Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Background: COVID-19, caused by the severe acute respiratory syndrome virus type-2 (SARS-CoV-2), was declared a pandemic in March 2020. Seroprevalence studies are useful to estimate the proportion of the population previously infected, quantify the magnitude of transmission, estimate the fatality rate, evaluate the effect of interventions, and estimate the degree of immunity of the population. Aim:  To determine the extension of the infection and the cumulative incidence of age-specific infection, determined by seropositivity in the population of the sanitary regions of Asunción and the Central Department of Paraguay. Methods: Population-based cohort study. In Asunción 126 households and in the Central Department 609 were surveyed between December 2020 to March 2021. Three visits were made to the selected households. Results: The testing rate was 66.6%, 1,699 people (324 in Asunción and 1,375 in Central) of the 2,553 people registered. In the first, second and third rounds, seroprevalences were 15.5%, 15.4% and 14.3% in Asunción, respectively; in Central 23.1%, 27.8% and 26.9%, respectively. There was a seroconversion between the first and second rounds of 5.9%, and in the third round 6.5%; the accumulated global seroprevalence was 26.9% (95% CI: 24.8-19.1); in Asunción 23.1% (95% CI: 18.9-28.0) and in Central 27.8% (95% CI: 25.5-30.2). 8.5% of the participants reported symptoms; of them, 54.2% had positive serology. Conclusion: The sero-prevalence was high with a low proportion of people with symptoms.

SARS-CoV-2 infection in the pediatric population usually manifests with mild symptoms; however, in patients with comorbidities, there may be a severe pulmonary compromise. We present the case of a 3-month-old patient with acute SARS-CoV-2 infection, with persistent respiratory symptoms up to 8 weeks after the initial infection, with a persistently positive PCR test, requiring several hospitalizations, supplemental oxygen, and even invasive mechanical ventilation. Clinical and radiological manifestations were found consistent with bronchiolitis obliterans associated with SARS-CoV-2 infection. An adequate clinical response was documented after starting first-line treatment for bronchiolitis obliterans with satisfactory evolution during follow-up to date, evidencing the importance of considering this association in clinical practice.

El género Prototheca fue descrito inicialmente por Krüger en 1894, pertenece a la clase Trebouxiophyceae, orden Chlorellales y familia Chlorellaceae. Está constituido por algas aérobicas, sin clorofila, ubicuas en distintos sustratos naturales como resinas de arboles, tierra, bebederos de animales, establos, superficie de algunos alimentos, ambientes acuáticos con vegetales en descomposición y en los intestinos de animales. Pueden contaminar productos derivados como quesos, mantequillas y la leche. Se han descrito infecciones cutáneas y sistémicas por estos agentes en perros y gatos, además de mastitis en bovinos.En humanos puede colonizar la piel, las uñas, el tracto respiratorio y el sistema digestivo. Se han reportado todo tipo de infecciones por estos agentes, desde sistémicas graves en pacientes inmunocomprometidos hasta cutáneas y bursitis secundarias a traumas.

La infección por el virus de la hepatitis B (VHB) es un problema de gran impacto en la salud pública en el mundo1. Aproximadamente un tercio de la población mundial ha estado expuesta al virus y entre 250 a 290 millones de personas tienen infección crónica por VHB (persistencia de HBsAg por al menos 6 meses). La Organización Mundial de la Salud estimó para el año 2019 aproximadamente 820.000 defunciones, debido a complicaciones del VHB como cirrosis o carcinoma hepatocelular2.

