Clinical Validation of a Colorimetric Loop-Mediated Isothermal Amplification Using a Portable Device for the Rapid Detection of SARS-CoV-2.

Quick and reliable mass testing of infected people is an effective tool for the contingency of SARS-CoV-2. During the COVID-19 pandemic, Point-of-Care (POC) tests using Loop-Mediated Isothermal Amplification (LAMP) arose as a useful diagnostic tool. LAMP tests are a robust and fast alternative to Polymerase Chain Reaction (PCR), and their isothermal property allows easy incorporation into POC platforms. The main drawback of using colorimetric LAMP is the reported short-term stability of the pre-mixed reagents, as well as the relatively high rate of false-positive results. Also, low-magnitude amplification can produce a subtle color change, making it difficult to discern a positive reaction. This paper presents Hilab Molecular, a portable device that uses the Internet of Things and Artificial Intelligence to pre-analyze colorimetric data. In addition, we established manufacturing procedures to increase the stability of colorimetric RT-LAMP tests. We show that ready-to-use reactions can be stored for up to 120 days at -20 °C. Furthermore, we validated both the Hilab Molecular device and the Hilab RT-LAMP test for SARS-CoV-2 using 581 patient samples without any purification steps. We achieved a sensitivity of 92.93% and specificity of 99.42% (samples with CT ≤ 30) when compared to RT-qPCR.

Genetic Diversity of Norovirus in Children with Acute Gastroenteritis in Southwest Nigeria, 2015-2017.

Norovirus (NoV) is a leading cause of viral gastroenteritis globally, especially in children below five years. Epidemiological studies on the diversity of NoV in middle- and low-income countries, including Nigeria, are limited. This study aimed to determine the genetic diversity of NoV in children below five years with acute gastroenteritis at three hospitals in Ogun State, Nigeria. A total of 331 fecal samples were collected from February 2015 to April 2017, while 175 were randomly selected and analyzed using RT-PCR, partial sequencing and phylogenetic analyses of both the polymerase (RdRp) and capsid (VP1) genes. NoV was detected in 5.1% (9/175; RdRp) and 2.3% (4/175; VP1) of samples, with 55.6% (5/9) co-infection with other enteric viruses. A diverse genotype distribution was identified, and GII.P4 was the dominant RdRp genotype detected (66.7%), with two genetic clusters, followed by GII.P31 (22.2%). The rare GII.P30 genotype (11.1%) was detected at a low rate for the first time in Nigeria. Based on the VP1 gene, GII.4 was the dominant genotype (75%), with two variants, Sydney 2012 and possibly New Orleans 2009, co-circulating during the study. Interestingly, both intergenotypic, GII.12(P4) and GII.4 New Orleans(P31), and intra-genotypic, GII.4 Sydney(P4) and GII.4 New Orleans(P4), putative recombinant strains were observed. This finding suggests the first likely report of GII.4 New Orleans(P31) in Nigeria. In addition, GII.12(P4) was first described in Africa and globally in this study, to the best of our knowledge. This study provided insights into the genetic diversity of NoV circulating in Nigeria, which would be useful for ongoing and future vaccine design and monitoring of emerging genotypes and recombinant strains.

Young adults HIV-1 infected by vertical transmission in southern Brazil - Clinical, demographic, and virological features.

Combination antiretroviral therapy promotes longer life expectancy, making it possible for perinatally HIV-infected patients to achieve adulthood. Past therapy was not always optimized, suggesting that virological and host features may also play a role in survival. The aim of this study is to describe characteristics of HIV disease progression associated with virological features in adolescents perinatally that were HIV infected. A case series was conducted including 81 patients that were in follow-up at Hospital de Clínicas/Universidade Federal do Paraná, Curitiba, Brazil. Venous blood was collected to conduct tropism and viral subtype assays. The median age was 19 years old (interquartile range 18-21), and a majority of patients were female (54.3%). Viral subtype was obtained for 66 (82%) patients, and subtypes B and C were found in 34% and 59%, respectively. Tropism assay was conducted in 55 (67%) patients: 71% were R5 and 29% X4. Distribution of viral tropism and subtype shows a significant association of subtype C with R5 tropism. Subtype C is more prevalent in southern Brazil and also in the population infected with HIV by vertical transmission. Both R5 tropism and subtype C are associated with slower progression to AIDS. The survival of these patients may be related to virological features present in a benign pattern of disease progression.

Molecular characterization and clinical epidemiology of human respiratory syncytial virus (HRSV) A and B in hospitalized children, Southern Brazil.

Human respiratory syncytial virus (HRSV) is a major etiologic agent of pediatric respiratory infections. Genetic variability of its glycoprotein G enables HRSV to evade the immune response and determines its seasonal dissemination. This study reports genetic variability and clinical profiles of HRSV-infected patients from Southern Brazil. Seventy positive samples, 78% type A and 22% type B, were analyzed. Of the patients (median age, 6 months; interquartile range, 2-11 years), 16% had co-morbidities and 17% developed severe disease. The ON1 HRSV genotype first appeared in 2012, and patients infected with this genotype showed an increased tendency to develop severe disease.

Paralisia cerebral diagnóstico etiológico / Cerebral palsy aetiologic diagnosis

Em estudo retrospectivo foram analisados 35 prontuários, obtidos ao acaso, de crianças com diagnóstico de Paralisia Cerebral (PC), atendidas no Hospital das Clínicas de Ribeirão Preto, entre 1982 e 1998, com o objetivo de verificar fatores etiológicos. As infecções congênitas (36 por cento) e agressão hipóxico-isquêmica (28 por cento) foram os mais freqüentes fatores determinantes de PC entre 25 casos com etiologia definida. Estes achados podem ser utilizados para estratégias regionais de prevenção de deficiências. Para os casos sem etiologia definida, lembram-se as formas herdadas de paralisia cerebral e o diagnóstico diferencial com doenças degenerativas