Acquired immunodeficiency syndrome in a heterosexual population in Zaire

HIV / AIDS as a model for emerging infectious disease: origin, dating and circumstances of an emblematic epidemiological success

In June 1981, the Centers for Disease Control (CDC) "Morbidity and Mortality Weekly Report" described the first cases of what was to be known as the Acquired Immunodeficiency Syndrome (AIDS). Two years later, the agent responsible for the disease, the human immunodeficiency virus (HIV), was identified. Since then, according to the World Health Organization an estimated 40 million people have died from the disease. Where does this virus come from, and why such an emergence in the late 20^th century? These are the questions that it is now possible to answer in large part thanks to the numerous studies published over a little more than three decades. As with other emerging infectious diseases, initial cross-species transmission from an animal reservoir and subsequent favorable sociological factors associated with the evolution of human societies have led to the spread of a dramatic disease, for which no vaccine is presently available.

Reductions in HIV incidence are likely to increase the importance of key population programmes for HIV control in sub-Saharan Africa

INTRODUCTION

An efficient HIV response requires that resources be focussed on effective interventions for those most at risk of acquiring and transmitting infection. As HIV epidemics evolve the distribution of HIV across key and other populations will change. Here, the epidemiological concepts underpinning these changes are described and the importance of appropriate allocation of effective interventions is discussed.

DISCUSSION

In many sub-Saharan African countries HIV epidemics have been categorized as "generalized," and HIV testing, treatment and prevention interventions have focussed on the "general" population. As HIV epidemics are better controlled the relative importance of "key" populations will increase, dominating the ongoing burden of disease and providing the potential for repeated outbreaks of HIV if interventions are relaxed. The basic reproductive number (R0 ) describes the potential for an infectious disease to spread at the boundary of invasion or elimination, whereas the effective reproduction number (Rt ) describes the current potential for spread. Heterogeneity in risk means that while Rt is temporarily below one and prevalence declining, the R0 can remain above one, preventing eventual elimination. Patterns of HIV acquisition are often used to guide interventions but inadequately capture the transmission dynamics of the virus and the most efficient approach to controlling HIV. Risks for HIV acquisition are not identical to risks for HIV transmission and will change depending on the epidemiological context. In addition to the challenges in measuring HIV transmission dynamics, there is a tension between using epidemiology to drive the HIV response and the social and political realities constraining how programmes and providers can practically and appropriately focus on key populations and maintain political support. In addition to being well focussed, interventions need to be effective and cost-effective, which requires a better understanding of packages of interventions rather than specific tools.

CONCLUSIONS

Continued control of HIV will increasingly rely on resources, programmes and interventions supporting key populations. Current epidemiological and programmatic approaches for key populations in sub-Saharan Africa are insufficient with a need for an improved understanding of local epidemiology and the effectiveness of interventions.

Evolutionary Genetics of Mycobacterium tuberculosis and HIV-1: "The Tortoise and the Hare"

The already enormous burden caused by Mycobacterium tuberculosis and Human Immunodeficiency Virus type 1 (HIV-1) alone is aggravated by co-infection. Despite obvious differences in the rate of evolution comparing these two human pathogens, genetic diversity plays an important role in the success of both. The extreme evolutionary dynamics of HIV-1 is in the basis of a robust capacity to evade immune responses, to generate drug-resistance and to diversify the population-level reservoir of M group viral subtypes. Compared to HIV-1 and other retroviruses, M. tuberculosis generates minute levels of genetic diversity within the host. However, emerging whole-genome sequencing data show that the M. tuberculosis complex contains at least nine human-adapted phylogenetic lineages. This level of genetic diversity results in differences in M. tuberculosis interactions with the host immune system, virulence and drug resistance propensity. In co-infected individuals, HIV-1 and M. tuberculosis are likely to co-colonize host cells. However, the evolutionary impact of the interaction between the host, the slowly evolving M. tuberculosis bacteria and the HIV-1 viral "mutant cloud" is poorly understood. These evolutionary dynamics, at the cellular niche of monocytes/macrophages, are also discussed and proposed as a relevant future research topic in the context of single-cell sequencing.

The Intergenerational Impact of a Slow Pandemic: HIV and Children

Human immunodeficiency virus (HIV) has, over the last four decades, infected millions of young women and their children. Interventions developed in parallel with the spread of the virus have been able to reduce rates of vertical transmission from mother to child. The impact of HIV in children can be direct in children living with HIV (CLHIV) and exposed to HIV and uninfected, or indirect through impacts on their parents, caregivers, and family. In 2018, the United Nations joint programme on AIDS (UNAIDS) estimated that 1.7 million children were living with HIV, 160,000 were newly infected with HIV, and 100,000 died from HIV. Improvement in treatment regimens can improve the life chances of children, but adherence to treatment is a problem, especially for adolescents. Injectable long acting treatments, or interventions to improve service delivery and support for adolescents living with HIV may improve treatment success. In addition to failures of HIV prevention and treatment in CLHIV, there are concerns over exposure to the virus and antivirals leading to delayed child development. To improve the wellbeing of children affected by HIV, social support is necessary, but we need to find ways of enhancing the impact of interventions, perhaps through combining them.

