Cycle Threshold Values of SARS-CoV-2 RT-PCR during Outbreaks in Nursing Homes: A Retrospective Cohort Study.

Backgound/Objectives: Cycle threshold (Ct) values of SARS-CoV-2 real-time reverse transcriptase-polymerase chain reaction (RT-PCR) tests are associated with infectivity and viral load, and they could be an aid in forecasting the evolution of SARS-CoV-2 outbreaks. The objective was to know the Ct values related to the incidence and reinfection of SARS-CoV-2 in successive outbreaks, which took place in nursing homes in Castellon (Spain) during 2020-2022, and to test its usefulness as an instrument of epidemic surveillance in nursing homes. METHODS: a retrospective cohort design with Poisson regression and multinomial logistic regression were used. RESULTS: We studied four nursing home SARS-CoV-2 outbreaks, and the average infection rate, reinfection rate, and case fatality were 72.7%, 19.9%, and 5.5%, respectively; 98.9% of residents were vaccinated with three doses of a mRNA SARS-CoV-2 vaccine. Ct values for first infections and reinfections were 27.1 ± 6.6 and 31.9 ± 5.4 (p = 0.000). Considering Ct values ≥ 30 versus <30, residents with reinfections had Ct values higher than residents with a first infection, an adjusted relative risk of 1.66 (95% Confidence interval 1.10-2.51). A sensitivity analysis confirmed these results. CONCLUSIONS: Reinfection and SARS-CoV-2 vaccination (hybrid immunity) could protect against severe disease better than vaccination alone. High Ct values suggest lower transmission and severity. Its value can be useful for surveillance and forecasting future SARS-CoV-2 epidemics.

Underreporting of Cases in the COVID-19 Outbreak of Borriana (Spain) during Mass Gathering Events in March 2020: A Cross-Sectional Study.

Determining the number of cases of an epidemic is the first function of epidemiological surveillance. An important underreporting of cases was observed in many locations during the first wave of the COVID-19 pandemic. To estimate this underreporting in the COVID-19 outbreak of Borriana (Valencia Community, Spain) in March 2020, a cross-sectional study was performed in June 2020 querying the public health register. Logistic regression models were used. Of a total of 468 symptomatic COVID-19 cases diagnosed in the outbreak through anti-SARS-CoV-2 serology, 36 cases were reported (7.7%), resulting in an underreporting proportion of 92.3% (95% confidence interval [CI], 89.5-94.6%), with 13 unreported cases for every reported case. Only positive SARS-CoV-2 polymerase chain reaction cases were predominantly reported due to a limited testing capacity and following a national protocol. Significant factors associated with underreporting included no medical assistance for COVID-19 disease, with an adjusted odds ratio [aOR] of 10.83 (95% CI 2.49-47.11); no chronic illness, aOR = 2.81 (95% CI 1.28-6.17); middle and lower social classes, aOR = 3.12 (95% CI 1.42-6.85); younger age, aOR = 0.97 (95% CI 0.94-0.99); and a shorter duration of illness, aOR = 0.98 (95% CI 0.97-0.99). To improve the surveillance of future epidemics, new approaches are recommended.

Cellular Immunity of SARS-CoV-2 in the Borriana COVID-19 Cohort: A Nested Case-Control Study.

Our goal was to determine the cellular immune response (CIR) in a sample of the Borriana COVID-19 cohort (Spain) to identify associated factors and their relationship with infection, reinfection and sequelae. We conducted a nested case-control study using a randomly selected sample of 225 individuals aged 18 and older, including 36 individuals naïve to the SARS-CoV-2 infection and 189 infected patients. We employed flow-cytometry-based immunoassays for intracellular cytokine staining, using Wuhan and BA.2 antigens, and chemiluminescence microparticle immunoassay to detect SARS-CoV-2 antibodies. Logistic regression models were applied. A total of 215 (95.6%) participants exhibited T-cell response (TCR) to at least one antigen. Positive responses of CD4+ and CD8+ T cells were 89.8% and 85.3%, respectively. No difference in CIR was found between naïve and infected patients. Patients who experienced sequelae exhibited a higher CIR than those without. A positive correlation was observed between TCR and anti-spike IgG levels. Factors positively associated with the TCR included blood group A, number of SARS-CoV-2 vaccine doses received, and anti-N IgM; factors inversely related were the time elapsed since the last vaccine dose or infection, and blood group B. These findings contribute valuable insights into the nuanced immune landscape shaped by SARS-CoV-2 infection and vaccination.

Long COVID Prevalence and the Impact of the Third SARS-CoV-2 Vaccine Dose: A Cross-Sectional Analysis from the Third Follow-Up of the Borriana Cohort, Valencia, Spain (2020-2022).

