Asunto(s)
COVID-19 , Pandemias , SARS-CoV-2/genética , Brasil/epidemiología , COVID-19/epidemiología , COVID-19/virología , HumanosRESUMEN
Brazil currently ranks second in absolute deaths by COVID-19, even though most of its population has completed the vaccination protocol. With the introduction of Omicron in late 2021, the number of COVID-19 cases soared once again in the country. We investigated in this work how lineages BA.1 and BA.2 entered and spread in the country by sequencing 2173 new SARS-CoV-2 genomes collected between October 2021 and April 2022 and analyzing them in addition to more than 18,000 publicly available sequences with phylodynamic methods. We registered that Omicron was present in Brazil as early as 16 November 2021 and by January 2022 was already more than 99% of samples. More importantly, we detected that Omicron has been mostly imported through the state of São Paulo, which in turn dispersed the lineages to other states and regions of Brazil. This knowledge can be used to implement more efficient non-pharmaceutical interventions against the introduction of new SARS-CoV variants focused on surveillance of airports and ground transportation.
Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Brasil/epidemiología , Transportes , VacunaciónRESUMEN
BKV and JCV belong to the Polyomaviridae family and are opportunistic agents associated with complications in immunocompromised individuals. Although a single screening assay for both viruses would be convenient, the diversity of BKV and JCV serotypes and genotypes is a methodological challenge. In this paper, we developed a PCR method able to detect and segregate BKV and JCV, despite these genetic discrepancies. A duplex semi-nested PCR (duplex snPCR) was designed to target a conserved region (639nt-1516nt) within the VP2 gene. In the first PCR, a primer set common to all BKV and JCV serotypes/ genotypes was used, followed by a semi-nested PCR with internal primers for BKV and JCV segregation. The limit of detection of the duplex snPCR was as low as 10 copies of BKV or JCV plasmids/µL. Specific products were observed when JCV and BKV plasmids were mixed in the same reaction. In field sample testing, the duplex snPCR detected and distinguished both viruses in different biological samples. Results were confirmed by Sanger's sequencing. The geographical complexity of BKV and JCV serotypes and genotypes imposes limits to a simple and universal method that could detect each virus. However, we describe here a sensitive and reliable PCR technique for BKV and JCV diagnosis that overcomes these limitations and could be universally applied.
Asunto(s)
Virus BK/aislamiento & purificación , ADN Viral/genética , Virus JC/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Virus BK/clasificación , Virus BK/genética , Genotipo , Humanos , Virus JC/clasificación , Virus JC/genéticaRESUMEN
Pemphigus foliaceus (PF) is an autoimmune disease characterized by blistering of the skin. Infections caused by members of the herpesviridae family have been suggested as a possible triggering factor for pemphigus vulgaris (PV), but not for PF. The present study aimed to investigate the presence of Human herpesvirus (types 1, 2, 3) in corticosteroid refractory skin lesions from a patient with PF, by a Polymerase chain reaction (PCR) assay. The sample collected from cutaneous blisters has tested positive for herpes simplex virus type 1 (HSV1) after sequence analysis of the amplified viral genomic segment. The study concluded that when PF patients present corticosteroid or immunosuppressants refractory lesions, herpetic infection should be considered.