Background & objectives: India has been reporting the cases of coronavirus disease 2019 (COVID-19) since January 30, 2020. The Indian Council of Medical Research (ICMR) formulated and established laboratory surveillance for COVID-19. In this study, an analysis of the surveillance data was done to describe the testing performance and descriptive epidemiology of COVID-19 cases by time, place and person.
Methods: The data were extracted from January 22 to April 30, 2020. The frequencies of testing performance were described over time and by place. We described cases by time (epidemic curve by date of specimen collection; seven-day moving average), place (area map) and person (attack rate by age, sex and contact status), and trends were represented along with public health measures and events.
Results: Between January 22 and April 30, 2020, a total of 1,021,518 individuals were tested for severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). Testing increased from about 250 individuals per day in the beginning of March to 50,000 specimens per day by the end of April 2020. Overall, 40,184 (3.9%) tests were reported positive. The proportion of positive cases was highest among symptomatic and asymptomatic contacts, 2-3-fold higher than among those with severe acute respiratory infection, or those with an international travel history or healthcare workers. The attack rate (per million) by age was highest among those aged 50-69 yr (63.3) and was lowest among those under 10 yr (6.1). The attack rate was higher among males (41.6) than females (24.3). The secondary attack rate was 6.0 per cent. Overall, 99.0 per cent of 736 districts reported testing and 71.1 per cent reported COVID-19 cases.
Interpretation & conclusions: The coverage and frequency of ICMR's laboratory surveillance for SARS-CoV-2 improved over time. COVID-19 was reported from most parts of India, and the attack rate was more among men and the elderly and common among close contacts. Analysis of the data indicates that for further insight, additional surveillance tools and strategies at the national and sub-national levels are needed.


中文翻译：

---

印度 SARS-CoV-2 的实验室监测：2020 年 1 月 22 日至 4 月 30 日检测到的 COVID-19 的测试和描述性流行病学表现。


背景和目标：自 2020 年 1 月 30 日以来，印度一直在报告 2019 年冠状病毒病 (COVID-19) 病例。印度医学研究委员会 (ICMR) 制定并建立了对 COVID-19 的实验室监测。在这项研究中，对监测数据进行了分析，以按时间、地点和人员描述 COVID-19 病例的检测性能和描述性流行病学。
方法：数据提取时间为 2020 年 1 月 22 日至 4 月 30 日。测试性能的频率随时间和地点的变化进行了描述。我们按时间（按样本采集日期的流行曲线；7 天移动平均值）、地点（区域图）和人（按年龄、性别和接触状态的发病率）描述了病例，并且趋势与公共卫生措施和事件。
结果：在 2020 年 1 月 22 日至 4 月 30 日期间，共有 1,021,518 人接受了严重急性呼吸综合征冠状病毒 2 (SARS-CoV-2) 的检测。到 2020 年 4 月底，检测从 3 月初的每天约 250 人增加到每天 50,000 个样本。总体而言，有 40,184 人（3.9%）检测呈阳性。有症状和无症状接触者中阳性病例的比例最高，比严重急性呼吸道感染者、有国际旅行史者或医护人员高2-3倍。按年龄划分的发病率（每百万人）在 50-69 岁（63.3）中最高，在 10 岁以下（6.1）中最低。男性（41.6）的发病率高于女性（24.3）。二次攻击率为6.0%。总而言之，99。
解释和结论：随着时间的推移，ICMR 对 SARS-CoV-2 的实验室监测的覆盖范围和频率有所提高。印度大部分地区都报告了 COVID-19，男性和老年人的发病率更高，在密切接触者中也很常见。对数据的分析表明，为了进一步了解，需要在国家和次国家层面增加额外的监测工具和战略。