BACKGROUND: In March 2020, a COVID-19 outbreak linked to mass gathering dinners at the Falles Festival in Borriana, Spain, resulted in an estimated attack rate of 42.6% among attendees. METHODS: In June 2022, we conducted a cross-sectional follow-up study of 473 adults aged 18 to 64 who attended the dinners at the Falles Festival in 2020, examining the cumulative experience after SARS-CoV-2 infection and vaccination responses. Data included demographic details, lifestyle habits, medical history, infection records, and vaccinations from a population-based vaccine registry. Blood samples were analyzed for SARS-CoV-2 antibodies and cellular immunity. We employed a doubly robust inverse-probability weighting analysis to estimate the booster vaccine dose's impact on long COVID prevalence and symptom count. RESULTS: A total of 28.1% of participants met the WHO criteria for long COVID, with older individuals showing higher rates. Long COVID diagnosis was less likely with factors including O blood group, higher occupational status, physical activity, three vaccine doses, strong SARS-CoV-2-S-reactive IFNγ-producing-CD8+ response, and infection during the Omicron period. Increased age, high or low social activity, underlying health conditions, a severe initial COVID episode, and reinfection were associated with higher long COVID likelihood. A booster dose, compared to one or two doses, reduced long COVID risk by 74% (95% CI: 56% to 92%) and symptom count by 55% (95% CI: 32% to 79%). CONCLUSION: Long COVID was prevalent in a significant portion of those who contracted COVID-19, underscoring the need for sustained follow-up and therapeutic strategies. Vaccinations, notably the booster dose, had a substantial beneficial effect on long-term infection outcomes, affirming the vaccination's role in mitigating SARS-CoV-2 infection consequences.

[Evolution of the incidence and survival of bronchogenic carcinoma in the province of Castellón (Spain) from 2004 to 2017.] / Evolución de la incidencia y supervivencia del carcinoma broncogénico en la provincia de Castellón en el periodo de tiempo 2004-2017.

OBJECTIVE: Bronchogenic carcinoma (BC) is the second most frequent worldwide and the most lethal tumour in both sexes. Its incidence varies not only among countries but also among different areas of the same country. So, the aim of this work was to analyse the evolution of its incidence and survival in the province of Castellón from 2004 to 2017 and to compare them with those of de rest of the country. METHODS: A retrospective observational study was carried out from patients diagnosed with BC and registered in the Castellón Tumour Register from 2004 to 2017. Survival was estimated using the Kaplan-Meier method whereas to estimate the relationship among different variables both the chi-square and ANOVA test were used. RESULTS: 4,346 cases were diagnosed, whose mean age was 67.5±11.3 years, 85.2% men, the most frequent histological types were adenocarcinoma (28.3%) and epidermoid carcinoma (25.1%). The gross global incidence was 53.4 cases/105 inhabitants, 90.9 cases/105 men and 15.7 cases/105 women. Median global survival at five years was 12.7%, 12% in men and 18.4% in women. CONCLUSIONS: The global incidence of BC in Castellón is lower than the national one, having remained stable in men while it is double in women. Global survival at five years is less than 15%, being higher in women than in men, nevertheless it increases compared to that of previous studies.

OBJETIVO: El carcinoma broncogénico (CB) es el segundo tumor más frecuente a nivel mundial y el más letal en ambos sexos. Su incidencia varía, no sólo entre países, sino también entre diferentes zonas de un mismo país. Por tanto, el objetivo de este trabajo fue analizar la evolución de su incidencia y la supervivencia en la provincia de Castellón desde 2004 hasta 2017, y compararlas con las del resto del país. METODOS: Se realizó un estudio observacional retrospectivo en pacientes diagnosticados de CB e inscritos en el Registro de Tumores de Castellón desde 2004 hasta 2017. La supervivencia se estimó mediante el método de Kaplan-Meier, mientras que para estimar la relación entre distintas variables se utilizaron los test Chi-cuadrado y ANOVA. RESULTADOS: Se diagnosticaron 4.346 casos, con una edad media de 67,5±11,3 años, el 85,2% eran hombres, los tipos histológicos más frecuentes fueron adenocarcinoma (28,3%) y carcinoma epidermoide (25,1%). La incidencia global bruta fue de 53,4 casos/105 habitantes, con 90,9 casos/105 de hombres y 15,7 casos/105 de mujeres. La mediana de supervivencia global a los cinco años fue del 12,7%, siendo del 12% en hombres y del 18,4% en mujeres. CONCLUSIONES: La incidencia global de CB en Castellón es inferior a la nacional, habiéndose mantenido estable en hombres mientras que se duplica en mujeres. La supervivencia global a los cinco años es inferior al 15%, siendo mayor en mujeres que en hombres; no obstante, aumenta respecto a la reportada en estudios previos.

