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Swine flu virus: Updates and advice

Scientists at the Health Protection Agency have isolated a sample of the swine flu virus circulating in the UK and mapped its genetic fingerprint.
Brought to you by NHS Choices.

‘The pure sample of virus that we have isolated, together with its genetic fingerprint, will be important resources as scientific organisations join forces on the development of an effective vaccine,’ said Professor Maria Zambon, director of the HPA Centre for Infections.

There are now more than 50 confirmed cases of swine flu in the UK. All are responding to treatment and their symptoms are reported to be relatively mild.

The pandemic flu alert level from the World Health Organisation remains at Phase Five. Other recent developments include:

  • A warning from the Medicines and Healthcare products Regulatory Agency that counterfeit versions of antivirals such as Tamiflu may be being sold online.
  • Confirmed cases of the virus in South America, Asia and Africa as well as Mexico, North America and Europe.
  • The launch of a pre-recorded swine flu telephone information line on 0800 1513 513 (or 0044 207 928 1010 from overseas).
  • Ongoing delivery of a leaflet on swine flu to all UK households. This is also available in other languages and formats.
  • Plans announced to increase the UK stockpile of antivrials,antibiotics and facemasks as a precautionary measure.

How many cases of swine flu have been confirmed in the UK?

  • There are 55 people with confirmed swine flu in the UK. All have mild symptoms and are responding to treatment at home. The majority of cases are associated with travel to Mexico.
  • In addition to these confirmed cases, the HPA is investigating a number of suspected cases. The numbers will fluctuate daily as suspected cases are either confirmed or cleared.

Are any children or schools affected?

There are 27 confirmed cases of swine flu in children in the UK: 24 in London, two in Southwest England and one in Oxfordshire. As a precautionary measure, antiviral medication has been given to those who have been in close contact with the children and a number of schools have been temporarily closed to prevent the spread of the virus. 

What is the current state of alert? 

Countries with confirmed cases of swine flu

  • Mexico: 1626 (45 deaths)
  • US: 2254 (2 deaths)
  • Canada: 280 (1 death) 
  • Spain: 93
  • UK: 55
  • France: 12
  • Germany: 11 
  • Italy: 9
  • Costa Rica: 8 (1 death) 
  • Israel: 7
  • New Zealand: 7
  • Brazil: 6
  • Japan: 4
  • Republic of Korea: 3
  • Netherlands: 3
  • Panama: 3
  • El Salvador: 2  
  • Argentina: 1
  • Austria: 1
  • Australia: 1
  • Sweden: 1 
  • Denmark: 1  
  • Colombia: 1
  • Switzerland: 1
  • Hong Kong: 1 
  • Ireland: 1
  • Portugal: 1
  • Guatemala: 1
  • Poland: 1 


The swine flu alert level from the WHO remains at Phase Five, which means there is human-to-human spread of the virus in at least two countries in the same region. Phase Five is a strong signal that ‘a pandemic is imminent and that the time to finalise the organisation, communication, and implementation of planned mitigation measures is short,’ says the WHO. This is something that is already well under way in the UK.

As further information becomes available, WHO may decide to either revert to Phase Four or raise the level of alert to Phase Six, the highest level. The decision to move to Phase Five was based primarily on data demonstrating sustainable human-to-human transmission of the virus.

The WHO has defined six stages in the development of a pandemic. A virus outbreak is only classified as a pandemic at Phase Six.

If the WHO moved to Phase Six what would it mean?

If the WHO moved to Phase Six it would mean a global pandemic had officially been declared. However, the WHO alert levels reflect the global situation, and any action taken in the UK would be based on the situation here. This process would run as follows:

  • The Department of Health would assess the current situation in the UK before making any recommendations. 
  • Appropriate advice would then be given via NHS websites and other media.

What can I do to protect myself and my family?

Good hygiene is the key. You can reduce, but not eliminate, the risk of catching or spreading influenza by:

  • Using a tissue to cover your nose and mouth when coughing or sneezing.
  • Disposing of used tissues promptly and carefully.
  • Maintaining good basic hygiene, for example washing your hands frequently with soap and water to reduce the spread of the virus from your hands to your face, or to other people.
  • Cleaning hard surfaces (eg kitchen worktops, door handles) frequently using a normal cleaning product.

Phone your GP or NHS Direct if you develop the following symptoms within seven days of visiting Mexico or the United States OR you have had contact with a confirmed or probable case of swine flu:

  • Fever of 38°C or more.
  • History of fever AND flu-like illness (two or more of the following symptoms: cough, runny nose, limb/joint pain, headache).
  • Other severe/life-threatening illness suggestive of an infectious process.