Progress and history of the 10th Federation of African Immunological Societies Congress

The 10th Federation of African Immunological Societies (FAIS) Congress, held in Tunisia in November 2017, marked a significant scientific milestone. It enabled scientists from across the continent to promote immunology research and to showcase major achievements made by immunologists throughout Africa. This issue of the Journal of Leukocyte Biology (JLB) features manuscripts from the FAIS Congress. As noted in these papers, research in infectious diseases remains the focus of the African immunology community; however, increasingly noncommunicable diseases-such as autoimmunity, allergy, primary immunodeficiency, cancer and transplantation immunology-are also an emerging priority. This overview gives a brief history of the FAIS meeting, which also commemorated the 25th anniversary of the FAIS. It describes the current activities of the organization, as well as its history and the future opportunities for this Federation.

Planning area-specific prevention and intervention programs for HIV using spatial regression analysis

OBJECTIVE

The study was conducted to inform area-based prevention intervention programs and plan resource allocation to reduce new infections in the District of Columbia (DC), United States of America.

STUDY DESIGN

The analysis used spatial regression to evaluate the spatial heterogeneity of the new HIV rate and its association with sexually transmitted infection repeaters (STIREPs) and socio-economic as well as demographic characteristics. The HIV and STIREP data were obtained from the DC Department of Health surveillance data (2010-2016). Other covariates were obtained from the American Community Survey, 2016.

METHODS

Ordinary least squares (OLS) and geographically weighted regression (GWR) were used to compare global and local relationships. GWR-computed robust results were compared with other spatial regression methods such as spatial lag or spatial error methods.

RESULTS

For the OLS model, age, high school dropouts (NHSD), and the black population had an association with new HIV diagnoses (HIVDV_i). The results from the GWR model demonstrate spatial variations of association of STIREPs; mean age of each block group; and percentage of female population, NHSD, unemployment, and poverty with HIVDV_i. Akaike information criterion (AICc) value for the global model was 2770.99, and R² was 0.54 (54%). The R² and AICc of the GWR model was 0.81 (81%) and 2580.84, respectively, where the latter showed a 0.27 (27%) increase in R² and a decreased AICc.

CONCLUSION

These results will assist in planning HIV prevention and intervention strategies. These results will also be used for targeted testing, planning pre-exposure prophylaxis, and access to health care. The results will help plan resource allocation to community-based providers for prevention intervention programs and fund public health programs such as condom distribution, mobile vans, and youth-based sex education.

Opportunities for Enhanced Strategic Use of Surveys, Medical Records, and Program Data for HIV Surveillance of Key Populations: Scoping Review

BACKGROUND

Normative guidelines from the World Health Organization recommend tracking strategic information indicators among key populations. Monitoring progress in the global response to the HIV epidemic uses indicators put forward by the Joint United Nations Programme on HIV/AIDS. These include the 90-90-90 targets that require a realignment of surveillance data, routinely collected program data, and medical record data, which historically have developed separately.

OBJECTIVE

The aim of this study was to describe current challenges for monitoring HIV-related strategic information indicators among key populations ((men who have sex with men [MSM], people in prisons and other closed settings, people who inject drugs, sex workers, and transgender people) and identify future opportunities to enhance the use of surveillance data, programmatic data, and medical record data to describe the HIV epidemic among key populations and measure the coverage of HIV prevention, care, and treatment programs.

METHODS

To provide a historical perspective, we completed a scoping review of the expansion of HIV surveillance among key populations over the past three decades. To describe current efforts, we conducted a review of the literature to identify published examples of SI indicator estimates among key populations. To describe anticipated challenges and future opportunities to improve measurement of strategic information indicators, particularly from routine program and health data, we consulted participants of the Third Global HIV Surveillance Meeting in Bangkok, where the 2015 World Health Organization strategic information guidelines were launched.

RESULTS

There remains suboptimal alignment of surveillance and programmatic data, as well as routinely collected medical records to facilitate the reporting of the 90-90-90 indicators for HIV among key populations. Studies (n=3) with estimates of all three 90-90-90 indicators rely on cross-sectional survey data. Programmatic data and medical record data continue to be insufficiently robust to provide estimates of the 90-90-90 targets for key populations.

CONCLUSIONS

Current reliance on more active data collection processes, including key population-specific surveys, remains warranted until the quality and validity of passively collected routine program and medical record data for key populations is optimized.

Recent Insights into the HIV/AIDS Pandemic

Etiology, transmission and protection: Transmission of HIV, the causative agent of AIDS, occurs predominantly through bodily fluids. Factors that significantly alter the risk of HIV transmission include male circumcision, condom use, high viral load, and the presence of other sexually transmitted diseases. Pathology/Symptomatology: HIV infects preferentially CD4+ T lymphocytes, and Monocytes. Because of their central role in regulating the immune response, depletion of CD4+ T cells renders the infected individual incapable of adequately responding to microorganisms otherwise inconsequential. Epidemiology, incidence and prevalence: New HIV infections affect predominantly young heterosexual women and homosexual men. While the mortality rates of AIDS related causes have decreased globally in recent years due to the use of highly active antiretroviral therapy (HAART) treatment, a vaccine remains an elusive goal. Treatment and curability: For those afflicted HIV infection remains a serious illness. Nonetheless, the use of advanced therapeutics have transformed a dire scenario into a chronic condition with near average life spans. When to apply those remedies appears to be as important as the remedies themselves. The high rate of HIV replication and the ability to generate variants are central to the viral survival strategy and major barriers to be overcome. Molecular mechanisms of infection: In this review, we assemble new details on the molecular events from the attachment of the virus, to the assembly and release of the viral progeny. Yet, much remains to be learned as understanding of the molecular mechanisms used in viral replication and the measures engaged in the evasion of immune surveillance will be important to develop effective interventions to address the global HIV pandemic.

