Omicron - The new SARS-CoV-2 challenge?

SARS-CoV-2 virus has infected nearly 300 M people worldwide and has been associated with over 6 M deaths by March 2022. Since the virus emergence in December 2019 in Wuhan, several new mutations have been described. The World Health Organization has developed a working name for these emerging variants according to their impact on the worldwide population. In this context a high alert has been paid to variants of concern (VOC) due to their high infectiousness and transmissibility patterns. The most recent VOC, Omicron (B.1.1.529), has become dominant in the shortest time ever and has placed Europe under an overwhelming and unprecedented number of new cases. This variant has numerous mutations in regions that are associated with higher transmissibility, stronger viral binding, affinity and antibody escape. Moreover, the mutations and deletions present in the spike protein suggest that the SARS-CoV-2 specific attachment inhibitors may not be the best option for Omicron therapy. Omicron is the dominant variant circulating worldwide and, at the end of February 2022, it was responsible for nearly all sequences reported to GISAID. Omicron is made up of several sublineages, where the most common are BA.1 and BA.2 (or Nextstrain clade 21K and 21L, respectively). At a global level, it is possible to say that the proportion of BA.2 has been increasing relative to BA.1 and in some countries it has been replacing it at high rates. In order to better assess the Omicron effectiveness on antibody escape, spread and infectious ability it is of the highest relevance to maintain a worldwide tight surveillance. Even though this variant has been associated with a lower death rate, it is important to highlight that the number of people becoming infected is concerning and that further unpredictable mutations may emerge as the number of infected people rises.

Endemic species may have complex histories: within-refugium phylogeography of an endangered Iberian vole.

Glacial refugia protected and promoted biodiversity during the Pleistocene, not only at a broader scale, but also for many endemics that contracted and expanded their ranges within refugial areas. Understanding the evolutionary history of refugial endemics is especially important in the case of endangered species to recognize the origins of their genetic structure and thus produce better informed conservation practices. The Iberian Peninsula is an important European glacial refugium, rich in endemics of conservation concern, including small mammals, such as the Cabrera vole (Microtus cabrerae). This near-threatened rodent is characterized by an unusual suite of genetic, life history and ecological traits, being restricted to isolated geographic nuclei in fast-disappearing Mediterranean subhumid herbaceous habitats. To reconstruct the evolutionary history of the Cabrera vole, we studied sequence variation at mitochondrial, autosomal and sex-linked loci, using invasive and noninvasive samples. Despite low overall mitochondrial and nuclear nucleotide diversities, we observed two main well-supported mitochondrial lineages, west and east. Phylogeographic modelling in the context of the Cabrera vole's detailed fossil record supports a demographic scenario of isolation of two populations during the Last Glacial Maximum from a single focus in the southern part of the Iberian Peninsula. In addition, our data suggest subsequent divergence within the east, and secondary contact and introgression of the expanding western population, during the late Holocene. This work emphasizes that refugial endemics may have a phylogeographic history as rich as that of more widespread species, and conservation of such endemics includes the preservation of that genetic legacy.

Prevalence of Leptospira antibodies in wild boars (Sus scrofa) from Northern Portugal: risk factor analysis.

Leptospirosis is a zoonosis of worldwide distribution, caused by infection with pathogenic spirochaetes of the genus Leptospira. The wild boar (Sus scrofa), an important hunting species in Europe, seems to play a significant role in the epidemiological cycle of leptospirosis. A total of 101 serum samples from wild boar hunted in Northern Portugal were analysed for leptospiral antibodies detection by microscopic agglutination test. Sera were collected during hunting seasons (2011-2013) and tested with 17 different pathogenic serovars of Leptospira. Antibodies against nine serovars were detected in 66 (65·4%) of these sera. Serovars Tarassovi and Altodouro exhibited the highest seroreactivity rates (23·8% and 16·8%, respectively), followed by Autumnalis (7·9%) and Bratislava (6·9%). Age and district of origin were found to be risk factors for the presence of leptospiral antibodies in contrast to gender. From a One Health perspective, this study revealed that wild boar should be considered as a potential source of leptospirosis dissemination for humans and animal species (domestic and wild) in shared environments, particularly in the Trás-os-Montes region.

