Effectiveness of CoronaVac in the prevention of COVID-19, a test-negative case-control study in Brazil.

The present study aimed to evaluate the effectiveness of two doses of CoronaVac in preventing SARS-CoV-2 symptomatic disease with virological confirmation, as well as in the prevention of COVID-19 moderate and severe cases. A test-negative unmatched case-control design was used, in which cases were patients with suspected COVID-19 (presenting at least two of the following symptoms: fever, chills, sore throat, headache, cough, runny nose, olfactory or taste disorders) with virological confirmation, and controls were those whose SARS-CoV-2 test was negative. As for exposure, participants were classified as unvaccinated, or vaccinated with a complete schedule. Suspected COVID-19 cases were identified from March to November 2021, in two cities located in the State of São Paulo, Brazil. All participants signed the Informed Consent Form before enrollment. RT-PCR results and vaccination data were obtained from the local surveillance systems. Up to two phone calls were made to obtain information on the outcome of the cases. A total of 2981 potential participants were screened for eligibility, of which 2163 were included, being 493 cases and 1670 controls. Vaccination, age, the reported contact with a COVID-19 suspected or confirmed case in the 14 days before symptoms onset, and the educational level were the variables independently associated with the outcome. The adjusted vaccine effectiveness for symptomatic COVID-19 (AVE) was 39.0 % (95 % CI 6.0-60.0 %). The AVE in the prevention of moderate and severe disease was 91.0 % (95 % CI 76.0-97.0 %). Our results were influenced by the waning of the Gamma variant, in the second trimester of 2021, followed by the increase in vaccination coverage, and a drop in the number of cases in the second half of the year. The study demonstrated the high effectiveness of CoronaVac in preventing moderate/severe COVID-19 cases.

The emergence of novel SARS-CoV-2 variant P.1 in Amazonas (Brazil) was temporally associated with a change in the age and sex profile of COVID-19 mortality: A population based ecological study.

BACKGROUND: Since the end of 2020, there has been a great deal of international concern about the variants of SARS-COV-2 B.1.1.7, identified in the United Kingdom; B.1.351 discovered in South Africa and P.1, originating from the Brazilian state of Amazonas. The three variants were associated with an increase in transmissibility and worsening of the epidemiological situation in the places where they expanded. The lineage B.1.1.7 was associated with the increase in case fatality rate in the United Kingdom. There are still no studies on the case fatality rate of the other two variants. The aim of this study was to analyze the mortality profile before and after the emergence of the P.1 strain in the Amazonas state. METHODS: We analyzed data from the Influenza Epidemiological Surveillance Information System, SIVEP-Gripe (Sistema de Informação de Vigilância Epidemiológica da Gripe), comparing two distinct epidemiological periods: during the peak of the first wave, between April and May 2020, and in January 2021 (the second wave), the month in which the new variant came to predominate. We calculated mortality rates, overall case fatality rate and case fatality rate among hospitalized patients; all rates were calculated by age and gender and 95% confidence intervals (95% CI) were determined. FINDINGS: We observed that in the second wave there were a higher incidence and an increase in the proportion of cases of COVID-19 in the younger age groups. There was also an increase in the proportion of women among Severe Acute Respiratory Infection (SARI) cases from 40% (2,709) in the first wave to 47% (2,898) in the second wave and in the proportion of deaths due to COVID-19 between the two periods varying from 34% (1,051) to 47% (1,724), respectively. In addition, the proportion of deaths among people between 20 and 59 years old has increased in both sexes. The case fatality rate among those hospitalized in the population between 20 and 39 years old during the second wave was 2.7 times the rate observed in the first wave (female rate ratio = 2.71; 95% CI: 1.9-3.9], p <0.0001; male rate ratio = 2.70, 95%CI:2.0-3.7), and in the general population the rate ratios were 1.15 (95% CI: 1.1-1.2) in females and 0.78 (95% CI: 0.7-0.8) in males]. INTERPRETATION: Based on this prompt analysis of the epidemiological scenario in the Amazonas state, the observed changes in the pattern of mortality due to COVID-19 between age groups and gender simultaneously with the emergence of the P.1 strain suggest changes in the pathogenicity and virulence profile of this new variant. Further studies are needed to better understanding of SARS-CoV-2 variants profile and their impact for the health population. FUNDING: There was no funding for this study.

