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1.
Rev. panam. salud pública ; 45: e66, 2021. tab, graf
Article in English | LILACS | ID: biblio-1280511

ABSTRACT

ABSTRACT Objective. To evaluate the seroprevalence of COVID-19 infection in pauci-symptomatic and asymptomatic people, the associated epidemiological factors, and IgG antibody kinetic over a 5-month period to get a better knowledge of the disease transmissibility and the rate of susceptible persons that might be infected. Methods. Seroprevalence was evaluated by a cross-sectional study based on the general population of Santa Fe, Argentina (non-probabilistic sample) carried out between July and November 2020. A subgroup of 20 seropositive individuals was followed-up to analyze IgG persistence. For the IgG anti-SARS-CoV-2 antibodies detection, the COVID-AR IgG® ELISA kit was used. Results. 3 000 individuals were included conforming asymptomatic and pauci-symptomatic groups (n=1 500 each). From the total sample, only 8.83% (n=265) presented reactivity for IgG anti-SARS-CoV-2. A significant association was observed between positive anti-SARS-CoV-2 IgG and a history of contact with a confirmed case; the transmission rate within households was approximately 30%. In the pauci-symptomatic group, among the seropositive ones, anosmia and fever presented an OR of 16.8 (95% CI 9.5-29.8) and 2.7 (95% CI 1.6-4.6), respectively (p <0.001). In asymptomatic patients, IgG levels were lower compared to pauci-symptomatic patients, tending to decline after 4 months since the symptoms onset. Conclusion. We observed a low seroprevalence, suggestive of a large population susceptible to the infection. Anosmia and fever were independent significant predictors for seropositivity. Asymptomatic patients showed lower levels of antibodies during the 5-month follow-up. IgG antibodies tended to decrease over the end of this period regardless of symptoms.


RESUMEN Objetivo. Evaluar la seroprevalencia de la infección por el virus causante de la COVID-19 en personas paucisintomáticas y asintomáticas, los factores epidemiológicos asociados y la cinética de los anticuerpos IgG durante un período de cinco meses para conocer mejor la transmisibilidad de la enfermedad y la tasa de personas susceptibles a estar infectadas. Métodos. Se evaluó la seroprevalencia mediante un estudio transversal basado en la población general de Santa Fe, Argentina (muestra no probabilística) llevado a cabo entre julio y noviembre del 2020. Se realizó un seguimiento de un subgrupo de 20 personas seropositivas para analizar la persistencia de los anticuerpos IgG. Para la detección de los anticuerpos IgG contra SARS-COV-2, se empleó el kit ELISA COVID-AR IgG®. Resultados. Hubo 3 000 participantes divididos en un grupo asintomático y un grupo paucisintomático (n=1 500 cada grupo). De la muestra total, solo 8,83% (n=265) presentó una reactividad de IgG contra el SARS-CoV-2. Se observó una asociación significativa entre anticuerpos IgG positivos contra el SARS-CoV-2 y antecedente de contacto con un caso confirmado. La tasa de transmisión en el hogar fue de 30% aproximadamente. En el grupo paucisintomático, entre las personas seropositivas, la anosmia y la fiebre presentaron un OR de 16,8 (IC 95% 9,5-29,8) y 2,7 (IC 95% 1,6-4,6), respectivamente (p <0,001). En los pacientes asintomáticos, los niveles de IgG fueron inferiores en comparación con los pacientes paucisintomáticos, con tendencia a la baja pasados cuatro meses desde la aparición de los síntomas. Conclusiones. Se observó una seroprevalencia baja, indicadora de una gran población susceptible a la infección. La anosmia y la fiebre fueron factores predictivos independientes de relevancia para la seropositividad. Los pacientes asintomáticos mostraron niveles inferiores de anticuerpos durante el seguimiento de cinco meses. Los anticuerpos IgG tendieron a disminuir hacia el final del período con independencia de los síntomas.


RESUMO Objetivo. Avaliar a soroprevalência de anticorpos contra a COVID-19 em indivíduos paucissintomáticos e assintomáticos, os fatores epidemiológicos associados e a cinética dos anticorpos da classe IgG em um período de 5 meses, visando aprimorar o conhecimento sobre a transmissibilidade da doença e a taxa de suscetíveis à infecção. Métodos. Inquérito transversal de soroprevalência realizado na população geral (amostra não probabilística) de Santa Fé, na Argentina, entre julho e novembro de 2020. Um subgrupo de 20 indivíduos soropositivos foi acompanhado para analisar a persistência de anticorpos IgG. O kit de ensaio imunoenzimático (ELISA) COVID-AR IgG® foi usado para a detecção de anticorpos IgG contra SARS-CoV-2. Resultados. A amostra compreendeu 3 000 indivíduos, divididos entre assintomáticos e paucissintomáticos (n = 1.500 por grupo). Deste total, somente 8,83% (n = 265) apresentaram reatividade, com a detecção de anticorpos IgG contra SARS-CoV-2. Observou-se uma associação significativa entre a presença de anticorpos IgG contra SARS-CoV-2 e histórico de contato com caso confirmado. A taxa de transmissão intradomiciliar foi de aproximadamente 30%. No grupo paucissintomático, entre os soropositivos, o odds ratio (OR) para anosmia foi de 16,8 (IC 95% 9,5-29,8), e para febre, 2,7 (IC 95% 1,6-4,6) (p <0,001). Os indivíduos assintomáticos apresentaram níveis de IgG mais baixos que os paucissintomáticos, com uma tendência de declínio após 4 meses do início dos sintomas. Conclusões. Observou-se uma soroprevalência baixa de anticorpos contra a COVID-19 na população estudada, o que indica um grande número de pessoas suscetíveis à infecção. Anosmia e febre foram preditores importantes independentes de soropositividade. Os assintomáticos apresentaram níveis mais baixos de anticorpos aos 5 meses de acompanhamento. Houve uma tendência de redução dos anticorpos IgG ao final deste período, independentemente da presença de sintomas.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Carrier State/epidemiology , COVID-19/diagnosis , COVID-19/epidemiology , Argentina/epidemiology , Immunoglobulin G/blood , Enzyme-Linked Immunosorbent Assay , Seroepidemiologic Studies , Cross-Sectional Studies , COVID-19 Serological Testing , Anosmia/virology
2.
Rev. Assoc. Med. Bras. (1992) ; 66(6): 824-829, June 2020. tab
Article in English | LILACS, SES-SP | ID: biblio-1136280

