Omicron 2, 4 and 5: situation in Italy and the EU, latest news

Covid infections, the spotlights remain on Omicron and sub-variants. “Those who argue that if you become infected with Omicron are not so serious are profoundly mistaken. This virus is better not to encounter it,” Massimo Galli, former director of the infectious diseases department of the Sacco hospital in Milan, told Adnkronos Health. The latest news concerns Omicron 4 and 5 which have become variants of concern (Voc) in the EU. VARIANTS OF CONCERN – On 12 May, in fact, the European Center for Disease Prevention and Control Ecdc reclassified these two sub-lineages of the Omicron variant of Sars-CoV-2, BA.4 and BA.5, from variants of interest to Voc. BA.4 and BA.5 were first identified in South Africa in January and February 2022 respectively, and have since become the dominant variants in that area. The ECDC shows that both lineages contain specific mutations in the domain that binds the receptor of the Spike protein (Rbd) with respect to Omicron 2 (BA.2). Preliminary studies suggest a significant change in the antigenic properties of BA.4 and BA.5 compared to Omicron 1 and 2, especially compared to Omicron 1. CASE PORTUGAL – What Portugal shows is that there is a tendency to increase in proportions of variants for BA.5 in recent weeks, accompanied by an increase in the number of Covid cases and the positive rate on tests. The Portuguese National Institute of Health estimated that BA.5 already accounted for approximately 37% of positive cases as of May 8, 2022. The estimated daily growth advantage for BA.5 over BA.2 is 13%, in line with that reported from South Africa. Assuming this growth rate, ECDC highlights, BA.5 will become the dominant variant in Portugal by May 22, 2022. SITUATION IN ITALY – “In Italy on May 3, the Omicron variant” of Sars-CoV-2 “had a prevalence estimated at 100%, with the predominant sub-variant BA.2 “almost 94%” and the presence of some cases of the sub-variants BA.4 and BA.5 “. This is the photograph taken by the flash survey conducted by the Higher Institute of Health and the Ministry of Health, together with the regional laboratories and the Bruno Kessler Foundation. For the rapid survey, the laboratories of regions and autonomous provinces were asked to select sub-samples of Covid-positive cases and to sequence the genome of the virus. The sample requested was chosen by Regions / Pa at random from among the positive samples, ensuring a certain geographical representativeness and, if possible, for different age groups. All Regions / Pa took part in the survey, for a total of 112 laboratories that sequenced 1,799 samples. These are the estimated prevalences: BA.1 is 3.5% (range 0-12.9%); BA.2 at 93.8% (65.6-100%); BA.3 below 0.1% (0-0.9%); BA.4 almost 0.5% (0-4%); BA.5 at 0.4% (0-5.6%). Also present were some recombinants of Omicron 1 and 2: XJ at 0.66%; XM at 0.59%; XN at 0.15%; XQ and XT below 0.1%. STAND OUT SARDINIA CASE – In an Italy where Omicron sub-variant 2 (BA.2) has almost canceled all its ‘sisters’, the case of Sardinia stands out, where BA.2 sets the minimum record (65.57%) and where two Omicron recombinants 1 and 2 seem to run: the XJ and XM mix mutants; both well above 10%, at 19.67% and 14.75% respectively, according to the latest flash survey. 100% in 5 autonomous regions / provinces (Basilicata, Molise, Bolzano, Trento and Valle d’Aosta). Omicron sub-variants 4 and 5 (BA.4 and BA.5), in the spotlight for a fifth wave of Covid in South Africa, are present in 7 regions (4 and 3 respectively). BA.4 reaches a peak of 4.02% in Emilia Romagna, followed by Calabria (2.86%), Tuscany (1.03%) and Lombardy (0.96%); BA.5 is almost 6% in Umbria (5.56%), followed by Puglia (3.23%) and Lazio (0.92%).