The emergence of novel SARS-CoV-2 variant P.1 in Amazonas (Brazil) was temporally associated with a change in the age and gender profile of COVID-19 mortality / A emergência da nova variante P.1 do SARS-CoV-2 no Amazonas (Brasil) foi temporalmente associada a uma mudança no perfil da mortalidade devido a COVID-19, segundo sexo e idade

Background Since the end of 2020, there has been a great deal of international concern about the variants of SARS-COV-2 B.1.1.7, identified in the United Kingdom; B.1.351 discovered in South Africa and P.1, originating from the Brazilian state of Amazonas. The three variants were associated with an increase in transmissibility and worsening of the epidemiological situation in the places where they expanded. The lineage B.1.1.7 was associated with the increase in case fatality rate in the United Kingdom. There are still no studies on the case fatality rate of the other two variants. The aim of this study was to analyze the mortality profile before and after the emergence of the P.1 strain in the Amazonas state. Methods We analyzed data from the Influenza Epidemiological Surveillance Information System, SIVEP-Gripe (Sistema de Informação de Vigilância Epidemiológica da Gripe), comparing two distinct epidemiological periods: during the peak of the first wave, between April and May 2020, and in January 2021 (the second wave), the month in which the new variant came to predominate. We calculated mortality rates, overall case fatality rate and case fatality rate among hospitalized patients; all rates were calculated by age and gender and 95% confidence intervals (95% CI) were determined. Findings We observed that in the second wave there were a higher incidence and an increase in the proportion of cases of COVID-19 in the younger age groups. There was also an increase in the proportion of women among Severe Acute Respiratory Infection (SARI) cases from 40% (2,709) in the first wave to 47% (2,898) in the second wave and in the proportion of deaths due to COVID-19 between the two periods varying from 34% (1,051) to 47% (1,724), respectively. In addition, the proportion of deaths among people between 20 and 59 years old has increased in both sexes. The case fatality rate among those hospitalized in the population between 20 and 39 years old during the second wave was 2.7 times the rate observed in the first wave (female rate ratio = 2.71; 95% CI: 1.9-3.9], p <0.0001; male rate ratio = 2.70, 95%CI:2.0-3.7), and in the general population the rate ratios were 1.15 (95% CI: 1.1-1.2) in females and 0.78 (95% CI: 0.7-0.8) in males]. Interpretation Based on this prompt analysis of the epidemiological scenario in the Amazonas state, the observed changes in the pattern of mortality due to COVID-19 between age groups and gender simultaneously with the emergence of the P.1 strain suggest changes in the pathogenicity and virulence profile of this new variant. Further studies are needed to better understanding of SARS-CoV-2 variants profile and their impact for the health population.

Introdução Desde o final de 2020 tem havido grande preocupação internacional com as variantes do SARS-COV-2: B.1.1.7, identificada no Reino Unido; B.1.351, descoberta na África do Sul e P.1, que emergiu inicialmente estado brasileiro do Amazonas. As três variantes foram associadas a aumento na transmissibilidade e piora da situação epidemiológica nos locais onde se expandiram. A linhagem B.1.1.7 foi associada ao aumento da taxa de letalidade no Reino Unido. Ainda não existem estudos conclusivos sobre letalidade das outras duas variantes. O objetivo deste estudo foi analisar o perfil de mortalidade antes e depois da emergência da linhagem P.1 no Amazonas. Métodos Analisamos os dados do sistema nacional de vigilância epidemiológica, comparando dois momentos epidemiológicos distintos: durante o pico da primeira onda, entre abril e maio de 2020, e em janeiro de 2021, mês em que a nova variante passou a predominar. Calculamos as taxas de mortalidade, letalidade e letalidade entre pacientes internados, todas as taxas foram calculadas por idade e por sexo e determinados os intervalos de confiança de 95%. Achados Observamos que na segunda onda houve maior incidência e aumento na proporção de casos de COVID-19 nas faixas etárias mais jovens. Observou-se, também, um aumento na proporção de mulheres entre os casos de SARI de 40% (2.709) na primeira onda para 47% (2.898) na segunda onda e entre mortes por COVID-19 de 34% (1,051) para 47% (1.724), respectivamente. Além disso, a proporção de mortes entre 20 e 59 anos aumentou em ambos os sexos. A letalidade entre os hospitalizados na população entre 20 e 39 anos durante a segunda onda foi 2.7 vezes a primeira onda [razão de taxas sexo feminino=2,71; CI(95%)=1,9-3,9], p<0.0001; razão de taxas sexo masculino=2.70(2.0-3.7)), na população geral as razões de taxa foram 1,15(1,1-1,2) no sexo feminino e 0,78(0,7-0,8) no sexo masculino. Interpretação Observamos mudanças no padrão de mortalidade por COVID-19 entre as faixas etárias e sexo simultaneamente à emergência da linhagem P.1, sugerindo mudanças nos perfis de patogenicidade e virulência, novos estudos são necessários para melhor compreensão das variantes do SARS-CoV-2 e suas consequências na saúde da população.

