SARS-CoV-2 variant detection relies on resource-intensive whole-genome sequencing methods. We sought to develop a scalable protocol for variant detection and surveillance in Paraguay, pairing rRT-PCR for spike mutations with Nanopore sequencing. A total of 201 acute-phase nasopharyngeal samples were included. Samples were positive for the SARS-CoV-2 N2 target and tested with the Spike SNP assay to detect mutations associated with the following variants: alpha (501Y), beta/gamma (417variant/484K/501Y), delta (452R/478K), and lambda (452Q/490S). Spike SNP calls were confirmed using amplicon (Sanger) sequencing and whole-genome (Nanopore) sequencing on a subset of samples with confirmed variant lineages. Samples had a mean N2 Ct of 20.8 (SD 5.6); 198/201 samples (98.5%) tested positive in the Spike SNP assay. The most common genotype was 417variant/484K/501Y, detected in 102/198 samples (51.5%), which was consistent with the P.1 lineage (gamma variant) in Paraguay. No mutations (K417 only) were found in 64/198 (32.3%), and K417/484K was identified in 22/198 (11.1%), consistent with P.2 (zeta). Seven samples (3.5%) tested positive for 452R without 478K, and one sample with genotype K417/501Y was confirmed as B.1.1.7 (alpha). The results were confirmed using Sanger sequencing in 181/181 samples, and variant calls were consistent with Nanopore sequencing in 29/29 samples. The Spike SNP assay could improve population-level surveillance for mutations associated with SARS-CoV-2 variants and inform the judicious use of sequencing resources.

Key words: Asymptomatic cases; Malaria; Paraguay

La importancia de determinar el sexo en especies monomórficas que viven en cautiverio conlleva a estrategias de apareamiento a fin de poder incentivar la reproducción. Existen métodos no moleculares de reconocimiento pero son factibles en edad adulta y mucho más difícil cuando son polluelos. Mediante la técnica molecular de PCR, se amplificó el gen de la Cromo Helicasa de Unión al ADN empleando los cebadores, 2550F/2718R. Por este método molecular se consiguió determinar el sexo en 19 de 23 especies de las cuales 3 son ejemplares de: Amazona aestiva, 1 de Pipile grayi, 1 de Bubo virginianus, 4 de Ara chloropterus, 6 de Crax fasciolata, 2 de Caracara plancus, 3 de Chauna torquata, 1 de Cariama cristata y 2 de Cairina moschata del Centro de Investigación de Animales Silvestres de ITAIPU binacional, del lado paraguayo. Nuestros resultados sugieren que el par de cebadores 2550F/2718R podría ser de utilidad para determinar el sexo en las especies estudiadas en el país.

Soon after the declaration of the COVID-19 pandemic, the Institute for Health Sciences Research (IICS) of the National University of Asunción, Paraguay became a testing laboratory (COVID-Lab) for SARS-CoV-2. The COVID-Lab testing performance was assessed from 1 April 2020 to 12 May 2021. The effect of the pandemic on the IICS and how the COVID-Lab contributed to the academic and research activities of the institute were also assessed. IICS researchers and staff adjusted their work schedules to support the COVID-Lab. Of the 13,082 nasopharyngeal/oropharyngeal swabs processed, 2704 (20.7%) tested positive for SARS-CoV-2 by RT-PCR. Of the individuals testing positive, 55.4% were female and 48.3% were aged 21–40 years. Challenges faced by the COVID-Lab were unstable reagent access and insufficient staff; shifting obligations regarding research, academic instruction, and grantsmanship; and the continuous demands from the public for information on COVID-19. The IICS provided essential testing and reported on the progress of the pandemic. IICS researchers gained better laboratory equipment and expertise in molecular SARS-CoV-2 testing but struggled to manage their conflicting educational and additional research obligations during the pandemic, which affected their productivity. Therefore, policies protecting the time and resources of the faculty and staff engaged in pandemic-related work or research are necessary components of healthcare emergency preparedness.

In Paraguay, no cases of Malaria have been recorded since 2011. Microscopy and the SnM-PCR technique were implemented to detect and characterize Plasmodium spp. both in mosquitoes and in humans residing in historically endemic areas of Paraguay, to evaluate the possibility of finding asymptomatic cases and/or Plasmodium parasites circulating in anophelines. Between 2013 and 2015, 361 human blood samples were collected on filter paper, and between 2016 and 2017, 938 female Anopheles mosquitoes were captured in 15 Paraguayan localities. All the diagnostic techniques showed negative results. We observed no asymptomatic case or Plasmodium circulating in vectors.

En países donde el Plasmodium ovale no es común, los microscopistas tienden a identificarlo de manera errónea como Plasmodium vivax. En este trabajo reportamos la identificación de la especie P. ovale curtisipor el método de PCR múltiple semianidada (SnM-PCR) y la secuenciación de la subunidad pequeña del gen del ARN 18S, en un paciente paraguayo de 44 años de edad que vino en el 2.013 de Guinea Ecuatorial, África occidental, a quien se le diagnosticó una infección por P. vivax por microscopía convencional. El empleo de métodos moleculares para la identificación de casos importados de infección con especies del género Plasmodium es uno de los objetivos principales en el control y la prevención de la malaria en Paraguay, teniendo en cuenta que el país se encuentra en fase de pre-eliminación de la enfermedad.