The sero-epidemiology of Kaposi's sarcoma-associated herpesvirus (KSHV/HHV-8) in adults with cancer in Uganda

Clinical and Demographic Factors Associated With Kaposi Sarcoma-Associated Herpesvirus Shedding in Saliva or Cervical Secretions in a Cohort of Tanzanian Women

Background

Reasons for the high prevalence of Kaposi sarcoma-associated herpesvirus (KSHV) in sub-Saharan Africa, and risk factors leading to viral reactivation and shedding, remain largely undefined. Preliminary studies have suggested that schistosome infection, which has been associated with impaired viral control, is associated with KSHV. In this study we sought to determine the relationship between active Schistosoma mansoni or Schistosoma haematobium infection and KSHV shedding.

Methods

We quantified KSHV DNA in saliva and cervical swabs from 2 cohorts of women living in northwestern Tanzanian communities endemic for S mansoni or S haematobium by real-time polymerase chain reaction. χ2 and Fisher exact tests were used to determine differences in clinical and demographic factors between those who were and were not shedding KSHV.

Results

Among 139 total women, 44.6% were KSHV seropositive. Six percent of those with S mansoni and 17.1% of those with S haematobium were actively shedding KSHV in saliva and none in cervical samples. Women from the S mansoni cohort who were shedding virus reported infertility more frequently (80% vs 19.5%, P = .009). There was no difference in frequency of KSHV salivary shedding between schistosome-infected and -uninfected women.

Conclusions

In an area with high KSHV seroprevalence and endemic schistosome infections, we provide the first report with data demonstrating no association between schistosome infection and salivary or cervical herpesvirus shedding. KSHV salivary shedding was associated with infertility, a known effect of another herpesvirus, human herpesvirus 6.

Integration of incomplete multi-omics data using Knowledge Distillation and Supervised Variational Autoencoders for disease progression prediction

OBJECTIVE

The rapid advancement of high-throughput technologies in the biomedical field has resulted in the accumulation of diverse omics data types, such as mRNA expression, DNA methylation, and microRNA expression, for studying various diseases. Integrating these multi-omics datasets enables a comprehensive understanding of the molecular basis of cancer and facilitates accurate prediction of disease progression.

METHODS

However, conventional approaches face challenges due to the dimensionality curse problem. This paper introduces a novel framework called Knowledge Distillation and Supervised Variational AutoEncoders utilizing View Correlation Discovery Network (KD-SVAE-VCDN) to address the integration of high-dimensional multi-omics data with limited common samples. Through our experimental evaluation, we demonstrate that the proposed KD-SVAE-VCDN architecture accurately predicts the progression of breast and kidney carcinoma by effectively classifying patients as long- or short-term survivors. Furthermore, our approach outperforms other state-of-the-art multi-omics integration models.

RESULTS

Our findings highlight the efficacy of the KD-SVAE-VCDN architecture in predicting the disease progression of breast and kidney carcinoma. By enabling the classification of patients based on survival outcomes, our model contributes to personalized and targeted treatments. The favorable performance of our approach in comparison to several existing models suggests its potential to contribute to the advancement of cancer understanding and management.

CONCLUSION

The development of a robust predictive model capable of accurately forecasting disease progression at the time of diagnosis holds immense promise for advancing personalized medicine. By leveraging multi-omics data integration, our proposed KD-SVAE-VCDN framework offers an effective solution to this challenge, paving the way for more precise and tailored treatment strategies for patients with different types of cancer.

Soluble biomarkers of HIV-1-related systemic immune activation are associated with high plasma levels of growth factors implicated in the pathogenesis of Kaposi sarcoma in adults

Background

Human Herpesvirus-8 (HHV-8) is the etiologic agent of Kaposi's sarcoma (KS), a multicentric angio-proliferative cancer commonly associated with Human Immunodeficiency Virus (HIV) infection. KS pathogenesis is a multifactorial condition hinged on immune dysfunction yet the mechanisms underlying the risk of developing KS in HHV-8 seropositive adults remains unclear. Here we explored whether soluble markers of HIV-1-related systemic immune activation (SIA) and angiogenesis (VEGF and FGF acidic) are involved in the pathogenesis of KS in adults with HHV8.

Methodology

Blood samples from 99 HIV-1 infected and 60 HIV-1 uninfected adults were collected in Yaoundé, Cameroon. CD3+/CD4+ T cell counts and HIV-1 plasma viral load were determined using the Pima Analyzer and the RT-PCR technique, respectively. Plasma levels of SIA biomarkers (sCD163, sCD25/IL-2Rα, and sCD40/TNFRSF5) and biomarkers of progression to KS (VEGF and FGF acidic) were measured using the Luminex assay. Seropositivity (IgG) for HHV-8 was determined using the ELISA method.

Results

Overall, 20.2% (20/99) of HIV-1 infected and 20% (12/60) of HIV-1 uninfected participants were seropositive for HHV8. Levels of sCD163, sCD25/IL-2Rα, sCD40/TNFRSF5, and FGF acidic were higher in the HIV-1 and HHV8 co-infection groups compared to the HIV-1 and HHV8 uninfected groups (all P <0.05). In addition, Higher plasma levels of VEGF correlated with sCD163 (rs = 0.58, P =0.0067) and sCD40/TNFRSF5 (rs = 0.59, P = 0.0064), while FGF acidic levels correlated with sCD40/TNFRSF5 (rs = 0.51, P = 0.022) in co-infected. In HIV-1 mono-infected donors, VEGF and FGF acidic levels correlated with sCD163 (rs =0.25, P = 0.03 and rs = 0.30, P = 0.006 respectively), sCD25/IL-2Rα (rs = 0.5, P <0.0001 and rs = 0.55, P <0.0001 respectively) and sCD40/TNFRSF5 (rs = 0.7, P <0.0001 and rs = 0.59, P <0.0001 respectively) and even in patients that were virally suppressed sCD25/IL-2Rα (rs = 0.39, P = 0.012 and rs = 0.53, P = 0.0004 respectively) and sCD40/TNFRSF5 (rs = 0.81, P <0.0001 and rs = 0.44, P = 0.0045 respectively).

Conclusion

Our findings suggest that although the development of KS in PLWH is multifactorial, HIV-associated SIA might be among the key drivers in coinfections with HHV8 and is independent of the patients' viremic status.

The Impact of Co-Infections for Human Gammaherpesvirus Infection and Associated Pathologies

The two oncogenic human gammaherpesviruses Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV) cause significant disease burden, particularly in immunosuppressed individuals. Both viruses display latent and lytic phases of their life cycle with different outcomes for their associated pathologies. The high prevalence of infectious diseases in Sub-Saharan Africa (SSA), particularly HIV/AIDS, tuberculosis, malaria, and more recently, COVID-19, as well as their associated inflammatory responses, could potentially impact either virus' infectious course. However, acute or lytically active EBV and/or KSHV infections often present with symptoms mimicking these predominant diseases leading to misdiagnosis or underdiagnosis of oncogenic herpesvirus-associated pathologies. EBV and/or KSHV infections are generally acquired early in life and remain latent until lytic reactivation is triggered by various stimuli. This review summarizes known associations between infectious agents prevalent in SSA and underlying EBV and/or KSHV infection. While presenting an overview of both viruses' biphasic life cycles, this review aims to highlight the importance of co-infections in the correct identification of risk factors for and diagnoses of EBV- and/or KSHV-associated pathologies, particularly in SSA, where both oncogenic herpesviruses as well as other infectious agents are highly pervasive and can lead to substantial morbidity and mortality.

Distinct genetic architectures and environmental factors associate with host response to the γ2-herpesvirus infections

Kaposi's sarcoma-associated herpesvirus (KSHV) and Epstein-Barr Virus (EBV) establish life-long infections and are associated with malignancies. Striking geographic variation in incidence and the fact that virus alone is insufficient to cause disease, suggests other co-factors are involved. Here we present epidemiological analysis and genome-wide association study (GWAS) in 4365 individuals from an African population cohort, to assess the influence of host genetic and non-genetic factors on virus antibody responses. EBV/KSHV co-infection (OR = 5.71(1.58-7.12)), HIV positivity (OR = 2.22(1.32-3.73)) and living in a more rural area (OR = 1.38(1.01-1.89)) are strongly associated with immunogenicity. GWAS reveals associations with KSHV antibody response in the HLA-B/C region (p = 6.64 × 10-09). For EBV, associations are identified for VCA (rs71542439, p = 1.15 × 10-12). Human leucocyte antigen (HLA) and trans-ancestry fine-mapping substantiate that distinct variants in HLA-DQA1 (p = 5.24 × 10-44) are driving associations for EBNA-1 in Africa. This study highlights complex interactions between KSHV and EBV, in addition to distinct genetic architectures resulting in important differences in pathogenesis and transmission.

