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PubMed2002

The antibody response to hepatitis B virus vaccination is negatively influenced by the hepatitis C virus viral load in patients with chronic hepatitis C: a case-control study.

The purpose of this work was to evaluate in a case-control study the immunogenicity of a recombinant hepatitis B virus (HBV) vaccine in patients with chronic hepatitis C. Seventy-seven patients with histologically proven chronic hepatitis C without cirrhosis were included in a prospective trial and matched for sex and age to 231 healthy adult subjects. Recombinant HBV vaccine was administered at a dose of 20 microg at months 0, 1 and 2. The definition of 'responder to vaccination' was anti-HBs titre > 10 mIU/ml after the three injections. Forty-nine (63.6%) chronic hepatitis C patients were responders to vaccination, compared with 217 (93.9%) controls (P < 0.0001). After the three injections, anti-HBs titres were 156 +/- 260 and 615 +/- 435 mIU/ml (P < 0.0001), respectively. Chronic hepatitis C patients who were non-responders to vaccination had significantly higher viral load than responders to vaccination. Moreover, a negative correlation was observed between viral load and anti-HBs concentration (r = -0.36, P = 0.003). No significant side effects were observed. There was no effect of vaccination on alanine aminotransferase (ALT) levels and hepatitis C virus (HCV) viral load during or after vaccination. In multivariate analysis, the main predictive factors of response to HBV vaccine were absence of anti-HCV antibodies (OR = 7.65, P < 0.0001), weight < 75 kg (OR = 1.99, P < 0.035), and age < 50 years (OR = 1.58, P < 0.082). Our results suggest that viral load seems to negatively influence the response to HBV vaccine.

Adult↗

PubMed2001

Epstein-Barr viral load measurement as a marker of EBV-related disease.

Epstein-Barr virus (EBV) is associated with a wide variety of benign and neoplastic diseases. EBV viral load assays that may prove useful in rapid assessment of disease status are now available. The two most common approaches to viral load measurement are quantitative, competitive PCR, and real-time PCR. Laboratory studies have shown that these assays are sensitive and specific for measuring EBV DNA in blood samples. Clinical investigations suggest a role for viral load measurement in predicting and monitoring EBV-associated tumors, including nasopharyngeal carcinoma, post-transplant lymphoproliferative disorder, Hodgkin's disease, and AIDS-related lymphoma. These new laboratory tools show promise in improving clinical management of affected patients.

Epstein-Barr Virus Infections↗

PubMed2005

Viral load of the human immunodeficiency virus could be an independent risk factor for endothelial dysfunction.

BACKGROUND: Recent reports of myocardial infarction in young persons infected with human immunodeficiency virus (HIV) who are receiving protease inhibitor therapy have raised concerns about premature coronary artery disease in this population. However, endothelial dysfunction, hypercoagulability, hypertriglyceridemia, and abnormal coronary artery pathology have been observed in association with HIV infection prior to the availability of protease inhibitor therapy. HYPOTHESIS: The study was undertaken to determine the association between endothelial function, viral load, CD4+ count, and other well-established risk factors for atherosclerosis. METHODS: This prospective, case-controlled study compared viral (HIV) load and the CD4+ T-lymphocyte count and endothelial function in 24 HIV-positive carriers. Brachial artery diameter, HIV viral load, and CD4 count were measured. RESULTS: We found that viral load correlated inversely with endothelial function; the higher the viral load, the worse the endothelial dysfunction (p < 0.005). CONCLUSION: High viral load appears to be associated with endothelial dysfunction in patients with HIV. This preliminary observation supports the infectious theory that viruses may play an important role in the pathogenesis of atherosclerosis.

Adult↗

PubMed2006

Viral load, organ distribution, histopathological lesions, and cytokine mRNA expression in goats infected with a molecular clone of the caprine arthritis encephalitis virus.

