RESUMEN
Zika virus (ZIKV) caused a public health threat in the United States in 2016, leading to rapid development and implementation of blood screening assays for ZIKV RNA. Several ZIKV sequences from clinical cases have been reported, but none from asymptomatic/pre-symptomatic infections. We isolated and sequenced ZIKV from asymptomatic/pre-symptomatic blood donor (ABD-ZIKV) samples and compared with reported clinical sequences. Twelve ABD-ZIKV isolates were produced from 67 cultivated samples, and isolates were genetically similar among themselves. Most isolates shared mutations with the clinical isolate PRVABC59 2015, whereas two ABD-ZIKV isolates shared specific mutations with U.S. clinical isolates from 2016. The ABD-ZIKV strains clustered into two distinct subclades: one comprised mostly ABD-ZIKV from Puerto Rico, and another one comprised ABD-ZIKV from Florida and QTX-02 isolate (Puerto Rico). In this study, we showed the circulation of two slightly distinct virus strains among Puerto Rico blood donors, one of which was also reported in Florida.
Asunto(s)
Donantes de Sangre , Filogenia , Infección por el Virus Zika/sangre , Virus Zika/genética , Virus Zika/aislamiento & purificación , Adulto , Enfermedades Transmisibles Emergentes/sangre , Enfermedades Transmisibles Emergentes/epidemiología , Florida/epidemiología , Genómica , Humanos , Puerto Rico/epidemiología , Infección por el Virus Zika/diagnóstico , Infección por el Virus Zika/epidemiologíaRESUMEN
BACKGROUND: Zika virus (ZIKV), a mosquito-borne flavivirus, causes asymptomatic infections in blood donors and can be transmitted by transfusion. During the 2016 US outbreak, universal individual-donation nucleic acid testing (ID-NAT) was used to screen the blood supply for ZIKV. Testing pooled samples from multiple donations with minipool (MP)-NAT is less sensitive than ID-NAT, which raised questions about its utility in ZIKV outbreaks. STUDY DESIGN AND METHODS: A mathematical model and computer simulation determined the risk of missing ID-NAT-reactive and immunoglobulin (Ig) M-negative donations in a ZIKV outbreak if MP-NAT is used initially instead of ID-NAT. The model calculated the time required for ZIKV RNA to replicate to a concentration detectable by testing donations individually or in pools of 6 (MP6) or 16 (MP16). A computer simulation then randomly selected infection times to determine the probability of detection by the candidate tests. RESULTS: The probability of detecting the first ID-NAT-reactive unit in an outbreak is 92% (2.5th-97.5th percentile, 79%-99%) by MP6 and 85% (2.5th-97.5th percentile, 67%-99%) by MP16. When one donation is detected by MP-NAT, the model predicts that the chance of having missed one or more ID-NAT-reactive donations is 8% to 15%. The probability of missing a unit by MP-NAT is constant over the course of the outbreak (8% by MP6, 15% by MP16). CONCLUSION: The model predicts that the probability that a candidate MP-NAT will detect the first ID-NAT-reactive unit in a ZIKV outbreak is 85% to 92% and remains constant over time.
Asunto(s)
Donantes de Sangre , ARN Viral/sangre , Infección por el Virus Zika/sangre , Virus Zika/genética , Transfusión Sanguínea , Simulación por Computador , Humanos , Inmunoglobulina M/sangre , Modelos Teóricos , Puerto Rico/epidemiología , Estados Unidos/epidemiología , Infección por el Virus Zika/epidemiología , Infección por el Virus Zika/prevención & controlRESUMEN
In this investigation, machine-enhanced techniques were applied to bring about scientific insights to identify a minimum set of phenotypic/functional memory-related biomarkers for post-vaccination follow-up upon yellow fever (YF) vaccination. For this purpose, memory status of circulating T-cells (Naïve/early-effector/Central-Memory/Effector-Memory) and B-cells (Naïve/non-Classical-Memory/Classical-Memory) along with the cytokine profile (IFN/TNF/IL-5/IL-10) were monitored before-NV(day0) and at distinct time-points after 17DD-YF primary vaccination-PV(day30-45); PV(year1-9) and PV(year10-11). A set of biomarkers (eEfCD4; EMCD4; CMCD19; EMCD8; IFNCD4; IL-5CD8; TNFCD4; IFNCD8; TNFCD8; IL-5CD19; IL-5CD4) were observed in PV(day30-45), but not in NV(day0), with most of them still observed in PV(year1-9). Deficiencies of phenotypic/functional biomarkers were observed in NV(day0), while total lack of memory-related attributes was observed in PV(year10-11), regardless of the age at primary vaccination. Venn-diagram analysis pre-selected 10 attributes (eEfCD4, EMCD4, CMCD19, EMCD8, IFNCD4, IL-5CD8, TNFCD4, IFNCD8, TNFCD8 and IL-5CD4), of which the overall mean presented moderate accuracy to discriminate PV(day30-45)&PV(year1-9) from NV(day0)&PV(year10-11). Multi-parameter approaches and decision-tree algorithms defined the EMCD8 and IL-5CD4 attributes as the top-two predictors with moderated performance. Together with the PRNT titers, the top-two biomarkers led to a resultant memory status observed in 80% and 51% of volunteers in PV(day30-45) and PV(year1-9), contrasting with 0% and 29% found in NV(day0) and PV(year10-11), respectively. The deficiency of memory-related attributes observed at PV(year10-11) underscores the conspicuous time-dependent decrease of resultant memory following17DD-YF primary vaccination that could be useful to monitor potential correlates of protection in areas under risk of YF transmission.
