This summer’s music festival season could face last-minute cancellations due to staffing shortages caused by workers being told to self-isolate by the NHS Covid-19 app, according to industry leaders, who are calling for government support.

Paul Reed, chief executive of the Association of Independent Festivals, said this summer season, which is already greatly reduced after a number of high-profile cancellations including Glastonbury, could face further disruption.

Some festivals are struggling to put events on because of a lack of staff, including bar workers, security and logistics companies, according to Reed. “We’ve already heard anecdotally accounts of marquee companies isolating at home because their entire team’s being pinged so they can’t actually get to the site,” he said.

“I’ve heard of site managers getting pinged, and obviously that’s work that you can’t switch to doing remotely.”

Several festivals have been pulled already this summer, including the one-day Glastonbury event that was scheduled for September and the Boom Village event, which cited staffing issues as one of the reasons for cancellation.

Reed said the 16 August cutoff, when those who are notified by the app but have been fully vaccinated no longer need to self isolate, comes too late for this season’s festivals. “That will be too late for some members, but in any event, festivals are largely staffed by younger workers who will not be fully vaccinated by 16 August,” he added.

The reopening of hospitality venues on 19 July, including nightclubs and theatres, has contributed to a shortage of available workers for festivals, and Reed said some – for example, in rural locations – simply won’t be able to find replacement workers if staff are told to self isolate.

This weekend test festivals have taken place across the country that require no social distancing or mask wearing, including the 40,000-capacity Tramlines festival in Sheffield, Latitude, and Standon Calling. Reed said the true impact of staff being asked to self-isolate will be seen in the next few weeks as other major events begin.

Timm Cleasby, head of operations at Tramlines festival, said the event did face problems due to self-isolation but had contingency plans, including starting the site build two days early to allow for unexpected delays. But he called for the government to back an insurance scheme for festivals so that those that are hit by Covid-19-related problems have something to fall back on.

He said: “I’d say to the government, we’ve done everything asked of us for the last two summers. Please give us some certainty and get this thing done so we can properly get back to normal next year.”

Reed also highlighted a continued lack of a government-backed insurance scheme as one of the reasons that festival organisers who have gone ahead in 2021 are – in some cases – hugely financially exposed.

The culture secretary, Oliver Dowden, has said the government would only look at an insurance scheme once it was “possible for [events] to happen”, when lockdown restrictions have lifted. Reed and Cleasby are among a growing number of voices asking for that process to expedited in order that next year’s festivals can take place.

A spokesperson for the DCMS said: “We understand the challenges live events have in securing indemnity cover and are exploring what further support may be required.”