The ambulance service has warned it is under severe pressure because of a rise in 999 calls from people who have flu symptoms.
South Central Ambulance Service has already missed key targets for response times because of a huge rise in Category A calls.
These calls, which relate to life-threatening incidents, are the most serious and require an ambulance to get to the scene in eight minutes.
But ambulance staff believe a worrying number of them are made by people who have flu rather than a more serious condition, putting a strain on the service. A rise in swine flu cases is being blamed.
The service has now cancelled staff training to help deal with the extra demand, and managers are being put into operational roles.
And people who call in with the lowest priority Category C calls are being referred to a clinical support desk to see if the person could be directed to alternative facilities instead of being sent an ambulance.
Neil Cook, head of operations at South Central Ambulance Service said: 'We have seen an incredible increase in our category A calls.
'The calls are primarily related to breathing difficulties and chest pains. We've seen this steadily rise since the end of August and it's aligned with swine flu or flu-like symptoms.
'The rise in these calls has put the service under incredible pressure.'
The problem comes because tightness in the chest and shortness of breath are classed as life-threatening signs but can also be symptoms of flu or swine flu.
Now ambulance service managers are asking people who experience these symptoms but also have the tell-tale signs of flu to think twice before dialling 999.
They say demand for ambulances is running 21 per cent above the daily norm for this time of year.
The number of Category A calls has risen the most – there are now 130 to 150 a day, a rise of 29 per cent since September. It means that while the service is used to responding to two to three category A calls in Portsmouth every hour, it is now called out to four or five.
Mr Cook said: 'The problem is when people ring up saying they have these symptoms we immediately start to treat it as a life threatening incident and we have to respond in eight minutes. So we have more calls which are demanding the quickest response times.
'We do not want to stop anyone with a real emergency from calling for an ambulance, but if you have symptoms such as tightness in the chest and shortness of breath, but also have flu symptoms, then we'd encourage you to ring your GP first or use other facilities rather than immediately ringing for an ambulance.'
WHEN TO DIAL 999... AND WHEN NOT TO
NHS says if you are struggling to breathe or have tightness in your chest, call an ambulance. If you also have flu symptoms go to the National Pandemic Flu Service at direct.gov.uk or call 0800 1 513 100 (textphone 0800 1 513 200).
People who have swine flu symptoms will be given a unique number and told where their nearest antiviral collection point is.
They should then ask a friend or relative who doesn't have swine flu to pick up their antivirals. The 'flu friend' must show their own ID as well as that of the patient.
If you have a fever or high temperature (more than 38C/100.4F) and two or more of the following symptoms, you may have swine flu:
- unusual tiredness
- runny nose
- sore throat
- shortness of breath or cough
- loss of appetite
- aching muscles
- diarrhoea or vomiting.
You should phone your doctor if:
- you have a serious underlying illness
- you are pregnant
- you have a sick child under one year old
- your condition suddenly gets much worse
- your condition is still getting worse after seven days (five for a child).
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