[Brote de la COVID-19 en una residencia en ancianos correctamente vacunados. Influencia de la inmunidad híbrida en la carga viral, el riesgo de infección y el riesgo de progresión de la enfermedad]. / COVID-19 outbreak in a properly vaccinated nursing home. Influence of hybrid immunity on viral load, risk of infection and risk of disease progression.

OBJECTIVE: This study addressed a COVID-19 outbreak in a nursing home, where the residents were vaccinated with two doses of Comirnaty® and thirty of them had previously had the infection. Outbreaks in closed communities are opportunities to study the entire clinical spectrum of the disease and, as in this case, the effect of hybrid immunity on transmission, infection progression and viral load. METHODS: A descriptive and retrospective cohort study in the resident population was carried out. Attack rates were calculated for one of four stages of the disease: infection, symptomatic infection, hospitalization, and death. Relative risks (RR) were then estimated using simple and multivariate Poisson regression for each of these stages. RESULTS: The attack rate was 59% (56/95). The clinical spectrum was the same in both sexes. There was a notable protective effect of hybrid immunity against transmission (67%). In terms of progression, those with hybrid immunity had a lower risk of symptomatic infection. Nasopharyngeal viral load was significantly lower in individuals with hybrid immunity and asymptomatic individuals, supporting the idea of lower transmissibility in this group. Age was identified as a risk factor for disease progression. Molecular analysis identified the Delta B.1.617.2 variant in the patients and an air sample, supporting aerosol transmission in closed, poorly ventilated environments. CONCLUSIONS: This study provides a comprehensive view of an outbreak in a vaccinated nursing home, highlighting the importance of hybrid immunity. The results support the individual consideration of previous infection history when assessing the risk of COVID-19, contributing to the understanding of the evolution of the pandemic in the future.

OBJECTIVE: Este estudio abordó un brote de la COVID-19 en una residencia de ancianos, donde los residentes estaban vacunados con dos dosis de Comirnaty® y treinta de ellos habían pasado anteriormente la infección. Los brotes en colectivos cerrados son oportunidades para estudiar todo el espectro clínico de la enfermedad y, como en este caso, el efecto de la inmunidad híbrida sobre la transmisión, la progresión de la infección y la carga viral. METHODS: Se realizó un estudio descriptivo y de cohortes retrospectivo en la población de residentes. Se calcularon las tasas de ataque para uno de cuatro estadios de la enfermedad: infección, infección sintomática, hospitalización y defunción. Después se estimaron los riesgos relativos (RR) mediante regresión de Poisson simple y multivariante para cada uno de esos estadios. RESULTS: La tasa de ataque fue del 59% (56/95). El espectro clínico fue igual en ambos sexos. Hubo un notable efecto protector de la inmunidad híbrida contra la transmisión (67%). En términos de progresión, aquellos con inmunidad híbrida presentaron un riesgo menor de infección sintomática. La carga viral nasofaríngea fue significativamente menor en individuos con inmunidad híbrida y asintomáticos, respaldando la idea de una menor transmisibilidad en este grupo. La edad se identificó como un factor de riesgo para la progresión de la enfermedad. El análisis molecular identificó la variante Delta B.1.617.2 en los pacientes y una muestra de aire, lo que respaldó la transmisión por aerosol en entornos cerrados y mal ventilados. CONCLUSIONS: Este estudio proporciona una visión integral de un brote en una residencia de ancianos vacunados, destacando la importancia de la inmunidad híbrida. Los resultados respaldan la consideración individual de la historia de infección previa al evaluar el riesgo de la COVID-19, contribuyendo a la comprensión de la evolución de la pandemia en el futuro.

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.

[Impact of the pandemic on various infectious diseases with different epidemiological patterns of seasonality, transmission and age]. / Impacto de la pandemia en varias enfermedades infecciosas con patrones epidemiológicos distintos de estacionalidad, transmisión y edad.