Nosocomial Transmission of HIV in Africa: What Tribute Is Paid to Contaminated Blood Transfusions and Medical Injections?

We reviewed the published data on the possible impact of medical injections and blood transfusions on the spread of human immunodeficiency virus (HIV) in Africa. We also compared these results to our experience in Rwanda, central Africa. The importance of medical injections in the epidemic of HIV infection seems to differ from one area to another. The excess of injections experienced by HIV seropositive subjects in Zaire could be secondary to the parenteral treatment of early HIV-related illness or to the treatment of sexually transmitted diseases, rather than being the cause of HIV infection, as suggested by Rwandese studies. In contrast, blood transfusions have been shown to represent an important source of nosocomial HIV infection in many African countries. Effective and relatively inexpensive measures to diminish the iatrogenic spread of HIV infection in developing countries are summarized.

HIV-1 subtype B: Traces of a pandemic

Human migration is a major process that shaped the origin and dissemination of HIV. Within HIV-1, subtype B (HIV-1B) is the most disseminated variant and it is assumed to be the causative agent in approximately 11% of all cases of HIV worldwide. Phylogenetic studies have revealed that HIV-1B emerged in Kinshasa (Africa) and was introduced into the Caribbean region via Haiti in or around 1966 by human migration. After localized dispersion, the virus was brought to the United States of America via homosexual/bisexual contact around 1969. Inside USA, the incidence of HIV-1B infection increased exponentially and it became established in the population, affecting not only homosexual individuals but also heterosexual individuals and injecting drug users. Soon after, the virus was disseminated and became established in other regions, including Europe, Asia, Latin America, and Australia. Recent studies suggest that, in addition to this pandemic clade, several lineages have emerged from Haiti and reached other Caribbean and Latin American countries via short-distance dissemination. Different subtype B genetic variants have also been detected in these epidemics. Four genetic variants have been described to date: subtype B', which mainly circulates in Thailand and other Asian countries; a specific variant mainly found in Trinidad and Tobago; the GPGS variant, which is primarily detected in Korea; and the GWGR variant, which is mainly detected in Brazil. This paper reviews the evolution of HIV-1B and its impact on the human population.

Addressing Future Epidemics: Historical Human Rights Lessons from the AIDS Pandemic

INTRODUCTION

The Ebola epidemic in West Africa sparked many ethical and polarizing public health questions on how to adequately control transmission of the virus. These deliberations had and will continue to influence patients, healthcare workers, public perceptions of disease, and governmental responses. Such extensive and potential ramifications warranted an analysis of prior epidemics to sufficiently inform policy makers and prepare them and other authorities for future epidemics. We analyzed how the general public, medical institutions, federal government, and patients themselves responded during the early stages of the AIDS pandemic in two different countries and cultures, the United States and India.

DISCUSSION

Our analysis identified four key findings pertaining to the human rights of patients and healthcare workers and to the crucial roles of the government and medical community. The first demands that authoritative officials acknowledge the presence of high-risk behaviors and properly educate the public without stigmatizing groups of individuals. For this task, the medical community and federal government must form and display to the public a respectful and collaborative partnership towards battling the epidemic. These two synergistic endeavors will then allow appropriate officials to implement effective, yet civil, interventions for limiting transmission. Finally, the same officials must ensure that their interventions maintain the human rights of high-risk populations and of healthcare workers.

CONCLUSIONS

Applying these findings to future epidemics of infectious diseases can aid policy makers in navigating complicated ethical and public health questions, and help prevent them from repeating past mistakes in handling epidemics.

Management of severe non-TB bacterial infection in HIV-infected adults

Despite widespread antiretroviral therapy use, severe bacterial infections (SBI) in HIV-infected adults continue to cause significant morbidity and mortality globally. Four main pathogens account for the majority of documented SBI: Streptococcus pneumoniae, non-typhoidal strains of Salmonella enterica, Escherichia coli and Staphylococcus aureus. The epidemiology of SBI is dynamic, both in developing countries where, despite dramatic successes in antiretroviral therapy, coverage is far from complete, and in settings in both resource-poor and resource-rich countries where antiretroviral therapy failure is becoming increasingly common. Throughout the world, this complexity is further compounded by rapidly emerging antimicrobial resistance, making management of SBI very challenging in these vulnerable patients. We review the causes and treatment of SBI in HIV-infected people and discuss future developments in this field.