Caprine arthritis encephalitis virus (CAEV) is a lentivirus of goats that causes persistent infection characterized by the appearance of inflammatory lesions in various organs. To define the sites of persistence, 5 goats were infected with a molecular clone of CAEV, and the viral load was monitored by real-time-PCR and RT-PCR in different sites 8 years after infection. The lymph nodes proved to be an important virus reservoir, with moderate virus replication relative to what is reported for lentiviruses of primates. Mammary gland and milk cells were preferred sites of viral replication. The viral load varied significantly between animals, which points to an important role of the genetic background. We found a clear association between occurrence of histopathological lesions and viral load in specific sites. The mRNA expression analysis of several cytokines did not reveal differences between animals that could explain the considerable individual variations in viral load observed.

Animals↗

PubMed1998

Effects of vitamin E and C supplementation on oxidative stress and viral load in HIV-infected subjects.

OBJECTIVES: The HIV-infected population is known to be oxidatively stressed and deficient in antioxidant micronutrients. Since in vitro replication of HIV is increased with oxidative stress, this study assessed the effect of antioxidant vitamin supplementation on lipid peroxidation, a measure of oxidative stress, and viral load in humans. DESIGN: A randomized placebo-controlled, double-blind study. METHODS: Forty-nine HIV-positive patients were randomized to receive supplements of both DL-alpha-tocopherol acetate (800 IU daily) and vitamin C (1000 mg daily), or matched placebo, for 3 months. Plasma antioxidant micronutrient status, breath pentane output, plasma lipid peroxides, malondialdehyde and viral load were measured at baseline and at 3 months. New or recurrent infections for the 6-month period after study entry were also recorded. RESULTS: The vitamin group (n = 26) had an increase in plasma concentrations of alpha-tocopherol (P < 0.0005) and vitamin C (P < 0.005) and a reduction in lipid peroxidation measured by breath pentane (P < 0.025), plasma lipid peroxides (P < 0.01) and malondialdehyde (P < 0.0005) when compared with controls (n = 23). There was also a trend towards a reduction in viral load (mean +/- SD changes over 3 months, -0.45 +/- 0.39 versus +0.50 +/- 0.40 log10 copies/ml; P = 0.1; 95% confidence interval, -0.21 to -2.14). The number of infections reported was nine in the vitamin group and seven in the placebo group. CONCLUSION: Supplements of vitamin E and C reduce oxidative stress in HIV and produce a trend towards a reduction in viral load. This is worthy of larger clinical trials, especially in HIV-infected persons who cannot afford new combination therapies.

Adult↗

PubMed2004

High-dose interferon alpha-2b induction therapy in combination with ribavirin for Japanese patients infected with hepatitis C virus genotype 1b with a high baseline viral load.

BACKGROUND: Although pegylated interferon (IFN) is now used in many countries as a standard therapy for chronic hepatitis C, the efficacy and safety of combination therapy of high-dose interferon alpha-2b induction with ribavirin are not fully evaluated, especially in Japanese patients infected with hepatitis C virus (HCV) genotype 1b with a high viral load. METHODS: Patients ( n = 83) received daily, high-dose induction therapy of interferon alpha-2b (6 million units [MU] once daily for 2 weeks), followed by 6 MU three times weekly for 22 weeks. Oral ribavirin (800 or 600 mg/day) was given daily for 24 weeks, and then the patients were followed up for 24 weeks. RESULTS: Of the 83 patients, 67 (81%) had a biochemical response (BR), and 37 (45%) achieved a sustained BR (SBR). Virologic response (VR; undetectable serum HCV RNA level by polymerase chain reaction [PCR]) was noted in 55 (66%) patients, and sustained VR (SVR) in 16 (19%) patients. Baseline viral load did not influence treatment outcome. There was no significant difference in treatment outcome among treatment-naIve patients, relapsers, and nonresponders to previous IFN monotherapy. Multivariate analyses identified serum ribavirin concentrations at week 8 of therapy (odds ratio [OR], 23.7; 95% confidence interval [CI], 1.84-61.1; P = 0.015) and negativity for serum HCV RNA at week 8 (OR, 22.5; CI, 1.76-57.5; P = 0.017, respectively) as two significant and independent predictors of SVR. CONCLUSIONS: The efficacy of 24-week combination therapy of high-dose IFN alpha-2b induction and ribavirin deserves attention in HCV genotype 1b patients with a high viral load, especially in nonresponders to previous IFN monotherapy and patients with a very high viral load.