Kaposi Sarcoma-Associated Herpesvirus in a Rural Ugandan Cohort, 1992-2008

Background

The prevalence and titers of antibodies against Kaposi sarcoma-associated herpesvirus (KSHV) in rural Africa are not completely understood, nor are their trends over time in populations in which human immunodeficiency virus (HIV) is also endemic. We examined prevalence, titers, temporal trends, and determinants of anti-KSHV antibodies in each of 3 time periods (1990-1991, 1999-2000, and 2007-2008) within a long-standing, rural population-based cohort in southwestern Uganda.

Methods

For each period, we measured antibodies to the K8.1 and ORF73 KSHV antigens in approximately 3000 people of all ages (1:1 sex ratio).

Results

In all periods, KSHV prevalence increased rapidly through childhood to approximately 90% by age 15 years, plateauing at approximately 95% thereafter. Similarly, antibody titers, particularly against the lytic antigen K8.1, were among the highest seen and increased significantly with age, suggesting sustained viral replication in this population. Male sex was also independently associated with higher prevalence, whereas HIV coinfection was not. A modest reduction in prevalence among children was noted in the most recent period.

Conclusions

KSHV seroprevalence and antibodies titers in this rural Ugandan population are the highest yet reported, perhaps reflecting frequent viral reactivation and persistently elevated transmission.

Genome-Wide Sequence Analysis of Kaposi Sarcoma-Associated Herpesvirus Shows Diversification Driven by Recombination

Background

Kaposi sarcoma-associated herpesvirus (KSHV) establishes lifelong infection in the human host and has been associated with a variety of malignancies. KSHV displays striking geographic variation in prevalence, which is highest in sub-Saharan Africa. The current KSHV genome sequences available are all tumor cell line-derived or primary tumor-associated viruses, which have provided valuable insights into KSHV genetic diversity.

Methods

Here, we sequenced 45 KSHV genomes from a Ugandan population cohort in which KSHV is endemic; these are the only genome sequences obtained from nondiseased individuals and of KSHV DNA isolated from saliva.

Results

Population structure analysis, along with the 25 published genome sequences from other parts of the world, showed whole-genome variation, separating sequences and variation within the central genome contributing to clustering of genomes by geography. We reveal new evidence for the presence of intragenic recombination and multiple recombination events contributing to the divergence of genomes into at least 5 distinct types.

Discussion

This study shows that large-scale genome-wide sequencing from clinical and epidemiological samples is necessary to capture the full extent of genetic diversity of KSHV, including recombination, and provides evidence to suggest a revision of KSHV genotype nomenclature.

Age of Infection with Kaposi Sarcoma-Associated Herpesvirus and Subsequent Antibody Values Among Children in Uganda

We investigated associations between Kaposi sarcoma-associated herpesvirus (KSHV) seroconversion age and KSHV antibody values in Ugandan children. Every annual delay in KSHV seroconversion age was associated with a reduction of 19% (P < 0.0001) in K8.1 and 27% (P < 0.0001) in ORF73 antibody values at 6 years of age. Early infection may be an important risk factor for KSHV pathogenesis and viral shedding in saliva, leading to transmission.

Human cytomegalovirus glycoprotein B inhibits migration of breast cancer MDA-MB-231 cells and impairs TGF-β/Smad2/3 expression

Breast cancer is a leading cause of cancer-associated mortality in females worldwide and evidence suggests that human cytomegalovirus (HCMV) infection may be implicated in the progress of breast cancer. HCMV glycoprotein B (gB) is the most abundant envelope protein and serves an important role in host cell entry. The present study aimed to clarify the role of HCMV gB in breast cancer cells. A HCMV gB construct (UL55) was generated and stable vUL55 gene lentivirus-transfected MDA-MB-231 cells were established. Subsequently, the effect of HCMV gB on the apoptosis and proliferation of MDA-MB-231 cells was measured by flow cytometry and Cell Counting Kit-8 assay. Furthermore, whether HCMV gB may modulate MDA-MB-231 cell migration was examined using Transwell and cell scratch assays. In addition, alterations in HCMV gB-modulated protein levels of transforming growth factor-β (TGF-β) and Mothers against decapentaplegic homologs 2/3 (Smad2/3) were detected using western blot analysis. The results indicated that UL55 cDNA was stably transfected into MDA-MB-231 cells, and that HCMV gB protein was stably expressed. No significant differences in cell apoptosis and proliferation between transfected (231-GB-OE) and negative control (231-NC) cells were observed, while the rate of cell migration was significantly decreased in the 231-GB-OE cells compared with the 231-NC cells. Additionally, the expression level of TGF-β and phosphorylation level of Smad2/3 were also decreased in 231-GB-OE cells compared with the 231-NC cells. Although certain previous studies indicated that HCMV infection was associated with breast carcinogenesis, the results of the present study indicate that the envelope protein HCMV gB exhibits no effect on cell apoptosis and proliferation, but inhibits breast cancer cell migration. This may be due to downregulated TGF-β/Smad signaling. Taken together, these studies may assist in developing anti-TGF-β agents that contribute to tumor suppression.

Detection of Human Herpes Virus 8 in Kaposi's sarcoma tissues at the University Teaching Hospital, Lusaka, Zambia

INTRODUCTION

Human herpes virus-8, a γ2-herpes virus, is the aetiological agent of Kaposi sarcoma. Recently, Kaposi's sarcoma cases have increased in Zambia. However, the diagnosis of this disease is based on morphological appearance of affected tissues using histological techniques, and the association with its causative agent, Human Herpes virus 8 is not sought. This means poor prognosis for affected patients since the causative agent is not targeted during diagnosis and KS lesions may be mistaken for other reactive and neoplastic vascular proliferations when only histological techniques are used. Therefore, this study was aimed at providing evidence of Human Herpes virus 8 infection in Kaposi's sarcoma tissues at the University Teaching Hospital in Lusaka, Zambia.

METHODS

One hundred and twenty suspected Kaposi's sarcoma archival formalin-fixed paraffin-wax embedded tissues stored from January 2013 to December 2014 in the Histopathology Laboratory at the University Teaching Hospital, Lusaka, Zambia were analysed using histology and Polymerase Chain Reaction targeting the ORF26 gene of Human Herpes virus 8.

RESULTS

The predominant histological type of Kaposi's sarcoma detected was the Nodular type (60.7%) followed by the plaque type (22.6%) and patch type (16.7%). The nodular lesion was identified mostly in males (40.5%, 34/84) than females (20.2%, 17/84) (p=0.041). Human Herpes virus 8 DNA was detected in 53.6% (45/84) and mostly in the nodular KS lesions (60%, 27/84) (p=0.035).

CONCLUSION

The findings in this study show that the Human Herpes virus-8 is detectable in Kaposi's sarcoma tissues, and, as previously reported in other settings, is closely associated with Kaposi's sarcoma. The study has provided important baseline data for use in the diagnosis of this disease and the identification of the virus in the tissues will aid in targeted therapy.

Incidence rate of Kaposi sarcoma in HIV-infected patients on antiretroviral therapy in Southern Africa: a prospective multicohort study

BACKGROUND

The risk of Kaposi sarcoma (KS) among HIV-infected persons on antiretroviral therapy (ART) is not well defined in resource-limited settings. We studied KS incidence rates and associated risk factors in children and adults on ART in Southern Africa.

METHODS

We included patient data of 6 ART programs in Botswana, South Africa, Zambia, and Zimbabwe. We estimated KS incidence rates in patients on ART measuring time from 30 days after ART initiation to KS diagnosis, last follow-up visit, or death. We assessed risk factors (age, sex, calendar year, WHO stage, tuberculosis, and CD4 counts) using Cox models.

FINDINGS

We analyzed data from 173,245 patients (61% female, 8% children aged <16 years) who started ART between 2004 and 2010. Five hundred and sixty-four incident cases were diagnosed during 343,927 person-years (pys). The overall KS incidence rate was 164/100,000 pys [95% confidence interval (CI): 151 to 178]. The incidence rate was highest 30-90 days after ART initiation (413/100,000 pys; 95% CI: 342 to 497) and declined thereafter [86/100,000 pys (95% CI: 71 to 105), >2 years after ART initiation]. Male sex [adjusted hazard ratio (HR): 1.34; 95% CI: 1.12 to 1.61], low current CD4 counts (≥500 versus <50 cells/μL, adjusted HR: 0.36; 95% CI: 0.23 to 0.55), and age (5-9 years versus 30-39 years, adjusted HR: 0.20; 95% CI: 0.05 to 0.79) were relevant risk factors for developing KS.

