Displaying publications 1 - 20 of 103 in total

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  1. Bartlett AW, Lumbiganon P, Jamal Mohamed TA, Lapphra K, Muktiarti D, Du QT, et al.
    J. Acquir. Immune Defic. Syndr., 2019 Dec 15;82(5):431-438.
    PMID: 31714422 DOI: 10.1097/QAI.0000000000002184
    BACKGROUND: Perinatally HIV-infected adolescents (PHIVA) are an expanding population vulnerable to loss to follow-up (LTFU). Understanding the epidemiology and factors for LTFU is complicated by varying LTFU definitions.

    SETTING: Asian regional cohort incorporating 16 pediatric HIV services across 6 countries.

    METHODS: Data from PHIVA (aged 10-19 years) who received combination antiretroviral therapy 2007-2016 were used to analyze LTFU through (1) an International epidemiology Databases to Evaluate AIDS (IeDEA) method that determined LTFU as >90 days late for an estimated next scheduled appointment without returning to care and (2) the absence of patient-level data for >365 days before the last data transfer from clinic sites. Descriptive analyses and competing-risk survival and regression analyses were used to evaluate LTFU epidemiology and associated factors when analyzed using each method.

    RESULTS: Of 3509 included PHIVA, 275 (7.8%) met IeDEA and 149 (4.3%) met 365-day absence LTFU criteria. Cumulative incidence of LTFU was 19.9% and 11.8% using IeDEA and 365-day absence criteria, respectively. Risk factors for LTFU across both criteria included the following: age at combination antiretroviral therapy initiation <5 years compared with age ≥5 years, rural clinic settings compared with urban clinic settings, and high viral loads compared with undetectable viral loads. Age 10-14 years compared with age 15-19 years was another risk factor identified using 365-day absence criteria but not IeDEA LTFU criteria.

    CONCLUSIONS: Between 12% and 20% of PHIVA were determined LTFU with treatment fatigue and rural treatment settings consistent risk factors. Better tracking of adolescents is required to provide a definitive understanding of LTFU and optimize evidence-based models of care.