ABSTRACT

SUMMARY OBJECTIVE To describe the concentration of total and specific IgG antibodies anti-Streptococcus B, anti-lipopolysaccharide of Klebsiella spp, and anti-lipopolysaccharide of Pseudomonas spp in the umbilical cord of newborn(NB) twins and to analyze the association between neonatal infection and antibody concentration in the umbilical cord blood. METHODS A prospective cross-sectional study of a cohort of NB twins admitted during the period of 20 months. Patients with malformations and mothers with infection were excluded. Variables analyzed: gestational age(GA); birth weight(BW); antibody concentrations in umbilical cord blood; infection episodes. We used the paired Student t-test, Spearman correlation, and generalized estimation equation. RESULTS 57 pairs of twins were included, 4 excluded, making the sample of 110 newborns. GA=36±1.65weeks and BW=2304.8±460g(mean±SD). Antibody concentrations in twins(mean±SD): total IgG=835.71±190.73mg/dL, anti-StreptococcusB IgG=250.66±295.1 AU/mL, anti-lipopolysaccharide of Pseudomonas spp IgG=280.04±498.66 AU/mL and anti-lipopolysaccharide of Klebsiella spp IgG=504.75±933.93 AU/mL. There was a positive correlation between maternal antibody levels and those observed in newborns(p <0.005). The transplacental transfer of maternal total IgG and anti-LPS Pseudomonas IgG antibodies was significantly lower at NB GA <34 weeks(p <0.05). Five newborns were diagnosed with an infection. Infants with infection had significantly lower total IgG concentration(p <0.05). CONCLUSION This study showed a positive correlation between maternal and newborn antibodies levels. In infants younger than 34 weeks there is less transfer of total IgG and anti-LPS Pseudomonas IgG. The highest incidence of infection in the newborn group who had significantly lower total IgG serum antibodies reinforces the importance of anti-infectious protection afforded by passive immunity transferred from the mother.


RESUMO OBJETIVOS Descrever o título de anticorpos IgG total e específico anti-Streptococcus B, anti-lipopolissacarídeos(LPS) de Klebsiella e Pseudomonas no cordão umbilical em gêmeos e analisar a possível associação entre os títulos desses anticorpos e a ocorrência de infecção. MÉTODOS Estudo prospectivo transversal de uma coorte de recém-nascidos (RN) gemelares em 20 meses. Excluídos: malformação, infecção congênita ou materna. Variáveis estudadas: idade gestacional(IG); peso de nascimento(PN); título de anticorpos e episódios de infecção. Foram utilizados testes t-Student pareado, correlação de Spearman e equações de estimação generalizadas. RESULTADOS Elegíveis 59 pares de gêmeos, excluídos 4 e incluídos 55 pares (n=110RN). A IG foi 36±1,65semanas e o PN foi 2304,8±460g (média±DP). Concentrações de anticorpos dos RN(média±DP): IgG total=835,71±190,73 mg/dL, IgG anti-Streptococcus B=295,1±250,66 UA/mL, IgG anti-LPS Pseudomonas=280,04±498,66 UA/mL e IgG anti-LPS Klebsiella=504,75± 933,93UA/mL. Houve correlação positiva entre níveis de anticorpos maternos e aqueles observados nos RN (p<0,005). A transferência transplacentária de anticorpos maternos IgG total e IgG anti-LPS Pseudomonas foi significativamente menor em RN IG < 34semanas (p<0,05). Foram diagnosticados 5 RN com infecção. Os RN que apresentaram infecção tinham concentração de IgG total significativamente menor (p<0,05). CONCLUSÕES Na população estudada existe correlação entre os anticorpos maternos e os níveis de anticorpos no RN. Nos gêmeos menores que 34 semanas há menor transferência de IgG total e IgG anti-LPS Pseudomonas. Nos RN com infecção a concentração de IgG total é significativamente menor, o que demonstra a maior vulnerabilidade e risco de infecção dessa população e a importância da imunidade passiva transferida pela placenta.


Subject(s)
Humans , Infant, Newborn , Infant , Pseudomonas Infections/blood , Streptococcal Infections/blood , Immunoglobulin G/blood , Klebsiella , Pseudomonas , Cross-Sectional Studies , Prospective Studies , Immunity, Maternally-Acquired , Infections
3.
Braz. j. infect. dis ; 24(1): 1-6, Feb. 2020. tab, graf
Article in English | LILACS | ID: biblio-1089330

ABSTRACT

ABSTRACT Febrile illnesses in developing countries are often misdiagnosed as malaria or typhoid fever. Although arboviral infections have similar clinical symptoms, they are usually not screened because of limited resources and the fact that there are several viruses in this group. Chikungunya virus (CHIKV) has been isolated in parts of Nigeria, but there is no documented evidence of the infection in Kogi State. This study determined seroprevalence of active and past CHIKV infection among febrile patients who tested negative for malaria and typhoid fever. Sera from 243 febrile patients were screened for CHIKV IgG and IgM using an immunochromatographic test kit. Clinical and socio-demographic variables were collected using a structured questionnaire. Recent CHIKV infection was observed in 5.8% of the study participants while 25.1% had IgG antibodies demonstrating previous infection. Significant associations were observed between seropositivity and age of participants (p < 0.001), sex (p = 0.044), marital status (p = 0.002), and occupation (p < 0.001). Clinical symptoms such as fever, joint pain, and headache were significantly associated with seropositivity. This study identified recent CHIKV infection in Anyigba. Therefore, there is need for routine screening of febrile patients and molecular characterization to determine the nature of circulating strains.


