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1.
Acta Med Port ; 2022 Oct 26.
Article in English | MEDLINE | ID: covidwho-2091283

ABSTRACT

INTRODUCTION: Following a COVID-19 mass vaccination campaign, it is important to evaluate the population level of SARS-CoV-2 antibodies. The aim of this study was to estimate the seroprevalence rate of SARS-CoV-2 specific antibodies acquired due to infection or vaccination in the Portuguese population. MATERIAL AND METHODS: The National Serological Survey (third wave - ISN3COVID-19) is a cross-sectional nationwide epidemiological study developed on a sample of 4545 Portuguese residents aged one year or older, between the 28th September 2021 and the 19th November 2021. The SARS-CoV-2 anti-nucleoprotein and anti-spike IgG antibody levels were determined in serum samples using Abbott Chemiluminescent Microparticle Immunoassays. Seroprevalence estimates were stratified by age group, sex, administrative region and self-reported chronic conditions. Medians and respective 95% confidence intervals were used to describe the distribution of SARS-CoV-2 specific antibodies in specific population subgroups. RESULTS: The total seroprevalence rate of SARS-CoV-2 was 86.4% (95% CI: 85.2% to 87.6%). A higher seroprevalence rate was estimated for women (88.3%), 50 to 59 years-old (96.5%) and in those with two or more self-reported chronic conditions (90.8%). A higher IgG (anti-Spike) concentration was observed in individuals vaccinated with the booster dose (median = 1 2601.3 AU/mL; 95% CI: 4127.5 to 19 089.1). CONCLUSION: There was a significant increase in SARS-CoV-2 seroprevalence following the mass vaccination campaign in Portugal. It is important to continue to monitor the distribution of specific SARS-COV-2 antibody at the population level to further inform public health policies.

2.
Euro Surveill ; 27(26)2022 06.
Article in English | MEDLINE | ID: covidwho-1923991

ABSTRACT

As the COVID-19 pandemic began in early 2020, primary care influenza sentinel surveillance networks within the Influenza - Monitoring Vaccine Effectiveness in Europe (I-MOVE) consortium rapidly adapted to COVID-19 surveillance. This study maps system adaptations and lessons learned about aligning influenza and COVID-19 surveillance following ECDC / WHO/Europe recommendations and preparing for other diseases possibly emerging in the future. Using a qualitative approach, we describe the adaptations of seven sentinel sites in five European Union countries and the United Kingdom during the first pandemic phase (March-September 2020). Adaptations to sentinel systems were substantial (2/7 sites), moderate (2/7) or minor (3/7 sites). Most adaptations encompassed patient referral and sample collection pathways, laboratory testing and data collection. Strengths included established networks of primary care providers, highly qualified testing laboratories and stakeholder commitments. One challenge was the decreasing number of samples due to altered patient pathways. Lessons learned included flexibility establishing new routines and new laboratory testing. To enable simultaneous sentinel surveillance of influenza and COVID-19, experiences of the sentinel sites and testing infrastructure should be considered. The contradicting aims of rapid case finding and contact tracing, which are needed for control during a pandemic and regular surveillance, should be carefully balanced.


Subject(s)
COVID-19 , Influenza Vaccines , Influenza, Human , COVID-19/epidemiology , Europe/epidemiology , Humans , Influenza, Human/epidemiology , Influenza, Human/prevention & control , Pandemics/prevention & control , Primary Health Care , Sentinel Surveillance
3.
Euro Surveill ; 27(21)2022 05.
Article in English | MEDLINE | ID: covidwho-1875327