The development of a localised HIV epidemic and the associated excess mortality burden in a rural area of South Africa

The human immunodeficiency virus (HIV) epidemic in South Africa rapidly developed into a major pandemic. Here we analyse the development of the epidemic in a rural area of the country. The data used were collected between 1992 and 2013 in a longitudinal population survey, the Agincourt Health and Demographic Surveillance Study, in the northeast of the country. Throughout the period of study mortality rates were similar in all villages, suggesting that there were multiple index cases evenly spread geographically. These were likely to have been returning migrant workers. For those aged below 39 years the HIV mortality rate was higher for women, above this age it was higher for men. This indicates the protective effect of greater access to HIV testing and treatment among older women. The recent convergence of mortality rates for Mozambicans and South Africans indicates that the former refugee population are being assimilated into the host community. More than 60% of the deaths occurring in this community between 1992 and 2013 could be attributed directly or indirectly to HIV. Recently there has been an increasing level of non-HIV mortality which has important implications for local healthcare provision. This study demonstrates how evidence from longitudinal analyses can support healthcare planning.

Loss of Multicellular Behavior in Epidemic African Nontyphoidal Salmonella enterica Serovar Typhimurium ST313 Strain D23580

Nontyphoidal Salmonella enterica serovar Typhimurium is a frequent cause of bloodstream infections in children and HIV-infected adults in sub-Saharan Africa. Most isolates from African patients with bacteremia belong to a single sequence type, ST313, which is genetically distinct from gastroenteritis-associated ST19 strains, such as 14028s and SL1344. Some studies suggest that the rapid spread of ST313 across sub-Saharan Africa has been facilitated by anthroponotic (person-to-person) transmission, eliminating the need for Salmonella survival outside the host. While these studies have not ruled out zoonotic or other means of transmission, the anthroponotic hypothesis is supported by evidence of extensive genomic decay, a hallmark of host adaptation, in the sequenced ST313 strain D23580. We have identified and demonstrated 2 loss-of-function mutations in D23580, not present in the ST19 strain 14028s, that impair multicellular stress resistance associated with survival outside the host. These mutations result in inactivation of the KatE stationary-phase catalase that protects high-density bacterial communities from oxidative stress and the BcsG cellulose biosynthetic enzyme required for the RDAR (red, dry, and rough) colonial phenotype. However, we found that like 14028s, D23580 is able to elicit an acute inflammatory response and cause enteritis in mice and rhesus macaque monkeys. Collectively, these observations suggest that African S. Typhimurium ST313 strain D23580 is becoming adapted to an anthroponotic mode of transmission while retaining the ability to infect and cause enteritis in multiple host species.

IMPORTANCE

The last 3 decades have witnessed an epidemic of invasive nontyphoidal Salmonella infections in sub-Saharan Africa. Genomic analysis and clinical observations suggest that the Salmonella strains responsible for these infections are evolving to become more typhoid-like with regard to patterns of transmission and virulence. This study shows that a prototypical African nontyphoidal Salmonella strain has lost traits required for environmental stress resistance, consistent with an adaptation to a human-to-human mode of transmission. However, in contrast to predictions, the strain remains capable of causing acute inflammation in the mammalian intestine. This suggests that the systemic clinical presentation of invasive nontyphoidal Salmonella infections in Africa reflects the immune status of infected hosts rather than intrinsic differences in the virulence of African Salmonella strains. Our study provides important new insights into the evolution of host adaptation in bacterial pathogens.

Is utilization of health services for HIV patients equal by socioeconomic status? Evidence from the Basque country

Introduction

Access to ART and health services is guaranteed under universal coverage to improve life expectancy and quality of life for HIV patients. However, it remains unknown whether patients of different socioeconomic background equally use different types of health services.

Methods

We use one-year (2010–2011) data on individual healthcare utilization and expenditures for the total population (N = 2262698) of the Basque Country. We observe the prevalence of HIV and use OLS regressions to estimate the impact on health utilization of demographic, socioeconomic characteristics, and health status in such patients.

Results

HIV prevalence per 1000 individuals is greater the lower the socioeconomic status (0.784 for highest; 2.135 for lowest), for males (1.616) versus females (0.729), and for middle-age groups (26–45 and 46–65). Health expenditures are 11826€ greater for HIV patients than for others, but with differences by socioeconomic group derived from a different mix of services utilization (total cost of 13058€ for poorest, 14960€ for richest). Controlling for health status and demographic variables, poor HIV patients consume more on pharmaceuticals; rich in specialists and hospital care. Therefore, there is inequity in health services utilization by socioeconomic groups.

Conclusions

Equity in health provision for HIV patients represents a challenge even if access to treatment is guaranteed. Lack of information in poorer individuals might lead to under-provision while richer individuals might demand over-provision. We recommend establishing accurate clinical guidelines with the appropriate mix of health provision by validated need for all socioeconomic groups; promoting educational programs so that patients demand the appropriate mix of services, and stimulating integrated care for HIV patients with multiple chronic conditions.

HIV epidemiology. The early spread and epidemic ignition of HIV-1 in human populations

Thirty years after the discovery of HIV-1, the early transmission, dissemination, and establishment of the virus in human populations remain unclear. Using statistical approaches applied to HIV-1 sequence data from central Africa, we show that from the 1920s Kinshasa (in what is now the Democratic Republic of Congo) was the focus of early transmission and the source of pre-1960 pandemic viruses elsewhere. Location and dating estimates were validated using the earliest HIV-1 archival sample, also from Kinshasa. The epidemic histories of HIV-1 group M and nonpandemic group O were similar until ~1960, after which group M underwent an epidemiological transition and outpaced regional population growth. Our results reconstruct the early dynamics of HIV-1 and emphasize the role of social changes and transport networks in the establishment of this virus in human populations.