Incidence and Risk Factors of the COVID-19 Pandemic: An Epidemiological Approach.

After three years of the COVID-19 pandemic, it is certain that the SARS-CoV-2 virus has been a turning point for humanity in both developed and developing countries [...].

ABO Blood Groups and Incidence of COVID-19 in the Mass Gathering Events in Borriana (Spain), March 2020: A Retrospective Cohort Study.

Our objective was to estimate the incidence of COVID-19 and the ABO blood Groups in the mass-gathering events (MGEs) during the Falles Festival in Borriana (Spain) from 6-10 March 2020. We conducted a population-based retrospective cohort study and measured anti-SARS-CoV-2 antibodies and the ABO of participants. We performed laboratory COVID-19 tests and obtained the ABO in 775 subjects (72.8% of the original exposed cohort): O-group (45.2%), A-group (43.1%), B-group (8.5%) and AB-group (3.4%). Adjusted for confounding factors, including COVID-19 exposure during the MGEs, attack rates of COVID-19 for each ABO group were 55.4%, 59.6%, 60.2%, and 63.7%. The adjusted relative risks were for O-group 0.93 (95% Confidence Interval [CI] 0.83-1.04), for A-group 1.06 (95% CI 0.94-1.18), for B-group 1.04 (95%CI 0.88-1.24), and for AB-group 1.11 (95% CI 0.81-1.51) with no significant differences. Conclusions: Our results suggest no effect of ABO on COVID-19 incidence. We observed weak but not significant protection of the O-group and not a significantly greater infection risk for the remaining groups compared with the O-group. More studies are needed to resolve the controversies regarding the association between ABO and COVID-19.

Incidence, Hospitalization, Mortality and Risk Factors of COVID-19 in Long-Term Care Residential Homes for Patients with Chronic Mental Illness.

Long-term care residential homes (LTCRH) for patients with chronic mental illness have suffered the enormous impact of COVID-19. This study aimed to estimate incidence, hospitalization, mortality, and risk factors of COVID-19 to prevent future epidemics. From March 2020 to January 2021 and before vaccination anti-SARS-CoV-2 begins, cumulate incidence rate (CIR), hospitalization rate (HR), mortality rate (MR), and risk factors of COVID-19 in the 11 LTCRH of two Health Departments of Castellon (Spain) were studied by epidemiological surveillance and an ecological design. Laboratory tests confirmed COVID-19 cases, and multilevel Poisson regression models were employed. All LTCRH participated and comprised 346 residents and 482 staff. Residents had a mean age of 47 years, 40% women, and suffered 75 cases of COVID-19 (CIR = 21.7%), five hospitalizations (HR = 1.4%), and two deaths (MR = 0.6%) with 2.5% fatality-case. Staff suffered 74 cases of the disease (CIR = 15.4%), one hospitalization (HR = 0.2%), and no deaths were reported. Risk factors associated with COVID-19 incidence in residents were private ownership, severe disability, residents be younger, CIR in municipalities where LTCRH was located, CIR in staff, and older age of the facilities. Conclusion: COVID-19 incidence could be prevented by improving infection control in residents and staff and modernizing facilities with increased public ownership.

Incidence, Mortality, and Risk Factors of COVID-19 in Nursing Homes.

During the period from March 2020 to January 2021, we performed an analysis of incidence, mortality, and risk factors of COVID-19 in nursing homes (NHs) in two health departments (HDs) of Castellon (Spain) 2021 through epidemiological surveillance and an ecological design. Laboratory-confirmed COVID-19 cases, cumulative incidence rate (CIR), and mortality rate (MR) of 27 NHs were collected. Information of residents, staff, and facilities was obtained by questionnaire. Multilevel Poisson regression models were applied. All NHs in the HDs participated with 2229 residents (median: 83 years old, 67.3% women) and 1666 staff. Among residents, 815 cases (CIR: 34.8 per 100) and 202 deaths (MR: 8.7 per 100, case fatality 21.0%) were reported and, among staff, 296 cases (CIR: 19.2 per 100) without deaths. Residents' CIR and MR increased with staff CIR, age of the building, residents/staff ratios, occupancy rate, and crowding index; CIR increased with private NH ownership, large NH size, large urban area, and the percentage of women residents; and MR was associated with residents' severe disabilities. In conclusion, several risk factors of COVID-19 incidence and mortality can be prevented by improving infection and quality controls, ameliorating residents/staff ratios, improving structural facilities, and increasing NH public ownership to avoid new outbreaks.

Complications Post-COVID-19 and Risk Factors among Patients after Six Months of a SARS-CoV-2 Infection: A Population-Based Prospective Cohort Study.