ABSTRACT

IntroductionIn July and August 2021, the SARS-CoV-2 Delta variant dominated in Europe.AimUsing a multicentre test-negative study, we measured COVID-19 vaccine effectiveness (VE) against symptomatic infection.MethodsIndividuals with COVID-19 or acute respiratory symptoms at primary care/community level in 10 European countries were tested for SARS-CoV-2. We measured complete primary course overall VE by vaccine brand and by time since vaccination.ResultsOverall VE was 74% (95% CI: 69-79), 76% (95% CI: 71-80), 63% (95% CI: 48-75) and 63% (95% CI: 16-83) among those aged 30-44, 45-59, 60-74 and ≥ 75 years, respectively. VE among those aged 30-59 years was 78% (95% CI: 75-81), 66% (95% CI: 58-73), 91% (95% CI: 87-94) and 52% (95% CI: 40-61), for Comirnaty, Vaxzevria, Spikevax and COVID-19 Vaccine Janssen, respectively. VE among people 60 years and older was 67% (95% CI: 52-77), 65% (95% CI: 48-76) and 83% (95% CI: 64-92) for Comirnaty, Vaxzevria and Spikevax, respectively. Comirnaty VE among those aged 30-59 years was 87% (95% CI: 83-89) at 14-29 days and 65% (95% CI: 56-71%) at ≥ 90 days between vaccination and onset of symptoms.ConclusionsVE against symptomatic infection with the SARS-CoV-2 Delta variant varied among brands, ranging from 52% to 91%. While some waning of the vaccine effect may be present (sample size limited this analysis to only Comirnaty), protection was 65% at 90 days or more between vaccination and onset.


Subject(s)
COVID-19 , Influenza Vaccines , Influenza, Human , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines , Europe/epidemiology , Humans , Influenza, Human/prevention & control , Primary Health Care , SARS-CoV-2 , Vaccination
4.
Commun Med (Lond) ; 2: 10, 2022.
Article in English | MEDLINE | ID: covidwho-1860427

ABSTRACT

Background: Genomic surveillance of SARS-CoV-2 in Portugal was rapidly implemented by the National Institute of Health in the early stages of the COVID-19 epidemic, in collaboration with more than 50 laboratories distributed nationwide. Methods: By applying recent phylodynamic models that allow integration of individual-based travel history, we reconstructed and characterized the spatio-temporal dynamics of SARS-CoV-2 introductions and early dissemination in Portugal. Results: We detected at least 277 independent SARS-CoV-2 introductions, mostly from European countries (namely the United Kingdom, Spain, France, Italy, and Switzerland), which were consistent with the countries with the highest connectivity with Portugal. Although most introductions were estimated to have occurred during early March 2020, it is likely that SARS-CoV-2 was silently circulating in Portugal throughout February, before the first cases were confirmed. Conclusions: Here we conclude that the earlier implementation of measures could have minimized the number of introductions and subsequent virus expansion in Portugal. This study lays the foundation for genomic epidemiology of SARS-CoV-2 in Portugal, and highlights the need for systematic and geographically-representative genomic surveillance.

5.
Evol Med Public Health ; 10(1): 142-155, 2022.
Article in English | MEDLINE | ID: covidwho-1788491

ABSTRACT

Background and objectives: To understand how organisms evolve, it is fundamental to study how mutations emerge and establish. Here, we estimated the rate of mutation accumulation of SARS-CoV-2 in vitro and investigated the repeatability of its evolution when facing a new cell type but no immune or drug pressures. Methodology: We performed experimental evolution with two strains of SARS-CoV-2, one carrying the originally described spike protein (CoV-2-D) and another carrying the D614G mutation that has spread worldwide (CoV-2-G). After 15 passages in Vero cells and whole genome sequencing, we characterized the spectrum and rate of the emerging mutations and looked for evidences of selection across the genomes of both strains. Results: From the frequencies of the mutations accumulated, and excluding the genes with signals of selection, we estimate a spontaneous mutation rate of 1.3 × 10 -6 ± 0.2 × 10-6 per-base per-infection cycle (mean across both lineages of SARS-CoV-2 ± 2SEM). We further show that mutation accumulation is larger in the CoV-2-D lineage and heterogeneous along the genome, consistent with the action of positive selection on the spike protein, which accumulated five times more mutations than the corresponding genomic average. We also observe the emergence of mutators in the CoV-2-G background, likely linked to mutations in the RNA-dependent RNA polymerase and/or in the error-correcting exonuclease protein. Conclusions and implications: These results provide valuable information on how spontaneous mutations emerge in SARS-CoV-2 and on how selection can shape its genome toward adaptation to new environments. Lay Summary: Each time a virus replicates inside a cell, errors (mutations) occur. Here, via laboratory propagation in cells originally isolated from the kidney epithelium of African green monkeys, we estimated the rate at which the SARS-CoV-2 virus mutates-an important parameter for understanding how it can evolve within and across humans. We also confirm the potential of its Spike protein to adapt to a new environment and report the emergence of mutators-viral populations where mutations occur at a significantly faster rate.

