Resultados del primer bimestre de trabajo de la unidad de diagnóstico COVID-19 de la Facultad de Ciencias Veterinarias-UNLP

The COVID-19 pandemic required rapid development and approval of diagnostic methods and kits. Nasal swab samples (n=1114) were derived to Faculty of Veterinary Sciences- UNLP COVID-19 diagnostic unit by the Buenos Aires Province Ministry of Health during June and July 2020, to perform molecular diagnosis of SARS- CoV-2. Samples of RNA were purified in a type II biosafety cabin and analyzed by real time RT-PCR with the GeneFinder™ kit, which amplifies 3 viral target genes (N, E y RdRp). Of the 1110 samples with positive internal control, 458 (41.2%) were positive (26.9% to all target genes, 4.2% to 2 target genes and almost 10% to one gene, mainly N). Percentage of positive samples remained similar throughout the study period, although the sample number was higher in July (781 samples; 315 positive) compared to June (333 samples; 143 positive). Samples from Berisso, Ensenada and La Plata had significantly lower positive rate than those coming from other counties (27.6% versus 60.7%, respectively). Positivity rate was higher in samples from patients with ≥3 clinical signs (55.6%). It is necessary to conduct inter-laboratory validation studies and standardization of diagnostic methods used in order to obtain reliable and reproducible results.