mu variant covid/covid updates
This is the first in a series of explainers on vaccine development and dissemination. In WHO’s Vaccines Explained series, learn more about vaccines, from how they work to how they’re made to ensuring safety and equitable access.
All viruses evolve over time, including SARS-CoV-2, the virus that causes COVID-19. When a virus replicates or copies itself, it occasionally changes slightly, which is normal for a virus. Mutations are the term for these changes. A “variant” of the original virus is a virus that has one or more new mutations.
What causes a virus to evolve into a different strain?
The likelihood of a virus mutating increases when it is widely circulating in a population and causing many infections. The more opportunities a virus has to spread, the more it replicates – and the more changes it can go through.
The ability of most viruses to cause infections and disease is unaffected by most mutations. However, depending on where the changes occur in the virus’s genetic material, they may have an impact on the virus’s properties, such as transmission (it may spread more or less easily, for example) or severity (for example, it may cause more or less severe disease).
What effect do the new COVID-19 virus variants have on vaccines?
Because the COVID-19 vaccines that are currently in development or have been approved elicit a broad immune response involving a variety of antibodies and cells, they are expected to provide at least some protection against new virus variants. As a result, changes or mutations in the virus should not render vaccines useless. If any of these vaccines prove to be ineffective against one or more variants, the vaccines’ composition can be changed to protect against these variants.
On new COVID-19 virus variants, data is still being collected and analyzed. WHO is collaborating with researchers, health officials, and scientists to learn more about how these variants affect the virus’s behavior, as well as their potential impact on vaccine efficacy. For the most up-to-date information on the impact of COVID-19 virus variants on the effectiveness of different vaccines, go to WHO’s Disease Outbreak News. This is an area where the evidence is still developing and is still preliminary.
While we learn more, we must do everything we can to stop the virus from spreading so that mutations do not reduce the efficacy of existing vaccines.
Furthermore, vaccine manufacturers and programs that use the vaccines may need to adapt to the COVID-19 virus’s evolution: for example, vaccines may need to incorporate more than one strain during development, booster shots may be required, and other vaccine changes may be required. Trials must also be designed and maintained to allow for the assessment of any changes in efficacy, and they must be large enough and diverse enough to allow for clear interpretation of results. In order to understand the impact of vaccines, studies of their impact as they are deployed are also necessary.
What is WHO doing to track and understand the effect of virus variants on COVID-19 vaccine efficacy?
Since the beginning of the COVID-19 outbreak, WHO has been tracking mutations and variants. A dedicated Virus Evolution Working Group is part of our global SARS-CoV-2 laboratory network, and its goal is to detect new changes quickly and assess their potential impact.
COVID-19 virus genomic sequencing has been completed by research groups, and these sequences have been shared on public databases such as GISAID. Scientists can better track how the virus evolves thanks to this global collaboration. WHO recommends that all countries increase COVID-19 virus sequencing and share data to help each other monitor and respond to the pandemic as it evolves.
A SARS-CoV-2 Risk Monitoring and Evaluation Framework has also been established by the WHO to identify, monitor, and assess variants of concern. Surveillance, research on variants of concern, and evaluation of the impact on diagnostics, therapeutics, and vaccines will all be part of it. Manufacturers and countries will use the framework to determine what changes are needed for COVID-19 vaccines.
How can new COVID-19 virus variants be avoided in the future?
Stopping the spread at its source is still crucial. Current anti-virus measures, such as frequent hand washing, wearing a mask, physical separation, good ventilation, and avoiding crowded places or enclosed spaces, continue to work against new variants by reducing viral transmission and thus reducing the virus’s ability to mutate.
Scaling up vaccine production and distributing vaccines as quickly and widely as possible will be crucial in protecting people before they are exposed to the virus and new variants. To maximize global protection against new variants and minimize the risk of transmission, high-risk groups should be vaccinated first. Furthermore, ensuring equitable access to COVID-19 vaccines is more important than ever to combat the pandemic’s evolving nature. We expect virus circulation to decrease as more people get vaccinated, resulting in fewer mutations.
Why is it important to get vaccinated, even if new strains of the virus have emerged?
Vaccines are a critical tool in the fight against COVID-19, and using the tools we already have has clear public health and lifesaving benefits. We must not delay vaccination because of our concerns about new variants, and we must continue vaccination even if the vaccines are less effective against some COVID-19 virus variants. We must make use of the tools we already have while also working to improve them. Only if everyone is safe are we all safe.