6.
Vaccines (Basel) ; 10(2)2022 Jan 20.
Article in English | MEDLINE | ID: covidwho-1649930

ABSTRACT

Vaccination is considered the most important measure to control the COVID-19 pandemic. Extensive follow-up studies with distinct vaccines and populations are able to promote robust and reliable data to better understand the effectiveness of this pharmacologic strategy. In this sense, we present data regarding binding and neutralizing (achieved by surrogate ELISA assay) antibodies throughout time, from vaccinated and previously infected (PI) health care workers (HCW) in Portugal. We analyzed serum samples of 132 HCW, who were vaccinated and with previous SARS-CoV-2 infection. Samples were collected before vaccination (baseline, M1), at second dose vaccine uptake (M2), and 25-70 days (M3) and 150-210 days (M4) after the second dose for vaccinated individuals. The IgG (anti-RBD/S) antibody geometric mean titers found on vaccinated HCW at M2 (GM = 116.1 BAU/mL; CI: 92.3-146.1) were significantly higher than those found on PI HCW at recruitment (M1) (GM = 35.9 BAU/mL; CI:15.4-83.4), and the neutralizing antibodies (nAb) were similar between these groups, of 93.2 UI/mL (95% CI 73.2-118.5) vs. 84.1 UI/mL (95% CI 40.4-155.9), respectively. We detected around 10-fold higher IgG (anti-RBD/S) antibodies titers in M3 when compared with M2, with a slight but significant decrease in titers from 36 days after the second dose vaccine uptake. The increase of nAb titers was correlated with IgG (anti-RBD/S) antibodies titers; however, in contrast to IgG (anti-RBD/S) antibodies titers, we did not detect a decrease in the nAb titer 36 days after a second vaccine dose uptake. At M4, a decrease of 8-fold in binding IgG (anti-RBD/S) and nAb was observed. No significant differences in antibody titers were observed by sex, age or chronic diseases. Our results suggest that IgG (anti-RBD/S) antibodies titers and nAb titers could be correlated, but an ongoing follow up of the cohort is required to better understand this correlation, and the duration of the immune response.

7.
Euro Surveill ; 26(45)2021 Nov.
Article in English | MEDLINE | ID: covidwho-1630353

ABSTRACT

We report a rapid increase in enterovirus D68 (EV-D68) infections, with 139 cases reported from eight European countries between 31 July and 14 October 2021. This upsurge is in line with the seasonality of EV-D68 and was presumably stimulated by the widespread reopening after COVID-19 lockdown. Most cases were identified in September, but more are to be expected in the coming months. Reinforcement of clinical awareness, diagnostic capacities and surveillance of EV-D68 is urgently needed in Europe.


Subject(s)
COVID-19 , Enterovirus D, Human , Enterovirus Infections , Enterovirus , Myelitis , Respiratory Tract Infections , Communicable Disease Control , Disease Outbreaks , Enterovirus D, Human/genetics , Enterovirus Infections/diagnosis , Enterovirus Infections/epidemiology , Europe/epidemiology , Humans , Myelitis/epidemiology , SARS-CoV-2
8.
Infect Dis (Lond) ; 54(6): 418-424, 2022 06.
Article in English | MEDLINE | ID: covidwho-1621501

