[Assessing Convalescent Plasma Efficacy in Moderate COVID-19 Hospitalizations: A Bicentric Retrospective Study]. / Uso de plasma de convalecientes de COVID-19 en pacientes hospitalizados por SARS-CoV-2 de moderada grave-dad en la Región de Los Ríos, Chile.

INTRODUCTION: COVID-19 claimed millions of lives, mainly in the pre-vaccine era. Preliminary studies showed promising efficacy of convalescent plasma against SARS-CoV-2 (CP). OBJECTIVE: To evaluate the efficacy of CP in patients hospitalized for COVID-19 with moderate severity. METHODS: Retrospective, bicentric study including adults hospitalized for moderate (non-critical) COVID-19 who required oxygen therapy. CP donated by survivors of mild cases (600 cc) were searched for IgG anti-SARS-CoV-2. Its impact on mortality, hospital stay (days), and need for mechanical ventilation (IMV) was evaluated. RESULTS: Of the 119 patients included, 58% were men (median age 60 years), 88% had comorbidity, and 43% had a high-risk CALL score. Forty-three patients (36%) received CP, only 15 (12.6%) early (< 7 days). Twenty-two patients had to be transferred to the intensive care unit; 18 received IMV, and 15 died (12.6%). The use of CP was not associated with changes in mortality (p = 0.16), need for IMV (p = 0.79), or hospital stay (p = 0.24). Its early administration (< 7 days of symptoms) did not show a significant association either. The presence of heart disease and subsequently requiring IMV were independent factors of mortality. CONCLUSIONS: The use of CP in patients hospitalized for moderately severe COVID-19 was not associated with lower mortality, hospital stay, or the need for IMV.

IgG4-related chronic sclerosing sialadenitis in a child with recurrent parotitis: a case report.

BACKGROUND: IgG4-related disease (IgG4-RD) includes a group of immune-mediated diseases histologically characterized by lymphoplasmacytic infiltrate with a prevalence of IgG4-positive plasma cells, storiform fibrosis and obliterative phlebitis. Autoimmune pancreatitis, sialadenitis, dacryoadenitis and retroperitoneal fibrosis are the most frequent manifestations. IgG4-related sialadenitis usually affects submandibular glands and is very rare in children. Here we report the case of IgG4-related sialadenitis in a six-year-old patient previously diagnosed as juvenile recurrent parotitis. CASE PRESENTATION: A six-year-old patient was referred to our Centre for left parotid swelling of 4 × 3 cm, that was tender, soft in consistency, with overlying red and warm skin. His general condition was good but he was subfebrile; general examination revealed mild enlargement of left cervical lymph nodes. In the last 2 years he had had five episodes of parotitis, diagnosed by another pediatric Center as juvenile recurrent parotitis. On ultrasound examination the left parotid gland appeared enlarged, inhomogeneous, with a colliquative intraparotid lymph node and no evidence of sialolithiasis. Laboratory tests showed an increase of white blood cells and anti-VCA IgM and IgG positivity, with anti-EBNA e anti-EA I negativity. The patient was initially treated with oral antibiotics, but after 10 days the parotid became fluctuating, requiring surgical biopsy and drainage. Postoperative course was regular, with complete remission under oral antibiotic and steroid therapy. Microbiological tests, including cultures for aerobic and anaerobic bacteria, mycobacteria and Bartonella, were negative. Surprisingly, histology showed marked fibrosis and histiocytic and lymphoplasmacellular infiltrate with polyclonal plasma cells mostly expressing IgG4 immunoglobulins. Thus, the diagnosis of IgG4 related chronic sialadenitis in recurrent parotitis and recent EBV infection was made. CONCLUSIONS: IgG4-related sialadenitis is very unusual in children. Histology plays a key role in diagnosis, considering that up to 30% of patients have normal serum IgG4 levels, as shown in our case. The lack of previous histological data makes it impossible to attribute our patient's previous episodes of parotitis to IgG4-RD, though it is a very consistent possibility.

Antimicrobial lock solutions for preventing catheter-related infections in haemodialysis.