INTERPRETATION

Despite ART, KS risk in HIV-infected persons in Southern Africa remains high. Early HIV testing and maintaining high CD4 counts is needed to further reduce KS-related morbidity and mortality.

Multiplex PCR/mass spectrometry screening of biological carcinogenic agents in human mammary tumors

BACKGROUND

While many studies have suggested a possible link between breast cancer pathogenesis and infection by viruses, the role of viruses in breast carcinogenesis remains controversial.

OBJECTIVES

We analyzed the prevalence of 30 oncogenic human papillomaviruses (HPVs), Epstein-Barr virus (EBV), Kaposi's sarcoma herpes virus (KSHV) and six polyomaviruses in breast tumor specimens.

STUDY DESIGN

We analyzed breast specimens from 100 breast cancer patients (group 1) and 50 benign breast disease patients (group 2) from Shaanxi Province in China. We also screened for the viruses in blood samples from the patients and 96 female blood donor volunteers (group 3).

RESULTS

EBV, Merkel cell polyomavirus (MCPyV) and HPV-18 were detected in 60, 14 and 2 breast cancer patients, respectively, and EBV and MCPyV were detected in 16 and 1 benign breast disease patients, respectively. EBV and MCPyV were more prevalent in group 1 than in group 2 (EBV: 60.0% vs. 32.0%, p = 0.0012; MCPyV: 14.0% vs. 2.0%; p = 0.02). In contrast, there was no difference in the prevalence of EBV and MCPyV in blood samples between group 1 and group 2, group 1 and group 3. EBV was detected in malignant breast tissue and its presence was confined to the malignant cells using in situ hybridization.

CONCLUSIONS

We found that EBV and MCPyV were more prevalent in the tumors of women with breast cancer than in samples from women with benign breast disease. Our results support an etiologic role for EBV in breast cancer pathogenesis in Chinese patients.

Risk factors for early childhood infection of human herpesvirus-8 in Zambian children: the role of early childhood feeding practices

BACKGROUND

Human herpesvirus-8 (HHV-8) infection in early childhood is common throughout sub-Saharan Africa with prevalence increasing throughout childhood. Specific routes of transmission have not been clearly delineated, though HHV-8 is present in high concentrations in saliva.

METHODS

To understand the horizontal transmission of HHV-8 within households to children, we enrolled for cross-sectional analysis, 251 households including 254 children, age two and under, in Lusaka, Zambia. For all children, plasma was screened for HHV-8 and HIV type I (HIV-1) and health and behavioral questionnaires were completed. Multilevel logistic regression analysis was conducted to assess independent factors for HHV-8 infection in children.

RESULTS

Risk factors for HHV-8 infection included increasing number of HHV-8-positive household members [OR = 2.5; 95% confidence interval (CI), 1.9-3.3; P < 0.01] and having a primary caregiver who tested the temperature of food with their tongue before feeding the child (OR = 2.4; 95% CI, 1.93-3.30; P = 0.01). Breastfeeding was protective against infection with HHV-8 for children (OR = 0.3; 95% CI, 0.16-0.72; P < 0.01).

CONCLUSIONS

These results indicate that exposure to HHV-8 in the household increases risk for early childhood infection, with specific feeding behaviors likely playing a role in transmission.

IMPACT

Interventions to protect children from infection should emphasize the possibility of infection through sharing of foods.

Higher levels of neutralizing antibodies against KSHV in KS patients compared to asymptomatic individuals from Zambia

Kaposi sarcoma-associated herpesvirus (KSHV) is the etiologic agent for Kaposi Sarcoma (KS), the most common cancer diagnosed in HIV- infected patients. The role of neutralizing antibodies in KS pathogenesis and in KSHV infected individuals is not clearly understood. The goal of this study was to investigate and compare the prevalence and titers of neutralizing antibodies in plasma samples from KS patients and KSHV infected asymptomatic individuals from Zambia, a KS endemic region in sub-Saharan Africa. Plasma samples (N = 267) consisting of KS patients (group 1) and asymptomatic individuals (group 2) were collected from Lusaka, Zambia. A flow cytometry based quantitative neutralization assay utilizing recombinant KSHV expressing GFP was used to detect KSHV neutralizing antibodies. Our results show that the overall prevalence of neutralizing antibodies in KS patients (group 1) was 66.7% which was significantly higher than the prevalence of 6.5% present in KSHV infected asymptomatic individuals (group 2). Total antibody titers as well as neutralizing antibodies titers were found to be significantly higher among KS patients. It is likely that higher neutralizing antibodies prevalence and titers in KS patients result from higher levels of antigenic stimulation over time. This study is first to compare prevalence and titers of neutralizing antibodies in participants with and without disease from a KSHV endemic region.

Clinical outcomes of HIV-infected patients with Kaposi's sarcoma receiving nonnucleoside reverse transcriptase inhibitor-based antiretroviral therapy in Uganda

BACKGROUND

Clinical outcomes for patients with Kaposi's sarcoma (KS) using nonnucleoside reverse transcriptase inhibitor (NNRTI)-based highly active antiretroviral therapy (HAART) in resource-limited settings have not previously been described.

METHODS

We evaluated HIV-infected patients aged ≥ 18 years, who initiated HAART in the Home-Based AIDS Care (HBAC) project in Tororo, Uganda, between May 2003 and February 2008 and were diagnosed with KS at baseline or during follow-up. We examined independent risk factors for having either prevalent or incident KS and risk factors for death among patients with KS.

RESULTS

Of 1121 study subjects, 17 (1.5%) were diagnosed with prevalent KS and 18 (1.6%) with incident KS over a median of 56.1 months of follow-up. KS was associated with male sex [adjusted odds ratio (AOR) 2.41; 95% confidence interval (CI) 1.20-4.86] and baseline CD4 cell count < 50 cells/μL (AOR 3.25; 95% CI 1.03-10.3). Eleven (65%) of 17 patients with prevalent KS and 13 (72%) of 18 patients with incident KS experienced complete regression (P = 0.137). Eighteen (64%) of 28 patients who remained on NNRTI-based HAART experienced regression of their KS and six (86%) of seven patients who were switched to protease inhibitor-containing HAART regimens had regression of their KS (P = 0.23). Mortality among those with KS was significantly associated with visceral disease (hazard ratio 19.22; 95% CI 2.42-152).

CONCLUSION

Prevalent or incident KS was associated with 30% mortality. The resolution of KS lesions among individuals who initiated HAART with NNRTI-based regimens was similar to that found in studies using only protease inhibitor-based HAART.

HIV and cancer in Africa: mutual collaboration between HIV and cancer programs may provide timely research and public health data

The eruption of Kaposi sarcoma (KS) and aggressive non-Hodgkin lymphoma (NHL) in young homosexual men in 1981 in the West heralded the onset of the human immunodeficiency virus (HIV) infection epidemic, which remains one of the biggest challenges to global public health and science ever. Because KS and NHL were increased >10,000 and 50-600 times, respectively, with HIV, they were designated AIDS defining cancers (ADC). Cervical cancer (CC), increased 5-10 times was also designated as an ADC. A few other cancers are elevated with HIV, including Hodgkin lymphoma (10 times), anal cancer (15-30 times), and lung cancer (4 times) are designated as non-AIDS defining cancers (NADCs). Since 1996 when combination antiretroviral therapy (cART) became widely available in the West, dramatic decreases in HIV mortality have been observed and substantial decrease in the incidence of ADCs. Coincidentally, the burden of NADCs has increased as people with HIV age with chronic HIV infection. The impact of HIV infection on cancer in sub-Saharan Africa, where two thirds of the epidemic is concentrated, remains poorly understood. The few studies conducted indicate that risks for ADCs are also increased, but quantitatively less so than in the West. The risks for many cancers with established viral associations, including liver and nasopharynx, which are found in Africa, do not appear to be increased. These data are limited because of competing mortality, and cancer is under diagnosed, pathological confirmation is rare, and cancer registration not widely practiced. The expansion of access to life-extending cART in sub-Saharan Africa, through programs such as the Global Fund for AIDS, Malaria, and Tuberculosis and the US President's Emergency Program for AIDS Relief (PEPFAR), is leading to dramatic lengthening of life of HIV patients, which will likely influence the spectrum and burden of cancer in patients with HIV. In this paper, we review current literature and explore merits for integrating cancer research in established HIV programs to obtain timely data about the incidence and burden of cancer in HIV-infected persons in Africa.

Parasite infection is associated with Kaposi's sarcoma associated herpesvirus (KSHV) in Ugandan women

Background

Immune modulation by parasites may influence susceptibility to bacteria and viruses. We examined the association between current parasite infections, HIV and syphilis (measured in blood or stool samples using standard methods) and antibodies against Kaposi's sarcoma herpesvirus (KSHV), measured by ELISA, in 1915 stored plasma samples from pregnant women in Entebbe, Uganda.