    Matched MeSH terms: Viral Load
  2. Elvert M, Sauerhering L, Maisner A
    J. Infect. Dis., 2019 Oct 30.
    PMID: 31665348 DOI: 10.1093/infdis/jiz455
    During the Nipah virus (NiV) outbreak in Malaysia, pigs and humans were infected. While pigs generally developed severe respiratory disease due to an effective virus replication and associated inflammation processes in the porcine airways, respiratory symptoms in humans were rare and less severe. To elucidate the reasons for the species-specific differences in NiV airway infections, we compared the cytokine responses as a first reaction to NiV in primary porcine and human bronchial epithelial cells (PBEpC and HBEpC, respectively). In both cell types, NiV infections resulted in the expression of type III interferons (IFN-λ). Upon infections with similar virus doses, the viral RNA load and IFN expression were substantially higher in HBEpC. Even if PBEpC expressed the same viral RNA amounts as NiV-infected HBEpC, the porcine cells showed a reduced IFN- and IFN-dependent antiviral gene expression. Despite this inherently limited IFN response, the expression of proinflammatory cytokines (IL-6, IL-8) in NiV-infected PBEpC was not decreased. The downregulation of the antiviral activity in the presence of a functional proinflammatory cytokine response might be one of the species-specific factors contributing to efficient virus replication and acute inflammation in the lungs of pigs infected with the Malaysian NiV strain.
    Matched MeSH terms: Viral Load
  3. Mohd A, Zainal N, Tan KK, AbuBakar S
    Sci Rep, 2019 Oct 04;9(1):14336.
    PMID: 31586088 DOI: 10.1038/s41598-019-50674-3
    Zika virus (ZIKV) infection is a serious public health concern. ZIKV infection has been associated with increased occurrences of microcephaly among newborns and incidences of Guillain-Barré syndrome among adults. No specific therapeutics or vaccines are currently available to treat and protect against ZIKV infection. Here, a plant-secreted phytoalexin, resveratrol (RES), was investigated for its ability to inhibit ZIKV replication in vitro. Several RES treatment regimens were used. The ZIKV titers of mock- and RES-treated infected cell cultures were determined using the focus-forming assay and the Zika mRNA copy number as determined using qRT-PCR. Our results suggested that RES treatment reduced ZIKV titers in a dose-dependent manner. A reduction of >90% of virus titer and ZIKV mRNA copy number was achieved when infected cells were treated with 80 µM of RES post-infection. Pre-incubation of the virus with 80 µM RES showed >30% reduction in ZIKV titers and ZIKV mRNA copy number, implying potential direct virucidal effects of RES against the virus. The RES treatment reduced >70% virus titer in the anti-adsorption assay, suggesting the possibility that RES also interferes with ZIKV binding. However, there was no significant decrease in ZIKV titer when a short-period of RES treatment was applied to cells before ZIKV infection (pre-infection) and after the virus bound to the cells (virus internalization inhibition), implying that RES acts through its continuous presence in the cell cultures after virus infection. Overall, our results suggested that RES exhibited direct virucidal activity against ZIKV and possessed anti-ZIKV replication properties, highlighting the need for further exploration of RES as a potential antiviral molecule against ZIKV infection.
    Matched MeSH terms: Viral Load
  4. Wan Yusuf WN, Wan Mohammad WMZ, Gan SH, Mustafa M, Abd Aziz CB, Sulaiman SA
    J Tradit Complement Med, 2019 Oct;9(4):249-256.
    PMID: 31453119 DOI: 10.1016/j.jtcme.2018.05.003
    This is the first study to report on the effects of honey in asymptomatic HIV positive subjects in ameliorating CD4 count, viral load (VL) and quality of life (QOL). It is a randomized, controlled, open labelled study, comparing the effects of Tualang honey (TH) administration for six months at three different doses: 20 g (THL), 40 g (THI) or 60 g (THH) daily compared with control (no administered treatment, THC). Only asymptomatic HIV positive subjects (n=95) having CD4 count 250-600 cell/ml, not on antiretrovirals were enrolled. Blood, (together with QOL questionnaires administration) were investigated at baseline, three and six months (CD4 cell count) while VL was determined only at baseline and six months. Significant reductions in CD4 counts in THL and THC groups (p= 0.003 for both) were seen with no significant reductions in the CD4 counts in THI and THH groups (p=0.447 and 0.053 respectively). There was improvement in VL in THC and THI (130% and 32% respectively) and reductions in THL and THH (26% and 8% respectively). Within and between group analyses for VL indicated significant differences between THL and THH compared to THC. In addition, significant improvement in QOL of groups which received TH was noted. TH has the potential to improve the QOL (physical and psychological) and CD4 counts. There was a trend of lower VL in asymptomatic HIV subjects following TH administration thus supporting the possible role of TH in boosting the immune system by improving CD4 counts, causing VL reductions in HIV positive subjects.
    Matched MeSH terms: Viral Load
  5. Mohamed Amin Z, Che Ani MA, Tan SW, Yeap SK, Alitheen NB, Syed Najmuddin SUF, et al.
    Sci Rep, 2019 Sep 30;9(1):13999.
    PMID: 31570732 DOI: 10.1038/s41598-019-50222-z
    The Newcastle disease virus (NDV) strain AF2240 is an avian avulavirus that has been demonstrated to possess oncolytic activity against cancer cells. However, to illicit a greater anti-cancer immune response, it is believed that the incorporation of immunostimulatory genes such as IL12 into a recombinant NDV backbone will enhance its oncolytic effect. In this study, a newly developed recombinant NDV that expresses IL12 (rAF-IL12) was tested for its safety, stability and cytotoxicity. The stability of rAF-IL12 was maintained when passaged in specific pathogen free (SPF) chicken eggs from passage 1 to passage 10; with an HA titer of 29. Based on the results obtained from the MTT cytotoxic assay, rAF-IL12 was determined to be safe as it only induced cytotoxic effects against normal chicken cell lines and human breast cancer cells while sparing normal cells. Significant tumor growth inhibition (52%) was observed in the rAF-IL12-treated mice. The in vivo safety profile of rAF-IL12 was confirmed through histological observation and viral load titer assay. The concentration and presence of the expressed IL12 was quantified and verified via ELISA assay. In summary, rAF-IL12 was proven to be safe, selectively replicating in chicken and cancer cells and was able to maintain its stability throughout several passages; thus enhancing its potential as an anti-breast cancer vaccine.
    Matched MeSH terms: Viral Load
  6. Bartlett AW, Lumbiganon P, Kurniati N, Sudjaritruk T, Mohamed TJ, Hansudewechakul R, et al.
    J Adolesc Health, 2019 Aug 05.
    PMID: 31395514 DOI: 10.1016/j.jadohealth.2019.05.025
    PURPOSE: Antiretroviral monotherapy and treatment interruption are potential strategies for perinatally HIV-infected adolescents (PHIVA) who face challenges maintaining effective combination antiretroviral therapy (ART). We assessed the use and outcomes for adolescents receiving monotherapy or undergoing treatment interruption in a regional Asian cohort.