Background: The cycle threshold (Ct) of real-time reverse transcription PCR (RT-qPCR) indicates the relative concentration of an RNA sequence, this value has been related to clinical profile in viral infections. Aim: To determine the correlation between the Ct value and the clinical classification of COVID-19. Method: A correlational cross-sectional study was carried out, the Ct values were obtained by RT-qPCR directed to the N gene of SARS-CoV-2, grouping them by means of a central robust estimator and related to the clinical classification of COVID-19. Results: Of the 718 cases included in the study; 77.7% (558) were mild; 21.3% (153) moderate and 1% (7) severe. The Ct value was grouped into levels: low Ct ≤ 18.83; medium Ct> 18.83- 30.10 and high Ct> 30.10. There was a weak inverse significant correlation (p = 0.002; Spearman's rho = -0.117) between the Ct value and the clinical classification. The characteristics: sex, age under 65 years, fever, chills, diarrhea, anosmia, and overweight-obesity were associated with the Ct value. Conclusion: The lower the Ct value, a classification of greater severity of COVID-19 is expected, however, because the correlation is weak, its usefulness as a severity predictor is limited.

Background: Despite the proven efficacy and safety of COVID-19 vaccines, pediatric vaccination coverage remains low in many countries. There are still doubts and fears in parents about vaccination in their children under 12 years of age. Aim: To evaluate the perceptions and intention of parents to vaccinate their children under 12 years of age. Methods: Analytical cross-sectional study based on an online survey that evaluated the parents’ perceptions regarding the risk of COVID-19 infection, the need for a vaccine, and the vaccine adverse events in their children under 12 years. We assessed the factors associated with the intention to vaccinate through crude (cPR) and adjusted prevalence rates (aPR), with confidence interval of 95% (CI 95%). Results: 83.5% of respondents had the intention to vaccinate their children under 12 years of age. In the multivariate analysis, the factors associated with a decrease in the intention to vaccinate were to believe that the vaccine was not necessary (aPR 0.65; 95% CI 0.44 – 0.94), that it would not protect (aPR: 0.14; 95% CI 0.03 – 0.63), it would not be safe (aPR: 0.80; 95% CI 0.70 – 0.92) and it would cause long-term side effects (aPR: 0.92; 95% CI 0.85 – 1.00). On the other hand, living on the highlands or jungle was associated with an increase in the intention. Conclusions: In Peru, 16.5% of parents would not vaccinate their children under 12 years of age, because they perceived that the vaccine was not necessary and would not protect against COVID-19. In addition, they expressed concerns about the development of possible adverse events.

Background: Human anisakidosis is a food-borne zoonosis, caused by the intake of fish meat parasitized by anisakid nematodes. Research of anisakids parasites in commercialized fish, without previous cooking or freezing, in the south central region of Chile is scarce. Aim: To identify anisakid nematodes in fourteen species of marine fish, obtained by artisanal fishing and commercialized in Concepción, Talcahuano and Lebu, cities from Bío Bío Region, Chile. Methods: During 2018 to 2020, we examinated for anisakids to 334 fresh marine fishes. Results: Larvae of Anisakis spp. and Pseudoterranova sp. were identified in specimens of seven and four fish species, respectively. Most of the larvae were found alive and located at the visceral level. Conclusion: Most of the positive fish species are recognized intermediate hosts for these parasites. The presence of anisakids in the musculature of these species indicates that their preparation, in smoked or raw form, is a risk to public health, and it is recommended to buy these products in gutted and / or frozen form, together with promoting their cooking.

This article reviews the main ethical challenges posed by human genome research in the light of the international literature and provides recommendations on how to approach them based on our experience in the Ethics Committee for Research on Human Subjects of the Faculty of Medicine, University of Chile, including national legal regulations. Ethical standards in human research must be extreme, in order to adequately protect participants in studies involving genomics. Particularly relevant in this context are the protection of confidentiality and anonymity; the policy of delivery of results and the possibility of withdrawing from the study.  Sharing data resulting from genetic research optimizes resources, provides greater transparency, and replicability of the analyses and makes it possible to discover genetic alterations responsible for rare diseases and genes involved in multifactorial hereditary diseases, as well as contributing to the design of precision medicine and new therapeutic strategies.  However, it poses great challenges: protecting privacy and avoiding re-identification of volunteers, delivery of results with pre- and post-study counseling. These aspects require the elaboration of a careful informed consent process for genomic research, the main components of which are discussed in this article.