Subject(s)
Humans , Male , Female , Child , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Young Adult , Chikungunya Fever/epidemiology , Reference Values , Socioeconomic Factors , Immunoglobulin G/immunology , Immunoglobulin G/blood , Immunoglobulin M/blood , Immunoassay , Seroepidemiologic Studies , Chikungunya virus/immunology , Prevalence , Cross-Sectional Studies , Sex Distribution , Age Distribution , Fever/epidemiology , Chikungunya Fever/immunology , Antibodies, Viral/blood , Nigeria/epidemiology
4.
Frontiers of Medicine ; (4): 746-751, 2020.
Article in English | WPRIM | ID: wpr-880959

ABSTRACT

The ongoing pandemic of Coronavirus disease 19 (COVID-19) is caused by a newly discovered β Coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). How long the adaptive immunity triggered by SARS-CoV-2 can last is of critical clinical relevance in assessing the probability of second infection and efficacy of vaccination. Here we examined, using ELISA, the IgG antibodies in serum specimens collected from 17 COVID-19 patients at 6-7 months after diagnosis and the results were compared to those from cases investigated 2 weeks to 2 months post-infection. All samples were positive for IgGs against the S- and N-proteins of SARS-CoV-2. Notably, 14 samples available at 6-7 months post-infection all showed significant neutralizing activities in a pseudovirus assay, with no difference in blocking the cell-entry of the 614D and 614G variants of SARS-CoV-2. Furthermore, in 10 blood samples from cases at 6-7 months post-infection used for memory T-cell tests, we found that interferon γ-producing CD4


Subject(s)
Adaptive Immunity/physiology , Adult , Aged , Antibodies, Neutralizing/blood , COVID-19/immunology , Cohort Studies , Female , Humans , Immunoglobulin G/blood , Male , Middle Aged , SARS-CoV-2/immunology , T-Lymphocytes/physiology , Time Factors , Viral Proteins/immunology
5.
Article in English | WPRIM | ID: wpr-880737

ABSTRACT

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which first affected humans in China on December 31, 2019 (Shi et al., 2020). Coronaviruses generally cause mild, self-limiting upper respiratory tract infections in humans, such as the common cold, pneumonia, and gastroenteritis (To et al., 2013; Berry et al., 2015; Chan et al., 2015). According to the Report of the World Health Organization (WHO)-China Joint Mission on COVID-19 (WHO, 2020), the case fatality rate of COVID-19 increases with age, while the rate among males is higher than that among females (4.7% and 2.8%, respectively). Since an effective vaccine and specific anti-viral drugs are still under development, passive immunization using the convalescent plasma (CP) of recovered COVID-19 donors may offer a suitable therapeutic strategy for severely ill patients in the meantime. So far, several studies have shown therapeutic efficacy of CP transfusion in treating COVID-19 cases. A pilot study first reported that transfusion of CP with neutralizing antibody titers above 1:640 was well tolerated and could potentially improve clinical outcomes through neutralizing viremia in severe COVID-19 cases (Chen et al., 2020). Immunoglobulin G (IgG) and IgM are the most abundant and important antibodies in protecting the human body from viral attack (Arabi et al., 2015; Marano et al., 2016). Our study aimed to understand the aspects of plasma antibody titer levels in convalescent patients, as well as assessing the clinical characteristics of normal, severely ill, and critically ill patients, and thus provide a basis for guiding CP therapy. We also hoped to find indicators which could serve as a reference in predicting the progression of the disease.


Subject(s)
Adult , Aged , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19/therapy , China , Female , Humans , Immunization, Passive , Immunoglobulin G/blood , Immunoglobulin M/blood , Male , Middle Aged
6.
Cad. Saúde Pública (Online) ; 36(1): e00149119, 2020. tab
Article in English | LILACS | ID: biblio-1055626

ABSTRACT

Abstract: Varicella in adults and immunocompromised patients can be severe. The clinical diagnosis of varicella has high accuracy and the history of disease has a high positive predictive value for protection. A significant portion of adults, however, cannot remember if they have had varicella, especially older individuals. We conducted a cross-sectional study to determine the seroprevalence of varicella protective antibodies titers in adults with no clinical history of disease, attended at a Reference Center for Special Immunobiologicals and Travel Medicine in Rio de Janeiro (Brazil). Titration of immunoglobulin G (IgG) antibodies to varicella-zoster was determined by chemiluminescence immunoassay. Among 140 adults without history of varicella, 92% had protective antibody titers. We concluded that seroprevalence of varicella-zoster protection was very high in adults with negative history of disease and the use of serology before vaccination reduced significantly unnecessary vaccine and immunoglobulin use.


Resumo: A varicela é uma doença potencialmente grave em adultos e em pacientes imunocomprometidos. O diagnóstico clínico da varicela apresenta alta acurácia, e o relato da doença na história individual tem alto valor preditivo positivo para a proteção. Entretanto, uma proporção significativa de adultos, principalmente os mais idosos, não se lembra se já teve a doença. Realizamos um estudo transversal para determinar a soroprevalência de títulos protetores de anticorpos contra a varicela em adultos sem história clínica da doença, atendidos em um Centro de Referência para Imunobiológicos Especiais e Medicina de Viagem no Rio de Janeiro, Brasil. Os títulos da imunoglobulina G (IgG) contra varicela-zoster foram determinados por quimiluminescência. Entre 140 adultos sem história de varicela, 92% apresentaram títulos protetores de anticorpos. Concluímos que a soroprevalência de proteção contra varicela-zoster é muito alta em adultos sem história da doença, e que o uso de teste sorológico antes da vacinação reduziria significativamente a vacinação desnecessária e o uso de imunoglobulina.


Resumen: La varicela en adultos y pacientes inmunocomprometidos puede ser grave. El diagnóstico clínico de la varicela tiene una gran precisión y la historia de la enfermedad cuenta con un alto valor predictivo positivo para la protección contra ella. Sin embargo, un porcentaje significativo de adultos, no puede recordar si tuvieron varicela, especialmente las personas más viejas. Realizamos un estudio transversal para determinar la seroprevalencia de las concentraciones de anticuerpos protectores frente a la varicela, en adultos sin historia clínica de la enfermedad, que se llevó a cabo en un Centro de Referencia para Inmunobiología Especial y Medicina del Viajero en Río de Janeiro (Brasil). Se determinó la valoración de los anticuerpos de inmunoglobulina G (IgG) a la varicela-zoster mediante un ensayo inmunológico quimioluminiscente. Entre 140 adultos sin historial de varicela, un 92% tuvieron concentraciones de anticuerpos protectores. Concluimos que la seroprevalencia de la protección a la varicela-zoster fue muy alta en adultos con un historial negativo de la enfermedad y la utilización de la serología antes de la vacunación redujo de manera significativa la vacunación innecesaria y el uso de la inmunoglobulina.


