Infection-Induced Immunity Is Associated With Protection Against Severe Acute Respiratory Syndrome Coronavirus 2 Infection and Decreased Infectivity.

Background: The impact of infection-induced immunity on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission has not been well established. Here we estimate the effects of prior infection induced immunity in adults and children on SARS-CoV-2 transmission in households.

Methods: We conducted a household cohort study from March 2020-November 2022 in Managua, Nicaragua; following a housheold SARS-CoV-2 infection, household members are closely monitored for infection.

High Co-circulation of Influenza and Severe Acute Respiratory Syndrome Coronavirus 2.

In the first 2 years of the coronavirus disease 2019 pandemic, influenza transmission decreased substantially worldwide, meaning that health systems were not faced with simultaneous respiratory epidemics. In 2022, however, substantial influenza transmission returned to Nicaragua where it co-circulated with severe acute respiratory syndrome coronavirus 2, causing substantial disease burden.

SARS-CoV-2 infection-induced immunity and the duration of viral shedding: Results from a Nicaraguan household cohort study.

Background: Much of the world's population has been infected with SARS-CoV-2. Thus, immunity from prior infection will play a critical role in future SARS-CoV-2 transmission. We investigated the impact of infection-induced immunity on viral shedding duration and viral load.

High co-circulation of influenza and SARS-CoV-2.

In the first two years of the COVID-19 pandemic, influenza transmission decreased substantially worldwide meaning that health systems were not faced with simultaneous respiratory epidemics. In 2022, however, substantial influenza transmission returned to Nicaragua where it co-circulated with SARS-CoV-2 causing substantial disease burden.

Infection-induced immunity is associated with protection against SARS-CoV-2 infection, but not decreased infectivity during household transmission.

Background: Understanding the impact of infection-induced immunity on SARS-CoV-2 transmission will provide insight into the transition of SARS-CoV-2 to endemicity. Here we estimate the effects of prior infection induced immunity and children on SARS-CoV-2 transmission in households.

Methods: We conducted a household cohort study between March 2020-June 2022 in Managua, Nicaragua where when one household member tests positive for SARS-CoV-2, household members are closely monitored for SARS-CoV-2 infection.

Association of SARS-CoV-2 Seropositivity and Symptomatic Reinfection in Children in Nicaragua.

Importance: The impact of the SARS-CoV-2 pandemic on children remains unclear. Better understanding of the burden of COVID-19 among children and their risk of reinfection is crucial, as they will be among the last groups vaccinated.

Objective: To characterize the burden of COVID-19 and assess how risk of symptomatic reinfection may vary by age among children.

Burden of SARS-CoV-2 and protection from symptomatic second infection in children.

Importance: The impact of the SARS-CoV-2 pandemic on children remains unclear. Better understanding of the burden of COVID-19 among children and their protection against re-infection is crucial as they will be among the last groups vaccinated.

Objective: To characterize the burden of COVID-19 and assess how protection from symptomatic re-infection among children may vary by age.

An immune correlate of SARS-CoV-2 infection and severity of reinfections.

Background: An immune correlate of protection from SARS-CoV-2 infection is urgently needed.

Methods: We used an ongoing household cohort with an embedded transmission study that closely monitors participants regardless of symptom status. Real-time reverse-transcription polymerase chain reaction (RT-PCR) and Enzyme-linked immunosorbent assays (ELISAs) were used to measure infections and seropositivity.

Clinical Spectrum of Severe Acute Respiratory Syndrome Coronavirus 2 Infection and Protection From Symptomatic Reinfection.

Background: There are few data on the full spectrum of disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection across the lifespan from community-based or nonclinical settings.

Methods: We followed 2338 people in Managua, Nicaragua, aged <94 years from March 2020 through March 2021. SARS-CoV-2 infection was identified through real-time reverse transcription polymerase chain reaction (RT-PCR) or through enzyme-linked immunosorbent assay.

Epidemics of chikungunya, Zika, and COVID-19 reveal bias in case-based mapping.

Accurate tracing of epidemic spread over space enables effective control measures. We examined three metrics of infection and disease in a pediatric cohort (N≈3,000) over two chikungunya and one Zika epidemic, and in a household cohort (N=1,793) over one COVID-19 epidemic in Managua, Nicaragua. We compared spatial incidence rates (cases/total population), infection risks (infections/total population), and disease risks (cases/infected population).