AIDS in Africa: distinguishing fact and fiction

The data widely purporting to show the existence and heterosexual transmission in Africa of a new syndrome caused by a retrovirus which induces immune deficiency are critically evaluated. It is concluded that both acquired immune deficiency (AID) and the symptoms and diseases which constitute the clinical syndrome (S) are of long standing in Africa, affect both sexes equally and are caused directly and indirectly by factors other than human immunodeficiency virus (HIV). Seropositivity to HIV in Africans usually represents no more than cross-reactivity caused by an abundance of antibodies induced by the numerous infectious and parasitic diseases which are endemic in Africa. The apparently high prevalence of 'AIDS' and 'HIV' seropositives is therefore not surprising and is not proof of heterosexual transmission of either HIV or AIDS.

Reconstructing the timing and dispersion routes of HIV-1 subtype B epidemics in the Caribbean and Central America: a phylogenetic story

The Caribbean and Central America are among the regions with highest HIV-1B prevalence worldwide. Despite of this high virus burden, little is known about the timing and the migration patterns of HIV-1B in these regions. Migration is one of the major processes shaping the genetic structure of virus populations. Thus, reconstruction of epidemiological network may contribute to understand HIV-1B evolution and reduce virus prevalence. We have investigated the spatio-temporal dynamics of the HIV-1B epidemic in The Caribbean and Central America using 1,610 HIV-1B partial pol sequences from 13 Caribbean and 5 Central American countries. Timing of HIV-1B introduction and virus evolutionary rates, as well as the spatial genetic structure of the HIV-1B populations and the virus migration patterns were inferred. Results revealed that in The Caribbean and Central America most of the HIV-1B variability was generated since the 80 s. At odds with previous data suggesting that Haiti was the origin of the epidemic in The Caribbean, our reconstruction indicated that the virus could have been disseminated from Puerto Rico and Antigua. These two countries connected two distinguishable migration areas corresponding to the (mainly Spanish-colonized) Easter and (mainly British-colonized) Western islands, which indicates that virus migration patterns are determined by geographical barriers and by the movement of human populations among culturally related countries. Similar factors shaped the migration of HIV-1B in Central America. The HIV-1B population was significantly structured according to the country of origin, and the genetic diversity in each country was associated with the virus prevalence in both regions, which suggests that virus populations evolve mainly through genetic drift. Thus, our work contributes to the understanding of HIV-1B evolution and dispersion pattern in the Americas, and its relationship with the geography of the area and the movements of human populations.

Antiretrovirals and safer conception for HIV-serodiscordant couples

PURPOSE OF REVIEW

Many men and women living with HIV and their uninfected partners attempt to conceive children. HIV-prevention science can be applied to reduce sexual transmission risk while respecting couples' reproductive goals. Here we discuss antiretrovirals as prevention in the context of safer conception for HIV-serodiscordant couples.

RECENT FINDINGS

Antiretroviral therapy (ART) for the infected partner and pre-exposure prophylaxis (PrEP) for the uninfected partner reduce the risk of heterosexual HIV transmission. Several demonstration projects suggest the feasibility and acceptability of antiretroviral (ARV)s as periconception HIV-prevention for HIV-serodiscordant couples. The application of ARVs to periconception risk reduction may be limited by adherence.

SUMMARY

For male-infected (M+F-) couples who cannot access sperm processing and female-infected (F+M-) couples unwilling to carry out insemination without intercourse, ART for the infected partner, PrEP for the uninfected partner, combined with treatment for sexually transmitted infections, sex limited to peak fertility, and medical male circumcision (for F+M couples) provide excellent, well tolerated options for reducing the risk of periconception HIV sexual transmission.

Sexual behavior and AIDS in sociocultural perspective

AIDS, its cause, effect, and possible cure, has become a complex sociopsychological issue with ramifications extending far beyond the purely medical sphere. Spreading rapidly, with a higher incidence rate recorded among young people, the disease transcended the biomedical sphere, presenting sociocultural and psychological ramifications that go beyond its physical impact. With a higher incidence rate among male homosexuals, the epidemic raises morally sensitive questions which further confuse an already clouded picture. Current knowledge on the sexual transmission of AIDS and the role of male homosexuality demonstrates the need for more serious research into the various social and cultural aspects of homosexuality itself. To this end, medical anthropology may provide important information to those dealing with educational and preventive programs for the general population, as well as those in high risk groups for acquiring the disease.

Anal intercourse and HIV risk among low-income heterosexual women: findings from Chicago HIV behavioral surveillance

Background:

Anal intercourse (AI) is a highly efficient route for HIV transmission and has not been well elucidated among heterosexual (HET) women. Heterosexual women living in impoverished urban areas in the US are at increased risk for HIV acquisition. We aim to describe rates of AI and characteristics associated with AI among heterosexual women at increased risk for HIV acquisition living in Chicago.

Methods:

The Chicago Department of Public Health conducted a survey of HET during 2007 as part of the National HIV Behavioral Surveillance System. Venue-based, time-location sampling was used to select participants from venues in high-risk areas (census tracts with concurrently high rates of heterosexual AIDS and household poverty). Eligible participants were interviewed anonymously and offered a HIV test.