Subject(s)
Humans , Adult , Immunoglobulin G/blood , Chickenpox/epidemiology , Herpesvirus 3, Human/immunology , Measurements, Methods and Theories , Brazil/epidemiology , Chickenpox/prevention & control , Chickenpox/blood , Prevalence , Cross-Sectional Studies , Chickenpox Vaccine , Luminescent Measurements , Antibodies, Viral/blood
7.
Rev. bras. parasitol. vet ; 29(1): e014919, 2020. tab, graf
Article in English | LILACS | ID: biblio-1092692

ABSTRACT

Abstract This study investigated the seropositivity for five different tick-borne agents, namely Anaplasma marginale, Babesia bovis, Babesia bigemina, Coxiella burnetii, Anaplasma phagocytophilum, and Trypanosoma vivax in beef cattle in the Brazilian Pantanal. The serum samples collected from animals (200 cows; 200 calves) were used in indirect enzyme-linked immunosorbent assays (iELISA) to detect IgG antibodies against A. marginale, B. bovis, B. bigemina, and T. vivax, and Indirect Fluorescent Antibody Test (IFAT) for detecting IgG antibodies against C. burnetii and A. phagocytophilum. No correlation was observed between seropositivity for C. burnetii and A. phagocytophilum with other agents whereas moderate correlation was observed for A. marginalexB. bigemina x B. bovis. Cows were more seropositive for T. vivax whereas calves were more seropositive for B. bovis and B. bigemina. The highest number of seropositive animals by a single agent was observed for T. vivax (15.2%). Co-seropositivity for T. vivax + A. marginale was higher in cows (25.5%) and for T. vivax + B. bovis + B. bigemina + A. marginale was higher in calves (57.5%). The high seropositivity correlation for A. marginale x B. bovis x B. bigemina is probably due to the presence of the tick biological vector, Rhipicephalus microplus, in the studied farms. Common transmission pathways, mediated by hematophagous dipterans and fomites, may explain the high co-seropositivity of cows for A. marginale and T. vivax. Low seropositivity to C. burnetii is probably due to the type of breeding system employed (extensive). Seropositivity for A. phagocytophilum in only one animal suggests the occurrence of a cross-serological reaction with another agent of the genus Anaplasma.


Resumo Este estudo teve como objetivo determinar a co-soropositividade para agentes transmitidos por carrapatos, como Anaplasma marginale, Babesia bovis, Babesia bigemina, Coxiella burnetii, Anaplasma phagocytophilum, e Trypanosoma vivax em bovinos de corte do Pantanal Brasileiro. Amostras de soro foram colhidas de 400 animais (200 vacas; 200 bezerros) e submetidas a Ensaios Imunoenzimáticos Indiretos (iELISA) para detecção de anticorpos IgG anti- A. marginale, anti- B. bovis, anti- B. bigemina e anti- T. vivax, e à Reação de Imunofluorescência Indireta (RIFI) para detecção de anticorpos IgG anti -C. burnetii e anti- A. phagocytophilum. Ausência de correlação foi vista entre os animais soropositivos para C. burnetii e A. phagocytophilum com os outros agentes e correlação moderada ocorreu entre A. marginale x B. bigemina x B. bovis. Vacas foram mais soropositivas que bezerros para T. vivax e bezerros mais soropositivos que vacas para B. bovis e B. bigemina. Maior número de animais soropositivos para um único agente foi visto para T. vivax (15,2%). Vacas demonstraram maior co-soropositividade para T. vivax + A. marginale (25,5%) e bezerros para T. vivax + B. bovis + B. bigemina + A. marginale (57,5%). A alta correlação entre a soropositividade para A. marginale x B. bovis x B. bigemina é provavelmente devida à presença do vetor biológico, o carrapato Rhipicephalus microplus, nas fazendas estudadas. As vias de transmissão comuns, mediadas por dípteros hematófagos e fômites, podem explicar a alta co-soropositividade das vacas para A. marginale e T. vivax. A baixa soropositividade para C. burnetii é provavelmente devida ao tipo de sistema de criação empregado (extenso). A soropositividade para A. phagocytophilum em apenas um animal sugere a ocorrência de reação sorológica cruzada com outro agente do gênero Anaplasma.


Subject(s)
Animals , Cattle , Immunoglobulin G/blood , Antibodies, Protozoan/blood , Cattle Diseases/microbiology , Cattle Diseases/parasitology , Tick-Borne Diseases/microbiology , Tick-Borne Diseases/parasitology , Antibodies, Bacterial/blood , Enzyme-Linked Immunosorbent Assay
9.
Clinics ; 75: e2212, 2020. tab, graf
Article in English | LILACS | ID: biblio-1133408

ABSTRACT

Serologic testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) promises to assist in assessing exposure to and confirming the diagnosis of coronavirus disease 2019 (COVID-19), and to provide a roadmap for reopening countries worldwide. Considering this, a proper understanding of serologic-based diagnostic testing characteristics is critical. The aim of this study was to perform a structured systematic review and meta-analysis to evaluate the diagnostic characteristics of serological-based COVID-19 testing. Electronic searches were performed using Medline (PubMed), EMBASE, and Cochrane Library. Full-text observational studies that reported IgG or IgM diagnostic yield and used nucleic acid amplification tests (NAATs) of respiratory tract specimens, as a the reference standard in English language were included. A bivariate model was used to compute pooled sensitivity, specificity, positive/negative likelihood ratio (LR), diagnostic odds ratio (OR), and summary receiver operating characteristic curve (SROC) with corresponding 95% confidence intervals (CIs). Five studies (n=1,166 individual tests) met inclusion criteria. The pooled sensitivity, specificity, and diagnostic accuracy for IgG was 81% [(95% CI, 61-92);I2=95.28], 97% [(95% CI, 78-100);I2=97.80], and 93% (95% CI, 91-95), respectively. The sensitivity, specificity, and accuracy for IgM antibodies was 80% [(95% CI, 57-92);I2=94.63], 96% [(95% CI, 81-99);I2=92.96] and 95% (95% CI, 92-96). This meta-analysis demonstrates suboptimal sensitivity and specificity of serologic-based diagnostic testing for SARS-CoV-2 and suggests that antibody testing alone, in its current form, is unlikely to be an adequate solution to the difficulties posed by COVID-19 and in guiding future policy decisions regarding social distancing and reopening of the economy worldwide.


