New COVID-19 Variant ‘Stratus’ Circulates as Cases Rise in the Netherlands
The Netherlands is experiencing a resurgence of COVID-19 cases, driven by a new subvariant known as Stratus, though health officials emphasize there is currently no cause for widespread alarm. While lockdowns and large-scale public health restrictions are a thing of the past, ongoing surveillance indicates a 21 percent increase in positive test results compared to the previous week.
Ongoing Surveillance and the Rise of Stratus
The National Institute for Public Health and the Environment (RIVM) continues to monitor the evolution of the virus through comprehensive germ surveillance. This involves analyzing positive COVID-19 tests from laboratories across the country and even examining sewage water to track circulating variants. Since the end of 2023, the Omikron variant and its subvariants have been dominant in the Netherlands. Cases dipped during the summer of 2025, but have begun to climb again in recent weeks.
The XFG subvariant, commonly referred to as Stratus, is now the most prevalent strain, and is also gaining traction in other nations. “It’s actually a bit early for a new variant, but it is there,” noted an immunologist at the Elisabeth-TweeSteden Hospital. The timing of this increase is slightly earlier than typically observed for seasonal upticks in respiratory illnesses.
How Variants Emerge and Spread
New variants arise through mutations – small changes in the virus’s genetic code. These mutations can allow a variant to replicate more efficiently, increasing its contagiousness. As one expert explained, “The new variant can cycle just a little faster than older variants and therefore ‘wins’.”
However, current data suggests the Stratus variant is not causing more severe illness. According to the RIVM, there are no indications that Stratus or other recent subvariants lead to more serious symptoms than previous Omikron strains. Symptoms are largely consistent with common colds – coughing and sniffling.
Immunity and Reduced Severity
Most individuals retain some level of immunity against the virus, and the immunologist suggests that newer variants appear to be less pathogenic. The risk of developing long COVID is also decreasing. A key factor in viral spread, as one expert pointed out, is the ability to infect individuals without causing severe illness. “Because then we just keep going to the supermarket and the pub, which means we infect each other more quickly.”
Despite the reassuring outlook, health officials urge caution, particularly for elderly individuals and those with underlying health conditions, who remain at higher risk of hospitalization. Vaccination remains a critical tool for protection. “For those who have received a call for a vaccine, my sincere advice is: do it,” the immunologist stated.
Existing Tests Remain Effective
Good news for those still holding onto at-home test kits: they still work. The immunologist explained that current tests target a corona protein that remains consistent across variants.
The first confirmed COVID-19 case in the Netherlands was detected five years ago, leading to widespread lockdowns, curfews, and public health regulations. Some habits adopted during that period persist, as highlighted in a recent video.
There is no reason to panic, but continued vigilance and responsible behavior are encouraged as the virus continues to evolve.