LC: analysis of photodegradation kinetics of nitazoxanide in pharmaceutical formulations.

Nitazoxanide is a new broad-spectrum, antiparasitic drug agent. The photodegradation of nitazoxanide was studied in order to investigate the degradation kinetics of this drug. The analyses of the degraded samples were performed by a stability-indicating liquid chromatographic method. The degradation was carried out in acetonitrile with coated tablets or oral suspension powder in quartz cells under UVC light at 254 nm. The kinetics parameters, such as order of reaction, rate constants, half-life (t(1/2)), and the time when 90% of the drug original concentration was left, were determined. The photodegradation of nitazoxanide for both pharmaceutical formulations in acetonitrile solution shows a zero-order kinetics under the applied experimental conditions. The obtained results confirm the reliability of the chromatographic method for determining the kinetics run of nitazoxanide in the presence of its degradation products. The present study reveals the photolability of the drug in solution. Thus, appropriated photoprotection is recommended during the manipulation of the drug.

Comparative study of the efficacy and safety of loratadine syrup and terfenadine suspension in the treatment of chronic allergic skin diseases in a pediatric population.

The safety and efficacy of loratadine (Sch 29851, CAS 79794-75-5) syrup (5 or 10 mg QD) was compared to terfenadine (CAS 50679-08-8) suspension (30 mg b.i.d.) in a randomized, third party blind, parallel-group, multicenter trial. Two hundred thirty-six children ages 6-12 years, with chronic allergic skin disorders were treated for 14 days. The predominant skin condition was atrophic dermatitis (88% of the efficacy population). Evaluation of efficacy was based on investigator and patient assessment of symptoms, overall condition of the disease, and therapeutic response to treatment. After 7 and 14 days of treatment, and in the endpoint analysis (last valid study visit for all patients) the decreases from baseline in mean total sign/symptom scores, and all individual symptoms, did not differ significantly (p > 0.05) between treatments. Itching improved 54% in the loratadine group and 58% in the terfenadine group in the endpoint analysis. Forty-five percent of patients treated with loratadine and 46% of terfenadine-treated patients treated had complete or marked relief of their symptoms at endpoint. The efficacy of loratadine increased during the study, suggesting that patients did not develop tolerance to the medication over the 14-day course of therapy. Mild to moderate treatment-related adverse experiences were reported in 7/113 patients (6%) treated with loratadine and 11/119 patients (9%) treated with terfenadine. Single daily doses of 5 mg or 10 mg loratadine syrup were comparable to terfenadine suspension 30 mg twice daily for improving the symptoms of chronic allergic skin disorders in children. Loratadine was safe and well tolerated.

Reacoes a histoplasmina e paracoccidioidina na serra de Pereiro (Estado do Ceara - Brasil) / Histoplasmin and paracoccidioidin reactions in Serra de Pereiro (Ceara-State-Brazil)

Foram realizados 138 testes com histoplasmina e paracoccidioidina no municipio de Pereiro - Ceara, obtendo-se positividade de 6l,5 por cento e 32,1 por cento respectivamente, a estes antigenos. Os autores discutem a possibilidade da coexistencia da histoplasmose e paracoccidioidomicose-infeccao e/ou doenca na regiao

[Histoplasmin and paracoccidioidin reactions in Serra de Pereiro. (Ceara State--Brazil)]. / Reações à histoplasmina e paracoccidioidina na Serra de Pereiro (Estado do Ceará--Brasil).

Intradermal tests using histoplasmin and paracoccidioidin antigens were performed in 138 persons from Pereiro, Ceará, Brazil. The results were positive in 61.5% and 32.5% with histoplasmin and paracoccidioidin antigens respectively. These results suggest infection by H. capsulatum and P. brasiliensis in the people living in the studied area. New studies are necessary to detect histoplasmosis and paracoccidioidomycosis as clinical diseases in that region.