Influenza A(H1N1)pdm09 infection and viral load analysis in patients with different clinical presentations
Influenza A(H1N1)pdm09 infection and viral load analysis in patients with different clinical presentations
复制标题
DOI：
10.1590/0074-02760200009
复制
发表时间：
2020-01-01
期刊：
影响因子：
--
通讯作者：
Bellei, Nancy
中科院分区：
文献类型：
--
作者：
Rodrigues Guimarães Alves, Vitória;Perosa, Ana Helena;Bellei, Nancy
背景流感病毒载量(VL)是决定病毒清除的抗病毒效果的决定性因素。目的本研究旨在评估在巴西某三级医院就诊的不同人群中流感病毒载量(VL)的感染率及其对临床疾病谱的影响。总共分析了2262个样本，并将其分为三组：(I)无症状(AS)；(Ii)有症状的门诊患者(OP)；以及(Iii)住院患者(HP)。针对M基因，以人RNAseP为内对照，以归一化基因为阈值，通过实时定量一步逆转录聚合酶链式反应(RT-PCR)计算VL(以log10个RNA拷贝数/毫升为单位)。年龄0.08~77岁[中位数+/-标准差(SD)：12.5+/-20.54]。5-11岁儿童的检出率最高(p<；0.0001)。AS患者的VL最低，与有症状患者相比差异有统计学意义(P=0.0003)。在发病两天内观察到较高的VL。10例患者(HP组)接受了抗病毒治疗，并进行了随访，平均初始VL为6.64+/-1.82。这些患者中50%的患者在治疗12天后病毒完全清除。主要结论评估AS患者作为潜在的传播者是重要的，因为即使在较低的VL仍然存在病毒脱落。我们的结果表明，有潜在疾病和严重临床症状的患者可能会考虑延长病毒治疗时间。
BACKGROUND Influenza viral load (VL) can be a decisive factor in determining the antiviral efficacy in viral clearance.OBJECTIVE This study aimed to evaluate the rate of infection and the role of influenza VL on the clinical spectrum of illnesses among different patient groups attended at a tertiary hospital in Brazil.METHODS Samples were collected from patients presenting acute respiratory infection from 2009 to 2013. Overall, 2262 samples were analysed and distributed into three groups: (i) asymptomatic (AS); (ii) symptomatic outpatients (OP); and (iii) hospitalised patients ( HP). VL (expressed in Log10 RNA copies/mL) was calculated through a quantitative real-time one-step reverse transcription-polymerase chain reaction (RT-PCR) assay aimed at the M gene, with human RNAseP target as internal control and normalising gene of threshold cycle values.FINDINGS A total of 162 (7.16%) H1N1pdm09 positive samples were analysed. Patients aged from 0.08 to 77 years old [median +/- standard deviation (SD): 12.5 +/- 20.54]. Children with 5 to 11 years old presented the highest detection (p < 0.0001). AS patients had the lowest VL, with a significant difference when compared with symptomatic patients (p = 0.0003). A higher VL was observed within two days of disease onset. Ten patients (HP group) received antiviral treatment and were followed up and presented a mean initial VL of 6.64 +/- 1.82. A complete viral clearance for 50% of these patients was reached after 12 days of treatment.MAIN CONCLUSIONS It is important to evaluate AS patients as potential spreaders, as viral shedding was still present, even at lower VL. Our results suggest that patients with underlying diseases and severe clinical symptoms may be considered for prolonged viral treatment.