    METHODS: Regional Asian data (2001-2016) were analyzed to describe PHIVA who experienced ≥2 weeks of lamivudine or emtricitabine monotherapy or treatment interruption and trends in CD4 count and HIV viral load during and after episodes. Survival analyses were used for World Health Organization (WHO) stage III/IV clinical and immunologic event-free survival during monotherapy or treatment interruption, and a Poisson regression to determine factors associated with monotherapy or treatment interruption.

    RESULTS: Of 3,448 PHIVA, 84 (2.4%) experienced 94 monotherapy episodes, and 147 (4.3%) experienced 174 treatment interruptions. Monotherapy was associated with older age, HIV RNA >400 copies/mL, younger age at ART initiation, and exposure to ≥2 combination ART regimens. Treatment interruption was associated with CD4 count <350 cells/μL, HIV RNA ≥1,000 copies/mL, ART adverse event, and commencing ART age ≥10 years compared with age <3 years. WHO clinical stage III/IV 1-year event-free survival was 96% and 85% for monotherapy and treatment interruption cohorts, respectively. WHO immunologic stage III/IV 1-year event-free survival was 52% for both cohorts. Those who experienced monotherapy or treatment interruption for more than 6 months had worse immunologic and virologic outcomes.

    CONCLUSIONS: Until challenges of treatment adherence, engagement in care, and combination ART durability/tolerability are met, monotherapy and treatment interruption will lead to poor long-term outcomes.

    Matched MeSH terms: Viral Load
  7. Zhang L, Tao Y, Woodring J, Rattana K, Sovannarith S, Rathavy T, et al.
    Int J Epidemiol, 2019 Aug 01;48(4):1327-1339.
    PMID: 30879066 DOI: 10.1093/ije/dyz037
    BACKGROUND: The Regional Framework for Triple Elimination of Mother-to-Child Transmission (EMTCT) of HIV, Hepatitis B (HBV) and Syphilis in Asia and the Pacific 2018-30 was endorsed by the Regional Committee of WHO Western Pacific in October 2017, proposing an integrated and coordinated approach to achieve elimination in an efficient, coordinated and sustainable manner. This study aims to assess the population impacts and cost-effectiveness of this integrated approach in the Cambodian context.

    METHODS: Based on existing frameworks for the EMTCT for each individual infection, an integrated framework that combines infection prevention procedures with routine antenatal care was constructed. Using decision tree analyses, population impacts, cost-effectiveness and the potential reduction in required resources of the integrated approach as a result of resource pooling and improvements in service coverage and coordination, were evaluated. The tool was assessed using simulated epidemiological data from Cambodia.

    RESULTS: The current prevention programme for 370,000 Cambodian pregnant women was estimated at USD$2.3 ($2.0-$2.5) million per year, including the duration of pregnancy and up to 18 months after delivery. A model estimate of current MTCT rates in Cambodia was 6.6% (6.2-7.1%) for HIV, 14.1% (13.1-15.2%) for HBV and 9.4% (9.0-9.8%) for syphilis. Integrating HIV and syphilis prevention into the existing antenatal care framework will reduce the total time required to provide this integrated care by 19% for health care workers and by 32% for pregnant women, resulting in a net saving of $380,000 per year for the EMTCT programme. This integrated approach reduces HIV and HBV MTCT to 6.1% (5.7-6.5%) and 13.0% (12.1-14.0%), respectively, and substantially reduces syphilis MCTC to 4.6% (4.3-5.0%). Further introduction of either antiviral treatment for pregnant women with high viral load of HBV, or hepatitis B immunoglobulin (HBIG) to exposed newborns, will increase the total cost of EMTCT to $4.4 ($3.6-$5.2) million and $3.3 ($2.7-$4.0) million per year, respectively, but substantially reduce HBV MTCT to 3.5% (3.2-3.8%) and 5.0% (4.6-5.5%), respectively. Combining both antiviral and HBIG treatments will further reduce HBV MTCT to 3.4% (3.1-3.7%) at an increased total cost of EMTCT of $4.5 ($3.7-$5.4) million per year. All these HBV intervention scenarios are highly cost-effective ($64-$114 per disability-adjusted life years averted) when the life benefits of these prevention measures are considered.

    CONCLUSIONS: The integrated approach, using antenatal, perinatal and postnatal care as a platform in Cambodia for triple EMTCT of HIV, HBV and syphilis, is highly cost-effective and efficient.