Adult↗

PubMed1999

Maternal viral load and vertical transmission of HIV-1 in mid-trimester gestation.

BACKGROUND: It is now accepted that the majority of HIV-1 vertical transmissions occur in late gestation and at the time of delivery. However, there is wide variation in the prevalence rate of mid-trimester vertical transmission. We assessed the maternal HIV-1 RNA viral load and in utero transmission during mid-trimester gestation. METHODS: Patients were enrolled when they decided to have their pregnancies terminated between 17 and 24 weeks of gestation. Prostaglandin-induced abortion with PGE1 analogue vaginal administration was carried out in all patients. Maternal plasma HIV-1 RNA viral load and plasma HIV-1 RNA (qualitative) from abortus heart blood were assessed. RESULTS: Amongst 41 HIV-1 seropositive pregnant women not receiving antiretroviral therapy plasma HIV-1 RNA was detected in the abortus heart blood from two women (4.9%; 95% confidence interval (CI), 0.6-16.5). Transmission occurred in one out of nine (11.1%; 95% CI, 0.3-48.2) with maternal viral load > or =100000 copies/ml versus one out of 32 (3.1%; 95% CI, 0.1-16.2) of those with <100000 copies/ml (P = 0.39). CONCLUSIONS: The frequency of HIV-1 vertical transmission during mid-trimester was approximately 5% as detected by plasma HIV-1 RNA (qualitative) method in the fetuses aborted from the prostaglandin termination of pregnancy. During mid-trimester gestation there was no correlation between high maternal viral load and vertical transmission.

Adult↗

PubMedDate not supplied

Interferon treatment for patients with chronic hepatitis C infected with high viral load of genotype 2 virus.

BACKGROUND/AIMS: Interferon treatment is more effective in patients with chronic hepatitis C infected with genotype 2a virus than those with genotype 1b virus. We analyzed patients with chronic hepatitis C treated by interferon in our clinics to develop a more effective regimen of interferon treatment for patients with genotype 2 virus infection. METHODOLOGY: We retrospectively analyzed the virological response of 36 patients with chronic hepatitis C with a high viral load, including 28 cases infected with the genotype 2a virus and 8 cases with the genotype 2b virus. The serum viral load of these patients were 6.0 log copies/mL and higher by the competitive polymerase chain reaction assay method. All patients could be treated with interferon-alpha or -beta for 6 months. Eleven patients were administered 6 million units of interferon-beta once daily for 6 weeks and then thrice weekly (group A). Twelve patients were administered 6 million units of interferon-alpha daily initially for 2 weeks and then thrice weekly (group B), and 10 patients were treated with the same dose of interferon-alpha thrice weekly from the first administration (group C). We decided the criteria of complete remission as the absence of serum HCV-RNA at both points of the end of interferon treatment and 6 months later. RESULTS: For all patients with genotype 2a virus infection, the complete remission, transient response and no response rates were 46.4%, 39.3% and 14.3%, respectively. The complete remission rates in group A, B and C were 100%, 41.7% and 20%, respectively. The transient remission rates in group B and C were 41.7% and 60%, respectively. The no response rates in group B and C were 16.7% and 20%, respectively. All patients with a high viral load of genotype 2a virus showed eradicated serum HCV-RNA virus in group A. The eradication rate of serum HCV-RNA in patients infected with the genotype 2a virus in group A was significantly higher than that of group B (p < 0.02) or group C (p < 0.01). For all patients with genotype 2b virus infection, complete remission, transient remission and no response rates were 12.5%, 50.0% and 37.5%, respectively. The complete remission rate of patients with the genotype 2b virus in group A and group B plus C was 0% and 25.0%, respectively. The eradication rate of patients with the genotype 2a virus in group A was significantly higher than that of patients with the genotype 2b virus (p < 0.01). CONCLUSIONS: These findings suggest that the initial sufficient dose of interferon administration is effective to eradicate serum HCV-RNA in patients with a high viral load of genotype 2a virus in chronic hepatitis C.