OBJECTIVE: The COVID-19 pandemic has had a strong impact on other infectious diseases. The aim of this paper was to analyze the epidemiological changes that occurred during the pandemic in eight infectious diseases with different epidemiological patterns: influenza, respiratory syncytial virus, rotavirus, pneumococcus, Campylobacter, non-typhoid Salmonella, gonorrhea and herpes zoster. METHODS: From the Microbiological Surveillance Network, the time series of cases was traced from January 2017 to March 2023. Three periods were distinguished: reference, pandemic and beginning of the post-pandemic. The distribution by age and sex in these periods was analyzed. Incidence rates and rate ratios (RR) were calculated. These RRs and their 95% confidence intervals were estimated overall and by year of age in children under five years of age. RESULTS: Statistically significant differences were found in the impact that the pandemic had on each of these diseases. Some, after a period of epidemic silence, have revealed an intense post-pandemic rebound. The post-pandemic global RT increased for influenza (2.4), RSV (1.9) and gonorrhea (3.1); rotavirus recovered its pre-pandemic level (1.07); and pneumococcus (0.84), Campylobacter (0.83) and Salmonella (0.60) decreased. In children under 5 years of age, the patterns were specific and heterogeneous for each disease. CONCLUSIONS: The impact of the pandemic is very different in these diseases. Pediatric and respiratory-transmitted seasonal viral infections are the ones that are most affected, but with different patterns of recovery to normality. Gastrointestinal bacterial infections suffer fewer variations, except for rotavirus. Gonorrhea do not interrupt its increasing trend seen in the pre-pandemic. Shingles show a slight post-pandemic increase. Several diseases with different epidemiological patterns have been studied for a sufficient period to observe how the acute phase of the pandemic emerges.

OBJECTIVE: La pandemia de la COVID-19 ha tenido un fuerte impacto sobre otras enfermedades infecciosas. El objetivo de este trabajo fue analizar los cambios epidemiológicos acaecidos durante la pandemia en ocho enfermedades infecciosas con patrones epidemiológicos distintos: la gripe; virus respiratorio sincitial; rotavirus; neumococo; Campylobacter; Salmonella no tifoidea; gonococia; herpes zóster. METHODS: A partir de la Red de Vigilancia Microbiológica, se trazó la serie temporal de casos desde enero de 2017 a marzo de 2023. Se distinguieron tres periodos: prepandemia (referencia), pandemia e inicio de la pospandemia. Se analizó la distribución por edad y sexo en esos periodos. Se calcularon las tasas de incidencia y las razones de tasas (RT). Se estimaron esas RT globales y sus intervalos de confianza al 95% por cada año de edad en menores de cinco años. RESULTS: Se encontraron diferencias estadísticamente significativas en el impacto que la pandemia tuvo en cada una de esas enfermedades. Algunas, tras un periodo de silencio epidémico, revelaron un repunte intenso pospandémico. Incrementaron la RT global postpandémica la gripe (2,4), VRS (1,9) y gonococia (3,1); recuperó su nivel prepandémico el rotavirus (1,07); y disminuyeron el neumococo (0,84), Campylobacter (0,83) y Salmonella (0,60). En menores de cinco años, los patrones fueron específicos y heterogéneos para cada enfermedad. CONCLUSIONS: El impacto de la pandemia es muy diferente en estas enfermedades. Las infecciones víricas estacionales pediátricas y de transmisión respiratoria son las que más se ven afectadas, pero con patrones de recuperación de la normalidad distintos. Las infecciones bacterianas gastrointestinales sufren menos variaciones, salvo el rotavirus. La gonococia no interrumpe su tendencia al aumento avistada ya en la prepandemia. El herpes zóster muestra un ligero incremento pospandémico. Se han estudiado varias enfermedades con distinto patrón epidemiológico durante un periodo suficiente para observar cómo se produce la salida de la fase aguda de la pandemia.

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.

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.

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.

Missing Cases of Herpes Simplex Virus (HSV) Infection of the Central Nervous System When the Reller Criteria Are Applied for HSV PCR Testing: a Multicenter Study.

Previous studies suggested that herpes simplex virus (HSV) PCR testing can be safely deferred in patients with normal cerebrospinal fluid (CSF) white blood cell (WBC) counts and protein levels as long as they are older than 2 years of age and are not immunocompromised, the so-called Reller criteria. In this multicenter study, we retrospectively assessed the validity of these screening criteria in our setting. A total of 4,404 CSF specimens submitted for HSV PCR testing to the respective microbiology laboratories at the participating hospitals between 2012 and 2018 were included. Six commercially available HSV PCR assays were used across the participating centers. Ninety-one of the 4,404 CSF specimens (2.1%) tested were positive for HSV DNA (75 samples for HSV-1 and 16 for HSV-2). Nine patients failed to meet the Reller criteria, of whom seven were deemed to truly have HSV encephalitis. Overall, no significant correlation between HSV PCR cycle threshold (CT ) values and WBC counts or total protein levels was found. In addition, median HSV PCR CT s were comparable between patients who met the Reller criteria and those who did not (P = 0.531). In summary, we show that HSV DNA may be detected in CSF specimens with normal WBC and protein levels collected from immunocompetent individuals older than 2 years with HSV encephalitis. Nevertheless, the data also indicate that the number of cases detected could be lowered at least by half if CSF specimens with borderline WBC counts (4 cells/mm3) as well as children of any age are systematically tested.