    Matched MeSH terms: Viral Load
  8. Mire CE, Geisbert JB, Agans KN, Versteeg KM, Deer DJ, Satterfield BA, et al.
    Emerging Infect. Dis., 2019 06;25(6):1144-1152.
    PMID: 31107231 DOI: 10.3201/eid2506.181620
    Nipah virus (NiV) is a zoonotic pathogen that causes high case-fatality rates (CFRs) in humans. Two NiV strains have caused outbreaks: the Malaysia strain (NiVM), discovered in 1998-1999 in Malaysia and Singapore (≈40% CFR); and the Bangladesh strain (NiVB), discovered in Bangladesh and India in 2001 (≈80% CFR). Recently, NiVB in African green monkeys resulted in a more severe and lethal disease than NiVM. No NiV vaccines or treatments are licensed for human use. We assessed replication-restricted single-injection recombinant vesicular stomatitis vaccine NiV vaccine vectors expressing the NiV glycoproteins against NiVB challenge in African green monkeys. All vaccinated animals survived to the study endpoint without signs of NiV disease; all showed development of NiV F Ig, NiV G IgG, or both, as well as neutralizing antibody titers. These data show protective efficacy against a stringent and relevant NiVB model of human infection.
    Matched MeSH terms: Viral Load
  9. Rich KM, Wickersham JA, Valencia Huamaní J, Kiani SN, Cabello R, Elish P, et al.
    LGBT Health, 2019 3 16;5(8):477-483.
    PMID: 30874476 DOI: 10.1089/lgbt.2017.0186
    PURPOSE: Globally, transgender women (TGW) experience a high burden of adverse health outcomes, including a high prevalence of HIV and sexually transmitted infections (STIs) as well as psychiatric disorders and substance use disorders. To address gaps in HIV research in Peru focused specifically on TGW, this study presents characteristics of a sample of HIV-positive TGW and identifies factors associated with viral suppression.

    METHODS: Between June 2015 and August 2016, 50 HIV-positive TGW were recruited in Lima, Peru. Multivariable logistic regression was used to identify factors associated with viral suppression (<200 copies/mL) among the TGW.

    RESULTS: Among TGW, 85% achieved viral suppression. Approximately half (54%) reported anal sex with more than five partners in the past 6 months, 38% reported sex work, 68% had not disclosed their HIV status to one or more of their partners, and 38% reported condomless sex with their last partner. The prevalence of alcohol use disorders was high (54%), and 38% reported use of drugs in the past year. Moderate-to-severe drug use significantly reduced odds of achieving viral suppression (adjusted odds ratio 0.69; 95% confidence interval: 0.48-0.98).

    CONCLUSION: Our findings highlight the need for integrated treatment for substance disorders in HIV care to increase the viral suppression rate among TGW in Lima, Peru.

    Matched MeSH terms: Viral Load/statistics & numerical data*
  10. Bartlett AW, Mohamed TJ, Sudjaritruk T, Kurniati N, Nallusamy R, Hansudewechakul R, et al.
    Pediatr. Infect. Dis. J., 2019 03;38(3):287-292.
    PMID: 30281549 DOI: 10.1097/INF.0000000000002208
    BACKGROUND: Perinatally HIV-infected adolescents (PHIVA) are exposed to a chronic systemic infection and long-term antiretroviral therapy (ART), leaving them susceptible to morbidities associated with inflammation, immunodeficiency and drug toxicity.

    METHODS: Data collected 2001 to 2016 from PHIVA 10-19 years of age within a regional Asian cohort were analyzed using competing risk time-to-event and Poisson regression analyses to describe the nature and incidence of morbidity events and hospitalizations and identify factors associated with disease-related, treatment-related and overall morbidity. Morbidity was defined according to World Health Organization clinical staging criteria and U.S. National Institutes of Health Division of AIDS criteria.

    RESULTS: A total 3,448 PHIVA contributed 17,778 person-years. Median age at HIV diagnosis was 5.5 years, and ART initiation was 6.9 years. There were 2,562 morbidity events and 307 hospitalizations. Cumulative incidence for any morbidity was 51.7%, and hospitalization was 10.0%. Early adolescence was dominated by disease-related infectious morbidity, with a trend toward noninfectious and treatment-related morbidity in later adolescence. Higher overall morbidity rates were associated with a CD4 count <350 cells/µL, HIV viral load ≥10,000 copies/mL and experiencing prior morbidity at age <10 years. Lower overall morbidity rates were found for those 15-19 years of age compared with 10-14 years and those who initiated ART at age 5-9 years compared with <5 or ≥10 years.

