No abstract

To date, there is no effective prophylactic agent to prevent COVID-19. However, the development of symptoms similar to covid19 could be prevented with an aqueous solution of chlorine dioxide (ClO2). This retrospective study evaluated the effectiveness of an aqueous solution of ClO2 (CDS) as a prophylactic agent in 1,163 family members living with positive/suspected COVID19 patients. Prophylactic treatment consisted of 0.0003% chlorine dioxide solution (CDS) orally for at least fourteen days. Family members in whom no reports of the development of covid19-like symptoms were found in the medical history were considered successful cases. The efficacy of CDS in preventing covid19-like symptoms was 90.4% (1,051 of 1,163 relatives did not report any symptoms). The comorbidities, sex and severity of the illness of the sick patient did not contribute to the development of symptoms similar to covid19 (P = 0.092, P = 0.351 and P = 0.574, respectively). However, older relatives were more likely to develop covid19-like symptoms (ORa = 4.22, P = 0.002). There was no evidence of alterations in blood parameters or in the QTc interval in relatives who consumed CDS. The recent findings regarding Chlorine Dioxide justify designing clinical trials to assess its efficacy for preventing SARS-CoV-2 infection.

The need for safe and effective antiviral treatments is pressing, particularly given the number of viral infections that are prevalent in animal and human populations, often causing devastating economic losses and mortality. In the context of the current coronavirus pandemic, which has highlighted how devastating the effects of a virus can be on a naive population, it is imperative to have rigorous and unbiased data on the efficacy and safety of potential antiviral treatments, particularly those that have demonstrated virucidal effects as a disinfectant, are being considered for use despite warnings on their potential toxicity, but no not have empirical evidence of their antiviral effect in vivo. Here, we tested the effect of chlorine dioxide (ClO2) on chick embryos infected with avian infectious bronchitis coronavirus (IBV). We determined virus-induced mortality on 10-day old embryos inoculated with 104 mean EID50/mL of attenuated Massachusetts and Connecticut IBV strains. We determined viral titres using RT-qPCR and conducted histopathological examination of various tissues and organs. Viral titres were 2.4-fold lower and mortality was reduced by half in infected embryos that were treated with ClO2. Infection led to developmental abnormalities regardless of treatment. Lesions typical of IBV infections were observed in all inoculated embryos, but severity tended to be lower in ClO2-treated embryos. We found no gross or microscopic evidence of toxicity caused by ClO2 at the doses used herein. Our study shows that ClO2 could be a safe and viable option for controlling avian coronavirus, and raises the possibility that similar effects could be observed in other organisms.

The number of strandings and unusual mortality events that involve marine mammals may have increased, and potential pathogens of the respiratory tract have been found during examination of individuals in many of these events. Given that the core microbiome is key to understand host-bacteria relationships and to identify their relevance for host health, we characterized the core respiratory microbiome of the Eastern North Pacific blue whale,Balaenoptera musculus, using blow samples collected by a small quadracopter drone. 16S rRNA gene high-throughput sequencing revealed 2,732 amplicon sequence variants (ASVs) of which 18 were shared by more than 50% of all blue whales and were considered as the core respiratory microbiome. Sixteen bacterial classes with a relative abundance higher than 0.02% were identified in the blow samples, and eight of these were also found in the seawater samples. Nonetheless, blow samples harboured classes not commonly found in seawater, such asAcidiomicrobia, Actinobacteria, Campylobacteria, Erysipelotrichia, Leptospirae, Mollicutes, andOxyphotobacteria. Only one whale presented a potential pathogen,Mycoplasma, associated with pulmonary pathology in mammals. Ours is the first study to characterize the respiratory microbiome of apparently healthy blue whales. The core microbiome identified here could be used as a baseline for future long-term studies on blue whale health.

No abstract