ABSTRACT

BACKGROUND: Integrated approaches to surveillance of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection are important for public health actions. The 2nd National Serological Survey (ISN2COVID-19) aimed to characterize the extent of SARS-CoV-2 infection and vaccine-induced response in the Portuguese population following the third epidemic wave and the launch of the vaccination campaign. METHODS: A cross-sectional study was performed using data on 8463 Portuguese 1-79 years of age, collected in February and March, 2021. SARS-CoV-2 IgM and IgG (anti-nucleoprotein and anti-spike) antibodies were determined in serum samples using Abbott Architect chemiluminescent microparticle assays. Post-infection and vaccine-induced seroprevalence with 95% confidence intervals (95%CI) were estimated in the overall sample and stratified by population characteristics. RESULTS: The estimated seroprevalence was 15.5% (95%CI:14.6-16.5%), of which 13.5% (95%CI: 12.6-14.4%) was attributable to natural infection and 2.0% (95%CI:1.7-2.4%) to vaccination. The lowest seroprevelence was observed in persons aged 70-79 years (8.9% 95%CI:6.8-11.6), while seroprevalence in children (14.3%; 95%CI:11.5-17.6%) and adolescents (12.9%; 95%CI:10.5-15.7%) was similar to that of persons aged between 20 and 69 years. Of seropositive individuals, 22.6% (95%CI:19.7-25.9%) did not report any symptoms in 6 months prior to interview. Of persons with completed vaccination (2-doses), 98.6% (95%CI: 93.0-99.7%) had specific IgG (anti-S) antibodies. CONCLUSIONS: After the third epidemic wave, the post-infection SARS-CoV-2 seroprevalence was 1.7 times higher than the cumulative incidence based on PCR-testing, but was higher (2.7 times) in children may be due to the high proportion of asymptomatic and mild infections.


Subject(s)
COVID-19 , SARS-CoV-2 , Adolescent , Adult , Aged , Antibodies, Viral , COVID-19/epidemiology , Child , Cross-Sectional Studies , Humans , Immunoglobulin G , Middle Aged , Portugal/epidemiology , Seroepidemiologic Studies , Young Adult
9.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-296699

ABSTRACT

Vaccination is considered the most important measure to control the COVID-19 pandemic. Extensive fol-low-up studies with distinct vaccines and populations are able to promote robust and reliable data to better understand the effectiveness of this pharmacologic strategy. In this sense, we present data regarding binding and neutralizing antibodies throughout time, from vaccinated and previously infected (PI) health care work-ers (HCW) in Portugal. We analyzed serum samples of 132 HCW, vaccinated and with previous SARS-CoV-2 infection. Samples were collected before vaccination (baseline, M1), at second dose vaccine uptake (M2), and 25-70 days (M3) and 150-210 days (M4) after the second dose for vaccinated individuals. The IgG (anti-RBD/S) antibody geometric mean titer found on vaccinated HCW at M2 (814.7 AU/ml;95% CI 649.8-1021.5) were sig-nificantly higher than those found on PI HCW at recruitment (M1) (252.6 AU/ml;95% CI 108.7 - 587.1), and the neutralizing antibodies (nAb) were similar between these groups, 93.2 UI/ml (95% CI 73.2- 118.5) vs. 84.1 UI/ml (95% CI 40.4-155.9), respectively. We detected about 10-fold higher IgG (anti-RBD/S) antibodies titers in M3 when compared with M2, with a slightly but significant decrease in titers from 36 days after the second dose vaccine uptake. The increase of nAb titers were correlated with IgG (anti-RBD/S) antibodies titers, how-ever, contrasting to IgG (anti-RBD/S) antibodies titers, we did not detect a decrease in nAb titer from 36 days after a second vaccine dose uptake. At M4, was observed a decrease of 8-fold in binding IgG (anti-RBD/S) and nAb. No significant differences in antibody titers were observed by sex, age or chronic diseases. Our results suggest that IgG (anti-RBD/S) antibodies titers and nAb titers could be correlated, but ongoing follow up of the cohort, is required to better understand this correlation, and the duration of the immune response.

