Coronavirus cases increased by more than 16% in the last week in a further blow to hopes that restrictions might be eased in the next few weeks.

The biggest increases were recorded among school-age children, with around 25% more cases in all age groups from five to 20. Infections decreased in the over-85 population, indicating that vaccination is having a significant effect.

Admissions to hospital and intensive care were up by 8.6% and 14.2% respectively, while there was a 9% increase in the number of deaths recorded, from 204 to 223, the public health agency RIVM said in its latest weekly update.

Caretaker health minister Hugo de Jonge said the short-term future was ‘worrying and uncertain’ and gave the government ‘extremely limited’ scope to relax restrictions.

The health ministry has said the number of vaccinations will increase from 250,000 to 400,000 this week and 500,000 in the first week of April now that AstraZeneca has been cleared for use again and the Janssen vaccine is due to become available.

The percentage of tests returning a positive result increased for the first time in five weeks, going up from 7.6% to 8.1%. The reproductive number R also went up, from 1.06 to 1.11, calculated for March 8.

In total 46,005 people tested positive in the seven days to March 23, compared to 39,527 the week before, an increase of 16.4%. The total number of tests taken was 12% higher at 519,000.

In the last five weeks the infection rate among children under 13 has more than trebled from 70 per 100,000 to 245, while in the over-70 population the number has increased marginally from 122 to 127.

Among the 25 local health board regions the number of cases per 100,000 ranged from 167.8 in Twente to 410.8 in Zuid-Holland-Zuid.

The latest daily numbers continued the trend of the previous week, with another 5,636 cases reported in the 24 hours to 10am on Tuesday, a week-on-week increase of 15%.

There are currently 2,198 patients in hospital, five more than on Monday, while the number in intensive care fell by 15 to 623. Another 49 deaths were recorded, against a weekly average of 32.

Cases are continuing to decline in nursing homes, with 239 locations reporting at least one infection in the last two weeks, compared to 283 a week ago.