Adult↗

PubMed1998

Mathematical modeling of the interrelationship of CD4 lymphocyte count and viral load changes induced by the protease inhibitor indinavir.

While CD4 cell counts are widely used to predict disease progression in human immunodeficiency virus (HIV)-infected patients, they are poorly explanatory of the progression to AIDS or death after the introduction of chemotherapy. Changes in HIV load (as measured by RNA PCR) have been shown to be a much better predictor of the risk of disease progression. Since the interrelationship of these markers is of great clinical interest, we modeled the time-averaged return of CD4 cell count and change in viral load subsequent to therapy with the HIV protease inhibitor indinavir. We found that CD4 cell return was significantly related to both the baseline CD4 count (r2 = 0.86, P < 0.001) and the decline in HIV RNA PCR-determined viral load (also referred to in this work as the HIV RNA PCR decline) (r2 = 0.60, P < 0.01). Simultaneously modeling both influences in a linked nonlinear model (r2 = 0.93, P < 0.001) demonstrated that (i) the starting number of CD4 cells accounted for the majority of the change in CD4 cell return and (ii) the return of CD4 cells attributable to viral load decrease was 50% of maximal with only a decrease of approximately 0.2 log of HIV RNA as modeled from the first 12 weeks of therapy. Much greater viral inhibition beyond that necessary for maximal CD4 cell return is possible. Given that HIV RNA PCR decline is more strongly linked to ultimate clinical course in HIV disease, our findings indicate that CD4 return is potentially misleading as an indicator of antiviral effect, since it is determined more by the starting CD4 value than by viral load decline and since near-maximal changes occur with minimal antiviral effect.

Acquired Immunodeficiency Syndrome↗

PubMed2001

Influence of a partner's HIV serostatus, use of highly active antiretroviral therapy, and viral load on perceptions of sexual risk behavior in a community sample of men who have sex with men.

OBJECTIVE: To assess the perceptions of gay and bisexual men concerning the risk of HIV transmission through various sexual practices with a new sex partner depending on that partner's disclosed HIV status, antiretroviral treatment status, and viral load. METHODS: Study participants read four different scenarios describing sexual situations with a new partner and rated each scenario for risk of HIV transmission. HIV status and antiretroviral treatment status disclosed by the new sex partner were varied across four scenarios: unknown HIV status; HIV-negative; HIV-positive and not taking highly active antiretroviral therapy (HAART); and HIV-positive and taking HAART with an undetectable viral load. RESULTS: Study participants were 472 men attending a gay pride festival who reported that they were HIV-negative. Eighty-nine percent of the men were white, and the mean age of the study participants was 35.8 years. Of the four scenarios, sex with an HIV-positive partner not taking HAART was rated as posing the greatest risk. Sex with an HIV-positive partner taking HAART who had an undetectable viral load was not consistently viewed as riskier than sex with an HIV-negative partner or a man with an unknown HIV status. CONCLUSIONS: The current study provides preliminary evidence for the effect of disclosure of HIV serostatus, use of HAART, and the presence of an undetectable viral load on the perceptions of sexual risk for HIV-negative men. The findings suggest that some gay and bisexual men judge risk based on the perceived HIV status of their sex partners and not on the general assumption that all sex partners entail equal risk, as many prevention campaigns have emphasized.

Adult↗

PubMed2003

Low CD4+ T-cell count and high HIV viral load precede the development of tuberculosis disease in a cohort of HIV-positive Ethiopians.