Results

Seroprevalence of KSHV was higher in women with malaria parasitaemia (73% vs 60% p = 0.01), hookworm (67% vs 56% p = 0.001) and Mansonella perstans (69% vs 59% p = 0.05); seroprevalence increased with increasing intensity of hookworm infection (p < 0.001[trend]). No associations were found for HIV, five other parasites or active syphilis. These effects were not explained by socioeconomic status or education.

Conclusions

Specific parasite infections are associated with presence of antibodies against KSHV, perhaps mediated via their effect on immune function.

Human herpesvirus 8 seropositivity among sexually active adults in Uganda

Introduction

Sexual transmission of human herpesvirus 8 (HHV8) has been implicated among homosexual men, but the evidence for sexual transmission among heterosexual individuals is controversial. We investigated the role of sexual transmission of HHV8 in a nationally representative sample in Uganda, where HHV8 infection is endemic and transmitted mostly during childhood.

Materials and Methods

The study population was a subset of participants (n = 2681) from a population-based HIV/AIDS serobehavioral survey of adults aged 15–59 years conducted in 2004/2005. High risk for sexual transmission was assessed by questionnaire and serological testing for HIV and herpes simplex virus 2. Anti-HHV8 antibodies were measured using two enzyme immunoassays targeting synthetic peptides from the K8.1 and orf65 viral genes. The current study was restricted to 2288 sexually active adults. ORs and 95% CIs for HHV8 seropositivity were estimated by fitting logistic regression models with a random intercept using MPLUS and SAS software.

Results

The weighted prevalence of HHV8 seropositivity was 56.2%, based on 1302 seropositive individuals, and it increased significantly with age (P_trend<0.0001). In analyses adjusting for age, sex, geography, education, and HIV status, HHV8 seropositivity was positively associated with reporting two versus one marital union (OR:1.52, 95% CI: 1.17–1.97) and each unit increase in the number of children born (OR: 1.04, 95% CI: 1.00–1.08), and was inversely associated with ever having used a condom (OR: 0.64, 95% CI: 0.45–0.89). HHV8 seropositivity was not associated with HIV (P = 0.660) or with herpes simplex virus 2 (P = 0.732) seropositivity. Other sexual variables, including lifetime number of sexual partners or having had at least one sexually transmitted disease, and socioeconomic variables were unrelated to HHV8 seropositivity.

Conclusion

Our findings are compatible with the conclusion that sexual transmission of HHV8 in Uganda, if it occurs, is weak.

Substantial regional differences in human herpesvirus 8 seroprevalence in sub-Saharan Africa: insights on the origin of the "Kaposi's sarcoma belt"

Equatorial Africa has among the highest incidences of Kaposi's sarcoma (KS) in the world, thus earning the name "KS Belt." This was the case even before the HIV epidemic. To date, there is no clear evidence that HHV-8 seroprevalence is higher in this region but interpretation of the available literature is tempered by differences in serologic assays used across studies. We examined representatively sampled ambulatory adults in Uganda, which is in the "KS Belt," and in Zimbabwe and South Africa which are outside the Belt, for HHV-8 antibodies. All serologic assays were uniformly performed in the same reference laboratory by the same personnel. In the base-case serologic algorithm, seropositivity was defined by reactivity in an immunofluorescence assay or in 2 enzyme immunoassays. A total of 2,375 participants were examined. In Uganda, HHV-8 seroprevalence was high early in adulthood (35.5% by age 21) without significant change thereafter. In contrast, HHV-8 seroprevalence early in adulthood was lower in Zimbabwe and South Africa (13.7 and 10.8%, respectively) but increased with age. After age adjustment, Ugandans had 3.24-fold greater odds of being HHV-8 infected than South Africans (p < 0.001) and 2.22-fold greater odds than Zimbabweans (p < 0.001). Inferences were unchanged using all other serologic algorithms evaluated. In conclusion, HHV-8 infection is substantially more common in Uganda than in Zimbabwe and South Africa. These findings help to explain the high KS incidence in the "KS Belt" and underscore the importance of a uniform approach to HHV-8 antibody testing.

Seroprevalence of human herpesvirus 8 infection in individuals from health care centers in Mozambique: potential for endemic and epidemic Kaposi's sarcoma

Human herpesvirus 8 (HHV-8) infection is common in sub-Saharan Africa, but its prevalence in Mozambique is unknown. The seroprevalence of HHV-8 in a cohort of individuals seen at public health centers in Northern (n = 208), Central (n = 226), or Southern (n = 318) Mozambique was examined. All individuals were interviewed to obtain socioeconomic, demographic and clinical data and were tested for serum anti-HHV-8 antibodies using an immunofluorescence assay. The overall frequency of HHV-8 antibodies was 21.4% and, in spite of the diversity of epidemiological characteristics of the tested individuals, did not differ significantly among regions: 18.7%, 24.3% and 21.4% in the North, Center, and South, respectively (chi(2), 2.37; P = 0.305). The variables that were associated significantly with the presence of HHV-8 antibodies were gender, age, level of education, number of siblings and HIV serostatus, but these differed across the regions. In the North, although tested individuals lived under poor socioeconomic conditions, no association between HHV-8 infection and household variables was detected, with the exception of the number of siblings (P = 0.042). In the Central region, HHV-8 infection was associated with gender (P = 0.010), the number of household members (P = 0.031), and the place of attendance (P = 0.021). In the South, HHV-8 infection was associated with the number of siblings (P = 0.023) and HIV status (P = 0.002). The overall prevalence of HHV-8 seropositivity increased with age. These results demonstrate that Mozambique is another country in Africa with endemic HHV-8 infection, and, because of the AIDS epidemic, continued access to antiretroviral treatment is necessary to avert an outbreak of AIDS-Kaposi's sarcoma.

Kaposi sarcoma herpes virus antibody response and viremia following highly active antiretroviral therapy in the Swiss HIV Cohort study

OBJECTIVE

To describe the effect of HAART on Kaposi sarcoma herpes virus (KSHV) antibody response and viremia among HIV-positive MSM.

DESIGN

A follow-up study of 272 HIV-positive MSM (including 22 with Kaposi sarcoma) who first initiated HAART between January 1996 and July 2004 in the Swiss HIV Cohort Study.

METHODS

For each individual, two serum samples, one at HAART initiation and another 24 months later, were tested for latent and lytic KSHV antibodies using immunofluorescence assays, and for KSHV viremia using PCR. Factors associated with changes in KSHV antibody titers and viremia were evaluated.

RESULTS

At HAART initiation, 69.1 and 75.0% of patients were seropositive to latent and lytic KSHV antibodies, respectively. Seropositivity was associated with the presence of Kaposi sarcoma, older age, lower CD8 cell count and higher CD4/CD8 ratio. Prevalence of KSHV viremia at HAART initiation was 6.4%, being significantly higher among patients with Kaposi sarcoma (35.0%), and those with HIV viral loads 100 000 copies/ml (11.7%) or higher. At 24-month follow-up, geometric mean titers (GMTs) among KSHV seropositive patients increased and antibody seroprevalence was higher. Having Kaposi sarcoma and/or CD4 cell counts less than 50 cells/microl at HAART initiation was associated both with higher probability for antibody titers to increase (including seroconversion) and larger increases in GMTs. Only one of 17 viremic patients at HAART initiation had viremia at 24-month follow-up.

CONCLUSION

HAART increases KSHV-specific humoral immune response and clearance of viremia among HIV-infected MSM, consistent with the dramatic protection offered by HAART against Kaposi sarcoma.

Possible DNA viral factors of human breast cancer

Viruses are considered to be one of the high-risk factors closely related to human breast cancer. However, different studies of viruses in breast cancer present conflicting results and some of these works remain in dispute. DNA viruses, such as specific types of human papillomaviruses (HPV), Epstein–Barr virus (EBV), human cytomegalovirus (HCMV), herpes simplex virus (HSV), and human herpes virus type 8 (HHV-8), have emerged as causal factors of some human cancers. These respective exogenous viruses and the possibility of multiple viral factors are discussed in this review.