Subject(s)
Humans , Pneumonia, Viral/diagnosis , Serologic Tests , Coronavirus Infections/diagnosis , Antibodies, Viral/blood , Immunoglobulin G/blood , Immunoglobulin M/blood , Sensitivity and Specificity , Clinical Laboratory Techniques , Pandemics , Betacoronavirus , COVID-19 Testing , SARS-CoV-2 , COVID-19
10.
Rev. saúde pública (Online) ; 54: 69, 2020. tab, graf
Article in English | LILACS, BBO | ID: biblio-1127233

ABSTRACT

ABSTRACT OBJECTIVE To estimate the seroprevalence of antibodies to SARS-CoV-2 among blood donors in the state of Rio de Janeiro, Brazil. METHODS Data were collected on 2,857 blood donors from April 14 to 27, 2020. This study reports crude prevalence of antibodies to SARS-CoV-2, population weighted prevalence for the state, and prevalence adjusted for test sensitivity and specificity. Logistic regression models were used to establish the correlates of SARS-CoV-2 prevalence. For the analysis, we considered collection period and site, sociodemographic characteristics, and place of residence. RESULTS The proportion of positive tests for SARS-Cov-2, without any adjustment, was 4.0% (95%CI 3.3-4.7%), and the weighted prevalence was 3.8% (95%CI 3.1-4.5%). We found lower estimates after adjusting for test sensitivity and specificity: 3.6% (95%CI 2.7-4.4%) for the non-weighted prevalence, and 3.3% (95%CI 2.6-4.1%) for the weighted prevalence. Collection period was the variable most significantly associated with crude prevalence: the later the period, the higher the prevalence. Regarding sociodemographic characteristics, the younger the blood donor, the higher the prevalence, and the lower the education level, the higher the odds of testing positive for SARS-Cov-2 antibody. We found similar results for weighted prevalence. CONCLUSIONS Our findings comply with some basic premises: the increasing trend over time, as the epidemic curve in the state is still on the rise; and the higher prevalence among both the youngest, for moving around more than older age groups, and the less educated, for encountering more difficulties in following social distancing recommendations. Despite the study limitations, we may infer that Rio de Janeiro is far from reaching the required levels of herd immunity against SARS-CoV-2.


Subject(s)
Humans , Male , Female , Adult , Aged , Young Adult , Pneumonia, Viral/immunology , Blood Donors/statistics & numerical data , Coronavirus Infections/immunology , Betacoronavirus/immunology , Antibodies, Viral/blood , Pneumonia, Viral/blood , Pneumonia, Viral/epidemiology , Brazil/epidemiology , Immunoglobulin G/blood , Immunoglobulin M/blood , Seroepidemiologic Studies , Prevalence , Cross-Sectional Studies , Regression Analysis , Sensitivity and Specificity , Coronavirus Infections/blood , Coronavirus Infections/epidemiology , Pandemics , SARS-CoV-2 , COVID-19 , Middle Aged
11.
Rev. Soc. Bras. Med. Trop ; 53: e20190132, 2020. tab, graf
Article in English | LILACS | ID: biblio-1057283

ABSTRACT

Abstract INTRODUCTION: In Colombia, there is insufficient epidemiological surveillance of zoonotic hemorrhagic viruses. METHODS: We performed a sero-epidemiological study in indigenous populations of Wayuü, Kankuamos, and Tuchin communities using Maciel hantavirus and Junin arenavirus antigens for IgG detection by ELISA. RESULTS IgG antibodies to hantavirus and arenavirus were found in 5/506 (1%) and 2/506 (0.4%) serum samples, respectively. CONCLUSIONS: Arenavirus and hantavirus circulate in indigenous populations from the Colombian Caribbean region, and the results indicate that the indigenous populations are exposed to these zoonotic agents, with unknown consequences on their health, despite low seroprevalence.


Subject(s)
Humans , Male , Female , Adult , Immunoglobulin G/blood , Indians, South American , Hantavirus/immunology , Arenavirus/immunology , Arenaviridae Infections/epidemiology , Hantavirus Infections/epidemiology , Antibodies, Viral/blood , Enzyme-Linked Immunosorbent Assay , Seroepidemiologic Studies , Cross-Sectional Studies , Risk Factors , Colombia/epidemiology , Arenaviridae Infections/diagnosis , Hantavirus Infections/diagnosis
12.
Rev. Soc. Bras. Med. Trop ; 53: e20190181, 2020. graf
Article in English | LILACS | ID: biblio-1092205

ABSTRACT

Abstract INTRODUCTION: Human herpesvirus (HHV)-7 establishes a latent infection during the lifetime of the host and can reactivate after the primary infection, leading to lytic replication in immunosuppressed patients. METHODS: This study aimed to develop an enzyme-linked immunosorbent assay (ELISA) to identify HHV-7 serum antibodies and compare its performance with that of an indirect immunofluorescence assay (IFA). RESULTS: Serum samples (n=102) were tested by IgG-IFA and by ELISA. IFA and ELISA showed IgG-positive results in 77 and 73 samples, respectively. Qualitative concordance of 96% was demonstrated between the two techniques. CONCLUSIONS: ELISA may be useful to diagnose HHV-7 infection.


