Interacting Epidemics in Amazonian Brazil: Prior Dengue Infection Associated with Increased COVID-19 Risk in a Population-Based Cohort Study
Nicolete VC., Rodrigues PT., Johansen IC., Corder RM., Tonini J., Cardoso MA., de Jesus JG., Claro IM., Faria NR., Sabino EC., Castro MC., Ferreira MU.
Abstract Background Immunity after dengue virus (DENV) infection has been suggested to cross-protect from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and mortality. Methods We tested whether serologically proven prior DENV infection diagnosed in September-October 2019, before the coronavirus 2019 (COVID-19) pandemic, reduced the risk of SARS-CoV-2 infection and clinically apparent COVID-19 over the next 13 months in a population-based cohort in Amazonian Brazil. Mixed-effects multiple logistic regression analysis was used to identify predictors of infection and disease, adjusting for potential individual and household-level confounders. Virus genomes from 14 local SARS-CoV-2 isolates were obtained using whole-genome sequencing. Results Anti-DENV IgG was found in 37.0% of 1,285 cohort participants (95% confidence interval [CI], 34.3% to 39.7%) in 2019, with 10.4 (95% CI, 6.7 to 15.5) seroconversion events per 100 person-years during the follow-up. In 2020, 35.2% of the participants (95% CI, 32.6% to 37.8%) had anti-SARS-CoV-2 IgG and 57.1% of the 448 SARS-CoV-2 seropositives (95% CI, 52.4% to 61.8%) reported clinical manifestations at the time of infection. Participants aged >60 y were twice more likely to have symptomatic COVID-19 than under-five children. Locally circulating SARS-CoV-2 isolates were assigned to the B.1.1.33 lineage. Contrary to the cross-protection hypothesis, prior DENV infection was associated with twice the risk of clinically apparent COVID-19 upon SARS-CoV-2 infection, with P values between 0.025 and 0.039 after adjustment for identified confounders. Conclusion Higher risk of clinically apparent COVID-19 among individuals with prior dengue has important public health implications for communities sequentially exposed to DENV and SARS-CoV-2 epidemics.