BACKGROUND: Patients undergoing haemodialysis (HD) through a central venous catheter (CVC) are exposed to several risks, being a catheter-related infection (CRI) and a CVC lumen thrombosis among the most serious. Standard of care regarding CVCs includes their sealing with heparin lock solutions to prevent catheter lumen thrombosis. Other lock solutions to prevent CRI, such as antimicrobial lock solutions, have proven useful with antibiotics solutions, but not as yet for non-antibiotic antimicrobial solutions. Furthermore, it is uncertain if these solutions have a negative effect on thrombosis incidence. OBJECTIVES: To assess the efficacy and safety of antimicrobial (antibiotic, non-antibiotic, or both) catheter lock solutions for preventing CRI in participants undergoing HD with a CVC. SEARCH METHODS: We searched the Cochrane Kidney and Transplant Specialised Register up to 18 December 2017 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov. SELECTION CRITERIA: We included all randomised or quasi-randomised control trials (RCTs) comparing antimicrobial (antibiotic and non-antibiotic) lock solutions to standard lock solutions, in participants using a CVC for HD, without language restriction. DATA COLLECTION AND ANALYSIS: Two authors independently assessed studies for eligibility, and two additional authors assessed for risk of bias and extracted data. We expressed results as rate ratios (RR) per 1000 catheter-days or 1000 dialysis sessions with 95% confidence intervals (CI). Statistical analyses were performed using the random-effects model. MAIN RESULTS: Thirty-nine studies, enrolling 4216 participants, were included in this review, however only 30 studies, involving 3392 participants, contained enough data to be meta-analysed. Risk of bias was low or unclear for most domains in the majority of the included studies.Studies compared antimicrobial lock solutions (antibiotic and non-antibiotic) to standard sealing solutions (usually heparin) of the CVC for HD. Fifteen studies used antibiotic lock solutions, 21 used non-antibiotic antimicrobial lock solutions, and 4 used both (antibiotic and non-antibiotic) lock solutions. Studies reported the incidence of CRI, catheter thrombosis, or both.Antimicrobial lock solutions probably reduces CRI per 1000 catheter-days (27 studies: RR 0.38, 95% CI 0.27 to 0.53; I2 = 54%; low certainty evidence), however antimicrobial lock solutions probably makes little or no difference to the risk of thrombosis per 1000 catheter days (14 studies: RR 0.79, 95% CI 0.52 to 1.22; I2 = 83%; very low certainty evidence). Subgroup analysis of antibiotic and the combination of both lock solutions showed that both probably reduced CRI per 1000 catheter-days (13 studies: RR 0.30, 95% CI: 0.22 to 0.42; I2 = 47%) and risk of thrombosis per 1000 catheter-days (4 studies: RR 0.26, 95% CI: 0.14 to 0.49; I2 = 0%), respectively. Non-antibiotic antimicrobial lock solutions probably reduced CRI per 1000 catheter-days for tunnelled CVC (9 studies: RR 0.60, 95% CI 0.40 to 0.91) but probably made little or no difference with non-tunnelled CVC (4 studies: RR 0.93, 95% CI 0.48 to 1.81). Subgroup analyses showed that antibiotic (5 studies: RR 0.76, 95% CI 0.42 to 1.38), non-antibiotic (8 studies: RR 0.85, 95% CI 0.44 to 1.66), and the combination of both lock solutions (3 studies: RR 0.63, 95% CI 0.22 to 1.81) made little or no difference to thrombosis per 1000 catheter-days compared to control lock solutions. AUTHORS' CONCLUSIONS: Antibiotic antimicrobial and combined (antibiotic-non antibiotic) lock solutions decreased the incidence of CRI compared to control lock solutions, whereas non-antibiotic lock solutions reduce CRI only for tunnelled CVC. The effect on thrombosis incidence is uncertain for all antimicrobial lock solutions. Our confidence in the evidence is low and very low; therefore, better-designed studies are needed to confirm the efficacy and safety of antimicrobial lock solutions.

[Indoor air pollution by fine particulate matter in the homes of newborns]. / Contaminación intradomiciliaria por material particulado fino (MP2,5) en hogares de recién nacidos.

