Topics on this page

Clinical diagnostic criteria
Testing
Treatment
Antiviral prescribing guidance
Clinicians' brief about the need for vaccination
Vaccine safety and monitoring - European Medicines Agency weekly pharmacoviligance report on vaccines and antivirals
Safety notice regarding the use of zanamivir (Relenza): updated 14 October 2009
Infection control guidance for health care settings
Clinical management
Pregnancy
Managing critically ill cases
Clinical management relating to oseltamivir resistant virus
Managing influenza-like illness in nursing and residential homes
Enhanced Surveillance of Guillain-Barré syndrome during the swine influenza pandemic

Clinical diagnostic criteria

Clinicians are now encouraged to diagnose pandemic (H1N1) 2009 influenza cases on the basis of symptoms.

The clinical diagnostic criteria are:

• Fever [pyrexia ≥38°C] or a history of fever,

AND

• influenza-like illness (TWO OR MORE of the following symptoms: cough; sore throat; rhinorrhoea; limb or joint pain; headache; vomiting or diarrhoea) OR
• severe and/or life-threatening illness suggestive of an infectious process

Testing

Testing should only be considered if patients are hospitalised, for the control of infection in hospitals, as part of 'spotter' surveillance schemes, or if there are unusual syndromes that are considered to have an infectious basis.

See the critical care section for use of serial testing.

Treatment

All those who have contracted pandemic (H1N1) 2009 influenza will continue to be offered antiviral drugs. However, it will remain a matter of clinical discretion as to whether antivirals should be prescribed in individual cases. It is vital that those in higher-risk groups get antivirals and start using them as soon as possible – within 48 hours of the onset of symptoms. This includes those with long-term lung, kidney, neurological, liver or heart disease; children under five; people over 65; those with diabetes mellitus; the immunosuppressed (whether caused by disease or treatment); patients who have had drug treatment for asthma within the past three years; and pregnant women.

Prescribing guidance for antiviral drugs from HPA and Department of Health

The HPA has produced detailed prescribing guidance for oseltamivir (Tamiflu) and zanamivir (Relenza). This includes advice on prescribing to infants, children, adults, patients with renal impairment or on renal replacement therapy and pregnant women.

This guidance is intended to enable health protection units (HPUs) to address local queries about the treatment and prophylaxis for pandemic (H1N1) 2009 influenza.  It is not a substitute for the Summary of Product Characteristics (SPC) and the Patient Information Leaflet (PIL) which must accompany the drug package provided.
Prescribing guidance for antiviral drugs (PDF, 257 KB)

Treatment and prophylaxis of immunocompromised patients is also discussed in detail in the section on clinical management relating to oseltamivir resistant virus.

The DH antiviral prophylaxis guidance for H1N1 sets out the circumstances in which it may be appropriate to offer a course of prophylactic antiviral medicine to patients with a serious underlying medical condition or who are pregnant during the H1N1 (swine flu) pandemic.

There is new guidance on the dosage regimen for children under 1 year of age and the authorisation of antiviral vouchers. Please see Guidance on the use of FP10SS forms and Antiviral Authorisation Vouchers during the H1N1 (swine flu) pandemic in England.

Clinicians' brief about the need for vaccination

The Clinical professionals brief on swine flu vaccination  provides information about swine flu vaccination, including at-risk populations, schedule, vaccine composition, and references, from Professor Sir Bruce Keogh, NHS Medical Director.

Vaccine safety and monitoring - European Medicines Agency weekly pharmacoviligance report on vaccines and antivirals

This weekly update provides an estimate of how many doses of centrally authorised pandemic vaccines and antivirals have been distributed or administered in Europe, a summary of the adverse reactions reported to the EMEA and other information on the benefits and risks of the vaccines and antivirals.
EMEA weekly pandemic pharmacovigilance report (link to EMEA site)

Safety notice regarding the use of zanamivir (Relenza): updated 14 October 2009

The Commission on Human Medicines issued the following statement on 14 October:

"The antiviral drug Relenza (zanamivir) should not be reformulated from its intended inhalation powder into a solution to be nebulised. This advice follows an incident outside the UK involving a patient who died when this unlicensed formulation caused a blockage in a mechanical ventilator. Further information is provided in the attached letter for healthcare professionals."

Letter from Chairman of the Commission on Human Medicines.  (pdf file on MHRA website)

Medical practitioners may contact us  for further advice should they need to consider any unlicensed or novel therapeutic treatments.