Subject(s)
Humans , Immunoglobulin G/blood , Herpesvirus 7, Human/immunology , Roseolovirus Infections/diagnosis , Antibodies, Viral/blood , Enzyme-Linked Immunosorbent Assay , ROC Curve , Sensitivity and Specificity , Fluorescent Antibody Technique, Indirect
13.
Rev. Soc. Bras. Med. Trop ; 53: e20190164, 2020. tab
Article in English | LILACS | ID: biblio-1092214

ABSTRACT

Abstract INTRODUCTION Toxoplasmosis is a zoonosis caused by Toxoplasma gondii. This study investigated the prevalence and factors associated with toxoplasmosis among pregnant women. METHODS We followed an analytical observational study. From July 2016 to June 2017, 218 pregnant women were selected. The infection was detected through serological dosage of anti-T.gondii Immunoglobulin(Ig) M and IgG antibodies. RESULTS The seroprevalence was 35.8%; the factors associated with infection were consumption of non-drinking water, residence in an urban area, and threatened abortion during the current pregnancy. CONCLUSIONS The seroprevalence of toxoplasmosis among pregnant women is high. The risk factors are dependent on environmental determinants.


Subject(s)
Humans , Female , Pregnancy , Adult , Antibodies, Protozoan/blood , Toxoplasmosis/epidemiology , Pregnancy Complications, Parasitic/parasitology , Pregnancy Complications, Parasitic/epidemiology , Peru/epidemiology , Socioeconomic Factors , Immunoglobulin G/blood , Immunoglobulin M/blood , Seroepidemiologic Studies , Toxoplasmosis/diagnosis , Prevalence , Risk Factors , Pregnancy Complications, Parasitic/diagnosis
14.
Adv Rheumatol ; 60: 38, 2020. tab
Article in English | LILACS | ID: biblio-1130782

ABSTRACT

Abstract Background: Annexins are a group of conserved proteins which exert several regulatory functions on various cellular activities. Increased frequency and levels of antibodies against annexin V have already been observed in several autoimmune diseases including systemic sclerosis (SSc), but their role as a vascular biomarker is unknown. The aim of this study was to determine the serum levels and the dynamical behavior of anti-annexin V antibodies over a 24 months follow-up in patients with SSc. Methods: In this bicentric cross-sectional study, 70 patients with SSc were consecutively selected from March 2016 to April 2017. Demographic and clinical features, including the presence of active DUs, were collected. Serum anti-annexin V IgG and IgM antibodies were measured at baseline and after 6, 12 and 24 months of follow-up. Videocapillaroscopy was performed in all patients. Results: Among the 70 SSc patients included anti-annexin V IgG was found in 11 patients (15.7%) (range of 15.88-39.48 U/mL) and anti-annexin V IgM in 10 patients (14.3%) (range of 14.16-22.69 U/mL) at baseline. During follow-up, the number of patients who were positive for anti-annexin V IgG and IgM remained stable over 24 months. Among the patients with positive anti-annexin V IgG at baseline the frequency of patients with necrosis or amputation of extremities, forced vital capacity less than 70% and pulmonary arterial hypertension (PAH) was significantly higher than in patients with negative anti-annexin V IgG antibodies. Patients with anti-annexin V IgG had also a higher Raynaud's Condition Score and a higher Health Assessment Questionnaire Disability Index (HAQ-DI) than patients without these antibodies at baseline. Patients with positive anti-annexin V IgM at baseline presented a higher frequency of PAH, compared to those with negative anti-annexin V IgM at baseline. Conclusions: Anti-annexin V antibodies are stable and do not change their positivity during a 24 month follow-up in SSc patients. Anti-annexin V IgG was associated with more severe interstitial lung involvement and digital microangiopathy, and patients with anti-annexin V IgG or IgM had a higher occurrence of PAH indicating an association of these biomarker with more severe disease.(AU)


Subject(s)
Humans , Scleroderma, Systemic/physiopathology , Immunoglobulin G/blood , Biomarkers/analysis , Annexin A5/blood , Cross-Sectional Studies/instrumentation , Microscopic Angioscopy/instrumentation
15.
Medicina (B.Aires) ; 79(6): 433-437, dic. 2019. graf, tab
Article in Spanish | LILACS | ID: biblio-1056749

ABSTRACT

Se analizó; de forma retrospectiva la presencia de anticuerpos só;©ricos IgG e IgM anti-Toxoplasma gondii en las embarazadas que concurrieron a siete hospitales del ó;rea Metropolitana de Buenos Aires durante 2006 y 2017. La prevalencia de infecció;n, medida como presencia de anticuerpos, en 2006 vs. 2017, fue: Hospital Alemán: 22 y 17% (p = 0.004), Hospital Fiorito: 44 y 33% (p < 0.001), Hospital Gandulfo: 30 y 34% (p 0.025), Hospital Grierson: 60 y 44% (p < 0.001), Hospital Rivadavia: 59 y 51% (p=0.003), Maternidad Sardá 47 y 39% (p < 0.001) y Hospital Thompson: 61 y 51% (p < 0.001). La comparació;n demostró; una disminució;n estadísticamente significativa de la seroprevalencia en seis hos pitales. Tambín disminuyeron significativamente la reactividad para IgM en 2017 respecto de 2006 y la seroprevalencia para T. gondii en el total de la població;n de embarazadas estudiadas, lo que significa un mayor nó;ºmero de mujeres susceptible de desarrollar infecció;n aguda durante el embarazo.


We analyzed the presence of IgG and IgM anti- Toxoplasma gondii, as a measure of infection, in pregnant women attending seven hospitals in the Metropolitan Area of Buenos Aires during 2006 and 2017. T. gondii seroprevalence in 2006 vs. 2017, was: Hospital Alemán: 22 and 17% (p = 0.004), Hospital Fiorito: 44 and 33% (p < 0.001), Hospital Gandulfo: 30 and 34% (p 0.025), Hospital Grierson 60 and 44% (p < 0.001), Hospital Rivadavia: 59 and 51% (p = 0.003), Hospital Sardá: 47 and 39% (p < 0. 001), and Hospital Thompson: 61 and 51% (p < 0.001). The comparison showed a significant decrease in seroprevalence in six hospitals. We also observed a significant decrease in the reactivity for IgM in 2017 compared to 2006 and in the seroprevalence for T. gondii in the overall population of pregnant women in the study. This means that a greater number of women are susceptible to develop acute infection during pregnancy.


