Herpes simplex virus type 2 acquisition during recent HIV infection does not influence plasma HIV levels

No Role of Herpes Simplex Virus Type 2 (HSV-2) Infection on HIV Progression in Naïve HIV Patients

Background:

Herpes simplex virus type 2 (HSV-2) is a common infection in human immunodeficiency virus (HIV) patients and may accelerate HIV progression by rising HIV viral load and decreasing CD4 count. However, the available data regarding the influence of HSV-2 seropositivity on HIV progression in HIV individuals are inconclusive. Therefore, we aimed to determine HSV-2 seroprevalence in naïve HIV patients and normal controls and also investigate the relation of HIV viral load and CD4 count with HSV-2 seropositivity. Subsequently, we investigated the association of HSV-2 serostatus with changing in CD4 count and HIV viral load in our subjects, after one year follow-up.

Methods:

In this study, 116 naïve HIV patients and 85 healthy controls from Tehran, Iran were enrolled. HSV-2 IgG antibody was detected by ELISA. CD4 count was determined by flowcytometry, and serum HIV RNA copy numbers were determined using real-time PCR.

Results:

The prevalence of HSV-2 IgG was 18.1% in naïve HIV patients and 0% in the control group (P = 0.000). HSV-2 seroconversion was observed in 2.43% of HIV patients after one year. There was no significant difference regarding HSV-2 serostatus with CD4 count and HIV RNA viral load in our study cohort at baseline and after one year.

Conclusion:

Our results revealed that the prevalence and incidence of HSV-2 infection are low in our HIV cases, and it is negligible in the control group. However, it seems that HIV/HSV2 co-infection has no role on HIV infection acceleration.

Seminal Shedding of CMV and HIV Transmission among Men Who Have Sex with Men

As in many urban areas in the United States, the largest burden of the HIV epidemic in San Diego is borne by men who have sex with men (MSM). Using data from well-characterized HIV transmitting and non-transmitting partner pairs of MSM in San Diego, we calculated the population attributable risk (PAR) of HIV transmissions for different co-infections common among MSM in this area. We found that over a third of HIV transmissions could be potentially attributed to genital shedding of cytomegalovirus (CMV) (111 transmission events), compared to 21% potentially attributed to bacterial sexually transmitted infections (STI) (62 events) and 17% to herpes simplex virus type-2 (HSV-2) (51 events). Although our study cannot infer causality between the described associations and is limited in sample size, these results suggest that interventions aimed at reducing CMV shedding might be an attractive HIV prevention strategy in populations with high prevalence of CMV co-infection.

Herpes simplex virus type 2 and HIV disease progression: a systematic review of observational studies

Background

Herpes simplex virus type 2 (HSV-2) is a common co-infection among HIV-infected adults that is hypothesized to accelerate HIV disease progression.

Methods

We searched Medline, EMBASE, relevant conference proceedings (2006–12) and bibliographies of identified studies without language restriction for cohort studies examining the impact of HSV-2 on highly active antiretroviral therapy-untreated HIV disease in adults. The exposure of interest was HSV-2 seropositivity or clinical/laboratory markers of HSV-2 activity. The primary outcome was HIV disease progression, defined as antiretroviral initiation, development of AIDS/opportunistic infection, or progression to CD4 count thresholds (≤200 or ≤350 cells/mm³). Secondary outcomes included HIV plasma viral load and CD4 count.

Results

Seven studies were included. No definitive relationship was observed between HSV-2 seropositivity and time to antiretroviral initiation (n=2 studies), CD4≤350 (n=1), CD4≤200 (n=1), death (n=1), viral load (n=6) or CD4 count (n=3). Although two studies each observed trends towards accelerated progression to clinical AIDS/opportunistic infection in HSV-2 seropositives, with pooled unadjusted hazard ratio=1.85 (95% CI=1.12,3.06; I²=2%), most OIs observed in the study for which data were available can occur at high CD4 counts and may not represent HIV progression. In contrast, a single study HSV-2 disease activity found that the presence of genital HSV-2 DNA was associated with a 0.4 log copies/mL increase in HIV viral load.

Conclusions

Despite an observation that HSV-2 activity is associated with increased HIV viral load, definitive evidence linking HSV-2 seropositivity to accelerated HIV disease progression is lacking. The attenuating effects of acyclovir on HIV disease progression observed in recent trials may result both from direct anti-HIV activity as well as from indirect benefits of HSV-2 suppression.

Association between herpes simplex virus type 2 and HIV-1 in a population of married couples from Dakar, Senegal

Numerous studies suggest that herpes simplex virus type 2 (HSV-2) increases the risk of HIV-1 infection but recent clinical trials of HSV-2 suppressive therapy failed to show an effect. We assessed the putative association between HSV-2 and HIV-1 in a population of HIV-concordant-negative, HIV-1-discordant and HIV-1-concordant-positive married couples from Dakar, Senegal. In agreement with previous studies, we observed a strong overall association between HSV-2 and HIV-1 (odds ratio 4.61; P < 0.001). However, this association was mainly determined by a low HSV-2 prevalence in HIV-concordant-negative couples compared with HIV-1-discordant and HIV-1-concordant-positive couples (23% versus 59% and 66%, respectively; P < 0.001). We observed no further differences in HSV-2 prevalence between HIV-1-discordant and HIV-1-concordant-positive couples (59% and 66%, respectively; P = 0.483). Neither the index (59% versus 62%, P = 1.000) nor recipient partners (41% versus 63%, P = 0.131) in HIV-1-discordant and HIV-1-concordant-positive couples showed significant differences in HSV-2 prevalence. HSV-2 does not constitute a clear risk factor for HIV-1 infection in this population.