An outbreak of monophasic and biphasic Salmonella Typhimurium, and Salmonella Derby associated with the consumption of dried pork sausage in Castellon (Spain).

An outbreak of S.Typhimurium occurred in several towns and cities in the province of Castellon (Spain) between 23 February and 27 May 2011. On April 5, the microbiology laboratory of a hospital in Castellon alerted the health authorities to the increase in S.Typhimurium isolated in fecal culture of children with gastroenteritis. The serotype and phage-type of 83 positive cases of S.Typhimurium isolated in these period included 49 monophasic/biphasic S.Typhimurium phage type 138, phage type 193, S.Derby, and 34 other S.Typhimurium phage-types. The median of age of patients was 4 years with a range of 0.6-80 years, and the 18% of patients were hospitalised. Two incident matched case-control studies were carried out; the first with S.Typhimurium phage type 138, 193, and S.Derby cases and the second with the other cases. The two studies found that the consumption of brand X dried pork sausage, purchased in a supermarket chain A, was associated with the disease (matched Odds Ratio [mOR]=13.74 95% Confidence Interval [CI] 4.84-39.06 and mOR=8.20 95% CI 2.32-28.89), respectively). S.Typhimurium phage type 193 and S.Derby were isolated in the food taken from the household of two patients and from the supermarket chain's A central warehouse. The pulsed-field gel electrophoresis study confirmed the similarity of the strains from the patients and the food. On May 25 2011, a national food alert led to the withdrawal of the food from the chain A and the outbreak ended.

Outbreak of multidrug-resistant tuberculosis in two secondary schools.

OBJECTIVES: To describe an outbreak of multidrug-resistant tuberculosis (MDR-TB) in two schools METHODS: This was a prospective, observational study of an outbreak of MDR-TB in 2 schools located in the towns of Onda and Nules, in the Spanish province of Castellon, from the moment of detection in November 2008 until November 2014, including patient follow-up and contact tracing. RESULTS: Five cases of MDR-TB were diagnosed. Overall attack rate was 0.9%, and among the contacts traced, 66 had latent tuberculous infection, with an infection rate of 14.4%. Molecular characterization of the 5M. tuberculosis isolates was performed by restriction fragment length polymorphism (RFLP) analysis of the IS6110 sequence. In all 5 patients, cultures were negative at 4-month follow-up, showing the efficacy of the treatment given. No recurrence has been reported to date. CONCLUSIONS: In the context of globalization and the increased prevalence of MDR-TB, outbreaks such as the one presented here are only to be expected. Contact tracing, strict follow-up of confirmed cases, the availability of fast diagnostic techniques to avoid treatment delay, and chemoprophylaxis, together with the molecular characterization of strains, are still essential.

[Trichosporon asahii fatal infection in a preterm newborn]. / Infección fatal por Trichosporon asahii en una recién nacida de pretérmino.

We present a case of Trichosporon asahii fatal infection recognized post mortem in a premature newborn baby of 685 g. Trichosporon asahii isolated from endovascular catheters and endotraqueal tube, is an opportunistic yeast described like an emergent pathogen in serious systemic infections and nosocomial infections in the neonatal intensive care units. The colonization and disease by this uncommon microorganism, usually is unspecific and has similar clinical presentation to other fungal infections with a bad prognosis.

Infección fatal por Trichosporon asahii en una recién nacida de pretérmino / Trichosporon asahii fatal infection in a preterm newborn

Se presenta un caso fatal de infección por Trichos-poron asahii diagnosticado post mortem en una neonato de pretérmino que pesó 685 grs al nacer. De los cultivos de catéteres y del tubo endotraqueal se aisló T. asahii, levadura oportunista descrita como un patógeno emergente en infecciones sistémicas graves e infecciones nosocomiales en las unidades de cuidados intensivos neonatales. La colonización y enfermedad por este microorganismo poco común suele ser inespecífica y con mal pronóstico, de presentación clínica similar a otras infecciones fúngicas.

We present a case of Trichosporon asahii fatal infection recognized post mortem in a premature newborn baby of 685 g. Trichosporon asahii isolated from endovascular catheters and endotraqueal tube, is an opportunistic yeast described like an emergent pathogen in serious systemic infections and nosocomial infections in the neonatal intensive care units. The colonization and disease by this uncommon microorganism, usually is unspecific and has similar clinical presentation to other fungal infections with a bad prognosis.