SETTING: Prospective cohort study, Ethiopia. OBJECTIVE: To study changes in biological markers of HIV infection progression before and after development of TB disease. DESIGN: A longitudinal study of 804 adult factory workers (95 HIV-positive, 709 HIV-negative), who were followed every 6 months for a median of 3.8 years. RESULTS: Overall, the incidence rate of TB was 10/222 = 45.1 (95%CI 24.3-83.9) per 1000 person-years of observation (PYO) among HIV-1-positive participants, compared to 14/2054 = 6.8 (95%CI 4.0-11.5) per 1000 PYO among HIV-1-negative participants (incidence rate ratio 6.62, 95%CI 2.94-14.9). Among the 10 HIV-positive participants who subsequently developed TB disease, the CD4 count was low (median 201/microliter, range 45-419), and viral load high (median 4.97 log copies/ml, range 3.70-5.58), at the routine follow-up visit prior to TB diagnosis. Following TB treatment, plasma viral load remained persistently elevated despite clinical resolution of TB disease, and seven of the 10 patients died within a median time of 8 months. CONCLUSION: In this cohort, HIV-infected Ethiopians who developed TB disease already had low CD4 counts and high viral load prior to the diagnosis of TB. Viral load did not decrease following TB treatment, leading to a poor overall prognosis in these patients.

AIDS-Related Opportunistic Infections↗

PubMed1999

Maternal viral load and timing of mother-to-child HIV transmission, Bangkok, Thailand. Bangkok Collaborative Perinatal HIV Transmission Study Group.

OBJECTIVES: To determine the proportion of HIV-1-infected infants infected in utero and intrapartum, the relationship between transmission risk factors and time of transmission, and the population-attributable fractions for maternal viral load. DESIGN: Prospective cohort study of 218 formula-fed infants of HIV-1-infected untreated mothers with known infection outcome and a birth HIV-1-positive DNA PCR test result. METHODS: Transmission in utero was presumed to have occurred if the birth sample (within 72 h of birth) was HIV-1-positive by PCR; intrapartum transmission was presumed if the birth sample tested negative and a later sample was HIV-1-positive. Two comparisons were carried out for selected risk factors for mother-to-child transmission: infants infected in utero versus all infants with a HIV-1-negative birth PCR test result, and infants infected intrapartum versus uninfected infants. RESULTS: Of 49 infected infants with an HIV-1 birth PCR result, 12 (24.5%) [95% confidence interval (CI), 14 -38] were presumed to have been infected in utero and 37 (75.5%) were presumed to have been infected intrapartum. The estimated absolute overall transmission rate was 22.5%; this comprised 5.5% (95% CI, 3-9) in utero transmission and 18% (95% CI, 13-24) intrapartum transmission. Intrapartum transmission accounted for 75.5% of infections. High maternal HIV-1 viral load (> median) was a strong risk factor for both in utero [adjusted odds ratio (AOR) 5.8 (95% CI, 1.4-38.8] and intrapartum transmission (AOR, 4.4; 95% CI, 1.9-11.2). Low birth-weight was associated with in utero transmission, whereas low maternal natural killer cell and CD4(+) T-lymphocyte percentages were associated with intrapartum transmission. The population-attributable fraction for intrapartum transmission associated with viral load > 10 000 copies/ml was 69%. CONCLUSIONS: Our results provide further evidence that most perinatal HIV-1 transmission occurs during labor and delivery, and that risk factors may differ according to time of transmission. Interventions to reduce maternal viral load should be effective in reducing both in utero and intrapartum transmission.

Cohort Studies↗

PubMed2003

Low CD4+ T-cell count and high HIV viral load precede the development of tuberculosis disease in a cohort of HIV-positive ethiopians.

SETTING: Prospective cohort study, Ethiopia. OBJECTIVE: To study changes in biological markers of HIV infection progression before and after development of TB disease. DESIGN: A longitudinal study of 804 adult factory workers (95 HIV-positive, 709 HIV-negative), who were followed every 6 months for a median of 3.8 years. RESULTS: Overall, the incidence rate of TB was 10/ 222 = 45.1 (95%CI 24.3-83.9) per 1000 person-years of observation (PYO) among HIV-1-positive participants, compared to 14/2,054 = 6.8 (95%CI 4.0-11.5) per 1,000 PYO among HIV-1-negative participants (incidence rate ratio 6.62, 95%CI 2.94-14.9). Among the 10 HIV-positive participants who subsequently developed TB disease, the CD4 count was low (median 201/microl, range 45-419), and viral load high (median 4.97 log copies/ml, range 3.70-5.58), at the routine follow-up visit prior to TB diagnosis. Following TB treatment, plasma viral load remained persistently elevated despite clinical resolution of TB disease, and seven of the 10 patients died within a median time of 8 months. CONCLUSION: In this cohort, HIV-infected Ethiopians who developed TB disease already had low CD4 counts and high viral load prior to the diagnosis of TB. Viral load did not decrease following TB treatment, leading to a poor overall prognosis in these patients.

