Interview with Dr Sylvie Briand, Director of the Epidemic and Pandemic Preparedness and Prevention department at the World Health Organization (WHO).
The rise of new variants, such as Omicron, appears linked to immune-deficient carriers. What is the relationship between the occurrence of these events and vaccination rates?
Sylvie Briand: Surely, unvaccinated, immune-deficient people who become infected with SARS-CoV-2 are like a culture dish for virus evolution. On the other hand, even though vaccines are very effective in preventing death and severe disease, they are not so good in preventing transmission, so people still get infected. When this occurs in immunosuppressed people, they can shed virus for a long time. Although this does not necessarily mean these people are contagious, it does offer the virus an opportunity to evolve.
The efficacy of vaccines against Omicron appears to be strongly reduced compared to previous variants. When will a tailored vaccine be ready for Omicron, and does it make sense to wait for it?
Sylvie Briand: We first need to remember the importance of having achieved the current vaccines. They were unprecedented in the speed at which they were developed and in the efficacy they have shown in avoiding death and severe disease. However, all vaccines were developed based on the initial SARS-CoV-2. Therefore, to increase the efficacy against new variants, developing new vaccines against other antigens is already a work in progress.
In addition, the WHO has set up an expert group on vaccines, the TAG-CO-VAC, against Covid-19 that will advise on possible vaccine composition (target antigen, sequence…) aiming to improve vaccine design, not only to extend the duration of the achieved immunity but also to develop vaccines which can stop or help reduce transmission.
There are reports on Flurona, a double infection with the flu and Covid-19. Is this an anomaly?
Sylvie Briand: Coinfections have been known for a long time, even before Covid-19. A report even found co-infection in more than 25% of children hospitalized for pneumonia. Therefore, it is possible to expect Covid-19 coinfection with other pathogens, like the influenza virus, particularly now that it is the high-season for this respiratory virus.
How can we be better prepared to confront the future challenges of this pandemic?
Sylvie Briand: At the WHO, we have tried to imagine three possible future scenarios, to help us better prepare for them. First, the virus might evolve towards becoming similar to the other four known coronaviruses circulating, which produce mild disease. Second, we can imagine a flu-like situation. Basically, there would be outbreaks at certain times of the year. Depending on population immunity, these outbreaks would be dangerous for at-risk groups, so excessive transmission should be avoided as well as serious health effects. The third scenario is a worst-case scenario, where we would get a completely new variant that is very transmissible and very virulent, and we would have to go back to square one. For all of these scenarios, there are interventions and plans that can be prepared ahead, and that’s what we are aiming for.
During this pandemic, and particularly in relation to the vaccines, we have seen the harmful effect of misinformation. What is infodemic management?
Sylvie Briand: In every pandemic, there is associated infodemic – information, including false or misleading messages, in digital and physical environments during a disease outbreak. However, for Covid-19, this has been particularly damaging due to social media. People are constantly bombarded with information. They can hardly judge its value and decide accordingly, as we have seen with respect to vaccination or the stigma that was placed on people of Asian origin at the beginning of the pandemic. Therefore, infodemic management is not only a risk communication, but goes a step further, to understanding the information needs of the population and satisfying them so that they can make appropriate decisions about their health.