Experts have called on the government to impose stricter rules on people who test positive for coronavirus when the lockdown rules are relaxed to prevent a second wave of infections.

The public health agency RIVM is aiming to test everybody with symptoms from June 1, the date when secondary schools are due to resume and public spaces such as cinemas and restaurants can take a new maximum of 30 people.

Anyone who tests positive will be asked to self-isolate for 14 days and keep their family doctor updated about their symptoms, but neither measure will be enforced.

Epidemiologist Arnold Bosman told Nieuwsuur the lack of obligation was a potential weakness in the system. ‘I don’t have any confidence that this will work well,’ he said. ‘Unless you stick to the severe measures of the lockdown, but that’s exactly what we are not doing.

‘Before March 12, suspected cases had to be reported to the regional health service [GGD]. But that duty to report is no longer in force. Now doctors have to take it upon themselves to confirm an infection.’

Bosman also said the arrangements to follow up on people who have been in contact with Covid-19 patients were inadequate. ‘It’s not a collective measure like the intelligent lockdown: it’s a question now of investigating individuals,’ he said. ‘You can’t reach people in the neighbourhood of an infected person with a letter. It’s not enough, and you can’t rely on it. What works is phoning them.’

Former doctor and chief public health inspector Wim Schellekens said he feared a second wave of infections if the rules were not tightened.

‘It will be worse than the first because we have a backlog of delayed healthcare,’ he said. ‘I’m not sure doctors and nurses can cope with it. They’re already on their last legs.’

Margreet de Graaf-Siegers, director of GGD Fryslân, who is co-ordinating source and contact research for the association of public health and safety, said a mandatory quarantine was not necessary.

‘We are relying on people’s sense of their own responsibility,’ she said. ‘Those who have been in contact with a person who tests positive will get a letter. That is what  the protocol says and we are keeping to that.’