Indirect effectiveness of COVID-19 vaccines in the pre-omicron and omicron periods: A nation-wide test-negative case-control study in Brazil.

Objectives: Mass COVID-19 immunization campaigns altered the pandemic's progress by protecting the vaccine recipient and reducing transmission. However, evidence for indirect vaccine effectiveness (IVE) is limited due to the difficulties of ascertaining this type of protection.

Methods: Using linked national Brazilian databases, we adapted the test-negative design to evaluate the IVE against symptomatic infection.

Text mining method to unravel long COVID's clinical condition in hospitalized patients.

Long COVID is characterized by persistent that extends symptoms beyond established timeframes. Its varied presentation across different populations and healthcare systems poses significant challenges in understanding its clinical manifestations and implications. In this study, we present a novel application of text mining technique to automatically extract unstructured data from a long COVID survey conducted at a prominent university hospital in São Paulo, Brazil.

Efficacy and safety of Butantan-DV in participants aged 2-59 years through an extended follow-up: results from a double-blind, randomised, placebo-controlled, phase 3, multicentre trial in Brazil.

Background: A single-dose dengue vaccine that protects individuals across a wide age range and regardless of dengue serostatus is an unmet need. We assessed the safety and efficacy of the live, attenuated, tetravalent Butantan-dengue vaccine (Butantan-DV) in adults, adolescents, and children. We previously reported the primary and secondary efficacy and safety endpoints in the initial 2 years of follow-up.

Socioeconomic determinants of cognition among older adults in the Brazilian longitudinal study of aging (ELSI-Brazil): a life-course approach.

Background: The prevalence of cognitive impairment no dementia (CIND) and dementia appears to be higher in low- and middle-income countries (LMICs) compared to high-income economies. Yet few nationally representative studies from Latin American LMICs have investigated life-course socioeconomic factors associated with the susceptibility to these two cognitive conditions. Hence, the present study aimed to examine the associations of early- (education and food insecurity), mid- (employment stability), and late-life (personal income and household per capita income) socioeconomic determinants of CIND and dementia among older adults from Brazil, while simultaneously exploring whether sex plays an effect-modifier role on these associations.