Regional Virus Research and Diagnostic Laboratory, ICMR-National Institute of Cholera & Enteric Diseases, Kolkata, West Bengal, India.
Department of Microbiology, Shri Ramkrishna Institute of Medical Sciences & Sanaka Hospitals, Durgapur, West Bengal, India.
Indian J Med Res. 2022 Oct-Nov;156(4&5):608-614. doi: 10.4103/ijmr.IJMR_2612_19.
BACKGROUND & OBJECTIVES: Regional Virus Research and Diagnostic Laboratory established at ICMR-National Institute of Cholera and Enteric Diseases (NICED) regularly receives samples for dengue screening and serotyping from patients of acute febrile illness (AFI) from Kolkata and adjacent districts. In this study, data over a three year period (August 2016-July 2019) was retrospectively analyzed to provide insight into the epidemiological trends of dengue fever in this region.
Serological screening of dengue was performed by detection of NS1 antigen and/or immunoglobulin M (IgM) antibody. Dengue serotyping was done by conventional or real-time reverse transcriptase-PCR. The data were analyzed to describe the distribution of dengue with respect to age of patient, duration of fever on the day of blood collection and month of the year. Zip codes were used for spatial plotting.
Out of the 24,474 samples received from Kolkata and its adjacent districts (Hooghly, Howrah, North and South 24 Parganas), 38.3 per cent (95% confidence interval: 37.7-38.9%) samples were screened positive for dengue. The correlation between age and dengue positivity was found to be weak. A combination of dengue NS1 antigen and dengue IgM antibody detection may be a better option for detecting dengue positivity compared to a single test. Most AFI cases were tested from August to November during the study period, with maximum dengue positivity noted during September (45.9%). The predominant serotype of 2016, dengue virus serotype 1 (DENV-1), was almost entirely replaced by DENV-2 in 2017 and 2018.
INTERPRETATION & CONCLUSIONS: Dengue continues to be an important cause of AFI in the region and round-the-year preventive measures are required for its control. Serotype switching is alarming and should be monitored routinely.
印度医学研究理事会-国家传染病研究所（ICMR-NICED）的区域病毒研究和诊断实验室定期接收来自加尔各答及其周边地区急性发热性疾病（AFI）患者的登革热筛查和血清分型样本。在这项研究中，对三年（2016 年 8 月至 2019 年 7 月）的数据进行了回顾性分析，以了解该地区登革热的流行病学趋势。
通过检测 NS1 抗原和/或免疫球蛋白 M（IgM）抗体进行登革热血清学筛查。通过常规或实时逆转录聚合酶链反应进行登革热血清分型。分析数据以描述登革热在患者年龄、采血当天发热持续时间和当年月份方面的分布。邮政编码用于空间绘图。
从加尔各答及其周边地区（豪拉、胡格利、北 24 帕加纳斯和南 24 帕加纳斯）收到的 24474 份样本中，38.3%（95%置信区间：37.7-38.9%）的样本检测出登革热阳性。年龄与登革热阳性之间的相关性较弱。与单一检测相比，登革热 NS1 抗原和登革热 IgM 抗体联合检测可能是检测登革热阳性的更好选择。在研究期间，大多数 AFI 病例在 8 月至 11 月进行检测，9 月（45.9%）登革热阳性率最高。2016 年的主要血清型为登革热病毒血清型 1（DENV-1），2017 年和 2018 年几乎完全被 DENV-2 取代。
登革热仍然是该地区 AFI 的一个重要原因，需要全年采取预防措施加以控制。血清型转换令人担忧，应定期监测。