In October 2020, we conducted a population-based prospective cohort study to determine post-COVID-19 complications, recovery, return to usual health, and associated risk factors in 536 cases of COVID-19 outbreak in Borriana (Spain) by administering an epidemiological questionnaire via phone interviews. A total of 484 patients participated (90.3%), age mean 37.2 ± 17.1 years, and 301 females (62.2%). Mild illness was the most common COVID-19 manifestation. After six months, 160 patients (33.1%) suffered at least one complication post-COVID-19, and 47 (29.4%) of them sought medical assistance. The most frequent persistent symptoms were hair loss, fatigue, loss of smell or taste, and headache. Risk factors associated with a complication were female sex (adjusted relative risk, [aRR] = 1.93 95% confidence interval [CI] 1.41-2.65), age 35 years and above (aRR = 1.50 95% CI 1.14-1.99), B blood group (aRR = 1.51 95% CI 1.04-2.16), current smoker (RR = 1.61 95% CI 1.02-2.54), and at least a COVID-19 exposure (aRR = 2.13 95% CI 1.11-4.09). Male sex, age younger than 35 years, and low COVID-19 exposures were associated with better recovery and return to usual health. A third of patients presented persistent symptoms compatible with the long-COVID-19 syndrome. In conclusion, an active medical follow-up of post-COVID-19 patients must be implemented.

Maternal Mortality in Africa: Regional Trends (2000-2017).

BACKGROUND: United Nations Sustainable Development Goals state that by 2030, the global maternal mortality rate (MMR) should be lower than 70 per 100,000 live births. MMR is still one of Africa's leading causes of death among women. The leading causes of maternal mortality in Africa are hemorrhage and eclampsia. This research aims to study regional trends in maternal mortality (MM) in Africa. METHODS: We extracted data for maternal mortality rates per 100,000 births from the United Nations Children's Fund (UNICEF) databank from 2000 to 2017, 2017 being the last date available. Joinpoint regression was used to study the trends and estimate the annual percent change (APC). RESULTS: Maternal mortality has decreased in Africa over the study period by an average APC of -3.0% (95% CI -2.9; -3,2%). All regions showed significant downward trends, with the greatest decreases in the South. Only the North African region is close to the United Nations' sustainable development goals for Maternal mortality. The remaining Sub-Saharan African regions are still far from achieving the goals. CONCLUSIONS: Maternal mortality has decreased in Africa, especially in the South African region. The only region close to the United Nations' target is the North African region. The remaining Sub-Saharan African regions are still far from achieving the goals. The West African region needs more extraordinary efforts to achieve the goals of the United Nations. Policies should ensure that all pregnant women have antenatal visits and give birth in a health facility staffed by specialized personnel.

[Post-vaccination antibodies against SARS-CoV-2 in a cohort of workers of a general hospital]. / Anticuerpos postvacunales frente a SARS-CoV-2 en una cohorte de trabajadores de un hospital general.

INTRODUCTION: The aim was to estimate the evolution of the levels of anti-SARS-CoV-2 antibodies, the associated factors, and the incidence of new infections during the follow-up period.  Method: Prospective cohort study of a representative sample of workers at the General University Hospital of Castellon 8 months after receiving the second dose of Pfizer-BioNTech vaccine against SARS-CoV-2, by determining IgG-S, IgG-NP, follow-up and response to a questionnaire. The results were compared with those at the start of the cohort in February 2021. Multivariate linear regression and Poisson regression were used.  Results: A total of 253 workers participated out of the 275 in the start of the cohort. All had detectable levels of IgG-S, median 691% AU/ml, decreasing by 93.3% compared with the first study. The decline of IgG-S increased with age and obesity; and decreased with a COVID-19 previous history, regular exercise, and in smokers. IgG-NP was positively associated with a history of COVID-19, taking vitamin D, and decreased from 4.4% to 1.2%. There were 4 new cases of COVID-19 in the cohort, with and incidence rate of 1.7%. One death occurred in a participant with immunosuppressive treatment, only one case was asymptomatic and no reinfections occurred. CONCLUSIONS: A general decrease of IgG-S and IgG-NP antibodies after the second dose of Pfizer-BioNTech vaccine was observed in the cohort, as well as with new SARS-CoV-2 infections. Booster doses, maintaining protective measures and further determination of the protection threshold of vaccination are recommended.