You can check your symptoms using this symptom checker.

You can also prepare now and in the build-up to a possible pandemic by:

  • Confirming a network of ‘flu friends’ – friends and relatives who could help you if you fall ill. They could collect medicines and other supplies for you so you don’t have to leave home and possibly spread the virus. 

I have flu-like symptoms - what should I do?

  • Stay at home and rest.
  • Take medicines such as aspirin, ibuprofen or paracetamol to relieve the symptoms (following the instructions with the medicines). Children under 16 must not be given aspirin or ready-made flu remedies containing aspirin.
  • Drink plenty of fluids.
  • Phone your GP or NHS Direct if you have recently travelled to Mexico or the US or you have been in contact with someone who has confirmed or probable swine flu.
  • Phone your GP or NHS Direct if you develop complications such as shortness of breath.
  • Before you call, check your symptoms with this symptom checker.

Does the UK government have special drugs available?

The government has a stockpile of antiviral drugs (such as Tamiflu and Relenza) which should be sufficient to treat up to half of the population if they become ill – a reasonable worst-case scenario. The health secretary has said that the drugs have been shown to be effective if given in good time.

The government has also announced that additional antiviral medication has been ordered to increase UK supplies to 50 million doses, enough to treat 80% of the population.

How will I gain access to antivirals?

Arrangements are being put in place with local healthcare services for antivirals to be made available to those who need them.

People with symptoms and others at risk will be assessed by their GP. If antivirals are required, the GP will contact the local health protection unit, which is co-ordinating the distribution of antivirals.

If you have flu like symptoms and are concerned, stay at home. You can check your symptoms using the symptom checker. If you are still concerned, call your GP or NHS Direct. Do not travel out to your GP or hospital.

Do I need a face mask?

The widespread wearing of masks during a pandemic is unlikely to be effective in preventing people from becoming infected with the virus. However, they may have some limited ability to stop those already infected with the virus from spreading it.

There is no convincing scientific evidence that the widespread issue of face masks to healthy members of the public can stop this disease spreading. Moreover, they give can false reassurance, and can encourage people to ignore basic and straightforward hand hygiene measures that are known to be effective. 

However, specialist and other types of face masks are useful for frontline NHS staff who are caring for infected patients. The masks must be of the appropriate type, be worn correctly, changed frequently; removed properly; disposed of safely and used in combination with good hygiene measures.

Although there is a supply of face masks for NHS staff, more are needed. In the past week, contracts have been completed for the supply of more than 60 million masks. These will be both surgical and respiratory masks, which will give staff a broad range of protection when they come into contact with infected patients.

What is the latest advice about travelling abroad?

The Foreign Office has now advised against all but essential travel to Mexico. It also recommended that British nationals living in or visiting Mexico may wish to consider whether they should remain in Mexico at this time.

Travellers visiting affected areas should see a doctor immediately if they show signs of flu-like symptoms. The Mexican Secretariat of Health has advised people to avoid large crowds, shaking hands, kissing people as a greeting, or using the subway. Maintaining a distance of at least six feet from other people and frequent hand washing may also decrease the risk of exposure.

People returning from affected areas who become unwell within seven days of their return should stay at home and contact their GP or NHS Direct. They will be assessed and, if necessary, testing and treatment will be provided.

Are there travel restrictions in the UK?

No. However, people using public transport are being reminded to observe good hygiene. See Catch it, bin it, kill it.

Are there restrictions on public gatherings in the UK?

No. People are being advised to carry on with their daily lives as normal.

Is swine flu a mild infection and therefore no cause for concern?

  • We must not be complacent. It is too soon to assume it will be a mild infection. We don’t know the profile of the virus and we are closely monitoring each case that comes up.
  • Everyone who has contracted the virus in this country has been diagnosed early and treated with antivirals, which reduce the severity of symptoms.
  • Flu viruses change character very rapidly. They essentially evolve with the ‘fast forward’ button switched on. That means the flu virus is unstable. It can pick up and swap genetic material, which can dramatically change its character –  increasing the severity of symptoms. The virus could change in the autumn so we need to plan for all eventualities.

Why do people appear to develop less severe swine flu outside of Mexico?

This is not yet understood, and there could be a variety of explanations. It may be that people affected in Mexico may have sought treatment at a much later stage than those in other countries. General living and nutritional standards may also play a role. Other experts have suggested that there may even be a second separate virus circulating in Mexico which is having an impact but this is not known.

Where can I go for more information?

NHS Choices: swine flu

Health Protection Agency

World Health Organization

European Centre for Disease Prevention and Control


This article was originally published by NHS Choices.