Adult↗

PubMed2000

Viral load trend in HIV-1 seropositive patients with different CD4 cell counts before starting HAART.

BACKGROUND: The efficacy of highly active antiretroviral therapy (HAART) was prospectively monitored in HIV-1 seropositive patients by analyzing HIV-1 RNA viral load. OBJECTIVES: The aim of the study was to evaluate the viral load course in two different groups of patients (group 1: CD4>400/mm(3), group 2: CD4<200/mm(3)) during a period ranging from 9 to 25 months. STUDY DESIGN: HIV-1 viral load, at the start and during HAART, was analyzed in 117 patients who had previously been treated only with two anti-transcriptase drugs but were naive for protease inhibitors. RESULTS: The results showed that, after the beginning of therapy, high plasma HIV-1 RNA levels dropped to undetectable values (<50 copies HIV-RNA/ml) in one third of patients over a mean period of about 9 months irrespective of the initial CD4 cell count, even though a viral reduction of at least 2log(s) in a significantly shorter period of time (P<0.001) was observed only among patients who began retroviral therapy with a higher CD4 cell count. CONCLUSION: The response to HAART was not dramatically affected by the initial CD4 count. Though restricted to a small number of subjects, the data support the idea that therapeutic intervention can be effective even in an advanced stage of HIV-1 infection, when patients show a decreased number of CD4 T-lymphocytes.

Anti-HIV Agents↗

PubMed2003

Viral load as a predictor of the risk of cervical intraepithelial neoplasia.

HPV infections are believed to be a necessary cause of cervical cancer. Viral burden, as a surrogate indicator for persistence, may help predict risk of subsequent SIL. We used results of HPV test and cytology data repeated every 4-6 months in 2,081 women participating in a longitudinal study of the natural history of HPV infection and cervical neoplasia in São Paulo, Brazil. Using the MY09/11 PCR protocol, 473 women were positive for HPV DNA during the first 2 visits. We retested all positive specimens by a quantitative, low-stringency PCR method to measure viral burden in cervical cells. Mean viral loads and 95% CIs were calculated using log-transformed data. RRs and 95% CIs of incident SIL were calculated by proportional hazards models, adjusting for age and HPV oncogenicity. The risk of incident lesions increased with viral load at enrollment. The mean number of viral copies/cell at enrollment was 2.6 for women with no incident lesions and increased (trend p = 0.003) to 15.1 for women developing 3 or more SIL events over 6 years of follow-up. Compared to those with <1 copy per cell in specimens tested during the first 2 visits, RRs for incident SIL increased from 1.9 (95% CI 0.8-4.2) for those with 1-10 copies/cell to 4.5 (95% CI 1.9-10.7) for those with >1,000 copies/cell. The equivalent RR of HSIL for >1,000 copies/cell was 2.6 (95% CI 0.5-13.2). Viral burden appears to have an independent effect on SIL incidence. Measurement of viral load, as a surrogate for HPV persistence, may identify women at risk of developing cervical cancer precursors.

Adolescent↗

PubMed2005

Parvovirus B19 viral loads in relation to VP1 and VP2 antibody responses in diagnostic blood samples.