INTRODUCTION: Air pollution by particulate matter (PM) is a major public health problem. In Chile, the study has focused on outdoor air and PM10, rather than indoor air and PM2.5. Because newborns and infants spend most of their time at home, it is necessary to evaluate the exposure to indoor air pollution in this susceptible population. OBJECTIVE: To determine concentration of PM2.5 in the homes of newborns and identify the emission sources of the pollutants. PATIENTS AND METHOD: The PM2.5 concentration ([PM2.5]) was collected over a 24hour period in 207 households. Baseline sociodemographic information and environmental factors (heating, ventilation, smoking and house cleaning), were collected. RESULTS: The median [PM2.5] was 107.5µg/m3. Family history of asthma was associated with lower [PM2.5] (P=.0495). Homes without heating showed a lower median [PM2.5], 58.6µg/m3, while those using firewood, kerosene, and electricity ranged between 112.5 and 114.9, and coal users' homes reached 162.9µg/m3. Wood using homes had significant differences (P=.0164) in median [PM2.5] whether the stove had complete combustion (98.2µg/m3) vs. incomplete (112.6µg/m3), or a salamander stove (140.6µg/m3). Cigarette smoking was reported in 8.7% of the households, but was not associated with the [PM2.5]. Ventilation was associated with a higher median [PM2.5] (120.6 vs. 99.1µg/m3, P=.0039). CONCLUSION: We found homes with high [PM2.5]. Residential wood consumption was almost universal, and it is associated with the [PM2.5]. Natural ventilation increased MP2.5, probably due to infiltration from outside.

Person-to-person household and nosocomial transmission of andes hantavirus, Southern Chile, 2011.

Andes hantavirus (ANDV) causes hantavirus cardiopulmonary syndrome in Chile and is the only hantavirus for which person-to-person transmission has been proven. We describe an outbreak of 5 human cases of ANDV infection in which symptoms developed in 2 household contacts and 2 health care workers after exposure to the index case-patient. Results of an epidemiologic investigation and sequence analysis of the virus isolates support person-to-person transmission of ANDV for the 4 secondary case-patients, including nosocomial transmission for the 2 health care workers. Health care personnel who have direct contact with ANDV case-patients or their body fluids should take precautions to prevent transmission of the virus. In addition, because the incubation period of ANDV after environmental exposure is longer than that for person-to-person exposure, all persons exposed to a confirmed ANDV case-patient or with possible environmental exposure to the virus should be monitored for 42 days for clinical symptoms.

Viral shedding and viraemia of Andes virus during acute hantavirus infection: a prospective study.

BACKGROUND: Andes virus (ANDV) is a zoonotic Orthohantavirus leading to hantavirus cardiopulmonary syndrome. Although most transmissions occur through environmental exposure to rodent faeces and urine, rare person-to-person transmission has been documented, mainly for close contacts. This study investigates the presence and infectivity of ANDV in body fluids from confirmed cases and the duration of viraemia. METHODS: In this prospective study, 131 participants with confirmed ANDV infection were enrolled in Chile in a prospective study between 2008 and 2022. Clinical samples (buffy coat, plasma, gingival crevicular fluid [GCF], saliva, nasopharyngeal swabs [NPS], and urine) were collected weekly for 3 weeks together with clinical and epidemiological data. Samples were categorised as acute or convalescent (up to and after 16 days following onset of symptoms). Infectivity of positive fluids was assessed after the culture of samples on Vero E6 cells and use of flow cytometry assays to determine the production of ANDV nucleoprotein. FINDINGS: ANDV RNA was detected in 100% of buffy coats during acute phase, declining to 95% by day 17, and to 93% between days 23-29. ANDV RNA in GCF and saliva decreased from 30% and 12%, respectively, during the acute phase, to 12% and 11% during the convalescent phase. Successful infectivity assays of RT-qPCR-positive fluids, including GCF, saliva, NPS, and urine, were observed in 18 (42%) of 43 samples obtained during the acute phase of infection. After re-culture, the capacity to infect Vero E6 cells was maintained in 16 (89%) of 18 samples. Severity was associated with the presence of ANDV RNA in one or more fluids besides blood (odds ratio 2·58 [95% CI 1·42-5·18]). INTERPRETATION: ANDV infection is a systemic and viraemic infection, that affects various organs. The presence of infectious particles in body fluids contributes to our understanding of potential mechanisms for person-to-person transmission, supporting the development of preventive strategies. Detection of ANDV RNA in additional fluids at hospital admission is a predictor of disease severity. FUNDING: National Institutes of Health and Agencia de Investigación y Desarrollo. TRANSLATION: For the Spanish translation of the abstract see Supplementary Materials section.

