The JaSaD leader died at a Dhaka hospital on Friday morning, his family said
"The Queen is feeling well and is following her doctor's recommendations," it said.
She is almost asymptomatic, the Royal Palace added.
Mathilde, 49, who has been Queen of Belgium since 2013, has cancelled all her public events for the rest of this week.
COVID-19 hospitalisations in Belgium rose last month when the country removed almost all of its COVID restrictions. However, the number seems to be declining again.