Introducción: Estimar la evolución de los niveles de anticuerpos anti-SARS-CoV-2 y los factores asociados, así como la incidencia de nuevas infecciones. Método: Estudio de cohorte prospectivo de una muestra representativa de trabajadores del Hospital General Universitario de Castellón a los 8 meses de recibir la 2ª dosis de la vacuna Pfizer-BioNTech contra el SARS-CoV-2, mediante la determinación de anticuerpos IgG-S y IgG-NP, y la cumplimentación de un cuestionario. Se compararon los resultados con los del inicio de la cohorte en febrero de 2021. Se usó regresión lineal múltiple y regresión de Poisson.  Resultados: Participaron 253 trabajadores de los 275 reclutados al inicio de la cohorte (92%). Todos mantenían niveles detectables de IgG-S, mediana de 691,5 UA/ml, disminuyendo un 93,3% con respecto al inicio. Los descensos de IgG-S fueron mayores con la edad y la obesidad, y menores en aquellos con historia de COVID-19, IgG-S elevada inicial, practicar ejercicio habitual y ser fumador. Tener IgG-NP se asoció positivamente con historia de COVID-19, tomar vitamina D, y disminuyeron del 4,4% al 1,2%. Se produjeron 4 casos de COVID-19 en la cohorte, con una tasa de incidencia del 1,7%, con un fallecimiento en un participante con tratamiento inmunosupresor, solo un caso fue asintomático y no hubo reinfecciones.  Conclusiones: Se produce un descenso general de los anticuerpos IgG-S e IgG-NP después de la segunda dosis de vacuna Pfizer-BioNTech, así como nuevas infecciones por SARS-CoV-2. Se recomienda dosis de recuerdo, mantener medidas protectoras y determinar el umbral de anticuerpos protectores de la vacunación.

[Comparison of postvaccinal antibodies to SARS-CoV-2 in asymptomatic cases, symptomatic cases, and non-cases in a cohort of general hospital workers]. / Comparación de anticuerpos postvacunales al SARS-CoV-2 en casos asintomáticos, casos sintomáticos, y no casos de una cohorte de trabajadores de un hospital general.

Estimada Sra. Directora: Agradecemos a los doctores Rujittika Mungmunpuntipantip y Viroj Wiwanitkit su interés por nuestra publicación(1) en la carta en la que se subrayan la importancia de los casos asintomáticos de COVID-19 en la evaluación de los efectos de la vacunación anti-SARS-CoV-2(2). Compartimos con ellos que las personas asintomáticas al COVID-19 pueden presentar unos niveles de anticuerpos anti-SARS-CoV-2 IgG-S mayores que las personas sin historia previa de COVID-19, y que pueden diferir en las reacciones a la vacunación, considerando que la prevalencia de COVID-19 asintomáticos se ha descrito como elevada(3).  En nuestra cohorte de trabajadores del Hospital General Universitario de Castellón, se detectaron 5 casos de COVID-19 asintomáticos (CA), incluyendo los dos seguimientos realizados(1,4), y 20 casos presentaron síntomas de COVID-19 (CS), con un total de 25 casos con confirmación por el laboratorio, 20 % tasa de asintomáticos (5/25). En la tabla 1 se recogen las características de los CA, CS, y de los participantes que no habían sufrido la enfermedad. Los CA eran más jóvenes que los otros 2 grupos, y la proporción de varones era significativamente mayor (p=0,027). En cuanto a los anticuerpos Anti-SARS-CoV-2 IgG-S al mes de la vacunación, los niveles de los CS fueron mayores que los de CA, y de los no casos, siendo estos últimos los que tuvieron significativamente menores niveles (p<0,001). Sin embargo, a los 8 meses de la vacunación la caída de IgG-S fue general, y los niveles de IgG-S eran mayores en los CA que en los CS y en los no casos (p<0,001). Los niveles de IgG-S considerados como protectores ? 4160 UA/ml, eran mayores en los CA y CS que el de los no casos (p=0,001). Si bien, el declive era similar en los tres grupos (p=0,084). Los síntomas y los efectos secundarios de las dos dosis de vacuna Pfizer-BioNTech no presentaron diferencias significativas entre los grupos. Estos resultados son coincidentes con númerosos estudios, en los que se constata que los casos de COVID-19 presentan niveles más elevados de IgG-S que las personas que no han sufrido la enfermedad(5), y se apreció que en valores medio no se alcanzaron los niveles de IgG-S protectores. De aquí la importancia de disponer de marcadores más efectivos de la situación de protección de la personas vacunadas tanto si han sufrido la enfermedad como sino. Además de los anticuerpos neutralizantes, la determinación de la inmunidad celular podría ser muy conveniente para conocer los niveles de protección.

[Vaccine response to SARS-CoV-2 in hospital workers]. / Respuesta vacunal frente a SARS-CoV-2 en trabajadores de un hospital.