Asunto(s)
Anticuerpos Antivirales/sangre , Biomarcadores/sangre , Vacunación , Vacuna contra la Fiebre Amarilla/inmunología , Fiebre Amarilla/prevención & control , Virus de la Fiebre Amarilla/inmunología , Adolescente , Adulto , Anciano , Linfocitos B/inmunología , Linfocitos T CD8-positivos/inmunología , Citocinas/sangre , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo , Fiebre Amarilla/inmunología , Fiebre Amarilla/virología , Adulto JovenRESUMEN
In this study, strategies for serum biomarker assessment were developed for therapeutic monitoring of HCV patients. For this purpose, serum chemokine/cytokine levels were measured by cytometric-bead-array in HCV patients, categorized according to immunotherapy response as: non-responder/NR, relapser/REL and sustained-virologic-responder/SVR. The results demonstrated an overall increase of serum chemokine/cytokine levels in HCV patients. In general, therapeutic failure was associated with presence of a predominant baseline proinflammatory pattern with enhanced CCL5/RANTES, IFN-α, IFN-γ along with decreased IL-10 levels in NR and increased IL-6 and TNF in REL. SVR displayed lower baseline proinflammatory status with decreased CXCL8/IL-8, IL-12 and IL-17 levels. The inability to uphold IFN-α levels during immunotherapy was characteristic of NR. Serum chemokine/cytokine signatures further support the deleterious effect of proinflammatory baseline status and the critical role of increased/persistent IFN-α levels to guarantee the sustained virologic response. The prominent baseline proinflammatory milieu observed in NR and REL yielded a restricted biomarker network with small number of neighborhood connections, whereas SVR displayed a network with integrated cytokine connectivity. Noteworthy was that SVR presented a shift towards a proinflammatory pattern upon immunotherapy, assuming a pattern similar to that observed in NR and REL at baseline. Moreover, the immunotherapy guided REL towards a profile similar to SVR at baseline. Analysis of baseline-fold changes during treatment pointed out IFN-α and TNF as high-performance biomarkers to monitor immunotherapy outcome. This knowledge may contribute for novel insights into the treatment and control of the continuous public health threat posed by HCV infection worldwide.
Asunto(s)
Antivirales/uso terapéutico , Quimiocinas/sangre , Citocinas/sangre , Monitoreo de Drogas/métodos , Hepatitis C Crónica/terapia , Adulto , Anciano , Biomarcadores Farmacológicos/sangre , Femenino , Hepatitis C Crónica/sangre , Humanos , Inmunoterapia , Interferón alfa-2 , Interferón-alfa/uso terapéutico , Interleucina-12/sangre , Interleucina-17/sangre , Interleucina-8/sangre , Masculino , Persona de Mediana Edad , Polietilenglicoles/uso terapéutico , Proteínas Recombinantes/uso terapéutico , Carga Viral/efectos de los fármacos , Adulto JovenRESUMEN
BACKGROUND: Dengue is a mosquito-borne viral disease caused by the four dengue viruses (DENV-1 to 4) that can also be transmitted by blood transfusion and organ transplantation. The distribution of DENV in the components of blood from infected donors is poorly understood. METHODS: We used an in-house TaqMan qRT-PCR assay to test residual samples of plasma, cellular components of whole blood (CCWB), serum and clot specimens from the same collection from blood donors who were DENV-RNA-reactive in a parallel blood safety study. To assess whether DENV RNA detected by TaqMan was associated with infectious virus, DENV infectivity in available samples was determined by culture in mosquito cells. RESULTS: DENV RNA was detected by TaqMan in all tested blood components, albeit more consistently in the cellular components; 78.8% of CCWB, 73.3% of clots, 86.7% of sera and 41.8% of plasma samples. DENV-1 was detected in 48 plasma and 97 CCWB samples while DENV-4 was detected in 21 plasma and 31 CCWB samples. In mosquito cell cultures, 29/111 (26.1%) plasma and 32/97 (32.7%) CCWB samples were infectious. A subset of samples from 29 donors was separately analyzed to compare DENV viral loads in the available blood components. DENV viral loads did not differ significantly between components and ranged from 3-8 log10 PCR-detectable units/ml. CONCLUSIONS: DENV was present in all tested components from most donors, and viral RNA was not preferentially distributed in any of the tested components. Infectious DENV was also present in similar proportions in cultured plasma, clot and CCWB samples, indicating that these components may serve as a resource when sample sizes are limited. However, these results suggest that the sensitivity of the nucleic acid tests (NAT) for these viruses would not be improved by testing whole blood or components other than plasma.