    CONCLUSIONS: Half of our PHIVA cohort experienced a morbidity event, with a trend from disease-related infectious events to treatment-related and noninfectious events as PHIVA age. ART initiation to prevent immune system damage, optimize virologic control and minimize childhood morbidity are key to limiting adolescent morbidity.

    Matched MeSH terms: Viral Load
  11. Mu W, Bartlett AW, Bunupuradah T, Chokephaibulkit K, Kumarasamy N, Ly PS, et al.
    J. Acquir. Immune Defic. Syndr., 2019 03 01;80(3):308-315.
    PMID: 30531299 DOI: 10.1097/QAI.0000000000001921
    BACKGROUND: Virologic failure is a major threat to maintaining effective combination antiretroviral therapy, especially for children in need of lifelong treatment. With efforts to expand access to HIV viral load testing, our understanding of pediatric virologic failure is evolving.

    SETTING: An Asian cohort in 16 pediatric HIV services across 6 countries.

    METHODS: From 2005 to 2014, patients younger than 20 years who achieved virologic suppression and had subsequent viral load testing were included. Early virologic failure was defined as a HIV RNA ≥1000 copies per milliliter within 12 months of virologic suppression, and late virologic as a HIV RNA ≥1000 copies per milliliter after 12 months following virologic suppression. Characteristics at combination antiretroviral therapy initiation and virologic suppression were described, and a competing risk time-to-event analysis was used to determine cumulative incidence of virologic failure and factors at virologic suppression associated with early and late virologic failure.

    RESULTS: Of 1105 included in the analysis, 182 (17.9%) experienced virologic failure. The median age at virologic suppression was 6.9 years, and the median time to virologic failure was 24.6 months after virologic suppression. The incidence rate for a first virologic failure event was 3.3 per 100 person-years. Factors at virologic suppression associated with late virologic failure included older age, mostly rural clinic setting, tuberculosis, protease inhibitor-based regimens, and early virologic failure. No risk factors were identified for early virologic failure.

    CONCLUSIONS: Around 1 in 5 experienced virologic failure in our cohort after achieving virologic suppression. Targeted interventions to manage complex treatment scenarios, including adolescents, tuberculosis coinfection, and those with poor virologic control are required.

    Matched MeSH terms: Viral Load/drug effects*
  12. Ku SW, Jiamsakul A, Joshi K, Pasayan MKU, Widhani A, Chaiwarith R, et al.
    J Int AIDS Soc, 2019 03;22(3):e25264.
    PMID: 30924281 DOI: 10.1002/jia2.25264
    INTRODUCTION: Cotrimoxazole (CTX) is recommended as prophylaxis against Pneumocystis jiroveci pneumonia, malaria and other serious bacterial infections in HIV-infected patients. Despite its in vitro activity against Mycobacterium tuberculosis, the effects of CTX preventive therapy on tuberculosis (TB) remain unclear.

    METHODS: Adults living with HIV enrolled in a regional observational cohort in Asia who had initiated combination antiretroviral therapy (cART) were included in the analysis. Factors associated with new TB diagnoses after cohort entry and survival after cART initiation were analysed using Cox regression, stratified by site.

    RESULTS: A total of 7355 patients from 12 countries enrolled into the cohort between 2003 and 2016 were included in the study. There were 368 reported cases of TB after cohort entry with an incidence rate of 0.99 per 100 person-years (/100 pys). Multivariate analyses adjusted for viral load (VL), CD4 count, body mass index (BMI) and cART duration showed that CTX reduced the hazard for new TB infection by 28% (HR 0.72, 95% CI l 0.56, 0.93). Mortality after cART initiation was 0.85/100 pys, with a median follow-up time of 4.63 years. Predictors of survival included age, female sex, hepatitis C co-infection, TB diagnosis, HIV VL, CD4 count and BMI.

    CONCLUSIONS: CTX was associated with a reduction in the hazard for new TB infection but did not impact survival in our Asian cohort. The potential preventive effect of CTX against TB during periods of severe immunosuppression should be further explored.

    Matched MeSH terms: Viral Load
  13. Abdul Ahmad SA, Palanisamy UD, Khoo JJ, Dhanoa A, Syed Hassan S
    Virol. J., 2019 02 27;16(1):26.
    PMID: 30813954 DOI: 10.1186/s12985-019-1127-7
    BACKGROUND: Dengue continues to be a major international public health concern. Despite that, there is no clinically approved antiviral for treatment of dengue virus (DENV) infections. In this study, geraniin extracted from the rind of Nephelium lappaceum was shown to inhibit the replication of DENV-2 in both in vitro and in vivo experiments.

