Why shop on social media? A systematic review

Despite the vast possibilities of sales on social media, conversion rates for online sales on social media platforms are less than 1%. To understand how the purchase decision process occurs in social media, we conducted a systematic literature review to address Q1: what are the main factors impacting consumers buying behaviour the literature has brought to light? We also addressed Q2: how has the perception of marketing in social media evolved in recent years? Our results show six different reasons (trust, price, product's quality, influencer endorsement, word of mouth, and advertising) that motivate social media customers' purchase behaviour. Moreover, four of these reasons (trust, product's quality perception, influencer endorsement and word of mouth) are directly influenced by a factor inherent in the characteristics of social media, the social interaction. The COVID-19 pandemic has also led many consumers to buy through social media and we believe this is a permanent move.

The Covid-19 pandemic reinforces the need for sustainable health planning.

The 2030 Agenda for Sustainable Development highlighted the growing attention to the adequacy of health planning models to sustainable development. A re-reading of the results of a round table debate on "sustainable planning", which took place at the 5th National Congress of Tropical Medicine (Portugal, 2019) under a participant observation strategy, framed by the findings of a "synthesis of better evidence" literature review and cross-referenced with the reflections of different authors and experts about the momentum created by the COVID-19 pandemic, underlined the challenges to sustainable health planning that have emerged and are projected beyond the current pandemic context. Variable perceptions of the term "sustainable health development", leading to the potential loss of their relevance in guiding the elaboration of policies and strategic plans, and the potential higher effectiveness of the participatory approaches of health planning in achieving sustainable health were highlighted in the debate and literature, in general and in public health emergency contexts. Those results gained new relevance during the current COVID-19 pandemic, bringing back to the forefront a reflection of the inadequate planning framework that has usually been used to understand and respond to global health challenges, despite the already existing experience, evidence and support instruments.

Seroprevalence of SARS-CoV-2 Infection in Portugal in May-July 2020: Results of the First National Serological Survey (ISNCOVID-19).

INTRODUCTION: The aim of this study was to estimate and describe the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) specific antibodies (immunoglobulin M and/or immunoglobulin G) in Portugal in May-July 2020. MATERIAL AND METHODS: A cross-sectional seroepidemiological survey was developed after the peak of the first epidemic wave on a sample of 2301 Portuguese residents, aged 1 year or older. Survey sample was selected using a two-stage stratified non-probability sampling design (quota sampling). SARS-CoV-2 immunoglobulin M and immunoglobulin G antibodies were measured in serum samples by enzyme-linked immunosorbent assay. Seroprevalence estimates of immunoglobulin M and/or immunoglobulin G and 95% confidence intervals were stratified by sex, age group, health region and education. RESULTS: Overall, seroprevalence was 2.9% (95% confidence interval: 2.0% - 4.2%). Higher prevalence rates were observed in male (4.1%, 95% confidence interval: 2.6% - 6.6%) and those with secondary education (6.4%, 95% confidence interval: 3.2% - 12.5%). Differences in seroprevalence by age group and region were not statistically significant. DISCUSSION: The estimated seroprevalence of SARS-CoV-2 was higher than the cumulative incidence reported by the National Surveillance System but far from necessary to reach herd immunity. CONCLUSION: Our results support limited extent of infection by SARS-CoV-2 in the study population possibly due to early lockdown measures implemented in Portugal and support the need to continue monitoring of SARS-CoV-2 seroprevalence in order to increase our knowledge about the evolution of the epidemic and to estimate the proportion of the susceptible population over time.

Introdução: Este estudo tem como objetivo estimar e descrever a prevalência dos anticorpos específicos (imunoglobulina M e/ou imunoglobulina G) contra o vírus da síndrome respiratória aguda grave do coronavírus 2 (SARS-CoV-2) em Portugal em maio-julho de 2020. Material e Métodos: Após o pico da primeira onda epidémica foi realizado um estudo seroepidemiológico transversal numa amostra de 2301 pessoas residentes em Portugal, com idade igual ou superior a um ano. A amostra foi selecionada recorrendo um desenho amostral não probabilístico bietápico estratificado por quotas. Procedeu-se à deteção de anticorpos específicos contra SARS-CoV-2 (imunoglobulina M e imunoglobulina G) em amostras de soro por ensaio de imunoabsorção enzimática. As estimativas da seroprevalência (imunoglobulina M e/ou imunoglobulina G) e os respetivos intervalos de confiança a 95% foram estratificadas por sexo, grupo etário, região de saúde e escolaridade. Resultados: A seroprevalência de anticorpos específicos imunoglobulina M e/ou imunoglobulina G foi de 2,9 % (intervalo de confiança a 95%: 2,0% ­ 4,2%), tendo sido mais elevada em homens (4,1%, intervalo de confiança a 95%: 2,6% - 6,6%) e nos indivíduos com ensino secundário (6,4%, intervalo de confiança a 95%: 3,2% - 12,5%). Não foram identificadas diferenças estatisticamente significativas na entre os grupos etários estudados, nem entre regiões. Discussão: A seroprevalência estimada foi superior à incidência cumulativa de infeção reportada pelo Sistema Nacional de Vigilância, embora longe dos valores necessários para atingir a imunidade de grupo. Conclusão: Os resultados indicam uma extensão limitada da infeção por SARS-CoV-2, na população estudada compatível com uma implementação precoce das medidas de confinamento em Portugal e suporta a necessidade de monitorização a seroprevalência de SARS-CoV-2 para conhecer a evolução da epidemia e proporção da população suscetível ao longo do tempo.