Tang Nicole, Lim Jue Tao, Dickens Borame, Chiew Calvin, Ng Lee Ching, Chia Po Ying, Leo Yee Sin, Lye David Chien, Tan Kelvin Bryan, Wee Liang En
National Centre for Infectious Diseases, Singapore, Singapore.
Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
Open Forum Infect Dis. 2024 Jul 13;11(8):ofae397. doi: 10.1093/ofid/ofae397. eCollection 2024 Aug.
Elucidating whether prior dengue potentially confers cross-protection against COVID-19 is of public health importance in tropical countries at risk of overlapping dengue and COVID-19 epidemics. However, studies to date have yielded conflicting results. We aimed to assess effects of recent prior dengue infection on risk and severity of subsequent SARS-CoV-2 infection among adult Singaporeans.
A retrospective cohort study including all adult Singaporeans aged ≥18 years was conducted from 1 July 2021 through 31 October 2022, when a dengue outbreak driven by the DENV3 serotype preceded subsequent waves of SARS-CoV-2 Delta/Omicron transmission in Singapore. SARS-CoV-2 and dengue infection status were classified using national registries. Cox regression models adjusted for demographics, COVID-19 vaccination status, comorbidity, and socioeconomic-status were used to assess risks and severity (hospitalization, severe illness) of SARS-CoV-2 infection occurring after previous recorded dengue infection.
A total of 3 366 399 individuals were included, contributing 1 399 696 530 person-days of observation. A total of 13 434 dengue infections and 1 253 520 subsequent SARS-CoV-2 infections were recorded; with an average of 94.7 days (standard deviation = 83.8) between dengue infection and SARS-CoV-2 infection. Preceding dengue infection was associated with a modest increase in risk of subsequent SARS-CoV-2 infection (adjusted hazards ratio [aHR] = 1.13; 95% confidence interval [CI], 1.08-1.17), and significantly elevated risk of subsequent COVID-19 hospitalization (aHR = 3.25; 95% CI, 2.78-3.82) and severe COVID-19 (aHR = 3.39; 95% CI, 2.29-5.03.
Increased risk of SARS-CoV-2 infection and adverse COVID-19 outcomes were observed following preceding dengue infection in a national population-based cohort of adult Singaporeans. This observation is of significance in tropical countries with overlapping dengue and COVID-19 outbreaks.
在登革热和新冠疫情有重叠风险的热带国家，阐明既往感染登革热是否能对新冠病毒产生交叉保护具有重要的公共卫生意义。然而，迄今为止的研究结果相互矛盾。我们旨在评估近期既往感染登革热对成年新加坡人后续感染新冠病毒的风险及严重程度的影响。
开展一项回顾性队列研究，纳入所有年龄≥18岁的成年新加坡人，研究时间为2021年7月1日至2022年10月31日，在此期间，新加坡先出现了由登革热病毒3型引发的登革热疫情，随后出现了新冠病毒德尔塔/奥密克戎毒株的传播浪潮。利用国家登记系统对新冠病毒和登革热感染状况进行分类。采用经人口统计学、新冠疫苗接种状况、合并症和社会经济状况调整的Cox回归模型，评估既往记录的登革热感染后发生新冠病毒感染的风险和严重程度（住院、重症）。
共纳入3366399人，累计观察1399696530人日。共记录到13434例登革热感染和1253520例后续新冠病毒感染；登革热感染与新冠病毒感染之间的平均间隔时间为94.7天（标准差=83.8）。既往登革热感染与后续新冠病毒感染风险适度增加相关（调整后风险比[aHR]=1.13；95%置信区间[CI]，1.08-1.17），且后续新冠病毒住院风险显著升高（aHR=3.25；95%CI，2.78-3.82）以及重症新冠病毒感染风险显著升高（aHR=3.39；95%CI，2.29-5.03）。
在以全国成年新加坡人为基础的队列研究中，观察到既往感染登革热后新冠病毒感染风险及不良新冠疫情结局增加。这一观察结果在登革热和新冠疫情有重叠的热带国家具有重要意义。
