Patients at all London hospitals face long waits this week as hot weather, a high air pollution alert and planned industrial action puts extra pressure on emergency services.

The NHS has warned Londoners with pre-existing respiratory conditions to be aware that the Mayor has triggered a “high” air pollution alert. Imperial College London advised the Mayor to issue the alert due to high ozone levels, caused by the hot, sunny weather and south-easterly winds bringing pollutants from the continent towards the capital.

London also experienced “very high” pollen counts over the weekend and the first part of this week, triggering severe hay fever in sufferers.

Londoners are encouraged to keep on top of symptoms brought on by these conditions, including the use of antihistamines if affected by hay fever and the use of inhalers for those with asthma.

In addition to the above, junior doctors across London began their 72 hours strike at 7am today. The NHS is reprioritising resources to protect A&E and critical care but these services will be busier than usual.

A spokesperson for the NHS in London said:

“The NHS in London has been preparing extensively for this week’s strikes, but with industrial action, the hot weather and a high air pollution alert currently in place for the capital, our emergency services are already extremely busy.

“Current hot weather and high pollen counts coupled with the high level of air pollution means that there may be immediate health impacts for those with pre-existing conditions which affect their breathing – such as asthma.

“For this reason, it’s important that Londoners use our services wisely, using NHS 111 online as well as local services like general practice and pharmacies as first points of call for care, but people should always use 999 in a life-threatening emergency.

“And of course, we want people to enjoy the hot weather but enjoy it safely, by keeping hydrated, staying protected from the sun and keeping your home nice and cool. No one wants an avoidable trip to A&E.”