WHO: monitoring results for Alpha, Beta, Gamma and Delta variants

The World Health Organization (WHO) released the results of its monitoring of the Alpha, Beta, Gamma and Delta variants of Covid-19.

The WHO Covid-19 “Weekly Epidemiological Update” of July 6, 2021 summarized the vaccine’s performance against the variants of concern, including for the Alpha, Beta, Gamma and Delta variants.

While current research indicates that protection is maintained against all Alpha variant outcomes, there may be reduced protection against “symptomatic disease” for the Beta and Delta variants.

However, protection against “severe disease” appears to be maintained for the Beta and Delta variants, although the available evidence remains limited.

On the other hand, there is “very limited” evidence regarding the overall efficacy of the Gamma variant vaccine.

Alpha, Beta, Gamma and Delta variants

On March 29, 2021, the WHO held global consultations in order to propose an integrated approach to monitor and evaluate the variants of interest of SARS-CoV-2 and to outline a decision-making process to inform policy recommendations, with a specific focus on the impact of COVID-19 vaccines.

It is normal for viruses to mutate. However, the more a virus spreads, the more opportunities it has to change.

Overall, the emergence of viral variants has sparked new calls for global collaboration to stop the spread of the virus universally, and requires ongoing monitoring and adaptation of the collective response.

Consequently, WHO, in collaboration with national authorities, institutions and researchers, routinely assesses whether SARS-CoV-2 variants alter the transmission or characteristics of the disease, or affect vaccines, therapeutics, and diagnosis. or the effectiveness of social and public health measures to control the spread of the disease.

The WHO publishes a Covid-19 “Weekly Epidemiological Update” that provides the most up-to-date information on the impact of Covid-19 virus variants on the effectiveness of different vaccines.

This is an area where the evidence remains preliminary, although it is developing rapidly.


Measures to reduce transmission continue to work against the new variants by reducing the amount of viral transmission and thus also reducing the chances of mutation of the virus.

These measures apply not only to the threats posed by epidemics and pandemics, but also to the ongoing threat of antimicrobial resistance.

Therefore, the importance of effective national infection prevention and control programs is a priority shared by the international community in addressing public health threats of international concern.

Also scaling up vaccine production and implementing vaccines as quickly and widely as possible are essential to protect people before they are exposed to the virus and from the risk of new variants.

Unequal access to vaccines and other health products and vaccine nationalism have contributed to the continued spread of the virus and the emergence of new variants, reducing the effectiveness of current tools and threatening progress everywhere.


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