Subject(s)
Humans , Female , Pregnancy , Adult , Middle Aged , Young Adult , Pregnancy Complications, Infectious/immunology , Toxoplasma/immunology , Antibodies, Protozoan/blood , Toxoplasmosis/immunology , Argentina/epidemiology , Pregnancy Complications, Infectious/epidemiology , Time Factors , Immunoglobulin G/blood , Immunoglobulin M/blood , Antibodies, Protozoan/immunology , Seroepidemiologic Studies , Toxoplasmosis/blood , Toxoplasmosis/epidemiology , Retrospective Studies , Risk Factors , Age Distribution , Hospitals/statistics & numerical data
16.
Rev. bras. parasitol. vet ; 28(3): 518-521, July-Sept. 2019. tab, graf
Article in English | LILACS | ID: biblio-1042525

ABSTRACT

Abstract The objective of this study was to report an outbreak of human toxoplasmosis at a research institution in Londrina, Paraná, from December 2015 to February 2016. Blood samples from 26 symptomatic individuals were collected and the microparticle chemiluminescence immunoassay was performed to detect IgM, IgG and specific IgG avidity test in the official laboratory. A total of 20 people with symptoms and serology compatible with acute toxoplasmosis (IgM positive and IgG with low avidity) were selected as cases, while 45 asymptomatic employees working in the same teams and during the same shifts were selected as controls. All the participants of the investigation answered an epidemiological questionnaire. Three samples of water and one sludge from the institution's supply cisterns, 10 soil samples, 11 plant samples, three cat fecal samples and one domestic feline cadaver were collected for analysis of the polymerase chain reaction (PCR) for T. gondii. After analyzing the epidemiological data, the consumption of vegetables in the restaurant of the institution was the only variable associated with the occurrence of the disease. In laboratory results, all the samples showed negative results to PCR. The rapid recognition of the outbreak, early notification and investigation could have broken the chain of transmission early, thus preventing the emergence of new cases. In addition, the adoption of good food handling practices could have prevented the occurrence of the outbreak.


Resumo O objetivo deste estudo foi relatar um surto de toxoplasmose humana em uma instituição de pesquisa em Londrina, Paraná, no período de dezembro de 2015 a fevereiro de 2016. Amostras de sangue de 26 indivíduos sintomáticos foram coletadas e o imunoensaio de quimioluminescência de micropartículas foi realizado para detectar IgM, IgG e teste de avidez de IgG específica em laboratório oficial. Um total de 20 pessoas com sintomas e sorologia compatíveis com toxoplasmose aguda (IgM positiva e IgG com baixa avidez) foi selecionado como casos, enquanto 45 funcionários assintomáticos que trabalhavam nas mesmas equipes e durante os mesmos turnos foram utilizados como controles. Todos os participantes da investigação responderam a um questionário epidemiológico. Foram coletadas três amostras de água e uma de lodo das cisternas de abastecimento da instituição, 10 de solo, 11 de vegetais, três amostras de fezes de gato e um cadáver de filhote felino doméstico para detecção de T. gondii pela reação em cadeia da polimerase (PCR). Após análise dos dados epidemiológicos, o consumo de hortaliças no restaurante da instituição foi a única variável associada à ocorrência da doença. Em resultados laboratoriais, todas as amostras apresentaram resultados negativos a PCR. O rápido reconhecimento do surto, notificação e investigação prematura poderia ter quebrado a cadeia de transmissão, evitando assim o surgimento de novos casos. Além disso, a adoção de boas práticas de manipulação de alimentos poderia ter impedido a ocorrência do surto.


Subject(s)
Humans , Animals , Male , Female , Adult , Aged , Cats , Toxoplasma/immunology , Immunoglobulin G/blood , Immunoglobulin M/blood , Antibodies, Protozoan/blood , Toxoplasmosis/epidemiology , Disease Outbreaks , Brazil/epidemiology , Immunoassay , Case-Control Studies , Risk Factors , Luminescence , Middle Aged
17.
Rev. méd. Chile ; 147(5): 668-672, mayo 2019. tab, graf
Article in Spanish | LILACS | ID: biblio-1014277

ABSTRACT

Autoimmune pancreatitis is uncommon, responds to steroids and is usually associated with diabetes mellitus. We report a 73 year-old male who, two months after a diagnosis of diabetes mellitus, presented with obstructive jaundice and weight loss. Abdominal magnetic resonance imaging was suggestive of an autoimmune pancreatitis and serum IgG4 was 339 mg/dl (normal range 3-201). The patient was treated with prednisone 40 mg/day with a good clinical and laboratory response. During outpatient care, the dose of prednisone was tapered.


Subject(s)
Humans , Male , Aged , Prednisone/therapeutic use , Diabetes Complications/complications , Diabetes Complications/drug therapy , Diabetes Mellitus/drug therapy , Autoimmune Pancreatitis/complications , Autoimmune Pancreatitis/drug therapy , Glucocorticoids/therapeutic use , Immunoglobulin G/blood , Magnetic Resonance Imaging , Treatment Outcome , Autoimmune Pancreatitis/diagnostic imaging , Hypoglycemic Agents/therapeutic use , Insulin/therapeutic use
18.
Rev. bras. parasitol. vet ; 28(1): 161-163, Jan.-Mar. 2019. tab
Article in English | LILACS | ID: biblio-1042497

ABSTRACT

Abstract Neospora spp. are intracellular protozoa with worldwide distribution and closely related to Toxoplasma gondii, which can infect a variety of mammals including horses. From September 2013 to June 2014, 185 horses from northern, central and southern parts of mainland Portugal were randomly sampled and tested for detection of immunoglobulin (Ig) G antibodies to Neospora spp. using an indirect multi-species enzyme-linked immunosorbent assay (ELISA) commercial test (ID Screen® Neospora caninum Indirect Multi-species; ID.vet Innovative Diagnostics, Grabels, France). Two horses (1.1%; CI: 0.1-3.8%), one male and one female, were found to be seropositive for Neospora spp. Both seropositive animals were horses housed indoors but with access to outdoors, used for leisure activities and were apparently healthy, with good body condition and with no alterations at physical examination. This was the first serologic survey of antibodies to Neospora spp. carried out in horses from Portugal.