High-dose intravenous methylprednisolone for hantavirus cardiopulmonary syndrome in Chile: a double-blind, randomized controlled clinical trial.

BACKGROUND: Andes virus (ANDV)-related hantavirus cardiopulmonary syndrome (HCPS) has a 35% case fatality rate in Chile and no specific treatment. In an immunomodulatory approach, we evaluated the efficacy of intravenous methylprednisolone for HCPS treatment, through a parallel-group, placebo-controlled clinical trial. METHODS: Patients aged >2 years, with confirmed or suspected HCPS in cardiopulmonary stage, admitted to any of 13 study sites in Chile, were randomized by study center in blocks of 4 with a 1:1 allocation and assigned through sequentially numbered envelopes to receive placebo or methylprednisolone 16 mg/kg/day (≤1000 mg) for 3 days. All personnel remained blinded except the local pharmacist. Infection was confirmed by immunoglobulin M antibodies or ANDV RNA in blood. The composite primary endpoint was death, partial pressure of arterial oxygen/fraction of inspired oxygen ratio ≤55, cardiac index ≤2.2, or ventricular tachycardia or fibrillation within 28 days. Safety endpoints included the number of serious adverse events (SAEs) and quantification of viral RNA in blood. Analysis was by intention to treat. RESULTS: Infection was confirmed in 60 of 66 (91%) enrollees. Fifteen of 30 placebo-treated patients and 11 of 30 methylprednisolone-treated patients progressed to the primary endpoint (P = .43). We observed no significant difference in mortality between treatment groups (P = .41). There was a trend toward more severe disease in placebo recipients at entry. More subjects in the placebo group experienced SAEs (P = .02). There were no SAEs clearly related to methylprednisolone administration, and methylprednisolone did not increase viral load. CONCLUSIONS: Although methylprednisolone appears to be safe, it did not provide significant clinical benefit to patients. Our results do not support the use of methylprednisolone for HCPS. CLINICAL TRIALS REGISTRATION: NCT00128180.

Childhood asthma and allergies in urban, semiurban, and rural residential sectors in Chile.

While rural living protects from asthma and allergies in many countries, results are conflicting in Latin America. We studied the prevalence of asthma and asthma symptoms in children from urban, semiurban, and rural sectors in south Chile. A cross-sectional questionnaire study was conducted in semiurban and rural sectors in the province of Valdivia (n = 559) using the ISAAC (International Study of Asthma and Allergies in Childhood) questionnaire. Results were compared to prevalence in urban Valdivia (n = 3105) by using data from ISAAC III study. Odds ratios (+95% confidence intervals) were calculated. No statistical significant differences were found for asthma ever and eczema symptoms stratified by residential sector, but a gradient could be shown for current asthma and rhinoconjunctivitis symptoms with urban living having highest and rural living having lowest prevalence. Rural living was inversely associated in a statistical significant way with current asthma (OR: 0.4; 95% CI: 0.2-0.9) and rhinoconjunctivitis symptoms (OR: 0.3; 95% CI: 0.2-0.7) in logistic regression analyses. Rural living seems to protect from asthma and respiratory allergies also in Chile, a South American country facing epidemiological transition. These data would be improved by clinical studies of allergic symptoms observed in studied sectors.

[Streptococcus suis meningitis in pig farmers: report of first two cases in Chile]. / Meningitis bacteriana aguda por Streptococcus suis en criadores de cerdos: comunicación de los primeros dos casos en Chile.