10.
mSphere ; 6(4): e0024421, 2021 08 25.
Article in English | MEDLINE | ID: covidwho-1329039

ABSTRACT

Recent studies have shown that persistent SARS-CoV-2 infections in immunocompromised patients can trigger the accumulation of an unusual high number of mutations with potential relevance at both biological and epidemiological levels. Here, we report a case of an immunocompromised patient (non-Hodgkin lymphoma patient under immunosuppressive therapy) with a persistent SARS-CoV-2 infection (marked by intermittent positivity) over at least 6 months. Viral genome sequencing was performed at days 1, 164, and 171 to evaluate SARS-CoV-2 evolution. Among the 15 single-nucleotide polymorphisms (SNPs) (11 leading to amino acid alterations) and 3 deletions accumulated during this long-term infection, four amino acid changes (V3G, S50L, N87S, and A222V) and two deletions (18-30del and 141-144del) occurred in the virus Spike protein. Although no convalescent plasma therapy was administered, some of the detected mutations have been independently reported in other chronically infected individuals, which supports a scenario of convergent adaptive evolution. This study shows that it is of the utmost relevance to monitor the SARS-CoV-2 evolution in immunocompromised individuals, not only to identify novel potentially adaptive mutations, but also to mitigate the risk of introducing "hyper-evolved" variants in the community. IMPORTANCE Tracking the within-patient evolution of SARS-CoV-2 is key to understanding how this pandemic virus shapes its genome toward immune evasion and survival. In the present study, by monitoring a long-term COVID-19 immunocompromised patient, we observed the concurrent emergence of mutations potentially associated with immune evasion and/or enhanced transmission, mostly targeting the SARS-CoV-2 key host-interacting protein and antigen. These findings show that the frequent oscillation in the immune status in immunocompromised individuals can trigger an accelerated virus evolution, thus consolidating this study model as an accelerated pathway to better understand SARS-CoV-2 adaptive traits and anticipate the emergence of variants of concern.


Subject(s)
COVID-19/immunology , Immune Evasion/immunology , Immunocompromised Host/immunology , Lymphoma, Non-Hodgkin/immunology , SARS-CoV-2/immunology , Amino Acids/genetics , Amino Acids/immunology , Animals , COVID-19/virology , Cell Line , Chlorocebus aethiops , Female , Genome, Viral/genetics , Genome, Viral/immunology , Humans , Immune Evasion/genetics , Immunization, Passive/methods , Lymphoma, Non-Hodgkin/virology , Middle Aged , Mutation/genetics , Mutation/immunology , Pandemics/prevention & control , SARS-CoV-2/genetics , Vero Cells , Virus Replication/genetics , Virus Replication/immunology
11.
Euro Surveill ; 26(29)2021 07.
Article in English | MEDLINE | ID: covidwho-1323061

ABSTRACT

We measured COVID-19 vaccine effectiveness (VE) against symptomatic SARS-CoV-2 infection at primary care/outpatient level among adults ≥ 65 years old using a multicentre test-negative design in eight European countries. We included 592 SARS-CoV-2 cases and 4,372 test-negative controls in the main analysis. The VE was 62% (95% CI: 45-74) for one dose only and 89% (95% CI: 79-94) for complete vaccination. COVID-19 vaccines provide good protection against COVID-19 presentation at primary care/outpatient level, particularly among fully vaccinated individuals.