    METHODS: The effect of geraniin on DENV-2 RNA synthesis in infected Vero cells was tested using quantitative RT-PCR. The in vivo efficacy of geraniin in inhibiting DENV-2 infection was then tested using BALB/c mice with geraniin administered at three different times. The differences in spleen to body weight ratio, DENV-2 RNA load and liver damage between the three treatment groups as compared to DENV-2 infected mice without geraniin administration were determined on day eight post-infection.

    RESULTS: Quantitative RT-PCR confirmed the decrease in viral RNA synthesis of infected Vero cells when treated with geraniin. Geraniin seemed to provide a protective effect on infected BALB/c mice liver when given at 24 h pre- and 24 h post-infection as liver damage was observed to be very mild even though a significant reduction of DENV-2 RNA load in serum was not observed in these two treatment groups. However, when administered at 72 h post-infection, severe liver damage in the form of necrosis and haemorrhage had prevailed despite a substantial reduction of DENV-2 RNA load in serum.

    CONCLUSIONS: Geraniin was found to be effective in reducing DENV-2 RNA load when administered at 72 h post-infection while earlier administration could prevent severe liver damage caused by DENV-2 infection. These results provide evidence that geraniin is a potential candidate for the development of anti-dengue drug.

    Matched MeSH terms: Viral Load
  14. Rich KM, Valencia Huamaní J, Kiani SN, Cabello R, Elish P, Florez Arce J, et al.
    AIDS Care, 2018 11;30(11):1341-1350.
    PMID: 29843518 DOI: 10.1080/09540121.2018.1476657
    In Peru, HIV is concentrated among men who have sex with men (MSM) and transgender women (TGW). Between June 2015 and August 2016, 591 HIV-positive MSM and TGW were recruited at five clinical care sites in Lima, Peru. We found that 82.4% of the participants had achieved viral suppression (VS; VL viral suppression (MVS; VL 
    Matched MeSH terms: Viral Load*
  15. Yun SI, Song BH, Frank JC, Julander JG, Olsen AL, Polejaeva IA, et al.
    Viruses, 2018 08 11;10(8).
    PMID: 30103523 DOI: 10.3390/v10080422
    Zika virus (ZIKV) causes no-to-mild symptoms or severe neurological disorders. To investigate the importance of viral and host genetic variations in determining ZIKV infection outcomes, we created three full-length infectious cDNA clones as bacterial artificial chromosomes for each of three spatiotemporally distinct and genetically divergent ZIKVs: MR-766 (Uganda, 1947), P6-740 (Malaysia, 1966), and PRVABC-59 (Puerto Rico, 2015). Using the three molecularly cloned ZIKVs, together with 13 ZIKV region-specific polyclonal antibodies covering nearly the entire viral protein-coding region, we made three conceptual advances: (i) We created a comprehensive genome-wide portrait of ZIKV gene products and their related species, with several previously undescribed gene products identified in the case of all three molecularly cloned ZIKVs. (ii) We found that ZIKV has a broad cell tropism in vitro, being capable of establishing productive infection in 16 of 17 animal cell lines from 12 different species, although its growth kinetics varied depending on both the specific virus strain and host cell line. More importantly, we identified one ZIKV-non-susceptible bovine cell line that has a block in viral entry but fully supports the subsequent post-entry steps. (iii) We showed that in mice, the three molecularly cloned ZIKVs differ in their neuropathogenicity, depending on the particular combination of viral and host genetic backgrounds, as well as in the presence or absence of type I/II interferon signaling. Overall, our findings demonstrate the impact of viral and host genetic variations on the replication kinetics and neuropathogenicity of ZIKV and provide multiple avenues for developing and testing medical countermeasures against ZIKV.
    Matched MeSH terms: Viral Load
  16. Ng KT, Oong XY, Lim SH, Chook JB, Takebe Y, Chan YF, et al.
    Clin. Infect. Dis., 2018 07 02;67(2):261-268.
    PMID: 29385423 DOI: 10.1093/cid/ciy063
    Background: Rhinovirus (RV) is one of the main viral etiologic agents of acute respiratory illnesses. Despite the heightened disease burden caused by RV, the viral factors that increase the severity of RV infection, the transmission pattern, and seasonality of RV infections remain unclear.

    Methods: An observational study was conducted among 3935 patients presenting with acute upper respiratory illnesses in the ambulatory settings between 2012 and 2014.