UNLABELLED: Human infection by Streptococcus suis is a zoonosis with a known occupational risk. Meningitis is its most frequent clinical manifestation. We present the first two cases in Chile. FIRST CASE: 54-year-old female patient, pig-farmer. She presented headache, vomiting, confusion and meningismus. She presented septic shock. Second case: 48-year-old male patient, also pig farmer, presented headache, vomiting and meningismus. A Gram's staining of cerebrospinal fluid (CSF) showed gram-positive cocci in both cases. Ceftriaxone and dexamethasone treatment was administered. The CSF cultures were positive for Streptococcus suis serotype 2. The patients experienced a good outcome, without neurological sequelae at the time of discharge. It is considerable to evaluate epidemiologic factors in order to suspect this etiological agent in cases of meningitis. These cases enhance the need of heighten awareness of potential for occupational exposure and infection by this emerging human pathogen. Educating population at risk about simple preventive measures must be considered.

Opinions, Attitudes and Factors Related to SARS-CoV-2 Vaccine Uptake in Eight South American Countries.

This article presents attitudes and practices regarding COVID-19 vaccination in the South American population. The study collected data from a self-administered survey distributed through social media platforms between February and April 2022 (N = 6555). The survey included questions related to participants' sociodemographic background, flu vaccination practices, sources of information about COVID-19, and opinions regarding pandemic management and vaccination against SARS-CoV-2. The respondents agreed with the statement that COVID-19 vaccines were necessary (86.4%), effective (79.8%), safe (79.1%), and should be mandatory (64%). Overall, 83.4% accepted vaccination and 12.3% refused it completely. Main rejection reasons were safety (65.8%) and efficacy (54.9%) issues, and rushed development and approvals (49.1%). Vaccine uptake was associated with being ≥60 years, being a healthcare worker, previous influenza vaccine uptake, adherence to preventive measures, the death of ≥1 close people from COVID-19, and being informed through mass media or health authorities' channels. Vaccine uptake inversely correlated with male gender, low educational level, and use of closed social networks for COVID-19 information purposes. This study provides valuable insights into COVID-19 vaccination attitudes and practices in South America that may be used to promote vaccine uptake in the region. Higher COVID-19 vaccination acceptance among people with previously acquired prevention habits reinforces the importance of routine health promotion strategies.

Different Safety Pattern of an Inactivated SARS-CoV-2 Vaccine (CoronaVac®) According to Age Group in a Pediatric Population from 3 to 17 Years Old, in an Open-Label Study in Chile.

During the COVID-19 pandemic, the importance of vaccinating children against SARS-CoV-2 was rapidly established. This study describes the safety of CoronaVac® in children and adolescents between 3- and 17-years-old in a multicenter study in Chile with two vaccine doses in a 4-week interval. For all participants, immediate adverse events (AEs), serious AEs (SAEs), and AEs of special interest (AESIs) were registered throughout the study. In the safety subgroup, AEs were recorded 28 days after each dose. COVID-19 surveillance was performed throughout the study. A total of 1139 individuals received the first and 1102 the second dose of CoronaVac®; 835 were in the safety subgroup. The first dose showed the highest number of AEs: up to 22.2% of participants reported any local and 17.1% systemic AE. AEs were more frequent in adolescents after the first dose, were transient, and mainly mild. Pain at the inoculation site was the most frequent AE for all ages. Fever was the most frequent systemic AE for 3-5 years old and headache in 6-17 years old. No SAEs or AESIs related to vaccination occurred. Most of the COVID-19 cases were mild and managed as outpatients. CoronaVac® was safe and well tolerated in children and adolescents, with different safety patterns according to age.

Possible association between Guillain-Barré syndrome and SARS-CoV-2 infection in children: A case report and literature review.