Incidence, prevalence, and epidemiology of herpes simplex virus-2 in HIV-1-positive and HIV-1-negative adolescents

BACKGROUND

Several studies have assessed risk factors associated with herpes simplex virus-2 (HSV-2) prevalence in adults; however, few have focused on HSV-2 incidence, particularly in adolescents. The objective of this study was to determine HSV-2 prevalence and incidence and associated risk factors in a HIV-1-positive and at risk HIV-1-negative adolescent population.

METHODS

Sera were tested for HSV-2 antibodies in 518 adolescents in the Reaching for Excellence in Adolescent Care and Health cohort at baseline and again at the final follow-up visit. Prevalence at baseline and incidence (per person years) of HSV-2 infection were calculated. Furthermore, among HIV-1-positive individuals, a subgroup analysis was performed to assess risk factors for HSV-2 infection. Conditional logistic regression was used to estimate odds ratios and P values for associations between CD4+ T-cell (CD4+) count, HIV-1 viral load (VL), and HSV-2 acquisition, adjusting for antiretroviral therapy use, other sexually transmitted infections, gender, race, and number of sexual partners.

RESULTS

At baseline, 179 (35%) subjects were HSV-2 positive, with an additional 47 (16%) new cases being identified during a median follow-up time of 1.95 years and an incidence rate of 7.35 cases per 100 person years. Several risk factors were associated with HSV-2 prevalence (being female, non-Hispanic, uncertainty of sexual preference, and HIV-1 positive) and incidence (using drugs, alcohol, and number of new sexual partners). Among HIV-1 positives, an increase in CD4+ count by 50 cell/mm(3) (odds ratio, 1.17; 95% CI, 1.04-1.31, P = 0.008) was associated with HSV-2 acquisition.

CONCLUSIONS

The high prevalence and incidence of HSV-2 infection among adolescents, compared with the general population at this age group suggests a critical need for screening and preventive programs among this targeted group.

The role of coinfections in HIV epidemic trajectory and positive prevention: a systematic review and meta-analysis

OBJECTIVES

Recurrent or persistent coinfections may increase HIV viral load and, consequently, risk of HIV transmission, thus increasing HIV incidence. We evaluated the association between malaria, herpes simplex virus type 2 (HSV-2) and tuberculosis (TB) coinfections and their treatment on HIV viral load.

DESIGN

Systematic review and meta-analysis of the association of malaria, HSV-2 and TB coinfections and their treatment with HIV viral load.

METHODS

PubMed and Embase databases were searched to 10 February 2010 for studies in adults that reported HIV plasma and/or genital viral load by coinfection status or treatment. Meta-analyses were conducted using random-effects models.

RESULTS

Forty-five eligible articles were identified (six malaria, 20 HSV-2 and 19 TB). There was strong evidence of increased HIV viral load with acute malaria [0.67 log(10) copies/ml, 95% confidence interval (CI) 0.15-1.19] and decreased viral load following treatment (-0.37 log(10) copies/ml, 95% CI -0.70 to -0.04). Similarly, HSV-2 infection was associated with increased HIV viral load (0.18 log(10) copies/ml, 95% CI 0.01-0.34), which decreased with HSV suppressive therapy (-0.28 log(10) copies/ml, 95% CI -0.36 to -0.19). Active TB was associated with increased HIV viral load (0.40 log(10) copies/ml, 95% CI 0.13-0.67), but there was no association between TB treatment and viral load reduction (log(10) copies/ml -0.02, 95% CI -0.19 to 0.15).

CONCLUSION

Coinfections may increase HIV viral load in populations where they are prevalent, thereby facilitating HIV transmission. These effects may be reversed with treatment. However, to limit HIV trajectory and optimize positive prevention for HIV-infected individuals pre-antiretroviral therapy, we must better understand the mechanisms responsible for augmented viral load and the magnitude of viral load reduction required, and retune treatment regimens accordingly.

Left out but not forgotten: Should closer attention be paid to coinfection with herpes simplex virus type 1 and HIV?

Herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) are among the most common coinfections seen in individuals infected with HIV-1. Most research on HSV-HIV coinfection has focused on HSV-2, and in particular, on its impact on HIV transmission. HSV-2 is associated with micro- and macroulcerations in genital mucosal surfaces, increased numbers of HIV target cells in genital mucosal tissue and increases in plasma HIV viral load of up to 0.5 log(10) copies/mL, such that HSV-2 infection increases the risk of both HIV acquisition and transmission. Because plasma HIV RNA levels are a major determinant of rates of CD4 cell decline, HSV-2 coinfection may also adversely affect the progression of HIV disease. Anti-HSV medications have in fact been associated with reciprocal decreases in HIV viral load in short-term studies. These findings have led to the development of several clinical trials of HSV-2 suppression as strategies for preventing HIV transmission and slowing the rate of HIV disease progression. HSV-1 coinfection has largely been ignored from this growing body of research, yet there are several reasons that this coinfection remains an important issue for study. First, the seroprevalence of HSV-1 is consistently higher than that of HSV-2 among both HIV-infected and HIV-uninfected populations, underscoring the relevance of HSV-1 coinfection to the majority of HIV-infected persons. Second, pre-existing HSV-1 antibodies in individuals may modulate the course of subsequently acquired HSV-2 infection; the implications of such changes on HSV-HIV coinfection remain unexplored. Third, HSV-1 and HSV-2 are closely related viruses that share 83% genetic homology. Their virological and pathobiological similarities suggest that their implications on HIV pathogenesis may be similar as well. Finally, HSV-1 is becoming increasingly relevant because the incidence of genital HSV-1 has risen. Although genital herpes is traditionally associated with HSV-2, recent studies have shown that the majority of serologically confirmed primary genital herpes in some settings is attributable to HSV-1. Because the genital tract is an important site of biological interaction between HSV and HIV, this epidemiological change may be clinically important.