Socio-economic and other correlates of Kaposi sarcoma-associated herpesvirus seroprevalence among older adults in Sicily

The virus that causes Kaposi sarcoma, KS-associated herpesvirus (KSHV, also known as human herpesvirus 8) has an unusual distribution and poorly characterized modes of transmission. To clarify these issues, socio-demographic correlates of KSHV seroprevalence were examined in a population-based study. In 1,154 randomly sampled adults (aged 32- 92, mean 71 years) throughout Sicily, KSHV antibodies were detected with four assays and a conservative algorithm. Seroprevalence was re-weighted to the population. Odds ratios with 95% confidence intervals (OR, CI) from multivariate logistic regression were used to estimate associations of seroprevalence with interview data. KSHV seroprevalence was 8.5%, including 5.3% among men (N = 848) and 11.5% among women (N = 306, P = 0.22). Seroprevalence was higher with residence in a smaller community during childhood (P(trend) = 0.03) and working with plants/soil during adulthood (OR 2.9, CI 1.1-7.9); these were especially strong among women. Among men, seroprevalence was significantly associated with lower education (OR 2.6, CI 1.1-5.9) and migration to a larger community (OR 0.3, CI 0.1-0.9). Other demographic and household variables were unrelated to seroprevalence. From these data, KSHV in Sicily appears to be related to low socio-economic status, but micro-endemicity in small communities cannot be excluded.

Lack of evidence for frequent heterosexual transmission of human herpesvirus 8 in Zimbabwe

BACKGROUND

There is conflicting evidence about the contribution of heterosexual transmission to the spread of human herpesvirus 8 (HHV-8) in southern Africa. This study evaluated the hypothesis that HHV-8 infection is associated with risk factors for human immunodeficiency virus type 1 (HIV-1) and other sexually transmitted infections among Zimbabwean men.

METHODS

HHV-8 seroprevalence was determined for 2750 participants in the Zimbabwe AIDS Prevention Project cohort of male factory workers in Harare, Zimbabwe. Potential associations of HHV-8 antibody detection with risk factors for HIV-1 infection were examined by univariate analysis. Variables with P < .1 in the univariate analysis were included in a multivariate logistic regression model. HHV-8 seroprevalence was also determined among 297 heterosexual couples.

RESULTS

Prevalence of HHV-8, HIV-1, and HHV-8 and HIV-1 coinfection was 28.5% (95% confidence interval [CI], 26.8%-30.2%), 19.5% (95% CI, 18.0%-20.9%), and 6.5% (95% CI, 5.6%-7.5%), respectively. Detection of HHV-8 antibodies was independently associated with older age and HIV-1 infection but not with number of recent sex partners, marital status, education, condom use, prior sexually transmitted infections, payment for sex, chronic hepatitis B infection, or incident HIV-1 infection. HHV-8 seroprevalence was 31.7% (95% CI, 26.3-37.0) among wives in the couples tested, but HHV-8 infection of wives was not associated with HHV-8 infection of husbands (odds ratio, 1.08; 95% CI, 0.62-1.88; P = .8).

CONCLUSIONS

HHV-8 and HIV-1 infection did not have common sexual risk factors among urban Zimbabwean men. Sexual transmission does not explain the high prevalence of HHV-8 in this population.

Seroprevalence of Kaposi sarcoma-associated herpesvirus and other serologic markers in the Brazilian Amazon

To determine the presence of Kaposi sarcoma–associated herpesvirus (KSHV) and other serologic markers, we tested serum specimens of 339 Amerindians, 181 rural non-Amerindians, and 1,133 urban blood donors (13 Amerindians) in the Brazilian Amazon. High KSHV seroprevalence in children and inverse association with herpes simplex virus type 2 indicates predominant nonsexual transmission among Amerindians.

Human herpesvirus-8 (HHV-8) sero-detection and HIV association in Kaposi's sarcoma (KS), non-KS tumors and non-neoplastic conditions

Background

The association of the human herpesvirus-8/Kaposi's sarcoma (KS)-associated herpesvirus (HHV-8/KSHV) serology with various malignancies in Tanzania is not currently well established while previous studies were based on either PCR or immunofluorescence assays [IFA] but not with a sensitive enzyme-linked immunosorbent assay (ELISA). Selected archival diagnostic biopsies (n = 184) and sera from indigenous patients with KS (n = 120), non-KS tumors (n = 24) and non-neoplastic lesions (n = 40) at Muhimbili National Hospital (MNH), Tanzania, were evaluated by diagnostic histopathology, immunohistology [anti-HHV-8 latency-associated nuclear antigen (LANA)] and serology for HIV (ELISA) and HHV-8 (IFA and ELISA).

Results

About 66.3% (n = 122) cases including AIDS-associated Kaposi's sarcoma (AKS) (n = 93), reactive conditions (n = 28) and only one non-KS tumour were HIV positive. Endemic KS (EKS) patients were mostly males (96.3%, 26/27) who were less (69.9%, 65/93) predominant in AIDS-associated (AKS). A high (89%) percentage of patients with anti-HHV-8 antibodies was found in the cohort including the HIV positive (92%) cases, males (81.2%), KS patients (93%), non-KS tumors (92%), and reactive conditions (75%). All HHV-8 seronegative KS cases were nodular stage whereas both sera and corresponding biopsies from early stage KS were HHV-8+. Assay sensitivity, positive predictive value (PPV) and specificity were 98.6%, 93.5% and 16.7% for IFA and 93.5%, 98.6% and 50.0% for ELISA respectively.

Conclusion

HHV-8 seroprevalence at MNH appears high as expected among AKS cases and males but also in non-KS patients. ELISA showed a combination of high HHV-8 sensitivity as well as higher PPV and specificity than IFA which however, showed higher sensitivity. The apparent stage-dependent, inverted serum HHV-8 immunoreactivity supports a notion of viral immune-segregation during KS development. Routine HHV-8 screening should be considered particularly in patients at risk of KS and for selection of blood/organ donations.

A case-control study of cancer of the uterine cervix in Uganda

As part of an epidemiological study of cancer in Uganda, we investigated social, sexual and reproductive factors in relation to the risk of cancer of the uterine cervix. Patients with all cancer types or with benign tumours were recruited from hospitals in Kampala, Uganda, interviewed about various demographic and lifestyle factors and tested for antibodies against the human immunodeficiency virus-1 (HIV). The case-control study reported here involves 702 HIV-seronegative women, 343 of whom were diagnosed with cancer of the uterine cervix. Key findings were that the risk of cervical cancer increased linearly with the number of pregnancies [chi2(1)=44.7; P<0.0001]; a woman reporting having had 10 or more children had a roughly seven-fold increase in risk of the tumour as compared with women reporting fewer than four pregnancies (odds ratio=7.1; 95% confidence interval 3.8-13.2). The risk also varied inversely with age at first reported sexual intercourse [chi2(1)=8.4; P=0.004], perhaps reflecting an earlier age of infection with human papillomavirus, the main causal agent. These results are in line with those reported from studies in other countries.

Human herpesvirus-8 infection and oral shedding in Amerindian and non-Amerindian populations in the Brazilian Amazon region

BACKGROUND

Human herpesvirus type 8 (HHV-8) is hyperendemic in Amerindian populations, but its modes of transmission are unknown.

METHODS

Antibodies against either HHV-8 lytic antigen or HHV-8 latency-associated nuclear antigen (LANA) were detected, by immunofluorescence assays, in 339 Amerindians and 181 non-Amerindians from the Brazilian Amazon. Serological markers of oro-fecal (hepatitis A), parenteral (hepatitis B and C), and sexual (herpes simplex virus type 2 and syphilis) transmission were measured by specific ELISAs. Salivary HHV-8 DNA was detected by use of a nested polymerase chain reaction assay and was sequenced.

RESULTS

Antibodies against either lytic antigen or LANA were detected in 79.1% of Amerindians and in 6.1% of non-Amerindians (adjusted seroprevalence ratio [SR], 12.63 [95% confidence interval {CI}, 7.1-22.4]; P<.0001). HHV-8 seroprevalence increased with age among Amerindians (P(Trend) < .001) and already had high prevalence in childhood but was not sex specific in either population. The 2 populations did not differ in seroprevalence of oro-fecal or parenteral markers, but seroprevalence of markers of sexual transmission was lower among Amerindians. HHV-8 DNA in saliva was detected in 47 (23.7%) of 198 HHV-8 seropositive Amerindians. Detection of HHV-8 DNA decreased with age (P(Trend) < .04) and was more common in men (SR, 2.14 [95% CI, 1.3-3.5]; P=.003). A total of 36 (76.6%) of the 47 saliva HHV-8 DNA samples were sequenced, and all clustered as subtype E.

CONCLUSION

The data support the hypothesis of early acquisition and horizontal transmission, via saliva, of HHV-8 subtype E in Amerindian populations.