Results:

In total, 407 heterosexual women were interviewed. Seventy-one (17%) women reported having AI in the past 12 months, with 61 of the 71 (86%) reporting unprotected AI. In multivariate analysis, women who engaged in AI were more than three times as likely to have three or more sex partners in the past 12 months (OR=3.27, 95% CI 1.53-6.99). AI was also independently associated with STI diagnosis in the past 12 months (2.13, 95% CI 1.06-4.26), and having sexual intercourse for the first time before the age of 15 years (2.23, 95% CI 1.28-3.89).

Conclusion:

AI was associated with multiple high risk behaviors including a greater number of sexual partners, STI diagnosis, and earlier age at first sex. The combination of risk factors found to be associated with AI call for new HIV prevention services tailored to the needs of women and young girls living in poverty.

Invasive non-typhoidal salmonella disease: an emerging and neglected tropical disease in Africa

Invasive strains of non-typhoidal salmonellae have emerged as a prominent cause of bloodstream infection in African adults and children, with an associated case fatality of 20-25%. The clinical presentation of invasive non-typhoidal salmonella disease in Africa is diverse: fever, hepatosplenomegaly, and respiratory symptoms are common, and features of enterocolitis are often absent. The most important risk factors are HIV infection in adults, and malaria, HIV, and malnutrition in children. A distinct genotype of Salmonella enterica var Typhimurium, ST313, has emerged as a new pathogenic clade in sub-Saharan Africa, and might have adapted to cause invasive disease in human beings. Multidrug-resistant ST313 has caused epidemics in several African countries, and has driven the use of expensive antimicrobial drugs in the poorest health services in the world. Studies of systemic cellular and humoral immune responses in adults infected with HIV have revealed key host immune defects contributing to invasive non-typhoidal salmonella disease. This emerging pathogen might therefore have adapted to occupy an ecological and immunological niche provided by HIV, malaria, and malnutrition in Africa. A good understanding of the epidemiology of this neglected disease will open new avenues for development and implementation of vaccine and public health strategies to prevent infections and interrupt transmission.

The evolving epidemiology of HIV/AIDS

Following its recognition in 1981, the HIV/AIDS epidemic has evolved to become the greatest challenge in global health, with some 34 million persons living with HIV worldwide. Early epidemiologic studies identified the major transmission routes of the virus before it was discovered, and enabled the implementation of prevention strategies. Although the first identified cases were in MSM in the United States and western Europe, the greatest impact of the epidemic has been in sub-Saharan Africa, where most of the transmission occurs between heterosexuals. Nine countries in southern Africa account for less than 2% of the world's population but now they represent about one third of global HIV infections. Where broadly implemented, HIV screening of donated blood and antiretroviral treatment (ART) of pregnant women have been highly effective in preventing transfusion-associated and perinatally acquired HIV, respectively. Access to sterile equipment has also been a successful intervention for injection drug users. Prevention of sexual transmission has been more difficult. Perhaps the greatest challenge in terms of prevention has been in the global community of MSM in which HIV remains endemic at high prevalence. The most promising interventions are male circumcision for prevention of female-to-male transmission and use of ART to reduce infectiousness, but the extent to which these interventions can be brought to scale will determine their population-level impact.

Prevention of sexual transmission of HIV: real results, science progressing, societies remaining behind

HIV spread has reached a turning point following decades of increasing and sustained incidence. An effective vaccine has not been developed, but critical breakthroughs with prevention based on antiretroviral treatment are promising. The new prevention technologies will have to be combined with condoms and incorporated into the mixes of combination prevention approaches that are tailored to the local epidemic and context. To address the implementation gap, more political will and leadership will be needed to overcome the socio-cultural, legal or religious barriers to prevention. We have learned that the generation of demand for HIV prevention is not easy, as for health promotion in general. Despite optimism about treatment as prevention, many western countries are facing an increase in new HIV cases, and HIV is no longer a collective concern. If we manage to find common ground on combination prevention, customize approaches to people's needs and exercise technical and political leadership, our decade may see the beginning of the end of the epidemic.

The HIV-1 epidemic: low- to middle-income countries

Low- to middle-income countries bear the overwhelming burden of the human immunodeficiency virus type 1 (HIV-1) epidemic in terms of the numbers of their citizens living with HIV/AIDS (acquired immunodeficiency syndrome), the high degrees of viral diversity often involving multiple HIV-1 clades circulating within their populations, and the social and economic factors that compromise current control measures. Distinct epidemics have emerged in different geographical areas. These epidemics differ in their severity, the population groups they affect, their associated risk behaviors, and the viral strains that drive them. In addition to inflicting great human cost, the high burden of HIV infection has a major impact on the social and economic development of many low- to middle-income countries. Furthermore, the high degrees of viral diversity associated with multiclade HIV epidemics impacts viral diagnosis and pathogenicity and treatment and poses daunting challenges for effective vaccine development.