Subject(s)
COVID-19 , SARS-CoV-2 , Adult , Aged , COVID-19 Vaccines , Europe , Humans , Primary Health Care
12.
Viruses ; 13(4)2021 04 01.
Article in English | MEDLINE | ID: covidwho-1167760

ABSTRACT

Dissemination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in healthcare institutions affects both patients and health-care workers (HCW), as well as the institutional capacity to provide essential health services. Here, we investigated an outbreak of SARS-CoV-2 in a "non-COVID-19" hospital ward unveiled by massive testing, which challenged the reconstruction of transmission chains. The contacts network during the 15-day period before the screening was investigated, and positive SARS-CoV-2 RNA samples were subjected to virus genome sequencing. Of the 245 tested individuals, 48 (21 patients and 27 HCWs) tested positive for SARS-CoV-2. HCWs were mostly asymptomatic, but the mortality among patients reached 57.1% (12/21). Phylogenetic reconstruction revealed that all cases were part of the same transmission chain. By combining contact tracing and genomic data, including analysis of emerging minor variants, we unveiled a scenario of silent SARS-CoV-2 dissemination, mostly driven by the close contact within the HCWs group and between HCWs and patients. This investigation triggered enhanced prevention and control measures, leading to more timely detection and containment of novel outbreaks. This study shows the benefit of combining genomic and epidemiological data for disclosing complex nosocomial outbreaks, and provides valuable data to prevent transmission of COVID-19 in healthcare facilities.


Subject(s)
COVID-19/transmission , Cross Infection/transmission , Disease Outbreaks , Genome, Viral/genetics , SARS-CoV-2/genetics , Adult , Aged , Aged, 80 and over , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19/virology , Contact Tracing , Cross Infection/epidemiology , Cross Infection/prevention & control , Cross Infection/virology , Disease Outbreaks/prevention & control , Female , Genetic Variation , Health Personnel/statistics & numerical data , Hospitals , Humans , Male , Middle Aged , Phylogeny , Portugal/epidemiology , RNA, Viral/genetics , SARS-CoV-2/classification , SARS-CoV-2/isolation & purification , Young Adult
13.
Behav Sci (Basel) ; 11(3)2021 Mar 14.
Article in English | MEDLINE | ID: covidwho-1136457

ABSTRACT

The COVID-19 pandemic has altered the normal course of life, with measures to reduce the virus spread impacting motherhood expectations and, in particular, breastfeeding practices. This study aimed to review evidence regarding the impact of COVID-19 on breastfeeding plans and how these relate to women's psychological outcomes. Searches were conducted on PubMed and Web of Science for studies in English, Spanish, and Portuguese between January 2020 and January 2021. All study designs and pre-prints were considered. Twelve studies were included. Reports suggest that COVID-19 impacts differently on breastfeeding plans, which in turn leads to distinctive mental health outcomes. Positive breastfeeding experiences have been observed when mothers perceive that they have more time for motherhood, which may be associated with better mental health outcomes. Negative breastfeeding experiences have been observed when mothers are separated from their newborns, when mothers struggle with breastfeeding, or when mothers perceive decreased family and professional support, which seems to be associated with worse mental health outcomes. These preliminary results highlight the need for further research into the association between COVID-19, breastfeeding expectations, and maternal mental health. Filling this gap will foster the development of guidelines and interventions to better support mothers experiencing the obstacles of COVID-19 pandemic.

14.
Euro Surveill ; 26(10)2021 03.
Article in English | MEDLINE | ID: covidwho-1136424

ABSTRACT

We show that the SARS-CoV-2 B.1.1.7 lineage is highly disseminated in Portugal, with the odds of B.1.1.7 proportion increasing at an estimated 89% (95% confidence interval: 83-95%) per week until week 3 2021. RT-PCR spike gene target late detection (SGTL) can constitute a useful surrogate to track B.1.1.7 spread, besides the spike gene target failure (SGTF) proxy. SGTL/SGTF samples were associated with statistically significant higher viral loads, but not with substantial shift in age distribution compared to non-SGTF/SGTL cases.


Subject(s)
COVID-19/virology , SARS-CoV-2/genetics , COVID-19/transmission , Humans , Portugal/epidemiology , Spike Glycoprotein, Coronavirus/genetics
15.
Acta Med Port ; 34(2): 87-94, 2021 Feb 01.
Article in English | MEDLINE | ID: covidwho-1110853

ABSTRACT

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.