Neurological manifestations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have been reported in adults and in children, varying from mild to more debilitant symptoms, including fatigue, headache and dizziness. A series of studies have revealed a possible association between Guillain-Barré syndrome (GBS), the most common cause of acute flaccid paralysis at all ages, and SARS-CoV-2 infection. Case reports of novel coronavirus disease 2019 (COVID-19)-associated GBS mainly include adult patients, while only a few pediatric cases have been reported. The present study describes a case of GBS in an Italian 9-year-old girl with previous SARS-CoV-2 infection as a possible trigger, and also conducts a literature review on pediatric COVID-19-associated GBS cases.

IgG targeting distinct seasonal coronavirus- conserved SARS-CoV-2 spike subdomains correlates with differential COVID-19 disease outcomes.

Despite SARS-CoV-2 being a "novel" virus, early detection of anti-spike IgG in severe COVID-19 patients may be caused by the amplification of humoral memory responses against seasonal coronaviruses. Here, we examine this phenomenon by characterizing anti-spike IgG responses in non-hospitalized convalescent individuals across a spectrum of COVID-19 severity. We observe that disease severity positively correlates with anti-spike IgG levels, IgG cross-reactivity against other betacoronaviruses (ß-CoVs), and FcγR activation. Analysis of IgG targeting ß-CoV-conserved and non-conserved immunodominant epitopes within the SARS-CoV-2 spike protein revealed epitope-specific relationships: IgG targeting the conserved heptad repeat (HR) 2 region significantly correlates with milder disease, while targeting the conserved S2'FP region correlates with more severe disease. Furthermore, a lower HR2-to-S2'FP IgG-binding ratio correlates with greater disease severity, with ICU-hospitalized COVID-19 patients showing the lowest HR2/S2'FP ratios. These findings suggest that HR2/S2'FP IgG profiles may predict disease severity and offer insight into protective versus deleterious humoral recall responses.

Sustained Antibody-Dependent NK Cell Functions in Mild COVID-19 Outpatients During Convalescence.

The coronavirus disease 2019 (COVID19) pandemic has left researchers scrambling to identify the humoral immune correlates of protection from COVID-19. To date, the antibody mediated correlates of virus neutralization have been extensively studied. However, the extent that non-neutralizing functions contribute to anti-viral responses are ill defined. In this study, we profiled the anti-spike antibody subtype/subclass responses, along with neutralization and antibody-dependent natural killer cell functions in 83 blood samples collected between 4 and 201 days post-symptoms onset from a cohort of COVID-19 outpatients. We observed heterogeneous humoral responses against the acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein. Overall, anti-spike profiles were characterized by a rapid rise of IgA and sustained IgG titers. In addition, strong antibody-mediated natural killer effector responses correlated with milder disease and being female. While higher neutralization profiles were observed in males along with increased severity. These results give an insight into the underlying function of antibodies beyond neutralization and suggest that antibody-mediated natural killer cell activity is a key function of the humoral response against the SARS-CoV-2 spike protein.

Inactivated Vaccine-Induced SARS-CoV-2 Variant-Specific Immunity in Children.

Multiple vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been evaluated in clinical trials. However, trials addressing the immune response in the pediatric population are scarce. The inactivated vaccine CoronaVac has been shown to be safe and immunogenic in a phase 1/2 clinical trial in a pediatric cohort in China. Here, we report interim safety and immunogenicity results of a phase 3 clinical trial for CoronaVac in healthy children and adolescents in Chile. Participants 3 to 17 years old received two doses of CoronaVac in a 4-week interval until 31 December 2021. Local and systemic adverse reactions were registered for volunteers who received one or two doses of CoronaVac. Whole-blood samples were collected from a subgroup of 148 participants for humoral and cellular immunity analyses. The main adverse reaction reported after the first and second doses was pain at the injection site. Four weeks after the second dose, an increase in neutralizing antibody titer was observed in subjects relative to their baseline visit. Similar results were found for activation of specific CD4+ T cells. Neutralizing antibodies were identified against the Delta and Omicron variants. However, these titers were lower than those for the D614G strain. Importantly, comparable CD4+ T cell responses were detected against these variants of concern. Therefore, CoronaVac is safe and immunogenic in subjects 3 to 17 years old, inducing neutralizing antibody secretion and activating CD4+ T cells against SARS-CoV-2 and its variants. (This study has been registered at ClinicalTrials.gov under no. NCT04992260.) IMPORTANCE This work evaluated the immune response induced by two doses of CoronaVac separated by 4 weeks in healthy children and adolescents in Chile. To date, few studies have described the effects of CoronaVac in the pediatric population. Therefore, it is essential to generate knowledge regarding the protection of vaccines in this population. Along these lines, we reported the anti-S humoral response and cellular immune response to several SARS-CoV-2 proteins that have been published and recently studied. Here, we show that a vaccination schedule consisting of two doses separated by 4 weeks induces the secretion of neutralizing antibodies against SARS-CoV-2. Furthermore, CoronaVac induces the activation of CD4+ T cells upon stimulation with peptides from the proteome of SARS-CoV-2. These results indicate that, even though the neutralizing antibody response induced by vaccination decreases against the Delta and Omicron variants, the cellular response against these variants is comparable to the response against the ancestral strain D614G, even being significantly higher against Omicron.

