Porcine circovirus 3 ( PCV 3) was recently discovered and is a new species of the genus circovirus. Clinically, it is associated with absence of symptoms or with different clinical syndromes. It has been reported in different countries of America, Europe and Asia. Last year, in Colombia, some farms have reported symptoms similar to those caused by PCV 2. Samples were taken from two farms located in the centre of the country, and the presence of PCV 3 was determined by PCR in two samples, one from a pool of sera and another from mesenteric lymph node. The strains were fully sequenced (GenBank accession numbers MH 327784 and MH 327785) and classified into subgroups a1 and a2. According to this classification and its analysis, strain a2 is located within the group called “Linker” that may be evolving towards group “b”. In addition to the above, the two Colombian strains were compared with 104 strains reported in the GenBank database. The phylogenetic tree obtained grouped according to the classification of subgroups a1, a2, b1 and b2. It was found that subgroups a1 and a2 were well grouped when comparing whole genomes, but the same was not observed with the strains of group “b”. In the latter, no subgroups were evidenced when comparing complete genomes. It is suggested that a new classification of PCV 3 subgroups should be proposed, based on whole genome sequences. This is the first report of PCV 3 in Colombia and its complete genome sequence.

The emergence of the SARS-CoV-2 virus and the exponential growth of COVID-19 cases have created a major crisis for public health systems. The critical identification of contagious asymptomatic carriers requires the isolation of viral nucleic acids, reverse transcription, and amplification by PCR. However, the shortage of specific proprietary reagents or the lack of automated platforms have seriously hampered diagnostic throughput in many countries. Here, we provide a procedure for SARS-CoV-2 detection for diagnostic purposes from clinical samples in the setting of a basic research molecular biology lab. The procedure details the necessary steps for daily analysis of up to 500 clinical samples with a team composed of 12 experienced researchers. The protocol has been designed to rely on widely available reagents and devices, to cope with heterogeneous clinical specimens, to guarantee nucleic acid extraction from very scarce biological material, and to minimize the rate of false-negative results.

To better understand plausible SARS-CoV-2 transmission through fomites, a physiological model was designed to analyze the decay rate of SARS-CoV-2 infectivity. We focused on non-porous materials present in high-touch surfaces or used as containment barrier surfaces, namely glass, acrylic glass, photo-activated coated glass, stainless steel and aluminium. SARS-CoV-2 survival depended on the material considered, with half-lives on glass, photo-activated coated glass, stainless steel and aluminium equal to 6.9, 4.1, 3.5 and 2.3 h, respectively. This study highlights the potential utility of coatings in the fight against the current threat. In addition, it spotlights the need for standardizing assays to assess indirect transmission of COVID-19.