Derived from Delta and Omicron (formerly “Deltacron”), the XD variant is a recombinant of the covid virus. It is said to have infected 77 people in France but is no more dangerous than the Omicron BA.2 variant. What are the symptoms of the XD variant? Is it (more) dangerous? Know everything.
One can be infected with two Covid variants the same time. the variant XD is a recombinant issu of Delta et Omicron (ex-“Deltacron”). “Recombinant XD is always detected at low levels (0,2% during the Flash Week 16 survey (from April 18 to 24) and not detected in week 17 (25 avril-1er mai 2022)” noted Public Health France in the epidemiological point of May 12. 77 XD variant infections were investigated by the regional units of Public Health France according to the risk analysis of April 20. Eight hospitalizations have been reported but no cases of critical care or death with the XD variant. “This recombinant is detected at very low levels in France, which is in favor of a no competitive advantage of this variant compared to Omicron BA.2. Other Delta/Omicron recombinants, named XF and XShave emerged in other countries under similar circumstances“specifies the health organization. How many cases precisely in France? What profiles? Rather young people or older people? How to know if you have the XD variant ? What are the symptoms typical? More dangerous what Omicron? The latest info.
Definition: what is the XD variant?
“When two variants are circulating at the same time, some people can be infected with two variants simultaneously. These co-infections can lead to recombination phenomenathat is to say exchanges of genetic material between the two variants” recalls Public Health France. The recombinant therefore has a genome corresponding in part to that of the first variant and in part to that of the second variant. the variant XD was first detected in early January 2022, “it is indeed a recombinant because he has genetic characteristics from the two parental VOCs (variants) Delta and Omicron (BA.1)” informed Public Health France in its risk analysis of March 25. “Le Pangolin lineage XD was assigned to this recombinant et is now the official name of this recombinant (ex-Deltacron).” This variant has been classified as VUM (Variant Under Monitoring) i.e. “variant under evaluation”. The phenomenon of recombination is frequent for the SARS-CoV-2et its importance in public health depends on the similarity of the characteristics (transmissibility, pathogenicity, immune escape) between the two parental variants:
►If they have different characteristics, such as Delta and Omicron, enhanced monitoring is essential to determine the characteristics of the recombinant (transmissibility, pathogenicity, immune escape) likely to modify the dynamics of the COVID-19 epidemic.
► The more similar the parental variants are, the lower the probability that a recombinant will have different characteristics.
“No cases of the XD variant have affected people over the age of 70”
How many cases of XD variant in France?
In France, between December 2021 and January 2022, Delta/Omicron co-circulation was associated with the emergence of the XD recombinant. As of April 15, 77 cases of infection with the XD variant (54 confirmed cases and 23 suspected cases not sequenced but linked to a confirmed case) were investigated by the regional units of Public Health France. These sequences correspond to cases from several regions. The XD variant thus represents less than 0.1% of the interpretable sequences. “The median age of cases was 37 ans, the youngest case being 4 years old and the oldest 86 years old. The median age was similar to that of Omicron infection casesinvestigated between November 2021 and January 2022 “. Six cases of infection with the XD variant reported a previous infection by SARS-CoV-2 (8.1%), i.e. a lower proportion than for cases of infections by Omicron (14%).
What are the symptoms of the XD variant?
According to Public Health France, the The most common symptoms observed in people infected with the XD variant are: asthenia/fatigue (58%), headaches (56%), fever (46%), cough (42%) et sore throat (38%). The main difference with the cases of Omicron infections previously investigated is the higher rate ageusia [perte du goût] and anosmia [perte d’odorat].
“These recombinants are difficult to detect because it is not known at first sight whether we are dealing with a co-infection or a hybrid. This is high-flying work in genomics.e” indicates Professor Bruno Lina, virologist, on France Inter Tuesday, March 1, 2022. It is within the framework of the sequencing carried out during the Flash surveys that the first cases of co-infections and recombinations appeared. “In France, reinforced monitoring of Delta/Omicron co-infections has been set up in order to detect possible recombinants as soon as possible” added Public Health France. Before recalling the context: “Since the end of 2021, an Omicron wave has overlapped with a Delta wave in several regions of the world. This co-circulation of two variants on a large scale increases the probability of co-infections and therefore that of recombinants. Several suspected Delta/Omicron recombinants have been reported recently in the UK, USA and Australiaand others are under investigation“.
Is the XD variant more dangerous than Omicron?
The XD variant is not associated with a higher dangerousness than the variant Omicron or the Delta variant, according to the observations of the health authorities. Eight hospitalizations were reported among investigated cases of infection with the XD variant, four of whom were part of a hospital cluster and were hospitalized for a reason other than COVID-19. “No critical care admissions and no deathss have been reported, but longitudinal follow-up would be needed to confirm this“reports Santé Publique France on April 20.”This recombinant is detected at very low levels in France, which is in favor of a lack of competitive advantage of this variant compared to Omicron BA.2“adds the health organization.
Sources :
– Risk analysis related to emerging variants of Sars-Covid-2, April 20, 2022, Santé Publique France.
– Coronavirus : circulation of SARS-CoV-2 variants, Updated March 23, 2022, Public Health France.
– Flash surveys: evaluation of the circulation of SARS-CoV-2 variants in France, Updated on February 28, 2022, Public Health France.