    Results: The VP4/VP2 gene was genotyped from all 976 RV-positive specimens, where the predominance of RV-A (49%) was observed, followed by RV-C (38%) and RV-B (13%). A significant regression in median nasopharyngeal viral load (VL) (P < .001) was observed, from 883 viral copies/µL at 1-2 days after symptom onset to 312 viral copies/µL at 3-4 days and 158 viral copies/µL at 5-7 days, before declining to 35 viral copies/µL at ≥8 days. In comparison with RV-A (median VL, 217 copies/µL) and RV-B (median VL, 275 copies/µL), RV-C-infected subjects produced higher VL (505 copies/µL; P < .001). Importantly, higher RV VL (median, 348 copies/µL) was associated with more severe respiratory symptoms (Total Symptom Severity Score ≥17, P = .017). A total of 83 phylogenetic-based transmission clusters were identified in the population. It was observed that the relative humidity was the strongest environmental predictor of RV seasonality in the tropical climate.

    Conclusions: Our findings underline the role of VL in increasing disease severity attributed to RV-C infection, and unravel the factors that fuel the population transmission dynamics of RV.

    Matched MeSH terms: Viral Load*
  17. Barré-Sinoussi F, Abdool Karim SS, Albert J, Bekker LG, Beyrer C, Cahn P, et al.
    J Int AIDS Soc, 2018 07;21(7):e25161.
    PMID: 30044059 DOI: 10.1002/jia2.25161
    INTRODUCTION: Globally, prosecutions for non-disclosure, exposure or transmission of HIV frequently relate to sexual activity, biting, or spitting. This includes instances in which no harm was intended, HIV transmission did not occur, and HIV transmission was extremely unlikely or not possible. This suggests prosecutions are not always guided by the best available scientific and medical evidence.

    DISCUSSION: Twenty scientists from regions across the world developed this Expert Consensus Statement to address the use of HIV science by the criminal justice system. A detailed analysis of the best available scientific and medical research data on HIV transmission, treatment effectiveness and forensic phylogenetic evidence was performed and described so it may be better understood in criminal law contexts. Description of the possibility of HIV transmission was limited to acts most often at issue in criminal cases. The possibility of HIV transmission during a single, specific act was positioned along a continuum of risk, noting that the possibility of HIV transmission varies according to a range of intersecting factors including viral load, condom use, and other risk reduction practices. Current evidence suggests the possibility of HIV transmission during a single episode of sex, biting or spitting ranges from no possibility to low possibility. Further research considered the positive health impact of modern antiretroviral therapies that have improved the life expectancy of most people living with HIV to a point similar to their HIV-negative counterparts, transforming HIV infection into a chronic, manageable health condition. Lastly, consideration of the use of scientific evidence in court found that phylogenetic analysis alone cannot prove beyond reasonable doubt that one person infected another although it can be used to exonerate a defendant.

    CONCLUSIONS: The application of up-to-date scientific evidence in criminal cases has the potential to limit unjust prosecutions and convictions. The authors recommend that caution be exercised when considering prosecution, and encourage governments and those working in legal and judicial systems to pay close attention to the significant advances in HIV science that have occurred over the last three decades to ensure current scientific knowledge informs application of the law in cases related to HIV.

    Matched MeSH terms: Viral Load
  18. Oong XY, Chook JB, Ng KT, Chow WZ, Chan KG, Hanafi NS, et al.
    Virol. J., 2018 05 23;15(1):91.
    PMID: 29792212 DOI: 10.1186/s12985-018-1005-8
    BACKGROUND: Human metapneumovirus (HMPV) is established as one of the causative agents of respiratory tract infections. To date, there are limited reports that describe the effect of HMPV genotypes and/or viral load on disease pathogenesis in adults. This study aims to determine the role of HMPV genetic diversity and nasopharyngeal viral load on symptom severity in outpatient adults with acute respiratory tract infections.
    METHODS: Severity of common cold symptoms of patients from a teaching hospital was assessed by a four-category scale and summed to obtain the total symptom severity score (TSSS). Association between the fusion and glycoprotein genes diversity, viral load (quantified using an improved RT-qPCR assay), and symptom severity were analyzed using bivariate and linear regression analyses.
    RESULTS: Among 81/3706 HMPV-positive patients, there were no significant differences in terms of demographics, number of days elapsed between symptom onset and clinic visit, respiratory symptoms manifestation and severity between different HMPV genotypes/sub-lineages. Surprisingly, elderly patients (≥65 years old) had lower severity of symptoms (indicated by TSSS) than young and middle age adults (p = 0.008). Nasopharyngeal viral load did not correlate with nor predict symptom severity of HMPV infection. Interestingly, at 3-5 days after symptom onset, genotype A-infected patients had higher viral load compared to genotype B (4.4 vs. 3.3 log10 RNA copies/μl) (p = 0.003).
    CONCLUSIONS: Overall, HMPV genetic diversity and viral load did not impact symptom severity in adults with acute respiratory tract infections. Differences in viral load dynamics over time between genotypes may have important implications on viral transmission.
    Study site: Primary Care Clinic, University of Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia
    Matched MeSH terms: Viral Load
  19. Loeliger KB, Altice FL, Desai MM, Ciarleglio MM, Gallagher C, Meyer JP
    Lancet HIV, 2018 02;5(2):e96-e106.
    PMID: 29191440 DOI: 10.1016/S2352-3018(17)30209-6
    BACKGROUND: Incarceration provides an opportunity for engagement in HIV care but is associated with poor HIV treatment outcomes after release. We aimed to assess post-release linkage to HIV care (LTC) and the effect of transitional case management services.