BK virus and cancer in Uganda

As part of an epidemiological study of cancer in Uganda, we investigated the titre of antibodies against BK virus among 821 people with different cancer types and benign tumours. Among study participants, 790 were considered seropositive for anti-BK virus antibodies and all analyses were conducted on transformed data. The mean optical density (a measure of antibody titre) for all patients combined (including the 31 who were considered seronegative) was 1.03 (standard error 0.01), but was 5% higher in women than in men (P=0.05), and 8% higher among HIV seropositive than seronegative people (P=0.002). Otherwise, there were few consistent associations between anti-BK virus antibodies and any social and lifestyle factor investigated. Differences in the mean optical density for each cancer type were estimated using multivariate analysis of variance with adjustment for sex, age group and HIV serostatus, using all other patients as controls. The mean optical density was about 17% lower among those with oral cancer (optical density 0.86, standard error 0.06; P=0.01, based on 30 patients) and about 20% higher among those with prostate cancer (optical density 1.22, standard error 0.09; P=0.01, based on 11 cases) than among all other patients combined. The number of cases of each cancer was too small to exclude the possibility of these findings arising by chance. No other cancer site or type was significantly associated with low, or with high anti-BK virus antibody titres.

Helicobacter pylori and cancer among adults in Uganda

Data from Africa on infection with Helicobacter pylori (H. pylori) are sparse. Therefore, as part of an epidemiological study of cancer in Uganda, we investigated the prevalence and determinants of antibodies against H. pylori among 854 people with different cancer types and benign tumours. Patients were recruited from hospitals in Kampala, Uganda, interviewed about various demographic and lifestyle factors and tested for antibodies against H. pylori. In all patients combined, excluding those with stomach cancer (which has been associated with H. pylori infection), the prevalence of antibodies was 87% (723/833) overall, but declined with increasing age (p = 0.02) and was lower among people who were HIV seropositive compared to seronegative (p < 0.001). Otherwise, there were few consistent epidemiological associations. Among those with stomach cancer, 18/21 (86%) had anti-H. pylori antibodies (odds ratio 0.8, 95% confidence intervals 0.2-2.9, p = 0.7; estimated using all other patients as controls, with adjustment for age, sex and HIV serostatus). No other cancer site or type was significantly associated with anti-H. pylori antibodies. The prevalence of H. pylori reported here is broadly in accord with results from other developing countries, although the determinants of infection and its' role in the aetiology of gastric cancer in Uganda remain unclear.

Relationship between viral factors, axillary lymph node status and survival in breast cancer

PURPOSE

Our previous study based on the results of polymerase chain reaction and Southern hybridization for the detection of Human papilloma virus (HPV), Cytomegalovirus (CMV), Epstein-Barr virus (EBV), Herpes simplex virus (HSV)-1, HSV-2, and Human herpesvirus (HHV)-8 DNA in non-familial breast cancer patients suggest that the viruses associated with breast cancer are HHV-8 > EBV (P < 0.01). Therefore, efforts were made to further investigate the association between breast cancer with nodal status and viral infections.

METHODS

Sixty-two breast cancer patients and their mammary specimens were enrolled in this retrospective study. The presence of these six potential oncogenic viruses was analyzed to establish the relationship between nodal status and treatment outcome. Statistical analyses were used for the assessment of variables, including viral positivity and clinical feature.

RESULTS

Viral positivity was not significantly different comparing node-positive and node-negative patients (P > 0.05). When the viral factors were not entered for statistical analyses, no variable was significantly related to overall survival. However, tumor stage, tumor size, nodal status , and estrogen receptor were significantly related to relapse-free survival (P < 0.05). For viral factors, the number of infecting viruses is related to the overall and relapse-free survivals. Only when V0 or V(0, 1) was grouped for comparison with other multiply virus-infected subgroups, were the overall and relapse-free survivals significantly different (P < 0.005 or P < 0.001). The results suggest that HSV-1, HHV-8, EBV, CMV, and HPV were related to overall survival, however, only HHV-8 and CMV were related to relapse-free survival (P < 0.05 or P < 0.01).

CONCLUSION

Virus factor is significantly related to human breast cancer, not only in terms of the oncogenetic process, but also in overall and relapse-free survivals.

A prospective study of Kaposi's sarcoma-associated herpesvirus and Epstein-Barr virus in adults with human immunodeficiency virus-1

Antibody titres against Kaposi's sarcoma associated herpesvirus (KSHV or human herpesvirus 8 (HHV-8)) and Epstein–Barr virus (EBV) were examined in people who subsequently developed Kaposi's sarcoma and non-Hodgkin's lymphoma, within randomised controlled trials of antiretroviral therapy in adults infected with the human immunodeficiency virus-1 (HIV). For each case of Kaposi's sarcoma (n=189) and each case of non-Hodgkin's lymphoma (n=67), which developed after randomisation, one control was randomly selected from other trial participants, after matching for age, sex, ethnicity, mode of HIV transmission, type of treatment received and period of follow-up. Using sera taken an average of two and a half years before the diagnosis of cancer, titres of antibodies against KSHV latent (LANA) and lytic (K8.1) antigens and against EBV (VCA) antigens were investigated in relation to subsequent risks of cancer by calculating odds ratios (OR) using conditional logistic regression. Latent antibodies against KSHV were detectable among 38% (72 out of 189) of Kaposi's sarcoma cases and 12% (23 out of 189) of their controls (OR=4.4, 95% confidence intervals (CI) 2.3–8.3, P<0.001). The OR for Kaposi's sarcoma increased with increasing antilatent KSHV antibody titre (χ²₁ for trend=32.2, P<0.001). Lytic antibodies against KSHV were detectable among 33% (61 out of 187) of Kaposi's sarcoma cases and 19% (36 out of 187) of their controls (OR=2.0, 95% CI 1.2–3.4, P=0.003) and the OR for Kaposi's sarcoma increased with increasing antilytic KSHV antibody titre (χ²₁ for trend=6.2, P=0.02). Virtually, all cases and controls had anti-EBV antibodies detected and the OR for non-Hodgkin's lymphoma associated with a doubling of the anti-EBV antibody titre was estimated to increase by a multiplicative factor of 1.3 (95% CI 0.9–1.7, P=0.1). Kaposi's sarcoma was not associated with antibody levels against EBV (P=0.4) and non-Hodgkin's lymphoma was not associated with antibodies against KSHV (latent P=0.3; lytic P=0.5). Adjustment for CD4 count at the time of sample collection made no material difference to any of the results. In conclusion, among human immunodeficiency virus infected people, high levels of antibodies against KSHV latent and lytic antigens are strongly associated with subsequent risk of Kaposi's sarcoma but not non-Hodgkin's lymphoma. Antibody titre to EBV does not appear to be strongly associated with subsequent risk of Kaposi's sarcoma or non-Hodgkin's lymphoma in HIV infected people.

Seroprevalence of six different viruses among pregnant women and blood donors in rural and urban Burkina Faso: A comparative analysis

A seroprevalence study was carried out of six different human pathogenic viruses, namely human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), human T-cell leukemia virus (HTLV), human herpesvirus type 8 (HHV-8), and dengue virus among pregnant women and blood donors from rural (Nouna) and urban (Ouagadougou) Burkina Faso, West Africa. A total of 683 samples from blood donors (n = 191) and pregnant women (n = 492) were collected from both sites and screened for the different virus infection markers resulting in the following prevalence values for Nouna or Ouagadougou, respectively: HIV 3.6/4.6, anti-HBV core (anti-HBc) 69.6/76.4, HBV surface antigen (HBsAg)14.3/17.3, HCV 2.2/1.5, HTLV 1.4/0.5, HHV-8 11.5/13.5, dengue virus 26.3/36.5. Individuals aged > or =25 years were more likely to be infected with HIV than those below 24 years (P < 0.05). Infection with HIV increased the likelihood of co-infection with other viruses, such as HHV-8, HBV and HTLV. Co-infection studies involving five viruses (HBV-HBsAg, HHV-8, HIV, HCV, and HTLV) showed that 4.8% (33/683) of the studied population were dually infected, with HBsAg+ HHV-8 (13/33), HBsAg+HIV (8/33) and HIV+HHV-8 (8/33) being the most common co-infections. Of the population studied 0.6% (4/683) was triply infected, the most common infection being with HBV+HIV+HHV-8 (3/4). There was no difference in the prevalence of HIV, anti-HBc, HBsAg, HCV, HTLV, and HHV-8 either among blood donors or pregnant women in urban or rural setting, while dengue virus prevalence was relatively lower in rural (26.3%) than in urban (36.5%) Burkina Faso.

