坦桑尼亚达累斯萨拉姆非疫情暴发期间登革热病毒传播情况：一项横断面调查。

Dengue virus transmission during non-outbreak period in Dar Es Salaam, Tanzania: a cross-sectional survey.

机构信息

School of Life Sciences and Bioengineering, Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania.

Department of Public Health, Institute of Tropical Medicine, Antwerpen, Belgium.

出版信息

BMC Infect Dis. 2024 Oct 29;24(1):1219. doi: 10.1186/s12879-024-10109-5.

DOI:10.1186/s12879-024-10109-5

PMID:39472806

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC11520832/

Abstract

BACKGROUND

Tanzania has experienced multiple dengue outbreaks between 2010 and 2019, caused by various dengue virus (DENV) strains. In 2019, there were 6917 confirmed dengue cases and 13 deaths in Tanzania. Routine diagnosis of dengue fever is unfortunately excluded, particularly during non-outbreak periods, resulting in delayed outbreak detection and control. The aim of this study was to improve early detection and control measures for DENV by investigating its circulation in human and Aedes aegypti (A.aegypti) mosquitoes during the non-outbreak periods in Dar es Salaam, Tanzania, which is an area frequently affected by dengue outbreaks.

METHODS

Four hundred and fifteen (415) blood samples were collected from patients attending randomly selected health facilities in five wards; Azimio, Keko, Mtoni, Mbagala and Chamazi within Temeke district. The samples were tested for DENV NS1 antigen and anti-dengue IgM and IgG antibodies by rapid test. Then, 150 out of 415 blood samples were tested for the DENV by conventional Reverse Transcriptase Polymerase Chain Reaction (RT-PCR). Two thousand two hundred and fifty (2,250) adult female A.aegypti mosquitoes were collected using a Prokopack aspirator and BG sentinel trap or obtained after rearing immature stages and tested, in pools of 15 for DENV by RT-PCR. Statistical Software, SPSS version 23, was used for data analysis.

RESULTS

Of the tested blood samples, 17% (71/415) were positive by NS1 antigen, 0.5% (2/415) by IgM, 0.5% (2/415) by IgG antibodies, and 0.5% (2/415) by IgM and IgG. None of the samples tested positive by DENV RT-PCR. Moreover, 3.3% (5/150) of tested mosquito pools had DENV by RT-PCR. Individuals aged between 21 and 40 years of age had increased risk of testing positive for DENV NS1 antigen, followed by those aged 5-20 years old, particularly those residing from Azimio ward, Keko ward, Mtoni ward and Mbagala ward, p-value ≤ 0.05.

CONCLUSION

Findings from this study revealed evidence of DENV circulation during non-outbreak periods in Dar es Salaam, Tanzania. These findings underscore the importance of including testing for dengue infection in routine differential diagnoses of febrile cases, and also frequent dengue surveillance in mosquitos. This proactive approach will help early DENV outbreak detection and control in the country.

摘要

背景

坦桑尼亚在 2010 年至 2019 年期间经历了多次登革热疫情，由各种登革热病毒（DENV）株引起。2019 年，坦桑尼亚有 6917 例确诊登革热病例和 13 例死亡。不幸的是，登革热的常规诊断被排除在外，特别是在非疫情期间，这导致了疫情的延迟发现和控制。本研究旨在通过调查坦桑尼亚达累斯萨拉姆在非疫情期间登革热病毒在人和埃及伊蚊（Aedes aegypti）中的传播情况，改善对 DENV 的早期检测和控制措施，因为该地区经常受到登革热疫情的影响。

方法

从五个区（阿齐米奥、凯科、姆托尼、姆巴加拉和查马齐）的五个随机选择的卫生机构就诊的患者中采集了 415 份（415 份）血液样本。使用快速检测法检测 DENV NS1 抗原和抗登革热 IgM 和 IgG 抗体。然后，对 415 份血液样本中的 150 份进行常规逆转录聚合酶链反应（RT-PCR）检测 DENV。使用 Prokopack 吸气器和 BG 哨兵陷阱收集了 2250 只成年雌性埃及伊蚊，或在饲养幼体后获得，并对其进行了检测，将 15 只蚊子的样本混合在一起进行 DENV 的 RT-PCR 检测。使用统计软件 SPSS 版本 23 进行数据分析。

结果

在检测的血液样本中，17%（71/415）的 NS1 抗原阳性，0.5%（2/415）的 IgM 阳性，0.5%（2/415）的 IgG 阳性，0.5%（2/415）的 IgM 和 IgG 阳性。没有样本通过 DENV RT-PCR 检测呈阳性。此外，3.3%（5/150）的蚊子检测池通过 RT-PCR 检测到 DENV。年龄在 21 至 40 岁之间的个体检测出 DENV NS1 抗原的风险增加，其次是 5 至 20 岁的个体，特别是来自阿齐米奥区、凯科区、姆托尼区和姆巴加拉区的个体，p 值≤0.05。