Background
We investigated frequency of reinfection with seasonal coronaviruses (HCoV) and serum antibody response following infection over 8 years in the Household Influenza Vaccine Evaluation cohort.
Methods
Households were followed annually for identification of acute respiratory illness with RT-PCR confirmed HCoV infection. Serum collected before and at two time points post infection were tested using a multiplex binding assay to quantify antibody to seasonal, SARS-CoV-1, and SARS-CoV-2 spike proteins and SARS-CoV-2 spike sub-domains and N protein.
Results
Of 3418 participants, 40% were followed for ≥3years. A total of 1004 HCoV infections were documented; 303 (30%) were reinfections of any HCoV type. The number of HCoV infections ranged from 1 to 13 per individual. The mean time to reinfection with the same type was estimated at 983 days for 229E, 578 days for HKU1, 615 days for OC43, and 711 days for NL63. Binding antibody levels to seasonal HCoVs were high, with little increase post-infection, and were maintained over time. Homologous, pre-infection antibody levels did not significantly correlate with odds of infection, and there was little cross response to SARS-CoV-2 proteins.
Conclusions
Reinfection with seasonal HCoVs is frequent. Binding anti-spike protein antibodies do not correlate with protection from seasonal HCoV infection.
Background
We established the first prospective cohort to understand how infection with dengue virus is influenced by vector-specific determinants like humoral immunity to Aedes aegypti salivary proteins.
Methods
Children aged two to nine years old enrolled in the PAGODAS (Pediatric Assessment Group of Dengue and Aedes Saliva) cohort with informed consent by their guardians. Children were followed semi-annually for antibodies to dengue and to proteins in Ae. aegypti salivary gland homogenate using enzyme-linked immunosorbent assays and dengue-specific neutralization titers. Children presented with fever at any time for dengue testing.
Results
From July 13 to August 30, 2018, we enrolled 771 children. At baseline, 22% (173/770) had evidence of neutralizing antibodies to one or more dengue serotypes. By April 2020, 51 children had symptomatic dengue while 148 dengue-naïve children had inapparent dengue defined by neutralization assays. In a multivariate model, individuals with higher antibodies to Ae. aegypti salivary proteins were 1.5x more likely to have dengue infection (HR 1.47 95% CI 1.05–2.06; p=0.02), particularly individuals with inapparent dengue (HR 1.64 95% CI 1.12–2.41; p=0.01).
Conclusions
High levels of seropositivity to Ae. aegypti salivary proteins are associated with future development of dengue infection, primarily inapparent, in dengue-naïve Cambodian children.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.