INTRODUCTION: The aim of this study was to measure anti-SARS-CoV-2 immunity of hospital workers after a completed 2-dose Pfizer-BionTech vaccination, and to examine factors potentially associated with immunity status. Side effects of the vaccine were also studied. METHOD: This was a cross-sectional study of a representative sample of General University Hospital of Castellon workers, vaccinated with two doses in January and February 2021. We measured IgG antibodies against protein N (IgG-NP), IgM against protein S (IgM-S), and quantitative levles of IgG against protein S (IgG-Quant) one month after the last dose. We obtained information on demographic, risk factors, and vaccine side effects via a self-completed questionnaire. For the statistical analysis we used multiple regression models. RESULTS: Two hundred seventy-five workers participated (96.8%, 275/284). Positive IgG-Quant, IgM-S, and IgG-NP were 99.6%, 14.9% and 4.4%, respectively. Adjusted IgG-Quant levels increased significantly with obesity, nonsmoking status, positive IgM-S, and/or IgG-NP. The prevalence of IgM-S was higher in males, and associated with the same factors as those for IgG-Quant. Among those with a history of COVD-19 infection, 42.9% did not have IgG-NP. Overall 86.5% of participants had side effects, which were associated with positive IgG-NP, high IgG-Quant levels, younger age, and being female. CONCLUSIONS: All but one participant developed immunity. Those who had suffered from COVID-19 infection had higher antibody levels. A high proportion of participants had mild secondary effects, especially those with previous COVID-19 infection.

Introducción: Evaluar la inmunidad de los trabajadores de un hospital tras haber completado la vacunación Pfizer-BionTech, y su relación con factores individuales. También describir los efectos adversos de la vacuna. Método: Estudio transversal de una muestra de los trabajadores del Hospital General Universitario de Castellón vacunados con dos dosis en enero y febrero de 2021. Un mes después se detectaron: anticuerpos IgG frente a la proteína N (IgG-NP), de IgM frente a la proteína S (IgM-S) y detección cuantitativa de IgG frente a la proteína S (IgG-Quant). Se utilizó un cuestionario para recoger datos demográficos, factores de riesgo y efectos secundarios. En el análisis estadístico se utilizaron modelos de regresión múltiple. Resultados: La participación fue del 96,8% (275/284). Presentaron IgG-Quant el 99,6%, 14,9% IgM-S, y 4,4% IgG-NP. El nivel ajustado de IgG-Quant aumentó significativamente con la obesidad, en no fumadores y con positividad IgM-S y/o IgG-NP. La prevalencia de IgM-S era mayor en varones, y se asociaba con los mismos factores que la IgG-Quant. De los infectados por COVID-19, el 42,9% no presentaron IgG-NP. Un 86,5% sufrió algún efecto secundario que se asoció a tener IgG-NP, mayores niveles de IgG-Quant, y fue más frecuente en jóvenes y mujeres. Conclusiones: Todos los participantes desarrollaron inmunidad humoral excepto uno. Tuvieron mayores niveles de anticuerpos los que habían padecido la COVID-19. Un porcentaje alto desarrolló efectos secundarios leves, más frecuentes en los que habían padecido la enfermedad.

ABO Blood Groups and the Incidence of Complications in COVID-19 Patients: A Population-Based Prospective Cohort Study.

After a COVID-19 outbreak in the Falles festival of Borriana (Spain) during March 2020, a cohort of patients were followed until October 2020 to estimate complications post-COVID-19, considering ABO blood groups (ABO). From 536 laboratory-confirmed cases, 483 completed the study (90.1%) carried by the Public Health Center of Castelló and the Emergency and Microbiology and Clinical Analysis of Hospital de la Plana Vila-real. The study included ABO determination and telephone interviews of patients. The participants had a mean age of 37.2 ± 17.1 years, 300 females (62.1%). ABO were O (41.4%), A (45.5%), B (9.1%), and AB (3.9%). We found no difference in the incidence of COVID-19 infections. A total of 159 (32.9%) patients reported one or more post-COVID-19 complications with divergent incidences after adjustment: O (32.3%), A (32.6%), B (54.1%), and AB (27.6%); B groups had more complications post-COVID-19 when compared with O group (adjusted relative risk [aRR] 95% confidence interval [CI] 1.68, 95% CI 1.24-2.27), and symptoms of fatigue (1.79, 95% CI 1.08-2.95), myalgia (2.06, 95% CI 1.10-3.84), headache (2.61, 95% CI 1.58-4.31), and disorder of vision (4.26 95% CI 1.33-13.60). In conclusion, we observed significant differences in post-COVID-19 complications by ABO, with a higher incidence in B group. Additional research is justified to confirm our results.

"Mass gathering events and COVID-19 transmission in Borriana (Spain): A retrospective cohort study".