Subject(s)
Antibodies, Viral/blood , COVID-19/immunology , Immunoglobulin G/blood , Immunoglobulin M/blood , SARS-CoV-2/immunology , Adolescent , Adult , Age Distribution , Aged , COVID-19/epidemiology , Child , Child, Preschool , Confidence Intervals , Cross-Sectional Studies , Educational Status , Epidemics , Female , Humans , Infant , Infant, Newborn , Male , Middle Aged , Portugal/epidemiology , Prevalence , Seroepidemiologic Studies , Sex Distribution , Young Adult
16.
Pediatr Infect Dis J ; 39(12): e439-e443, 2020 12.
Article in English | MEDLINE | ID: covidwho-998533

ABSTRACT

Coronavirus disease, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is mainly transmitted through droplets, but other ways of transmission have been hypothesized. We report a case of vertical transmission of SARS-CoV-2 in a preterm born to an infected mother, confirmed by the presence of the virus in the neonatal blood, nasopharyngeal and oropharyngeal swabs collected in the first half an hour of life. The neonate presented with acute respiratory distress, similar to the findings in severely affected adults. This case highlights the importance of pregnancy, labor and neonatal period surveillance of affected mothers and their newborns.


Subject(s)
COVID-19/complications , COVID-19/diagnosis , Infectious Disease Transmission, Vertical , Pregnancy Complications, Infectious/diagnosis , Pregnancy Complications, Infectious/etiology , Severe Acute Respiratory Syndrome/diagnosis , Severe Acute Respiratory Syndrome/etiology , Adult , Biomarkers , COVID-19/epidemiology , COVID-19/transmission , Female , Humans , Infant, Newborn , Polymerase Chain Reaction , Pregnancy , Pregnancy Complications, Infectious/epidemiology , Radiography, Thoracic , Severe Acute Respiratory Syndrome/epidemiology , Severe Acute Respiratory Syndrome/transmission , Tomography, X-Ray Computed
17.
Emerg Microbes Infect ; 9(1): 2488-2496, 2020 Dec.
Article in English | MEDLINE | ID: covidwho-900319

ABSTRACT

Genomic surveillance of SARS-CoV-2 was rapidly implemented in Portugal by the National Institute of Health in collaboration with a nationwide consortium of >50 hospitals/laboratories. Here, we track the geotemporal spread of a SARS-CoV-2 variant with a mutation (D839Y) in a potential host-interacting region involving the Spike fusion peptide, which is a target motif of anti-viral drugs that plays a key role in SARS-CoV-2 infectivity. The Spike Y839 variant was most likely imported from Italy in mid-late February and massively disseminated in Portugal during the early epidemic, becoming prevalent in the Northern and Central regions of Portugal where it represented 22% and 59% of the sampled genomes, respectively, by 30 April. Based on our high sequencing sampling during the early epidemics [15.5% (1275/8251) and 6.0% (1500/24987) of all confirmed cases until the end of March and April, respectively], we estimate that, between 14 March and 9 April (covering the epidemic exponential phase) the relative frequency of the Spike Y839 variant increased at a rate of 12.1% (6.1%-18.2%, CI 95%) every three days, being potentially associated with 24.8% (20.8-29.7%, CI 95%; 3177-4542 cases, CI 95%) of all COVID-19 cases in Portugal during this period. Our data supports population/epidemiological (founder) effects contributing to the Y839 variant superspread. The potential existence of selective advantage is also discussed, although experimental validation is required. Despite huge differences in genome sampling worldwide, SARS-CoV-2 Spike D839Y has been detected in 13 countries in four continents, supporting the need for close surveillance and functional assays of Spike variants.


Subject(s)
COVID-19/epidemiology , COVID-19/transmission , Genome, Viral , Mutation , Pandemics , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics , COVID-19/diagnosis , COVID-19/virology , Epidemiological Monitoring , Genomics , High-Throughput Nucleotide Sequencing , Humans , Phylogeny , Portugal/epidemiology , SARS-CoV-2/classification , SARS-CoV-2/isolation & purification , Severity of Illness Index
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