Resumo Neospora spp. são protozoários intracelulares com distribuição mundial e estreitamente relacionados com Toxoplasma gondii, que podem infectar uma variedade de mamíferos, incluindo cavalos. De setembro de 2013 a junho de 2014, 185 cavalos de áreas do Norte, Centro e Sul de Portugal continental foram aleatoriamente amostrados e testados para a detecção de anticorpos imunoglobulinas (Ig) G anti-Neospora spp., utilizando-se um ensaio imunoenzimático (ELISA) indireto multi-espécies comercial (ID Screen® Neospora caninum Indirect Multi-species; ID.vet Innovative Diagnostics, Grabels, France). Dois cavalos (1,1%; IC: 0,1-3,8%), um macho e uma fêmea, foram detectados como seropositivos para Neospora spp. Ambos os animais seropositivos eram cavalos mantidos em cocheiras mas com acesso aos piquetes, eram utilizados para atividades de lazer e estavam aparentemente saudáveis, com boa condição corporal e sem alterações ao exame físico. Essa é o primeiro rastreio de anticorpos para Neospora spp. realizado em cavalos de Portugal.


Subject(s)
Animals , Male , Female , Immunoglobulin G/blood , Antibodies, Protozoan/blood , Coccidiosis/veterinary , Neospora/microbiology , Horse Diseases/diagnosis , Horses/parasitology , Portugal , Enzyme-Linked Immunosorbent Assay , Coccidiosis/diagnosis , Fluorescent Antibody Technique, Indirect , Horse Diseases/parasitology
19.
Arq. neuropsiquiatr ; 77(1): 39-46, Jan. 2019. tab, graf
Article in English | LILACS | ID: biblio-983876

ABSTRACT

ABSTRACT Objective: We investigated the protective effect of the extract of the Camellia japonica L. flower on cerebral ischemia-reperfusion injury in rats. Methods: The rat ischemia-reperfusion injury was induced by middle cerebral artery occlusion for 90 minutes and reperfusion for 48 hours. The animals received an intravenous injection once a day of 20, 40, 80 mg/kg extract of C. japonica for three consecutive days before the ischemia reperfusion. The learning and memory function, the infarct volume, serum malondialdehyde (MDA) level and lactate dehydrogenase activity, and extravasation of immunoglobulin G (IgG) into cerebral parenchyma were assessed as the cell damage index. Results: Pretreatment with extract of C. japonica markedly reduced the infarct volume, serum malondialdehyde level and lactate dehydrogenase activity, and markedly inhibited the extravasation of IgG. Moreover, pretreatment with extract of C. japonica may also inhibit the learning and memory deficits induced by an ischemia-reperfusion injury. Conclusion: It was concluded that pretreatment with extract of C. japonica has a protective effect on cerebral ischemia-reperfusion injury in rats.


RESUMO Objetivo: Investigamos o efeito protetor do extrato da flor de Camellia japonica L. (ECJ) na lesão de reperfusão isquêmica cerebral (I/R) em ratos. Métodos: A lesão de I/R de rato foi induzida por uma oclusão da artéria cerebral média por 90 minutos e reperfusão por 48 horas. Os animais receberam uma injeção intravenosa uma vez ao dia de 20, 40, 80 mg/kg de ECJ por três dias consecutivos antes da I/R. A função de aprendizagem e memória, o volume do infarto, o nível sérico de malondialdeído (MDA), a atividade da desidrogenase láctica e o extravasamento de imunoglobulina (IgG) no parênquima cerebral foram avaliados como índices de dano celular. Resultados: O pré-tratamento com ECJ reduziu acentuadamente o volume do infarto, o nível sérico de MDA e a atividade da desidrogenase láctica, e inibiu marcadamente o extravasamento de IgG. Além disso, o pré-tratamento com ECJ também poderia inibir os déficits de aprendizado e memória induzidos pela lesão de I/R. Conclusão: O pré-tratamento com ECJ tem um efeito protetor contra lesão cerebral de I/R em ratos.


Subject(s)
Animals , Male , Female , Plant Extracts/pharmacology , Reperfusion Injury/prevention & control , Brain Ischemia/prevention & control , Neuroprotective Agents/pharmacology , Camellia/chemistry , Swimming/physiology , Time Factors , Immunoglobulin G/blood , Nimodipine/pharmacology , Random Allocation , Reproducibility of Results , Treatment Outcome , Rats, Sprague-Dawley , Disease Models, Animal , L-Lactate Dehydrogenase/analysis , Malondialdehyde/blood
20.
Mem. Inst. Oswaldo Cruz ; 114: e180448, 2019. tab, graf
Article in English | LILACS | ID: biblio-1040617

ABSTRACT

Anthropogenic environmental changes arising from settlement and agriculture include deforestation and replacement of natural vegetation by crops providing opportunities for pathogen spillover from animals to humans. This study aimed to investigate the prevalence of rodent-borne virus infections in seven rural settlements from Midwestern Brazil. Of the 466 individuals tested 12 (2.57%) were reactive for orthohantavirus and 3 (0.64%) for mammarenavirus. These rural settlers lived under unfavorable infrastructure, socioeconomic disadvantages, and unsanitary conditions, representing a risk for rodent-borne infections. Development of public policies towards the improvement of health, sanitation and awareness of rodent-borne diseases in improvised camps and settlements is imperative, in order to reduce morbidity and mortality caused by these diseases.


Subject(s)
Humans , Animals , Male , Female , Child, Preschool , Child , Adolescent , Adult , Aged , Aged, 80 and over , Young Adult , Rodentia/virology , Arenaviridae Infections/epidemiology , Hantavirus Infections/epidemiology , Disease Vectors/classification , Rodentia/classification , Rural Population , Socioeconomic Factors , Brazil/epidemiology , Immunoglobulin G/blood , Enzyme-Linked Immunosorbent Assay , Prevalence , Cross-Sectional Studies , Arenaviridae Infections/diagnosis , Arenaviridae Infections/transmission , Hantavirus Infections/diagnosis , Hantavirus Infections/transmission , Middle Aged , Antibodies, Viral/blood
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