Infection control guidance for health care settings

The Department of Health has published Pandemic (H1N1 influenza: a summary of guidance for infection control in healthcare settings:

 DH swine flu summary of infection control for health care 

Key points from the guidelines are:

• Standard infection control precautions and droplet precautions must be used for patients with suspected or confirmed pandemic (H1N1) 2009 influenza.
• Good hand hygiene among staff and patients is an important control measure.
• Good respiratory hygiene is essential: ‘Catch it, bin it, kill it’
• The use of PPE should be proportionate to the risk of contact with respiratory secretions and other body fluids, and should depend on the type of work or procedure being undertaken.
• FFP3 respirators should be used during potentially infectious aerosol generating procedures.

Clinical management

This document serves as an update to provisional guidance for the clinical management of patients with influenza-like illness, severe influenza and complicationsprovided in 2007 by the British Infection Society, British Thoracic Society and HPA in collaboration with the Department of Health (pdf on DH website). Pandemic H1N1 2009 influenza: clinical management guidelines for adults and children

The British Thoracic Society has published revised Guidelines for the management of community acquired pneumonia in adults.  Clinicians are advised to consult this document for its potential relevance in treating patients with influenza.

Pregnancy

The Department of Health and the Royal College of Obstetricians and Gynaecologists has produced management guidelines for pregnancy: Pandemic H1N1 2009 influenza: clinical management guidelines for pregnancy

Health professionals may also refer to the  frequently asked questions on swine flu vaccination for pregnant women in the advice for public web pages.

Clinical management relating to oseltamivir resistant virus

This guidance outlines the principles and general management, guidelines for treatment and prophylaxis relating to immunocomprimised and immunocompetent patients relating to the development of oselatmivir resistant strains. First line treatment of immunocompromised patients should either be zaminivir or dual therapy with oseltamivir and zaminivir. Zaminivir is recommended for first line prophylaxis of immunocomprimised patients.Inpatient clinical management issues relating to oseltamivir resistant pandemic (H1N1) 2009 influenza virus (PDF, 156 KB)

This guidance outlines the risk assessment and management of cases and contacts with oseltamivir resistant pandemic H1N1 influenza.  It offers advice on infection control arrangements and use of antiviral drugs in treatment and prophylaxis. The associated investigation form is provided in rich text format (RTF).
Oseltamivir-resistant pandemic (H1N1) 2009 influenza case and cluster investigation (PDF, 178 KB)
Oseltamivir resistance case and cluster investigation form (Rich text format, 1.5 MB)

Managing critically ill cases

Since the first few cases of severe disease into intensive care units in the UK, the HPA has coordinated weekly international teleconferences between intensive care clinicians, and representatives from DH and WHO. By discussing the clinical reports of UK cases, we have been able to draw extensively on the experiences of colleagues in Mexico, Canada and the US, which has helped educate the UK’s response to the pandemic. In addition, the HPA supports teleconferences to the 54 European countries in the WHO European Region; this will give us the opportunity to not only continue building on our knowledge, but to share our growing expertise with other countries.

Using our increasing knowledge of managing cases of pandemic (H1N1) 2009 influenza, and the experiences of international clinicians, a clinical practice note on managing adult critically ill cases has been prepared by the HPA, Royal College of Anaesthetists, Intensive Care Society and College of Emergency Medicine.
Pandemic (H1N1) 2009 clinical practice note – Managing adult critically ill cases (PDF, 286 KB)

The Royal College of Paediatrics and Child Health with support from the HPA and the Department of Health has developed a clinical practice note to assist the management of paediatric cases of pandemic (H1N1) 2009 influenza. This has been approved by the Royal College of Anaesthetists, the Intensive Care Society, the Paediatric Intensive Care Society, the Association of Paediatric Anaesthetists Great Britain and Ireland.
Paediatric practice note for the management of critically ill children with pandemic (H1N1) 2009 Influenza (PDF, 121 KB)

Issues and recommendations relating to the use of serial testing of influenza in critical care settings are dicussed in the document.
Pandemic (H1N1) 2009 influenza testing in the critical care setting (PDF, 78 KB)

Influenza-like illness in nursing and residential homes

This guidance aims to provide advice on the generic management of cases or outbreaks of flu-like illness in nursing and residential homes and provides specific guidance appropriate to pandemic (H1N1) 2009 influenza.
Managing influenza-like illness (ILI) in nursing and residential homes during the current influenza pandemic (WHO Phase 6) (PDF, 91 KB)

• Enhanced surveillance of Guillain-Barré syndrome during the influenza pandemic
  An increased risk of Guillain-Barré syndrome (GBS) after influenza-like illness has been identified and it is essential that this risk is assessed during the current pandemic.
  Added/updated: 25 November 2009