Human herpesvirus 8 seroprevalence among Tobago women and the role of sexual lifestyle behavior

Epidemiology of Cervical Cancer in the Caribbean

Cervical cancer (CvC) is considered a preventable disease; however, in the Caribbean, it is still one of the fourth most common causes of death in women. Efforts to overcome obstacles to the treatment and control of this preventable disease are being made by several countries within the Caribbean. However, no health issue can be readily managed without first acquiring an understanding of the dynamics relating to its severity of impact reaching the target population, its clinical pathology, and the availability of treatment and/or preventative measures to control or halt its progression. To assess the status of CvC in the Caribbean, a review of the literature was conducted using PubMed. The Caribbean was defined in the review as comprising nations and islands whose coastlines are touched by the Caribbean Sea. This led to an assessment of the available literature on CvC for 33 Caribbean territories. The review showed a lack of published information on CvC and highlights the need for greater research. This also serves as a template for subsequent investigations.

Prevalence and Risk Factors of Human Herpes Virus Type 8 (HHV-8), Human Immunodeficiency Virus-1 (HIV-1), and Syphilis among Female Sex Workers in Malindi, Kenya

The prevalence of Human Herpes Virus type 8 (HHV-8), Human Immunodeficiency virus (HIV), and syphilis is high in Sub-Saharan Africa. Studies on HHV-8 in Kenya are few and data on its coinfection with HIV and syphilis scanty. This cross-sectional study among female sex workers (FSWs) in Malindi, Kenya, aimed to determine the prevalence of HHV-8, HIV, and syphilis mono/coinfections and identify associated risk factors. A total of 268 FSWs consented and were administered a structured questionnaire and screened for antibodies against HHV-8, HIV, and syphilis following the National Guidelines. FSWs positive for HHV-8 were 67/268 (25%), HIV 44/268 (16.4%), and 6/268 (2.24%) for syphilis. Eight out of 67 (12%) tested positive for HHV-8/HIV and 2/67 (3%) for HHV-8/syphilis coinfections. Married FSWs had higher odds of HHV-8 infection (OR 2.90, 95%, and P=0.043). Single marital status was inversely associated (OR 0.46, 95% CI 0.23-0.94, and P=0.034) with HIV infection. HIV was associated with increasing age (OR 14.79, P<0.001), inconsistent condom use (OR 2.69, P=0.004), increased duration as sex worker ≥6 (OR 3.0, P=0.002) and clients ≥4 (OR 4.0, P<0.001), intravenous drug use (OR 2.5, P=0.043), and early sex debut (P=0.049) unlike HHV-8 which was not associated with high risk sexual behavior. HHV-8/HIV coinfection was associated with increasing age (OR 11.21, P=0.027). Infection by HHV-8 was not significantly associated with HIV (OR 0.62; P=0.257) or syphilis (OR 1.52; P=0.636). There was a high likelihood of infection with HHV-8 compared to HIV (OR 8.6, P=0.014) and syphilis (OR 14.6, P<0.001). The lack of association of HHV-8 with high risk sexual behavior suggests that sexual transmission may not play a significant role in transmission of HHV-8 among FSWs in Malindi.

Human herpesvirus 8 establishes a latent infection in prostates of Tobago men resulting in increased macrophage infiltration

BACKGROUND

The Caribbean island of Tobago, which is 97% African ancestry, has one of the highest rates of prostate cancer in the world. We have previously reported that human herpesvirus 8 (HHV-8) infection is significantly associated with prostate cancer in Tobago. In this study, we extend those results testing the hypothesis that HHV-8 seropositive Tobagonian men have a chronic HHV-8 infection in their prostates that is associated with increased inflammation.

METHODS

Prostate sections were screened by immunohistochemistry for the expression of HHV-8 proteins K8.1 and LANA-1 and for presence of B cells (CD20) and macrophages (CD68).

RESULTS

HHV-8 antigen expression representing lytic and latent infections was seen in 73.9% of prostates from HHV-8 seropositive subjects. Latent infections were seen predominantly in glandular epithelia whereas lytic gene expression was seen mainly in macrophages in prostate stroma. Macrophage infiltrates were significantly increased in sections expressing HHV-8 proteins.

CONCLUSION

HHV-8 establishes a chronic latent infection in the prostate, which is associated with an increased macrophage infiltrate.