OBJECTIVE: Mass gathering events (MGEs) are associated with the transmission of COVID-19. Between 6 and 10 March 2020, several MGEs related to the Falles festival took place in Borriana, a municipality in the province of Castellon (Spain). The aim of this study was to estimate the incidence of COVID-19 and its association with these MGEs, and to quantify the potential risk factors of its occurrence. METHODS: During May and June 2020, a population-based retrospective cohort study was carried out by the Public Health Center of Castelló and the Hospital de la Plana in Vila-real. Participants were obtained from a representative sample of 1663 people with potential exposure at six MGEs. A questionnaire survey was carried out to obtain information about attendance at MGEs and COVID-19 disease. In addition, a serologic survey of antibodies against SARS-Cov-2 was implemented. Inverse probability weighted regression was used in the statistical analysis. RESULTS: A total of 1338 subjects participated in the questionnaire survey (80.5%), 997 of whom undertook the serologic survey. Five hundred and seventy cases were observed with an attack rate (AR) of 42.6%; average age was 36 years, 62.3% were female, 536 cases were confirmed by laboratory tests, and 514 cases were found with SARS-CoV-2 total antibodies. Considering MGE exposure, AR was 39.2% (496/1264). A dose-response relationship was found between MGE attendance and the disease, (adjusted relative risk [aRR] = 4.11 95% confidence interval [CI]3.25-5.19). Two MGEs with a dinner and dance in the same building had higher risks. Associated risk factors with the incidence were older age, obesity, and upper and middle class versus lower class; current smoking was protective. CONCLUSIONS: The study suggests the significance of MGEs in the COVID-19 transmission that could explain the subsequent outbreak in Borriana.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Setting-specific Transmission Rates: A Systematic Review and Meta-analysis.

BACKGROUND: Understanding the drivers of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission is crucial for control policies, but evidence of transmission rates in different settings remains limited. METHODS: We conducted a systematic review to estimate secondary attack rates (SARs) and observed reproduction numbers (Robs) in different settings exploring differences by age, symptom status, and duration of exposure. To account for additional study heterogeneity, we employed a beta-binomial model to pool SARs across studies and a negative-binomial model to estimate Robs. RESULTS: Households showed the highest transmission rates, with a pooled SAR of 21.1% (95% confidence interval [CI]:17.4-24.8). SARs were significantly higher where the duration of household exposure exceeded 5 days compared with exposure of ≤5 days. SARs related to contacts at social events with family and friends were higher than those for low-risk casual contacts (5.9% vs 1.2%). Estimates of SARs and Robs for asymptomatic index cases were approximately one-seventh, and for presymptomatic two-thirds of those for symptomatic index cases. We found some evidence for reduced transmission potential both from and to individuals younger than 20 years of age in the household context, which is more limited when examining all settings. CONCLUSIONS: Our results suggest that exposure in settings with familiar contacts increases SARS-CoV-2 transmission potential. Additionally, the differences observed in transmissibility by index case symptom status and duration of exposure have important implications for control strategies, such as contact tracing, testing, and rapid isolation of cases. There were limited data to explore transmission patterns in workplaces, schools, and care homes, highlighting the need for further research in such settings.

Production of Vegetables and Artichokes Is Associated with Lower Cardiovascular Mortality: An Ecological Study.

Mortality due to cardiovascular disease (CVD), including cerebrovascular disease (CED) and ischaemic heart disease (IHD), was considerably different in eight municipalities of the province of Castellón, Community of Valencia (Spain) during the period of 1991-2011. In addition, these villages showed differences in agricultural practices and production. Since high vegetable consumption has been linked to decreased all-cause, CVD, and CED mortalities, we hypothesized that the diversity in vegetable and artichoke production, used as proxies for their consumption, could be associated with the diversity of mortality rates. In order to test our hypothesis, we estimated the smoothed standardized mortality ratios (SMRs) of CVD, CED, and IHD mortalities and a directed, age-adjusted mortality rate (AMR). We used a multilevel linear regression analysis to account for the ecological nature of our study. After adjustment, the CVD and CED SMRs were inversely associated with vegetable and artichoke production, with a reduction in SMRs for CVD: -0.19 (95% Confidence Interval [CI] -0.31 to -0.07) and -0.42 (95% CI -0.70 to -0.15) per hectare/103 inhabitants, respectively. The SMRs for CED also decreased: -0.68 (95% CI -1.61 to -0.19) and -1.47 (95% CI -2.57 to -0.36) per hectare/103 inhabitants, respectively. The SMRs for IHD were not associated with vegetal and artichoke production. When the directed AMR was used, CED mortality was consistent with the previous results, whereas the CVD mortality association was lost. Our results indicate that vegetable and artichoke production may act as protective factors of CED and CVD mortalities.

Vitamin D status and risk of incident tuberculosis disease: A nested case-control study, systematic review, and individual-participant data meta-analysis.