Etiologies of rash and fever illnesses in Campinas, Brazil.

BACKGROUND: Few population-based studies of infectious etiologies of fever-rash illnesses have been conducted. This study reports on enhanced febrile-rash illness surveillance in Campinas, Brazil, a setting of low measles and rubella virus transmission. METHODS: Cases of febrile-rash illnesses in individuals aged <40 years that occurred during the period 1 May 2003-30 May 2004 were reported. Blood samples were collected for laboratory diagnostic confirmation, which included testing for adenovirus, dengue virus, Epstein-Barr virus (EBV), enterovirus, human herpes virus 6 (HHV6), measles virus, parvovirus-B19, Rickettsia rickettsii, rubella virus, and group A streptococci (GAS) infections. Notification rates were compared with the prestudy period. RESULTS: A total of 1248 cases were notified, of which 519 (42%) had laboratory diagnosis. Of these, HHV-6 (312 cases), EBV (66 cases), parvovirus (30 cases), rubella virus (30 cases), and GAS (30 cases) were the most frequent causes of infection. Only 10 rubella cases met the rubella clinical case definition currently in use. Notification rates were higher during the study than in the prestudy period (181 vs 52.3 cases per 100,000 population aged <40 years). CONCLUSIONS: Stimulating a passive surveillance system enhanced its sensitivity and resulted in additional rubella cases detected. In settings with rubella elimination goals, rubella testing may be considered for all cases of febrile-rash illness, regardless of suspected clinical diagnosis.

Risk factors for death from pandemic (H1N1) 2009, southern Brazil.

To identify risk factors for death from pandemic (H1N1) 2009, we obtained data for 157 hospitalized patients with confirmed cases of this disease. Multivariate analysis showed that diabetes and class III obesity were associated with death. These findings helped define priority vaccination groups in Brazil.

Setor privado de saúde e a vigilância da síndrome febril exantemática: uma experiência municipal / Private Health Sector and Rash and Fever Illnesses Surveillance: a Municipal Experience

Entre 2003 e 2004, o Município de Campinas, Estado de São Paulo, Brasil, desenvolveu um sistema de vigilância de doenças febris exantemáticas (VigiFEx) para o conhecimento da epidemiologia dessas doenças, na ausência de casos autóctones de sarampo e baixa incidência da rubéola. O objetivo deste estudo foi descrever as estratégias utilizadas para a incorporação do setor privado ao VigiFEx e sua participação na vigilância dessas doenças. Analisou-se o número de unidades notificadoras e a proporção de casos notificados pelos setores público e privado de saúde, antes e durante o VigiFEx. Observou-se aumento do percentual de unidades notificadoras do setor privado (de 14,5 para 28,0% p<0,05) bem como do percentual de casos notificados por esse mesmo setor (de 1,6 para 8,3% p<0,05). A proporção de notificações do setor privado foi maior no início do VigiFEx. Conclui-se que é possível a adesão da rede privada ao sistema de vigilância epidemiológica mediante estratégias específicas. Sugerem-se atividades para fortalecer a articulação entre as redes pública e privada de saúde.

From 2003 to 2004, a rash and fever syndromic surveillance system (VigiFEx) was implemented in the Municipality of Campinas, State of São Paulo, Brazil, to understand disease epidemiology in a setting with low incidence of rubella and no transmission of measles. The purpose of that system was to know the epidemiology of those diseases when there were no auctoctone cases of measles and low incidence of rubella. The objective of this study was to describe strategies for incorporation of the private health sector into surveillance activities, and its participation in that surveillance system. The proportion of notifying units and notified cases by the private and public health sectors before and during VigiFEx were analyzed. An increase in the proportion of private sector notifying units was observed (from 14.5 to 28.0%: p-value <0.05); as well as an increase in the proportion of cases notified through the private sector (from 1.6 to 8.3%: p-value <0.05). Notification by the private sector was higher in the beginning of VigiFEx. In conclusion, increased participation of the private healthcare sector in surveillance activities is feasible as far as specific strategies are used. The authors suggest specific activities to integrate public and private healthcare sectors.