant protein D (SP-D) and Mannose Binding Lectin (MBL) are collectins that have opsonic and immunoregulatory functions, are found in lung fluid and interact with the human immunodeficiency virus (HIV). We compared collectin levels in lung fluid and serum from HIV infected and normal subjects to determine if alterations in lung collectin levels were associated with HIV infection and might result in increased susceptibility to other pulmonary infections.

Methods

Blood and bronchoalveolar lavage samples were collected from 19 HIV-infected individuals and 17 HIV-uninfected individuals, all with normal chest X ray at time of study. HIV viral loads and peripheral blood CD4+ T cell counts were measured in all subjects. SP-D was measured in lung fluid, and MBL in both lung fluid and serum.

Results

SP-D levels were not significantly different in lung fluid from HIV-uninfected (median 406.72 ng/ml) and HIV-infected individuals with high CD4 count (CD4 >200) (median 382.60 ng/ml) but were elevated in HIV-infected individuals with low CD4 count (median 577.79 ng/ml; Kruskall Wallis p < 0.05). MBL levels in serum were not significantly different between HIV-uninfected and HIV-infected individuals (median 1782.70 ng/ml vs 2639.73 ng/ml) and were not detectable in lung fluid.

Conclusion

SP-D levels are increased in lung fluid from AIDS patients but not in patients with early HIV infection. MBL levels are not altered by HIV infection or AIDS. There is no evidence that altered pulmonary collectin levels result in susceptibility to infection in these patients.  相似文献   

5.
The Sverdlovsky region takes the fourth place among the 89 subjects of the Russian Federation by the number of registered cases of HIV infection. Drug addiction has reached an excessive scale in this region: according to the data of express evaluation carried out by the Regional Narcological Hospital and the Regional AIDS Center, not less than 7-8% of persons aged 15-30 years constantly use injection drugs. The large-scale epidemic of injection drug addiction has led to the rapid spread of HIV among addicts. The first penetration of HIV into this population took place in 1996 and, starting from the year 2000, rapid, development of the epidemic began, taking the character of an avalanche. The peak of new cases of HIV infection fell on 2001 (9,230 cases were registered). The concentrated stage of the epidemic development is observed in the region at present, the prevalence of HIV infection among drug addicts being 13.8%. Children born from HIV-infected drug addicted mothers now represent a new risk group due to great difficulties in the prophylaxis of the vertical virus transmission.  相似文献   

6.

Background

In sub-Saharan Africa many children live in extreme poverty and experience a burden of illness and disease that is disproportionately high. The emergence of HIV and AIDS has only exacerbated long-standing challenges to improving children’s health in the region, with recent cohorts experiencing pediatric AIDS and high levels of orphan status, situations which are monitored globally and receive much policy and research attention. Children’s health, however, can be affected also by living with HIV-infected adults, through associated exposure to infectious diseases and the diversion of household resources away from them. While long recognized, far less research has focused on characterizing this distinct and vulnerable population of HIV-affected children.

Methods

Using Demographic and Health Survey data from 23 countries collected between 2003 and 2011, we estimate the percentage of children living in a household with at least one HIV-infected adult. We assess overlaps with orphan status and investigate the relationship between children and the adults who are infected in their households.

Results

The population of children living in a household with at least one HIV-infected adult is substantial where HIV prevalence is high; in Southern Africa, the percentage exceeded 10% in all countries and reached as high as 36%. This population is largely distinct from the orphan population. Among children living in households with tested, HIV-infected adults, most live with parents, often mothers, who are infected; nonetheless, in most countries over 20% live in households with at least one infected adult who is not a parent.

Conclusion

Until new infections contract significantly, improvements in HIV/AIDS treatment suggest that the population of children living with HIV-infected adults will remain substantial. It is vital to on-going efforts to reduce childhood morbidity and mortality to consider whether current care and outreach sufficiently address the distinct vulnerabilities of these children.  相似文献   

7.

Background

New HIV infections in men who have sex with men (MSM) have increased in Switzerland since 2000 despite combination antiretroviral therapy (cART). The objectives of this mathematical modelling study were: to describe the dynamics of the HIV epidemic in MSM in Switzerland using national data; to explore the effects of hypothetical prevention scenarios; and to conduct a multivariate sensitivity analysis.