    METHODS: To create a retrospective cohort of all adults with HIV released from jails and prisons in Connecticut, USA (2007-14), we linked administrative custody and pharmacy databases with mandatory HIV/AIDS surveillance monitoring and case management data. We examined time to LTC (defined as first viral load measurement after release) and viral suppression at LTC. We used generalised estimating equations to show predictors of LTC within 14 days and 30 days of release.

    FINDINGS: Among 3302 incarceration periods for 1350 individuals between 2007 and 2014, 672 (21%) of 3181 periods had LTC within 14 days of release, 1042 (34%) of 3064 had LTC within 30 days of release, and 301 (29%) of 1042 had detectable viral loads at LTC. Factors positively associated with LTC within 14 days of release are intermediate (31-364 days) incarceration duration (adjusted odds ratio 1·52; 95% CI 1·19-1·95), and transitional case management (1·65; 1·36-1·99), receipt of antiretroviral therapy during incarceration (1·39; 1·11-1·74), and two or more medical comorbidities (1·86; 1·48-2·36). Reincarceration (0·70; 0·56-0·88) and conditional release (0·62; 0·50-0·78) were negatively associated with LTC within 14 days. Hispanic ethnicity, bonded release, and psychiatric comorbidity were also associated with LTC within 30 days but reincarceration was not.

    INTERPRETATION: LTC after release is suboptimal but improves when inmates' medical, psychiatric, and case management needs are identified and addressed before release. People who are rapidly cycling through jail facilities are particularly vulnerable to missed linkage opportunities. The use of integrated programmes to align justice and health-care goals has great potential to improve long-term HIV treatment outcomes.

    FUNDING: US National Institutes of Health.

    Matched MeSH terms: Viral Load
  20. Farhanah MI, Yasmin AR, Mat Isa N, Hair-Bejo M, Ideris A, Powers C, et al.
    J. Gen. Virol., 2018 Jan;99(1):21-35.
    PMID: 29058656 DOI: 10.1099/jgv.0.000956
    Infectious bursal disease is a highly contagious disease in the poultry industry and causes immunosuppression in chickens. Genome-wide regulations of immune response genes of inbred chickens with different genetic backgrounds, following very virulent infectious bursal disease virus (vvIBDV) infection are poorly characterized. Therefore, this study aims to analyse the bursal tissue transcriptome of six inbred chicken lines 6, 7, 15, N, O and P following infection with vvIBDV strain UK661 using strand-specific next-generation sequencing, by highlighting important genes and pathways involved in the infected chicken during peak infection at 3 days post-infection. All infected chickens succumbed to the infection without major variations among the different lines. However, based on the viral loads and bursal lesion scoring, lines P and 6 can be considered as the most susceptible lines, while lines 15 and N were regarded as the least affected lines. Transcriptome profiling of the bursa identified 4588 genes to be differentially expressed, with 2985 upregulated and 1642 downregulated genes, in which these genes were commonly or uniquely detected in all or several infected lines. Genes that were upregulated are primarily pro-inflammatory cytokines, chemokines and IFN-related. Various genes that are associated with B-cell functions and genes related to apoptosis were downregulated, together with the genes involved in p53 signalling. In conclusion, bursal transcriptome profiles of different inbred lines showed differential expressions of pro-inflammatory cytokines and chemokines, Th1 cytokines, JAK-STAT signalling genes, MAPK signalling genes, and their related pathways following vvIBDV infection.
    Matched MeSH terms: Viral Load
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