BACKGROUND: Human parvovirus B19 infection is characterised by high peak viral load levels followed by episodes of prolonged viremia. The risk of transmission of parvovirus B19 by blood or blood products has been increasingly recognised and parameters that can predict the risk of transmission are subject of interest. OBJECTIVES: This study aimed to study correlations between B19 viral DNA loads and antibody responses to the viral antigens VP1 and VP2 in clinical serum samples. STUDY DESIGN: A panel of 1610 serum samples from patients clinically suspected from acute B19 infection were analysed. Antibodies were measured by the parvovirus anti-VP1 immuno-fluorescence assay (IFA) and the anti-VP2 enzyme immunoassay (EIA) from Biotrin. B19 viral loads were measured by a real-time PCR using the external WHO standard for DNA quantification. RESULTS: Positive IgM responses were found in 154 (9.6%) of the 1610 sera tested. Based on the PCR results in a subset of 312 sera, the anti-VP2 EIA IgM showed a better combination of sensitivity/specificity (91%/94%) compared to the anti-VP1 IFA (66%/97%). B19 DNA levels in the sera strongly correlated with the levels of IgM antibodies, all sera with high viral loads (>10(6)IU/ml) having VP2 EIA IgM ratios above 3.0. CONCLUSIONS: The B19 VP2 IgM ELISA is superior to the B19 VP1 IgM IFA if verified by PCR. Anti-VP2 IgM antibodies in sera are indicative for the presence B19 DNA and can be used to predict high levels of B19 DNA in diagnostic sera.

Adolescent↗

PubMed1998

A genetic and viral load analysis of the simian immunodeficiency virus during the acute phase in macaques inoculated by the vaginal route.

A comparative genetic analysis of SIV-infected female macaques during the first 120 days postinfection was undertaken. The same dose of a macaque-passaged SIVmac239(nef open) was administered to three macaques intravenously (i.v.) and to three macaques intravaginally (i.VAG). Clinical outcomes observed ranged from rapid to nonprogression, while two of the i.v.-infected macaques developed an uncommon hindleg paresis. Analysis of viral load (bDNA assay) determined that both i.v.- and i.VAG-infected macaques had comparable high viral loads at the observed viral peak of 14 days postinfection. A study of viral quasispecies diversity by the heteroduplex mobility assay indicated that (1) the i.v.-infected macaques had a highly heterogeneous quasispecies population similar to the infecting viral stock; and (2) in two of three i.VAG-infected macaques multiple viral genotypes (minimum, three or four) were observed in blood and lymph tissues at early times postinfection, which indicated that limited numbers of viral variants crossed the vaginal mucosa and established infection. Therefore, the route of infection can clearly influence early viral selection and diversity. In addition, a third i.VAG-infected macaque, which was a rapid progressor, did not seroconvert and progressed to AIDS in 120 days. This macaque exhibited a high viral load and heterogeneous quasispecies. These data demonstrate differences in the quasispecies complexity associated with route of infection and rate of disease progression.

Amino Acid Sequence↗

PubMed2005

A randomized trial of the efficacy of group therapy in changing viral load and CD4 counts in individuals living with HIV infection.

OBJECTIVE: This randomized pilot study evaluates whether seropositive patients who are randomly assigned to receive a supportive-expressive group therapy plus education intervention show greater improvements in increased immune function and decreased viral load compared to those randomly assigned to an education-only intervention. METHOD: Fifty-nine individuals who had been HIV-seropositive for at least 6 months prior to inclusion in the study and had been receiving standard pharmacologic treatment were entered in a prospective randomized trial of the effects of weekly supportive-expressive group therapy on changes in immune status. Participants were matched for AIDS status and sex and randomized to receive weekly sessions of group psychotherapy plus educational materials on HIV/AIDS, or to receive the educational materials alone. Participants were assessed before treatment and then 12 weeks later. RESULTS: Individuals who were randomized to group therapy showed a statistically significant increase in CD4 count and decrease in HIV viral load. Among individuals randomized to the education only condition, no significant change occurred in CD4 count or viral load. CONCLUSIONS: These results provide preliminary data suggesting that HIV-seropositive individuals who receive supportive-expressive group psychotherapy may experience concomitant improvements in CD4 cell count and viral load. Further research with a larger sample should examine the possible underlying mechanisms of such benefits.

Adult↗