Distribution of mosquito species in areas with high and low incidence of classic Kaposi's sarcoma and seroprevalence for HHV-8

The 'promoter-arthropod' hypothesis, which postulates that exposure to the bites of certain species of haematophagous arthropods is an environmental risk cofactor linked to human herpes virus 8 (HHV-8) and Kaposi's sarcoma, was investigated in the Po River valley, northern Italy. The presence and density of adult female mosquitoes (Diptera: Culicidae) was determined by CDC light trap catches in two adjacent districts, at variance with respect to Kaposi's sarcoma incidence and HHV-8 seroprevalence. A total of 3910 specimens belonging to 11 species was collected in 34 rural sites (six municipalities) representative of the two districts. Five of these species are considered to be possible 'promoters' because of the irritation their bites cause humans: Aedes vexans (Meigen) and Ae. caspius (Pallas) (87% of sampled promoters), Culex modestus Ficalbi, Culiseta annulata (Schrank) and Coquillettidia richiardii (Ficalbi). Six are probable 'non-promoters': Cx. pipiens s.l., Cx. martinii Medschid, Anopheles claviger (Meigen), An. maculipennis s.l., An. plumbeus Stephens and Uranotaenia unguiculata Edwards. The density of promoters by site was correlated with the incidence rates of Kaposi's sarcoma at the district level (Pearson's r = 0.33, P = 0.06) and at the municipal level (r = 0.50, P< 0.01). Similar correlations emerged for non-promoters (r = 0.48, P< 0.01 and r = 0.42, P = 0.01, respectively). The density of promoters was higher than that of non-promoters in sites with livestock (odds ratio, OR = 2.8, 95% CI 2.2-3.6) and in municipalities with Kaposi's sarcoma cases (OR = 2.5, 95% CI 1.7-3.5). The study provides additional evidence of the association between the density of some mosquito species and Kaposi's sarcoma.

Kaposi's sarcoma-associated herpesvirus: clinical, diagnostic, and epidemiological aspects

Kaposi's sarcoma-associated herpesvirus (KSHI) is one of the few viruses proven to be associated with tumorigenesis in humans. Its causal association with all clinical and epidemiological variants of Kaposi's sarcoma (KS) is well established. KSHV is also involved in the pathogenesis of primary effusion lymphoma (PEL) and a subset of multicentric Castleman's disease (MCD). Possible associations of KSHV with other clinical settings have been extensively examined. The findings from several of these studies are contradictory and are yet to be resolved. Concentrated effort over the last decade, since the initial discovery of KSHV, led to the development of several experimental systems that resulted in a better comprehension of the biological characteristics of KSHV and set the stage for the understanding of mechainisms by which diseases are induced by the virus. The development of molecular, histological, and serological tools for KSHV diagnosis allowed researchers to track the transmission and to study the epidemiology of KSHV. These assays have been applied, in particular in ambiguous cases, in order to confirm clinically and pathologically based diagnoses. Here, we review the advances in the clinical, experimental, diagnostic, and epidemiological research of KSHV.

Water, socioeconomic factors, and human herpesvirus 8 infection in Ugandan children and their mothers

BACKGROUND

Human herpesvirus 8 (HHV-8) infection is common in sub-Saharan Africa, but its distribution is uneven. Transmission occurs during childhood within families by unclear routes.

METHODS

We evaluated 600 Ugandan children with sickle cell disease and their mothers for factors associated with HHV-8 seropositivity in a cross-sectional study. HHV-8 serostatus was determined using an HHV-8 K8.1 glycoprotein enzyme immunoassay. Odds ratios for seropositivity were estimated using logistic regression, and factor analysis was used to identify clustering among socioeconomic variables.

RESULTS

One hundred seventeen (21%) of 561 children and 166 (34%) of 485 mothers with definite HHV-8 serostatus were seropositive. For children, seropositivity was associated with age, mother's HHV-8 serostatus (especially for children aged 6 years or younger), lower maternal education level, mother's income, and low-status father's occupation (P < 0.05 for all). Using communal standpipe or using surface water sources were both associated with seropositivity (OR 2.70, 95% CI 0.80-9.06 and 4.02, 95% CI 1.18-13.7, respectively) as compared to using private tap water. These associations remained, albeit attenuated, after adjusting for maternal education and child's age (P = 0.08). In factor analysis, low scores on environmental and family factors, which captured household and parental characteristics, respectively, were positively associated with seropositivity (P(trend) < 0.05 for both). For mothers, HHV-8 seropositivity was significantly associated with water source and maternal income.

CONCLUSIONS

HHV-8 infection in Ugandan children was associated with lower socioeconomic status and using surface water. Households with limited access to water may have less hygienic practices that increase risk for HHV-8 infection.

Association of viral factors with non-familial breast cancer in Taiwan by comparison with non-cancerous, fibroadenoma, and thyroid tumor tissues

To study the etiologic factors of non-familial breast cancer, the polymerase chain reaction (PCR) and Southern hybridization were used to detect six viruses including human papillomavirus (HPV), cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus (HSV)-1, HSV-2, and human herpesvirus (HHV)-8 DNA in 69 patients with breast cancer and 60 specimens from non-cancerous or other individuals with thyroid tumors or fibroadenoma (non-breast cancer controls). Two specimens from patients with a familial history of breast cancer and five breast cancer specimens with negative results for beta-globin, which was used as internal control, were excluded from this study. Eight (12.9%) HSV-1, 28 (45.2%) EBV, 47 (75.8%) CMV, 8 (12.9%) HPV, and 28 (45.2%) HHV-8 positive samples out of the 62 breast cancer specimens were detected; no HSV-2 DNA was detected in any group. Among the viral gene-positive breast cancer samples, 12 (23.1%) were positive for 1 virus, 16 (30.8%) were positive for 2 viruses, 21 (40.4%) were positive for 3 viruses, and 3 (5.8%) were positive for 4 viruses. Among the viral gene-positive specimens of the control groups, only one virus, CMV, was found in the non-cancerous and thyroid tumor specimens, while multiple viruses were found in the fibroadenoma specimens. The viruses associated with breast cancer were HHV-8 > EBV (P <0.01). The viruses associated with fibroadenoma were HSV-1 and HHV-8 > EBV (P <0.01). The presence of more than one virus was found predominantly in breast cancer and exclusively found in fibroadenoma. CMV was the only virus associated with thyroid tumors.

Human herpesvirus type 8 infection in an area of Northern Italy with high incidence of classical Kaposi's sarcoma

Previous studies have reported a large variation in the incidence of classical Kaposi's sarcoma across different Districts of the province of Mantua (Northern Italy). To assess whether such differences might be explained by different anti-HHV8 antibody prevalence, a serological study was conducted in 343 healthy elderly individuals resident in two adjacent Districts, at the highest and the lowest classical Kaposi's sarcoma incidence rate, respectively. Qualitative and quantitative determinations of IgG antibodies against both latent and lytic HHV-8 antigens were performed by indirect immunofluorescence assay. The assay's sensitivity was studied in 26 patients with classical Kaposi's sarcoma. Overall, anti-HHV8 antibodies were detected in 25 out of 26 patients (96%), confirming the high sensitivity of this assay. The prevalence of anti-HHV-8 antibodies was higher among individuals living in the District had a high incidence of classical Kaposi's sarcoma compared to those living in the District with low incidence (19.4% vs 9.8%, and 15.9% vs 8%; P<0.05, for latent and lytic antibodies, respectively). Anti-lytic antibody GMT was higher in people living in the District at high incidence rate compared to those of the other area (328.9 vs. 180.4; P<0.01). A higher prevalence of HHV-8 infection was found among persons living in municipalities surrounded by watercourses (OR 2.2, 95% CI: 1.10-4.32). In conclusion, variation in HHV-8 prevalence appears to explain differences in the incidence rates of classical Kaposi's sarcoma observed in different areas of the province.

AIDS-associated cancer in developing nations

PURPOSE OF REVIEW

With the emergence of the highly active antiretroviral therapy era, it is apparent that the incidence of Kaposi sarcoma, in particular, and lymphoma in patients with AIDS is declining, especially in regions of the world where these regimens are routinely available. The burden of HIV infection and AIDS is greatest in the developing world, and no doubt neoplastic complications are increasingly encountered. The purpose of this review is to highlight recent developments of this aspect of the AIDS epidemic in the developing world.

RECENT FINDINGS

It was readily apparent that the incidence of Kaposi sarcoma sharply increased after the onset of the AIDS epidemic in developing countries. By the end of the second decade of the epidemic, non-Hodgkin lymphoma is increasing in incidence and the natural history of Burkitt lymphoma is evolving in the backdrop of HIV infection as well. Cervical cancer is the most common cancer in women in many developing countries, yet the true impact of HIV infection on the development of this neoplasm is not fully understood. Squamous cell carcinoma of the conjunctiva appears to be a unique AIDS-associated neoplasm that is encountered in sub-Saharan Africa as well. Finally, although the epidemiologic and clinicopathologic features for many AIDS-associated neoplasms are well characterized in developing regions of the world, there is a paucity of data on the therapeutic approach to these tumors in this setting.