BACKGROUND: Few studies have evaluated the association between preexisting vitamin D deficiency and incident tuberculosis (TB). We assessed the impact of baseline vitamins D levels on TB disease risk. METHODS AND FINDINGS: We assessed the association between baseline vitamin D and incident TB in a prospective cohort of 6,751 HIV-negative household contacts of TB patients enrolled between September 1, 2009, and August 29, 2012, in Lima, Peru. We screened for TB disease at 2, 6, and 12 months after enrollment. We defined cases as household contacts who developed TB disease at least 15 days after enrollment of the index patient. For each case, we randomly selected four controls from among contacts who did not develop TB disease, matching on gender and year of age. We also conducted a one-stage individual-participant data (IPD) meta-analysis searching PubMed and Embase to identify prospective studies of vitamin D and TB disease until June 8, 2019. We included studies that assessed vitamin D before TB diagnosis. In the primary analysis, we defined vitamin D deficiency as 25-(OH)D < 50 nmol/L, insufficiency as 50-75 nmol/L, and sufficiency as >75nmol/L. We estimated the association between baseline vitamin D status and incident TB using conditional logistic regression in the Lima cohort and generalized linear mixed models in the meta-analysis. We further defined severe vitamin D deficiency as 25-(OH)D < 25 nmol/L and performed stratified analyses by HIV status in the IPD meta-analysis. In the Lima cohort, we analyzed 180 cases and 709 matched controls. The adjusted odds ratio (aOR) for TB risk among participants with baseline vitamin D deficiency compared to sufficient vitamin D was 1.63 (95% CI 0.75-3.52; p = 0.22). We included seven published studies in the meta-analysis and analyzed 3,544 participants. In the pooled analysis, the aOR was 1.48 (95% CI 1.04-2.10; p = 0.03). The aOR for severe vitamin D deficiency was 2.05 (95% CI 0.87-4.87; p trend for decreasing 25-(OH)D levels from sufficient vitamin D to severe deficiency = 0.02). Among 1,576 HIV-positive patients, vitamin D deficiency conferred a 2-fold (aOR 2.18, 95% CI 1.22-3.90; p = 0.01) increased risk of TB, and the aOR for severe vitamin D deficiency compared to sufficient vitamin D was 4.28 (95% CI 0.85-21.45; p = 0.08). Our Lima cohort study is limited by the short duration of follow-up, and the IPD meta-analysis is limited by the number of possible confounding covariates available across all studies. CONCLUSION: Our findings suggest vitamin D predicts TB disease risk in a dose-dependent manner and that the risk of TB disease is highest among HIV-positive individuals with severe vitamin D deficiency. Randomized control trials are needed to evaluate the possible role of vitamin D supplementation on reducing TB disease risk.

Pulmonary Versus Extrapulmonary Tuberculosis Associated Factors: A Case-Case Study.

BACKGROUND: Tuberculosis (TB) incidence remains low in health departments of Castellon and La Plana-Vila-real, but TB elimination is challenging. The objective of this study was to estimate associated factors of pulmonary tuberculosis (PTB) compared with extrapulmonary tuberculosis (ETB) and investigate epidemiological characteristics of these pathologies to orient control and prevention actions. MATERIALS AND METHODS: A prospective case-case study was implemented by comparing PTB and ETB incidences during 2013-2016 from notification reports, epidemiological surveillance, and microbiological results of hospitals' laboratories Hospital General Castellon and La Plana-Vila-Real in the province of Castellon of Valencia region in Spain. In this design, cases were patients with PTB and controls were patients with ETB. Directed acyclic graph approach was used for selection of potential risk and confounding factors. Adjusted odds ratios (AORs) were estimated by logistic regression models. RESULTS: The study included 136 patients with PTB and 57 patients with ETB, with microbiological confirmation of 93.4% and 52.6%, and the annual median of incidence rates were 7.5 and 3.1 per 100 000 inhabitants, respectively. In general, patients with PTB were younger with higher male proportion than patients with ETB. Risk factors of PTB were smoking tobacco (AOR = 3.98; 95% confidence interval [CI] = 1.66-9.56), social problems (social marginalization, homeless, residence in shelters for the poor, or stay in prison) (AOR = 3.39; 95% CI = 1.05-10.94), and contact with patients with TB (AOR = 2.51; 95% CI = 1.06-5.95). No-smoking tobacco and no-drug abuse interaction decrease PTB risk (AOR = 0.27; 95% CI = 0.12-0.64). From these results, specific measures of health promotion and prevention can be addressed. CONCLUSIONS: The estimated associated factors of PTB may be prevented, and it was demonstrated that the case-case design is useful in the study of TB.