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Advice for investigating people with possible swine flu

The Health Protection Agency has issued the following guidance on investigating individuals with possible swine influenza infection. You can also print off a pdf version attached.

1. Which patients should be tested?

Currently we do not have transmission of swine influenza A within the UK.

To be considered for testing a patient should have:

• Fever greater or equal to 38°C or history of fever, AND flu-like illness or other severe illness suggestive of an infective process


• Onset within seven days of travel from an area known to have cases of swine influenza. The updated list is available at on the HPA website.

2. Who do I contact for advice and access to testing service?

If the patient meets the criteria as a possible case of swine influenza, contact your local health protection unit (HPU).

The HPU will review case details with you and make an assessment as to whether the case needs testing for swine influenza A.

The HPU will advise you on the local arrangements for testing, the samples to take and transport of samples to the testing laboratory.

Usually you will be asked to take the test swab. The HPU will advise you on the recommended personal protective equipment (currently a surgical mask, gloves and a plastic apron).

3. Where should the patient be assessed?

Preferably at home. If at your surgery, then assessment should be undertaken away from communal areas. Please ensure all staff are aware of these arrangements.

Once assessed, if the patient is well enough to be at home then s/he should be advised to stay there.

Give advice about:

• Seeking help if clinical condition worsens.

• Avoiding contact with other people until results of tests known.

• Respiratory and hand hygiene.

• Cleaning hard surfaces regularly with a standard cleaning preparation.

If the patient needs hospital admission then please arrange this, ensuring the admitting team and any ambulance staff are informed of the potential diagnosis, as the patient must go into a side-room isolation.

4. Which specimens should I take?

Combined nose and throat swabs should be taken and placed into a bottle of viral transport medium, if possible duplicate samples should be taken:

•Use swabs with plastic shafts, as wooden swabs may affect the test.

• Combined nose and throat swabs must be taken and both placed into viral transport medium and sent to your local HPA/NHS laboratory. (See point 5).

• Please use the materials provided and do not use charcoal swabs or other bacteriological transport media.

5. How do I take the specimens?

Combined nose and throat swabs should be taken and placed into a bottle of viral transport medium, if possible duplicate samples should be taken:

The patient should wear a face mask (except while having samples taken). The staff member taking the swabs should wear a face mask, plastic apron and gloves.

The HPU will provide you with a pack where you will find:

• A request form

• Two bottles of viral transport medium (pink liquid)

• Two swabs

• Two sticky labels

• The packaging (sealable plastic bag, screw-top plastic canister, pre-labelled box) for the samples once taken.

Taking the swab

• Nasopharyngeal (NP) swab collection:

- Assemble all supplies including the virus isolation kit, gloves, pen, scissors, etc.

- If the viral transport medium (VTM) is frozen, allow it to thaw completely – usually takes 2-3 minutes when held in your hands.

- Tilt the patient's head back slightly. Bend the flexible wire of the sterile NP swab in a small arc and gently insert the swab along the medial part of the septum, until it reaches the posterior nares.

- Rotate the swab slightly several times to dislodge the columnar epithelial cells and then quickly remove the swab.

- Insert the NP swab into the VTM, cutting the excess wire or breaking the swab to fit inside the tube. Firmly secure the cap.

• Throat swab (TS) collection:

- Assemble all supplies, such as the virus isolation kit, gloves, pen, etc.

- If the VTM is frozen, allow it to thaw completely – this usually takes 2-3 minutes when held in your hands.

- Using the swab provided vigorously swab only the posterior pharyngeal walla.

- Insert the swab into the cold VTM, and break off the shaft so that it does not protrude above the rim of the container. Firmly secure the cap.

• Label both bottles with the sticky labels (name, address, date of birth).

• Check that the request form is completed including the contact details for receipt of the results (the HPU may have already done this for you).

• Place the two bottles of viral transport medium in the plastic bag and seal.

• Place the sealed bag in the plastic canister and screw shut.

• Place the request form and the canister in the cardboard box and close.

• Ensure the box is correctly labelled with the delivery address and contact numbers.

6. What should I do once I have taken specimens?

• Dispose of PPE as hazardous waste

• Wash hands thoroughly

• Call your local HPU to inform them that the sample has been taken and the precise location for collection by the courier company.

• The specimen should be given to the courier by the healthcare professional, not the patient.

• Specimens will be collected by the HPA courier and delivered to the nominated HPA laboratory.

7. Should I start the patient on antivirals?

If patient fulfils criteria for sampling then they should also start antivirals.

Standard adult doses: oseltamivir 75mg bd for five days (age 13 and over), zanamivir 10mg bd for five days. [Please check the British Neonatal Formulary for dose in children]

Please contact your local HPU for advice on the local arrangements for the supply of antivirals for the patient in the current situation.

8. Do I, or any of my staff, need antivirals?

You do not need to take antivirals ahead of the sample result. If the patient's samples prove positive for influenza A, then you will be assessed for antiviral prophylaxis by the HPU.

9. What should I do about the close contacts of the patient?

If the case meets the criteria for testing for swine influenza A, then you should advise the patient to inform their close contacts and for these individuals to be vigilant for flu-like symptoms.

The HPU will also take information about close contacts but further action will only be required if the index case samples prove positive for influenza A.

The laboratories will be performing the assays at least twice a day and the results will be notified to you.

aCotton swabs are not a suitable alternative but some chlamydia swabs are suitable and the manufacturers instructions should be consulted.

Health Protection Unit Contact numbers

London region
North East and North Central London 020 7759 2860
North West London 020 8327 7181
South West London 020 8812 7850
South East London 020 3049 4280
South East region
Hampshire and Isle of Wight 0845 055 2022/02380 777222
Kent 01622 710161/08702 385154
Surrey Sussex:
Leatherhead 01372 824262/08702 385156
Chichester 01243 770772/08702 385156
Lewes 01273 4030591/08702 385156
Thames Valley 0845 279 9879/ 08702 385155
East of England region
Bedfordshire and Hertfordshire 01462 705300
Essex 0845 1550069
Norfolk, Suffolk and Cambridge:
Norfolk 01842 767757
Suffolk 01473 329583
Cambridgeshire 01480 398607
East Midlands region
East Midlands North 01623 819000
Lincolnshire 01476 514699
East Midlands South 0116 263 1400
North East region
North East 0191 202 3888
North West region
Merseyside 0151 290 8360
Cheshire 0151 290 8360
Cumbria & Lancashire 01257 246450
Greater Manchester 01617 866710
South West region
Avon, Gloucestershire and Wiltshire 0117 900 2620
Gloucestershire 01453 829650
Wiltshire 01380 814000
Dorset 01202 851272
Somerset 01823 287817
South West Peninsula and Cornwall & Isles of Scilly 01726 627881
Devon 01803 861833/01726 627881
West Midlands region
Birmingham and Solihull 0121 255 0800
Coventry and Warwickshire 01926 478107
West Midlands North 01785 221126
West Midlands West 01562 756300
Yorkshire and Humber region
North Yorkshire 01904 567675
Humber 01482 672171
South Yorkshire 01142 428850
West Yorkshire 01132 840606

Standard practical advice for investigating individuals with possible swine flu infection

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