SUMMARY

It is apparent that as the AIDS pandemic proceeds, the burden of neoplastic diseases is increasing in developing nations. Current therapeutic approaches are not well documented. Pragmatic prevention and therapeutic interventions suitable for the resource-constrained setting are clearly needed.

Risk of malignant lymphoma associated with human herpesvirus-8: a case-control study in Spain

No overall increased risk of lymphoma associated with antibodies to human herpesvirus-8 was found in 526 lymphomas and 599 controls (odds ratio (OR)=1.04, 95% confidence interval (CI)=0.62–1.75); significant increases were noted for 19 lymphoplasmacytic lymphomas (OR=4.47, 95% CI=1.34–14.85) and nine low-grade lymphoma/lymphoma B-cell NOS (OR=5.82, 95% CI=1.07–31.73).

Human papillomaviruses and cancer in Uganda

In a case-control study in Uganda, we examined associations between different cancer sites or types in relation to antibodies against human papillomaviruses (HPV)-16, -18 and -45. For each cancer site or type, the control group comprised all other cancers excluding those known, or thought to be associated with HPV infection (cancers of the uterine cervix, penis and eye). Among controls the seroprevalence of antibodies was 11% (68/616) against HPV-16, 5% (29/605) against HPV-18 and 6% (35/605) against HPV-45. Antibodies against HPV-16 were significantly associated with only two cancers: uterine cervix [prevalence of antibodies 27% (51/191); odds ratio (OR) 2.0, 95% confidence interval (CI) 1.2-3.1, P=0.01] and penis [prevalence of antibodies 27% (4/15); OR 6.4, 95% CI 1.7-24.3, P=0.01]. For both cancers, the risk increased with increasing anti-HPV-16 antibody titre (Ptrend=0.01 for each). No cancer site or type was significantly associated with antibodies against HPV-18 and -45.

Epidemiological characteristics of human herpesvirus-8 infection in a large population of antenatal women in Zambia

Comprehensive data describing epidemiological characteristics of the human herpesvirus-8 or Kaposi's sarcoma-associated herpesvirus (HHV-8 or KSHV) infection among pregnant women in a central sub-Saharan Africa are not available. This study determined virus prevalence estimates and the risk factors associated with HHV-8 infection. Cross-sectional, enrollment visit data were analyzed from a prospective cohort study of perinatal transmission of HHV-8 in Lusaka, Zambia. Exposure data were obtained via structured interview, physical examination, medical chart review, and laboratory testing. Among 3,160 antenatal women serologically screened for HHV-8 between September 1998 and October 2000, 40.2% were seropositive. The HHV-8 positive women were more likely to be co-infected with HIV-1 than those who were HHV-8 negative (34% vs. 26%; P < 0.0001). Of 154 variables evaluated by logistic regression analyses, only three risk factors, have emerged as independent predictors of HHV-8 positive serology: diagnosis of genital warts, HIV-1 co-infection and primary education. The association of HHV-8 infection with genital warts and HIV-1 co-infection suggests heterosexual transmission of HHV-8. HIV-1 infection may also act as a marker for particular behaviors, which could be sexual in nature, that are associated with both HIV-1 and HHV-8 transmission. Since HHV-8 facilitates development of AIDS-related Kaposi's sarcoma (KS), the results of this study could be utilized to identify specific population groups of pregnant women who are at increased risk for this disease.

Reduced seroprevalence of Kaposi's sarcoma-associated herpesvirus (KSHV), human herpesvirus 8 (HHV8), related to suppression of Anopheles density in Italy

In two formerly malarious parts of Italy, age-related seroprevalence rates of Kaposi's sarcoma-associated herpesvirus [human herpesvirus 8 (KSHV/HHV8)] were determined from local blood donors and correlated with periods of vector control during anti-malaria campaigns. In Veneto, decreased KSHV/HHV8 seroprevalence in the 1951-1955 birth cohort coincides with the peak of DDT house-spraying. In Sardinia, where larviciding augmented indoor DDT-spraying, a significant drop of KSHV/HHV8 seroprevalence between 1945 and 1950 and 1951-1955 birth cohorts (P = 0.0046) coincides with suppression of the malaria vector Anopheles labranchiae Falleroni (Diptera: Culicidae). These results are consistent with age-related association between KSHV/HHV8 seroprevalence rates in native/resident populations and the density of malaria vectors in Veneto and Sardinia. This example supports our 'promoter arthropod' hypothesis on the role of haematophagous insects [putatively blackflies (Simuliidae), sandflies (Phlebotominae) and biting midges (Ceratopogonidae), as well as mosquitoes] when their bites induce hypersensitivity and immunosuppression, potentiate KSHV/HHV8 transmission via human saliva (when insect bite lesions are licked by another person whose saliva carries the virus) and may facilitate Kaposi's sarcoma.

Risk factors for high anti-HHV-8 antibody titers (> or =1:51,200) in black, HIV-1 negative South African cancer patients: a case control study

BACKGROUND

Infection with human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma-associated herpesvirus (KSHV), is the necessary causal agent in the development of Kaposi's sarcoma (KS). Infection with HIV-1, male gender and older age all increase risk for KS. However, the geographic distribution of HHV-8 and KS both prior to the HIV/AIDS epidemic and with HIV/AIDS suggest the presence of an additional co-factor in the development of KS.

METHODS

Between January 1994 and October 1997, we interviewed 2576 black in-patients with cancer in Johannesburg and Soweto, South Africa. Blood was tested for antibodies against HIV-1 and HHV-8 and the study was restricted to 2191 HIV-1 negative patients. Antibodies against the latent nuclear antigen of HHV-8 encoded by orf73 were detected with an indirect immunofluorescence assay. We examined the relationship between high anti-HHV-8 antibody titers (> or =1:51,200) and sociodemographic and behavioral factors using unconditional logistic regression models. Variables that were significant at p = 0.10 were included in multivariate analysis.

RESULTS

Of the 2191 HIV-1 negative patients who did not have Kaposi's sarcoma, 854 (39.0%) were positive for antibodies against HHV-8 according to the immunofluorescent assay. Among those seropositive for HHV-8, 530 (62.1%) had low titers (1:200), 227 (26.6%) had medium titers (1:51,200) and 97 (11.4%) had highest titers (1:204,800). Among the 2191 HIV-1 negative patients, the prevalence of high anti-HHV-8 antibody titers (> or =1:51,200) was independently associated with increasing age (p-trend = 0.04), having a marital status of separated or divorced (p = 0.003), using wood, coal or charcoal as fuel for cooking 20 years ago instead of electricity (p = 0.02) and consuming traditional maize beer more than one time a week (p = 0.02; p-trend for increasing consumption = 0.05) although this may be due to chance given the large number of predictors considered in this analysis.

CONCLUSIONS

Among HIV-negative subjects, patients with high anti-HHV-8 antibody titers are characterized by older age. Other associations that may be factors in the development of high anti-HHV-8 titers include exposure to poverty or a low socioeconomic status environment and consumption of traditional maize beer. The relationship between these variables and high anti-HHV-8 titers requires further, prospective study.

Infection with Kaposi's sarcoma-associated herpesvirus (KSHV) and human immunodeficiency virus (HIV) in relation to the risk and clinical presentation of Kaposi's sarcoma in Uganda

A case-control study from Uganda found that the risk of Kaposi's sarcoma increased with increasing titre of antibodies against Kaposi's sarcoma-associated herpesvirus (KSHV) latent nuclear antigens, independently of HIV infection. Clinically, widespread Kaposi's sarcoma was more frequent among patients with HIV infection than in those without, but was not related to anti-KSHV antibody titres.

Epidemiology of AIDS-related malignancies an international perspective

Patients with HIV infection are at increased risk for developing Kaposi's sarcoma, non-Hodgkin's lymphoma, and several other cancers. The relative risks for the most common epithelial cancers in the general population--lung, breast, colon/rectum, stomach, liver, and prostate--are not increased substantially in people with AIDS, however. Accumulating data suggest that HIV-infected patients also are at increased risk for developing Hodgkin's lymphoma, cervical carcinoma in situ (CIS), other anogenital neoplasms (invasive cancer and CIS), leiomyosarcoma, and conjunctival squamous cell carcinoma. There is inconclusive evidence, however, with regard to HIV infection being associated with invasive cervical cancer, testicular seminoma, or hepatocellular carcinoma. Notably, other viral infections have been implicated in the etiology of many of these conditions. The introduction of highly active antiretroviral therapy (HAART) has decreased the incidence of AIDS-associated cancers in Western countries, but less than 1% of AIDS patients are receiving HAART in the HIV epicenter of sub-Saharan Africa. Further therapeutic advances that extend survival with HIV infection with varying reconstitution of immune competence may lead to additional alterations in cancer risk.