Prevention of mother to child transmission of human immunodeficiency virus: the nigerian perspective

Despite the proven effectiveness of the prevention of mother to child transmission (PMTCT) of human immunodeficiency virus (HIV) program, Nigeria currently has the highest burden of vertical transmission of HIV in the world due to poor coverage of the PMTCT program partly as a result of poor knowledge of PMTCT interventions amongst healthcare providers in the country. This paper aims at making information on PMTCT interventions more readily available to healthcare providers in developing countries. The internet was searched using Google and Google scholar. In addition, relevant electronic journals from the Universities library including PubMed and Scirus, Medline, Cochrane library, and World Health Organization (WHO)'s Hinari were used. There was paucity of published work on PMCT from Nigeria. Most of the information concerning PMCT in Nigeria was obtained from technical reports from the Federal Ministry of Health and WHO. It is expected that this article will help in improving healthcare providers' knowledge of PMTCT interventions and thus help in the urgently needed rapid scale-up of PMTCT services in Nigeria.

The evolving HIV/AIDS response and the urgent tasks ahead

AIDS continues to outpace the science, financing, prevention, and treatment efforts of the past quarter-century. There have been different epochs along the evolutionary timeline of the global AIDS response, from the discovery of HIV to the threat posed by the current economic crisis. This timeline serves as a reference to how we have arrived where we are today, in the hope that understanding our past will help us set the course for a more efficient and effective future response.

Antihistamines are superior to topical steroids in managing human immunodeficiency virus (HIV)-associated papular pruritic eruption

Papular pruritic eruption (PPE) is a frequent HIV-comorbidity in tropical countries. Because of constant itching and social stigma, effective treatment is highly valued. In our HIV cohort in rural Tanzania with 12% prevalence of PPE, we have retrospectively analyzed responses to available treatments. Oral promethazine improved itching (P < 0.0058) and clinical scores (P < 0.032) significantly more than topical steroids. Disease activity did not correlate with CD4+ and CD8+ T cell counts and was independent of anti-retroviral medication. Therefore, oral antihistamines are an effective first-line treatment for PPE.

Behavioral mechanisms in HIV epidemiology and prevention: past, present, and future roles

In the 1980s, behavioral variations across geographically and socially defined populations were the central focus of AIDS research, and behavior change was seen as the primary means of controlling HIV epidemics. Today, biological mechanisms--especially other sexually transmitted infections, antiretroviral therapy, and male circumcision--predominate in HIV epidemiology and prevention. We describe several reasons for this shift in emphasis. Although the shift is understandable, we argue for a sustained focus on behavioral mechanisms in HIV research in order to realize the theoretical promise of interventions targeting the biological aspects of HIV risk. We also provide evidence to suggest that large reductions in HIV prevalence may be accomplished by small changes in behavior. Moreover, we contend that behavioral mechanisms will find their proper place in HIV epidemiology and prevention only when investigators adopt a conceptual model that treats prevalence as a determinant as well as an outcome of behavior and that explicitly recognizes the dynamic interdependence between behavior and other epidemiological and demographic parameters.

Sexualised space, sexual networking & the emergence of AIDS in Rakai, Uganda

This paper argues that the outbreak of the epidemic of AIDS in Rakai, Uganda, in the early 1980s was a consequence of economic change, leading to the erosion of conventional cultural checks on juvenile, female and male sexuality and the emergence and growth of sexualised spaces and sexual networking in a few remote rural hubs of economic activity which exhibited a different sexual culture from the surrounding countryside. The trading hubs developed dense local and regional sexual networks which enabled HIV to spread quickly among the "risk groups" and local people of the busiest trading towns and villages. The high degree of sexual mixing in these hubs opened up new routes for HIV to infect the general population. This paper, which shows the importance of understanding the role of the aggravated economic disparities and changing sexual culture in the onset and spread of the HIV and AIDS epidemic in Rakai, Uganda, is primarily based on in-depth interviews and focus group discussions and on the analysis of newspapers, unofficial and official documents and academic studies.

Men who have sex with men and HIV/AIDS in sub-Saharan Africa

Globally, men who have sex with men (MSM) continue to bear a high burden of HIV infection. In sub-Saharan Africa, same-sex behaviours have been largely neglected by HIV research up to now. The results from recent studies, however, indicate the widespread existence of MSM groups across Africa, and high rates of HIV infection, HIV risk behaviour, and evidence of behavioural links between MSM and heterosexual networks have been reported. Yet most African MSM have no safe access to relevant HIV/AIDS information and services, and many African states have not begun to recognise or address the needs of these men in the context of national HIV/AIDS prevention and control programmes. The HIV/AIDS community now has considerable challenges in clarifying and addressing the needs of MSM in sub-Saharan Africa; homosexuality is illegal in most countries, and political and social hostility are endemic. An effective response to HIV/AIDS requires improved strategic information about all risk groups, including MSM. The belated response to MSM with HIV infection needs rapid and sustained national and international commitment to the development of appropriate interventions and action to reduce structural and social barriers to make these accessible.

Denialism undermines AIDS prevention in sub-Saharan Africa

Some denialists, widely reviled, contend that HIV does not cause AIDS. Other denialists, widely respected, contend that HIV transmits so poorly through trace blood exposures that iatrogenic infections are rare. This second group of denialists has had a corrosive effect on public health and HIV programmes in sub-Saharan Africa. Guided by this second group of denialists, no African government has investigated unexplained HIV infections. Denialists have withheld and ignored research findings showing that non-sexual risks account for substantial proportions of HIV infections in Africa. Denialists have promoted invasive procedures for HIV prevention in Africa--injections for sexually transmitted infections, and adult male circumcision--without addressing unreliable sterilization of reused instruments. By denying that health care causes more than rare infections, denialists blame (stigmatize) HIV-positive African adults for causing their own infections through sexual behaviour. Denialism must be overcome to ensure safe health care and to combat HIV-related stigma in Africa.