Environmental risk factors in the first year of life and childhood asthma in the Central South of Chile.

BACKGROUND: Childhood asthma has a high prevalence in South America--a region of the world currently undergoing a thorough modernization and transition process. Asthma in South America is mainly associated with poor urban environment, which actually may challenge the role of the hygiene hypothesis. We systematically assessed the impact of environmental factors in the first year of life on asthma. METHODS: A case-control study including 188 asthmatics and 294 hospital-based controls aged 6-15 years was carried out in the Central South of Chile. Parents of study participants completed a computer-assisted interview on environmental factors (such as birth order, day-care attendance, pneumonia infection, regular animal and furry pet contact, and environmental tobacco smoke exposure) in the first year of life and potential confounders. Atopy was assessed using skin prick tests. Multivariate logistic regression models were calculated to assess the association between exposures and asthma, adjusting for potential confounders. RESULTS: Day-care attendance (OR = 0.31; 95% CI: 0.10, 0.94) and regular farm animal contact (OR = 0.38; 95% CI: 0.17, 0.85) were inversely related to childhood asthma in the logistic regression models. Pneumonia infection (OR = 2.24; 95% CI: 1.21, 4.16) and mold or dampness in the home (OR = 1.87; 95% CI: 1.18, 2.97) in the first year of life were positively associated with asthma. CONCLUSION: Our results suggest that the hygiene hypothesis is also applicable in the Chilean setting, a South American country in epidemiological transition.

[Update. Consensus on ventilator associated pneumonia. Second Part: Prophylaxis]. / Actualización consenso neumonía asociada a ventilación mecánica. Segunda Parte. Prevención.

Ventilator associated pneumonia is a life threatening disease, in spite of advances in its treatment, consequently the development of prevention strategies is a key factor in improving the morbidity and mortality in intensive care units (ICU). The new developments in this field in the last years led to the need to update the recommendations done in 2001. Then, a new search and analysis of scientific literature was performed. The obtained data support different strategies highlighting: semi-recumbent position at 45 degrees of patients; incorporation of routinely oral hygiene procedures with chlorhexidine; preference of orotracheal intubation; performing subglotic aspiration; use of standard hand hygiene techniques; not routine change of ventilator circuits; and defining bundles to organize the work at ICU. Some strategies were recommended for being of similar efficacy to others but cost-effective as: use of heat and moisture humidificators; and changing humidificators every 5 to 7 days. The use of open or closed endotracheal suctioning system does not affect the incidence of pneumonia. Some recommendations were not incorporated because of lack of evidence supporting effectiveness, controversial data or doubtful application to our country as selective digestive decontamination.

[Etiology of pneumonia in chilean HIV-infected adult patients]. / Etiología de la neumonía en pacientes chilenos infectados por el virus de la inmunodeficiencia humana.