Methodology/Principal Findings

The model describes HIV transmission, progression and the effects of cART using differential equations. The model was fitted to Swiss HIV and AIDS surveillance data and twelve unknown parameters were estimated. Predicted numbers of diagnosed HIV infections and AIDS cases fitted the observed data well. By the end of 2010, an estimated 13.5% (95% CI 12.5, 14.6%) of all HIV-infected MSM were undiagnosed and accounted for 81.8% (95% CI 81.1, 82.4%) of new HIV infections. The transmission rate was at its lowest from 1995–1999, with a nadir of 46 incident HIV infections in 1999, but increased from 2000. The estimated number of new infections continued to increase to more than 250 in 2010, although the reproduction number was still below the epidemic threshold. Prevention scenarios included temporary reductions in risk behaviour, annual test and treat, and reduction in risk behaviour to levels observed earlier in the epidemic. These led to predicted reductions in new infections from 2 to 26% by 2020. Parameters related to disease progression and relative infectiousness at different HIV stages had the greatest influence on estimates of the net transmission rate.

Conclusions/Significance

The model outputs suggest that the increase in HIV transmission amongst MSM in Switzerland is the result of continuing risky sexual behaviour, particularly by those unaware of their infection status. Long term reductions in the incidence of HIV infection in MSM in Switzerland will require increased and sustained uptake of effective interventions.  相似文献   

8.
A three-stage stochastic epidemic model extending the so-called classical epidemic process to one that includes time-dependent transition probabilities is described, and a solution to the appropriate set of forward differential-difference equations is given. When an individual can move from being a susceptible to one infected with the HIV virus to one diagnosed as having AIDS, we can use this general model to describe an AIDS epidemic process. We obtain expressions for the mean and variance of the number of AIDS cases for some special cases. By comparing these with actual data, it is suggested that, for some categories of cases (in particular, children), this model might be a plausible model to describe the underlying mechanism of the AIDS epidemic.  相似文献   

9.
During the initially exponential spread of the human immunodeficiency virus (HIV—the causative agent of AIDS) the growth rate of the number of AIDS cases decreases from plus infinity to the growth rate of HIV infections. A sensitivity analysis shows that for all reasonable values of the parameters of the HIV epidemic (incubation period, initial doubling time, etc.) the effect of this positive transient becomes negligible when the annual number of AIDS cases reaches a few dozen. Necessary and sufficient conditions are given for the growth rate of the number of AIDS cases to be monotonically decreasing during the positive transient. A mildly pathological density function for the incubation period of AIDS provides an example of a growth rate of AIDS that does not decrease monotonically, even though HIV is spreading exponentially. A negative transient occurs when the growth rate of HIV begins to decrease. In this context a somewhat surprising result emerges under the assumption that the growth rate of HIV is non-increasing: the growth rate of AIDS is at all times larger than the growth rate of HIV. A logistic HIV epidemic illustrates this result, and implications for the growth of the HIV epidemic in the United States and Europe are discussed. In particular, it is shown that the positive transient must have passed by 1982 in the United States and by 1986 or 1987 for the five European countries with the largest caseloads.  相似文献   

10.
To determine the patterns of care of patients infected with the human immunodeficiency virus (HIV), data from 2 sources were analyzed. Initial data obtained from the Washington State HIV/Acquired Immunodeficiency Syndrome (AIDS) Epidemiology Unit indicate that 46% of patients with class IV AIDS were seen by physicians who reported fewer than 5 patients with AIDS, and 68% of all Washington physicians who reported treating patients with AIDS have reported only 1 patient. Subsequent data obtained from a questionnaire distributed in 4 Northwest states suggest that 74% of primary care internists and 73% of family practitioners have some experience in caring for patients with HIV infection, but most of these physicians report fewer than 6 patients in the past 2 years. Although most providers seeing large numbers of HIV-infected patients in their practices were based in the region''s major metropolitan area, 59% of the internists and 55% of the family practitioners surveyed outside of the metropolitan area had seen at least 1 HIV-infected patient in their practices. These results suggest that primary care physicians with relatively little experience treating HIV infection are providing care for a large number of HIV-infected persons. Further study is needed to determine the extent and quality of care provided.  相似文献   

11.
The analysis of the occurrence of HIV infection in adults, children and adolescents under 18 years of age on the basis of statistical data by February 1, 1997, is presented. The total number HIV-infected persons registered by this date was 6,232; among them 902 (14.5%) were children and adolescents. 267 children were infected in the hospital focus of HIV infection; of these, 80 children (30%) died of AIDS during the period of 1989-1997. In 1992 only 16 adolescents, HIV infected were registered, while in 1995 the number of HIV-infected adolescents was 34, in 1996 their number rose to 144 and in 1997, to 435. The main cause of adolescent infections (80%) was the intravenous injection of narcotic drugs.  相似文献   