Salmonella infections in immunocompromised adults

Clinical syndromes caused by Salmonella infection in humans are divided into typhoid fever, caused by Salmonella typhi and Salmonella paratyphi, and a range of clinical syndromes, including diarrhoeal disease, caused by a large number of non-typhoidal salmonella serovars (NTS). Typhoid is a human-restricted and highly adapted invasive disease, but shows little association with immunocompromise. In contrast, NTS have a broad vertebrate host range, epidemiology that often involves food animals, and have a dramatically more severe and invasive presentation in immunocompromised adults, in particular in the context of HIV. Immunocompromise among adults, including underlying severe or progressive disease, chronic granulomatous disease, defects or blockade of specific cytokines (particularly IL-12/IL-23/IL-17 and TNF), and HIV, is associated with suppurative foci and with primary bacteraemic disease, which may be recurrent. These patients have markedly increased mortality. Worldwide, invasive recurrent NTS bacteraemia associated with advanced HIV disease is a huge problem, and the epidemiology in this context may be more human-restricted than in other settings. This review will describe the presentation and pathogenesis of NTS in different categories of immunocompromised adults, contrasted to typhoid fever.

Special anniversary review: twenty-five years of human immunodeficiency virus research: successes and challenges

During 25 years of research since HIV-1 was first identified in Paris, there have been great advances in our understanding of the virus and of the immune system. Practical advances include the early development of diagnostic tests of infection that made blood donation safe, and since 1996, combination anti-retroviral therapy that has great reduced incidence of AIDS in HIV-infected people who have access to the drugs. HIV prevention through behavioural change has been successful, and we do not yet have any safe and efficacious microbicides or vaccines.

The emergence of HIV/AIDS in the Americas and beyond

HIV-1 group M subtype B was the first HIV discovered and is the predominant variant of AIDS virus in most countries outside of sub-Saharan Africa. However, the circumstances of its origin and emergence remain unresolved. Here we propose a geographic sequence and time line for the origin of subtype B and the emergence of pandemic HIV/AIDS out of Africa. Using HIV-1 gene sequences recovered from archival samples from some of the earliest known Haitian AIDS patients, we find that subtype B likely moved from Africa to Haiti in or around 1966 (1962-1970) and then spread there for some years before successfully dispersing elsewhere. A "pandemic" clade, encompassing the vast majority of non-Haitian subtype B infections in the United States and elsewhere around the world, subsequently emerged after a single migration of the virus out of Haiti in or around 1969 (1966-1972). Haiti appears to have the oldest HIV/AIDS epidemic outside sub-Saharan Africa and the most genetically diverse subtype B epidemic, which might present challenges for HIV-1 vaccine design and testing. The emergence of the pandemic variant of subtype B was an important turning point in the history of AIDS, but its spread was likely driven by ecological rather than evolutionary factors. Our results suggest that HIV-1 circulated cryptically in the United States for approximately 12 years before the recognition of AIDS in 1981.

Tuberculosis and HIV Infection: The Global Setting

Tuberculosis (TB) and human immunodeficiency virus (HIV) infection make each other's control significantly more difficult. Coordination in addressing this "cursed duet" is insufficient at both global and national levels. However, global policy for TB/HIV coordination has been set, and there is consensus around this policy from both the TB and HIV control communities. The policy aims to provide all necessary care for the prevention and management of HIV-associated TB, but its implementation is hindered by real technical difficulties and shortages of resources. All major global-level institutions involved in HIV care and prevention must include TB control as part of their corporate policy. Country-level decision makers need to work together to expand both TB and HIV services, and civil society and community representatives need to hold those responsible accountable for their delivery. The TB and HIV communities should join forces to address the health-sector weaknesses that confront them both.

Pruritic Papular Eruption in HIV

Pruritic papular eruption (PPE) is characterized chronic pruritus and symmetric papular eruptions on the trunk and extremities with the absence of other definable causes of itching in an HIV-infected patient. PPE seems to be much more prevalent in less developed regions of the world. The etiology of this distressing condition is unclear, although an inappropriate response to an exogenous agent, such as arthropod bites, may underlie the pathogenesis. Identifying PPE's association with the immune dysregulation of HIV and distinguishing this condition from other pruritic disorders found in HIV-infected patients is important for optimal management.

Sexually transmitted infections and HIV among travellers: A review

Sexually transmitted infections are often acquired during travel. Infections are most often seen in young adults, travelling without a regular partner and among those who have higher numbers of partners while at home. Alcohol and recreational drug use may increase risk. The risks are highest from having unprotected sex with local partners in developing countries where the prevalence of infection can be many times higher than at home. The risks of acquiring HIV are highest in Africa, followed by South Asia. Special precautions are required by those going to work in health-care settings in high HIV prevalence countries. Travellers may benefit from advice about safer sex, condom use, emergency contraception and vaccination against hepatitis B. In special circumstances a starter pack for HIV post-exposure prophylaxis should be considered. Following return travellers should consider attending specialist services for a screen for sexually transmitted infections and HIV if they are concerned about exposure whilst travelling. A number of reports suggest that travel clinics need to pay more attention to the sexual health of travellers.