OBJECTIVES: To establish the etiology of pneumonia and to compare the yield of diagnostic techniques for diagnosis of Pneumocystis jiroveci and Mycobacterium tuberculosis infections in HIV-1-infected patients. PATIENTS AND METHODS: Subjects underwent sputum induction and bronchoalveolar lavage (BAL). Gram, Ziehl-Neelsen, silver stain (SS) and immunofluorescense staining (IF) for P. jiroveci, fluorescent stain for mycobacteria, PCR for P. jiroveci and M. tuberculosis, aerobic, fungal and mycobacterial cultures, respiratory viruses and CMV cultures were performed on the sputum and BAL. IgM for Mycoplasma pneumoniae and Chlamydophyla pneumoniae, and Legionella pneumophila urinary antigen were also obtained. RESULTS: Sixty patients were included. An etiologic diagnosis was made in 97%. Pneumocystis jiroveci was the most frequent etiology (58%) followed by Streptococcus pneumoniae (12%), and Mycobacterium avium complex (12%). Mycobacterium tuberculosis was found in 5%. CONCLUSIONS: The comparison of diagnostic methods for P. jiroveci showed a higher sensitivity of IF and SS in BAL than in sputum, however PCR was equally sensitive in both samples. With this approach a precise etiologic diagnosis was reached in the great majority of patients. The most common etiology was P. jiroveci. IF in BAL remains the gold standard for diagnosis of P. jiroveci pneumonia.

Proteinuria in Hantavirus Cardiopulmonary Syndrome: A Frequent Finding Linked To Mortality.

OBJECTIVES: To determine the relative frequency and prognosis value of proteinuria in hantavirus cardiopulmonary syndrome (HCPS) due to Andes virus. METHODS: This observational analytical study prospectively obtained data from patients admitted to 12 health centers in nine Chilean cities between 2001 and 2018. Only patients with confirmed Andes virus HCPS and laboratory characterization that included qualitative proteinuria determination at admission were considered. RESULTS: The database involved 175 patients, 95 of them had a measurement of urine protein at the time of hospital admission. They were mainly male (71%) and the median age was 35 [22-47] years. Median duration of the febrile prodromal time was 5 [4-7] days. Hospital length of stay and hospital mortality rate were 10 [7-14] days and 21.1%, respectively. Seventy-three patients (77%) were identified with proteinuria at admission, which was associated with increased mortality rate (26% versus 5%, p=0.036) and the relative risk was 1.3 [1.1-1.6], p=0.002. CONCLUSIONS: Proteinuria is a frequent finding in patients with HCPS, which is associated with a higher mortality rate.

Cytokine Profiles and Antibody Response Associated to Choclo Orthohantavirus Infection.

Background: New World Hantaviruses (NWHs) are the etiological agent underlying hantavirus cardiopulmonary syndrome (HCPS), a severe respiratory disease with high mortality rates in humans. In Panama, infections with Choclo Orthohantavirus (CHOV) cause a much milder illness characterized by higher seroprevalence and lower mortality rates. To date, the cytokine profiles and antibody responses associated with this milder form of HCPS have not been defined. Therefore, in this study, we examined immune serological profiles associated with CHOV infections. Methods: For this retrospective study, sera from fifteen individuals with acute CHOV-induced HCPS, were analyzed alongside sera from fifteen convalescent phase individuals and thirty-three asymptomatic, CHOV-seropositive individuals. Cytokine profiles were analyzed by multiplex immunoassay. Antibody subclasses, binding, and neutralization against CHOV-glycoprotein (CHOV-GP) were evaluated by ELISA, and flow cytometry. Results: High titers of IFNγ, IL-4, IL-8, and IL-10 serum cytokines were found in the acute individuals. Elevated IL-4 serum levels were found in convalescent and asymptomatic seropositive individuals. High titers of IgG1 subclass were observed across the three cohorts analyzed. Neutralizing antibody response against CHOV-GP was detectable in few acute individuals but was strong in both convalescent and asymptomatic seropositive individuals. Conclusion: A Th1/Th2 cytokine signature is characteristic during acute mild HCPS caused by CHOV infection. High expression of Th2 and IL-8 cytokines are correlated with clinical parameters in acute mild HCPS. In addition, a strong IL-4 signature is associated with different cohorts, including asymptomatic individuals. Furthermore, asymptomatic individuals presented high titers of neutralizing antibodies.