12.
The only long-term and cost-effective solution to the human immunodeficiency virus (HIV) epidemic in the developing world is a vaccine that prevents individuals from becoming infected or, once infected, from passing the virus on to others. There is currently little hope for an AIDS vaccine. Conventional attempts to induce protective antibody and CD8(+) lymphocyte responses against HIV and simian immunodeficiency virus (SIV) have failed. The enormous diversity of the virus has only recently been appreciated by vaccinologists, and our assays to determine CD8(+) lymphocyte antiviral efficacy are inadequate. The central hypothesis of a CTL-based vaccine is that particularly effective CD8(+) lymphocytes directed against at least five epitopes that are derived from regions under functional and structural constraints will control replication of pathogenic SIV. This would be somewhat analogous to control of virus replication by triple drug therapy or neutralizing antibodies.  相似文献   

13.
We have examined cross-clade HIV-specific cytotoxic T-lymphocyte (CTL) activity in peripheral blood of eight Zambian individuals infected with non-B-clade human immunodeficiency virus type 1 (HIV-1). Heteroduplex mobility assay and partial sequence analysis of env and gag genes strongly suggests that all the HIV-infected subjects were infected with clade C HIV-1. Six of eight C-clade HIV-infected individuals elicited CTL activity specific for recombinant vaccinia virus-infected autologous targets expressing HIV gag-pol-env derived from B-clade HIV-1 (IIIB). Recognition of individual recombinant HIV-1 B-clade vaccinia virus-infected targets expressing gag, pol, or env was variable among the patients tested, indicating that cross-clade CTL activity is not limited to a single HIV protein. These data demonstrate that HIV clade C-infected individuals can mount vigorous HIV clade B-reactive CTL responses.  相似文献   

14.
HIV-associated nephropathy (HIVAN) is a clinicopathologic entity characterized by heavy proteinuria, absence of edema and an irreversible decline in renal function. Findings on renal biopsy include: collapsed glomerular capillaries; visceral glomerular epitheliosis; microcystic tubules; mesangial prominence; and endothelial tubuloreticular inclusions. Early in the AIDS epidemic, HIVAN was the predominant glomerular lesion observed in HIV-infected patients. It is being increasingly recognized, especially in Caucasian populations, that a variety of immune complex-mediated lesions such as membranoproliferative glomerulonephritis, proliferative glomerulonephritis and IgA nephropathy are associated with HIV infection. In this review we present two cases: one patient whose first presentation of AIDS was end-stage renal disease, who on biopsy was found to have HIVAN, and the second, who was infected with HIV, and on biopsy was found to have hepatitis C-related hepatitis C related membranoproliferative glomerulonephritis. We also review the current literature on HIVAN and HIV-associated immune complex diseases (HIVICDs). Each case illustrates an important clinical point. The first that renal disease can be the first manifestation of HIV infection and the second that HIV-infected patients may develop immune complex related renal diseases, some of which may be potentially treatable.  相似文献   

15.
Human immunodeficiency virus (HIV) type 1 subtype B sequences (whole envelope and the p17 region of gag) were obtained from peripheral blood mononuclear cell samples collected in 1981 from seven HIV-infected U.S. individuals and in 1982 from one infected Canadian resident. Phylogenetic and nucleotide distance analyses were performed by using database sequences representing North American strains collected from 1978 to 1995. The estimated phylogeny was starlike, with early strains represented on different lineages. When sequences were grouped by years of collection, nucleotide distance comparisons demonstrated an increase in diversity over time and indicated that contemporary strains are more closely related to early epidemic strains than to each other. Using a recently developed likelihood ratio reduction procedure, the date of origin of the U.S. epidemic was estimated to be 1968 +/- 1.4 years. A coalescent approach was also used to estimate the population history of the U.S. subtype B epidemic. Our analyses provide new information that implies an exponential growth rate from the beginning of the U.S. HIV epidemic. The dating results suggest a U.S. introduction date (or date of divergence from the most recent common ancestor) that precedes the date of the earliest known AIDS cases in the late 1970s. Furthermore, the estimated epidemic growth curve shows a period of exponential growth that preceded most of the early documented cases and also indicates a leveling of prevalence rates in the recent past.  相似文献   

16.
The analysis of the dynamics of the epidemic process for 10 years made it possible to find out the presence of two separate epidemic waves of HIV infection. The first wave (1987-1994) was manifested as the slow type of the development of the epidemic, characterized mainly by sexual transmission. During this period 398 persons with HIV infection were detected, 24 persons were found to have AIDS; of these, 13 persons died. The second epidemic wave began in 1995 and was due to the spread of HIV among users of drugs introduced by injection. By the end of 1995 the number of HIV carriers was 34 times greater than that of 1994, reaching 1490 persons. In 1996-1997 this figure increased 8 times (annually). The number of AIDS patients rose to 420 persons. The most unfavorable regions with respect to HIV infection and AIDS morbidity were determined. The western regions of the Ukraine were noted to be in a more favorable situation in this respect with infection indices being lower more than 30 times. Up to 80% of all infected persons were found to be addicts introducing drugs intravenously. Growing morbidity in sexually transmitted disease, particularly in syphilis, contributed to the deterioration of the epidemiological situation. The conclusion was made on the necessity of introducing new prophylactic programs and expanding current ones. The signs of stabilization in Odessa and Nikolayev were observed; in these cities pilot programs aimed at the strategy of the "decrease of harm" have been introduced (in collaboration with UNAIDS) since 1996.  相似文献   

