In general, evolution enables pathogens, whether viral or bacterial, to acquire resistance to antimicrobials. SARS-CoV-2 is no exception to this principle. Emerging variants, such as the Alpha (UK), Beta (South African) or Delta (Indian) variants, seem to be more transmissible or more resistant to antibodies generated by previous infection or by vaccination. In order to […]

Anosmia or loss of smell is a common symptom of COVID-19. The mechanism of this phenomenom is poorly understood but some studies suggest that the olfactory nerves may serve as a pathway for SARS-CoV-2 to enter the brain. Studies on the olfactory mucosa and human olfactory bulbs have not advanced very far, since it is […]

Innate, or non-specific, immunity is one of the organism’s first lines of defence against pathogens. NK (Natural Killer) cells are one element of this immunity. These cells are lymphocytes which, unlike B and T lymphocytes in adaptive immunity, do not need to have had previous contact with the pathogen in order to become rapidly active […]

In Qatar, the SARS-CoV-2 Alpha variant and then the Beta variant, were at the origin of two major epidemic waves at the beginning of 2021. It was later, in March, that the Delta variant was detected. It then spread throughout the country and was responsible for 43% of infections up to September. However, the vaccination […]

Despite the deployment of anti-COVID-19 vaccines in the 1st part of 2021, the number of cases and deaths linked to SARS-CoV-2 continued to increase in the northern hemisphere prior to the summer. The increase in cases was due in part to the emergence of the Delta (Indian) variant, which quickly became dominant at the expense […]

The Pfizer-BioNTech mRNA vaccine protects against infections, hospitalisations and severe cases of COVID-19. It reduces viral load and therefore reduces the infectiousness of the individual, thus hampering the virus’ spread. In Israel, SARS-CoV-2 had been largely eradicated between April and June 2021, but then the epidemic began to progress again. Israel, in common with other […]

After several months of calm since the beginning of 2021, Israel has now seen the arrival of a 4th wave of the COVID-19 pandemic. However, more than 55% of the population were vaccinated between 5 and 7 months ago with 2 doses of the Pfizer-BioNTech mRNA vaccine. This undoubtedly means that immunity will now be […]

At the end of 2019, China reported unusual cases of pneumonia in the province of Wuhan. A few weeks later, the first cases of COVID-19 were detected, the 21st of January in the United States and the 24th of January in France. But there was a great deal of uncertainty concerning the introduction of the […]

Although effective vaccines against COVID-19 are now on the market, there remains an urgent need to find drugs for the treatment of serious cases, since those currently available are limited. In addition, since other epidemics involving coronaviruses have occurred over the last twenty years (MERS-CoV, SARS-CoV-1), it is also important to develop active treatments against […]

Current vaccines, notably the Janssen vaccine, and the Moderna and Pfizer-BioNTech vaccines which use mRNA technology, are effective in the prevention of symptomatic COVID-19. These vaccines also reduce infection by the SARS-CoV-2 virus. In common with other countries, the United States began its vaccination campaign at the end of 2020. But over time, and because […]