Human herpesvirus 8 seroconversion in a population-based cohort of men in Tobago

Human herpesvirus 8 (HHV-8) is the causal agent of Kaposi's sarcoma (KS). In Tobago, KS is not common; however, HHV-8 seropositivity has been reported to be 39.9% in men with prostate cancer compared to <22.9% in healthier women and men. To understand HHV-8 transmission, we examined HHV-8 seroconversion and seroreversion, and risk factors for these changes in Tobago men. Serum specimens from a sub-cohort of Tobago Prostate Survey men, aged 40-81 years (n = 381/442), were collected at baseline and a subsequent visit between 3 and 9 years and tested for HHV-8 seropositivity using an immunofluorescence assay for antibodies against HHV-8 lytic antigens. Poisson distribution was used to calculate HHV-8 seroconversion and seroreversion rates and their 95% confidence intervals. Differences in baseline characteristics between HHV-seroconverters versus persistent HHV-8 seronegative men and HHV-8 seroreverters versus HHV-8 seropositive men were examined. HHV-8 seropositivity was 12.3% (N = 381) at baseline, with HHV-8 seropositivity significantly higher in increasing age groups, 40-49 (4.0%) to 70-81 (37.5%) years (P-value trend <0.0001). HHV-8 seroconversion and seroreversion rates were 0.23 per 100 person-years (95% C.I., 0.06-0.58) and 2.42 per 100 person-years (95% C.I., 0.89-5.26), respectively. There were significantly more HHV-8 seroconverters who reported "ever smoked cigarettes of >6 months" at baseline compared to HHV-8 persistent seronegative men (P-value = 0.03). Baseline characteristics of HHV-8 seroreverters did not differ from persistent seropositive men. Low HHV-8 seroconversion and seroreversion rates were found. Data suggest that HHV-8 transmission occurred at earlier ages, <40 years, in Tobago men.

A case-cohort study of human herpesvirus 8 seropositivity and incident prostate cancer in Tobago

Background

We previously reported a cross-sectional association between the presence of human herpesvirus 8 (HHV-8) serum antibodies and screen-detected prostate cancer in men living in Tobago. In the same study population, we examined the association between HHV-8 seropositivity and incident prostate cancer discovered at later screenings.

Methods

In 40-81 year-old men without prostate cancer discovered at initial digital rectal examination (DRE) and prostate-specific antigen (PSA) screening, a case-cohort design measured the association between baseline HHV-8 seropositivity (modified immunofluorescence assay for antibodies against HHV-8 lytic antigens) and incident prostate cancer detected at DRE and PSA screenings three or five years later.

Results

Analyses included 486 unique individuals, 96 incident prostate cancer cases, and 415 randomly selected subjects representing an at-risk cohort. By design, the random sub-cohort contained 25 incident prostate cancer cases. In the sub-cohort, the frequency of HHV-8 seropositivity increased across age groupings (40-49 years: 3.5%, 50-59 years: 13.6%, and ≥ 60 years: 22.9%). HHV-8 seropositivity was higher in men with elevated (≥ 4.0 ng/mL) than men with non-elevated PSA at initial screening (30.4% vs. 9.9% seropositive; crude odds ratio (OR) 3.96, 95% confidence interval (CI) 1.53-10.2; age-adjusted OR 2.42, 95% CI 0.91-6.47). HHV-8 seropositivity did not increase incident prostate cancer risk (age-adjusted hazard ratio (HR) 0.88, 95% CI 0.46-1.69).

Conclusions

Case-cohort analysis did not identify association between HHV-8 seropositivity and incident prostate cancer. However, analyses uncovered possible association between HHV-8 and PSA (a marker of prostate inflammation). Co-occurrence of HHV-8 seropositivity and PSA elevation may explain cross-sectional association between HHV-8 and PSA screen-detected prostate cancer.

Do fewer cases of Kaposi's sarcoma in HIV-infected patients reflect a decrease in HHV8 seroprevalence?

Infection with human herpes virus 8 (HHV8) is associated with development of Kaposi's sarcoma (KS); therefore also known as KS-associated herpes virus. KS is closely associated with human immunodeficiency virus (HIV) infection, and consequently HHV8 seroprevalence is higher in HIV-infected compared to HIV-negative patients. Currently, KS is rarely seen in clinical practice, which might be a consequence of an optimized anti-HIV treatment leading to an improved immunological status, or alternatively of a decrease in HHV8 prevalence. To determine the prevalence of HHV8 antibodies in HIV-positive compared to HIV-negative patients from the University Hospital Frankfurt/Main, Germany, and to compare our results with previously published data to illustrate trends in the spread of infection. Hundred serum samples each of HIV-positive and HIV-negative patients were analyzed for HHV8 antibodies by using an IgG immunofluorescence test. The overall HHV8 seroprevalence was 16% with no statistically significant gender-specific differences; however, the distribution between the HIV-infected patients and the HIV-negative control group was significantly different (30 and 2%, respectively). The highest rate of seroprevalence in HIV-infected patients was detected at the age of 40-49 (42%) and the lowest rate at the age of 20-29 years (16.6%). In comparison with formerly conducted studies, our data clearly showed an increase in the HHV8 seroprevalence in HIV-infected patients, both in men and women. Therefore, we conclude that the low rate of clinical KS is associated with an improved immunological status due to an optimized anti-HIV therapy.