17.
According to the Joint UN Programme on HIV/AIDS report, AIDS will cause early death in as many as half of the teenagers living in southern Africa. In Botswana, demographers have predicted that two-thirds of the 15-year-olds will die of AIDS before the age of 50. In terms of global estimates, the report indicated that there are 34.3 million people infected with HIV, of whom 1.3 million are children under the age of 15. The impact of the AIDS epidemic is accounted for in the erosion of all key measures of a nation's health, especially in much of sub-Saharan Africa. These key measures include economic development, educational attainment, and child survival. Although there are a few success stories in the countries of Uganda and Thailand, which show that strong prevention campaigns and increased condom use help in curbing the epidemic, the report revealed the need for a massive increase in political will.  相似文献   

18.
This paper presents a sex-structured model for heterosexual transmission of HIV/AIDS in which the population is divided into three subgroups: susceptibles, infectives and AIDS cases. The subgroups are further divided into two classes, consisting of individuals involved in high-risk sexual activities and individuals involved in low-risk sexual activities. The model considers the movement of individuals from high to low sexual activity groups as a result of public health educational campaigns. Thus, in this case public health educational campaigns are resulting in the split of the population into risk groups. The equilibrium and epidemic threshold, which is known as the basic reproductive number (R0), are obtained, and stability (local and global) of the disease-free equilibrium is investigated. The model is extended to incorporate sex workers, and their role in the spread of HIV/AIDS in settings with heterosexual transmission is explored. Comprehensive analytic and numerical techniques are employed in assessing the possible community benefits of public health educational campaigns in controlling HIV/AIDS. From the study, we conclude that the presence of sex workers enlarges the epidemic threshold R0, thus fuels the epidemic among the heterosexuals, and that public health educational campaigns among the high-risk heterosexual population reduces R0, thus can help slow or eradicate the epidemic.  相似文献   

19.
Through a glass, darkly: data and uncertainty in the AIDS debate   总被引:1,自引:0,他引:1  
The HIV/AIDS epidemic is the greatest threat to development in much of Africa. It is already the main cause of death in many countries, especially those in Southern Africa. However there is an absence of solid data on the scale and scope of the disease and how it is evolving. In this article we discuss the data on the epidemic – where it comes from and how it is presented. We note the limitations of the use of antenatal clinic surveys – which provide the bulk of our information.
We then turn to the evidence of impact. The paper shows that the long incubation period between infection and illness means that it takes time for HIV infections to turn into AIDS cases, and AIDS cases to translate into deaths with all the consequences of orphaning, poverty and changing population structures. Furthermore it means that once the HIV prevalence has peaked, AIDS impact will take years to work through – this epidemic is a 'long-wave' event.
The paper is premised on the view that HIV causes AIDS and AIDS causes death. It notes that insufficient and/or unreliable data have allowed leaderships to deny the scope and scale of the problem and that this is unacceptable. However it is incumbent on all to accept the moral responsibility for and the moral consequences of their work, and this includes those who gather, interpret and use the data.  相似文献   

20.
Previous studies have revealed that HIV-infected individuals possess circulating CD4(+)CD8(+) double-positive (DP) T cells specific for HIV Ags. In the present study, we analyzed the proliferation and functional profile of circulating DP T cells from 30 acutely HIV-infected individuals and 10 chronically HIV-infected viral controllers. The acutely infected group had DP T cells that showed more proliferative capability and multifunctionality than did both their CD4(+) and CD8(+) T cells. DP T cells were found to exhibit greater proliferation and higher multifunctionality compared with CD4 T cells in the viral controller group. The DP T cell response represented 16% of the total anti-HIV proliferative response and >70% of the anti-HIV multifunctional response in the acutely infected subjects. Proliferating DP T cells of the acutely infected subjects responded to all HIV Ag pools with equal magnitude. Conversely, the multifunctional response was focused on the pool representing Nef, Rev, Tat, VPR, and VPU. Meanwhile, the controllers' DP T cells focused on Gag and the Nef, Rev, Tat, VPR, and VPU pool for both their proliferative and multifunctional responses. Finally, we show that the presence of proliferating DP T cells following all HIV Ag stimulations is well correlated with proliferating CD4 T cells whereas multifunctionality appears to be largely independent of multifunctionality in other T cell compartments. Therefore, DP T cells represent a highly reactive cell population during acute HIV infection, which responds independently from the traditional T cell compartments.  相似文献   

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