ICMR National Institute of Epidemiology, Chennai, Tamil Nadu, India.
ICMR National Institute for Research in Environmental Health, Bhopal, Madhya Pradesh, India.
PLoS One. 2021 Dec 3;16(12):e0260979. doi: 10.1371/journal.pone.0260979. eCollection 2021.
The Indian Council of Medical Research set up a pan-national laboratory network to diagnose and monitor Coronavirus disease 2019 (COVID-19). Based on these data, we describe the epidemiology of the pandemic at national and sub-national levels and the performance of the laboratory network.
We included surveillance data for individuals tested and the number of tests from March 2020 to January 2021. We calculated the incidence of COVID-19 by age, gender and state and tests per 100,000 population, the proportion of symptomatic individuals among those tested, the proportion of repeat tests and test positivity. We computed median (Interquartile range-IQR) days needed for selected surveillance activities to describe timeliness.
The analysis included 176 million individuals and 188 million tests. The overall incidence of COVID-19 was 0.8%, and 12,584 persons per 100,000 population were tested. 6.1% of individuals tested returned a positive result. Ten of the 37 Indian States and Union Territories accounted for about 75.6% of the total cases. Daily testing scaled up from 40,000 initially to nearly one million in March 2021. The median duration between symptom onset and sample collection was two (IQR = 0,3) days, median duration between both sample collection and testing and between testing and data entry were less than or equal to one day. Missing or invalid entries ranged from 0.01% for age to 0.7% for test outcome.
The laboratory network set-up by ICMR was scaled up massively over a short period, which enabled testing a large section of the population. Although all states and territories were affected, most cases were concentrated in a few large states. Timeliness between the various surveillance activities was acceptable, indicating good responsiveness of the surveillance system.
印度医学研究理事会设立了一个全国性实验室网络，以诊断和监测 2019 年冠状病毒病（COVID-19）。基于这些数据，我们描述了国家和次国家层面的大流行流行病学以及实验室网络的性能。
我们纳入了 2020 年 3 月至 2021 年 1 月期间个体检测和检测数量的监测数据。我们按年龄、性别和邦计算了 COVID-19 的发病率，以及每 10 万人的检测数量、检测人群中症状患者的比例、重复检测的比例和检测阳性率。我们计算了描述及时性的选定监测活动所需的中位数（四分位距-IQR）天数。
分析包括 1.76 亿人，1.88 亿次检测。COVID-19 的总发病率为 0.8%，每 10 万人中有 12584 人接受检测。6.1%的检测呈阳性。37 个印度邦和联邦属地中有 10 个占总病例的 75.6%左右。每日检测量从最初的 4 万例增加到 2021 年 3 月的近 100 万例。从症状出现到样本采集的中位数时间为 2 天（IQR=0，3），从样本采集到检测以及从检测到数据录入的中位数时间均少于或等于 1 天。年龄的缺失或无效条目范围为 0.01%，检测结果的缺失或无效条目范围为 0.7%。
ICMR 建立的实验室网络在短时间内大规模扩展，使大部分人口能够接受检测。尽管所有邦和属地都受到影响，但大多数病例集中在少数几个大邦。各项监测活动之间的及时性是可以接受的，表明监测系统反应良好。
