Guidance

Investigation and management of possible human cases of avian influenza: amongst contacts associated with incidents (flowchart text description)

Updated 1 February 2024

Part 1: Case definition for possible human cases

Cases with one or more of the following listed symptoms:

• A: fever greater than 38°C (or history of fever)

• B: acute onset of at least one of the following respiratory symptoms: cough (with or without sputum), hoarseness, nasal discharge or congestion, shortness of breath, sore throat, wheezing, sneezing

• C: acute onset of conjunctivitis

• D: any other severe or life threatening illness suggestive of an infection process

Additionally, in the 10 days prior to symptom onset, the patient must have been exposed to a confirmed avian influenza incident in the UK.

This includes direct or close contact with infected birds (unwell or dead birds, or asymptomatic birds that became symptomatic within 48 hours following contact), their faecal matter or contaminated litter or other materials including eggs, and or parts of infected premises considered contaminated by animal health.

If the case definition is met, move to Part 2.

If the case definition is not met, move to Part 3.

Part 2: If the case definition is met

If met:

• notify and discuss with health protection team (HPT), if not already

• HPT to complete possible case report form accessed via PDU Sharepoint

• start treatment dose antivirals

• HPT discuss testing with local public health laboratory

• arrange for clinical assessment and specimens to be taken by an appropriate health professional, using recommended infection control measures (see below)

Move to Part 4.

Part 3: If the case definition is not met

Unlikely to be human case of avian influenza.

Treat and investigate as clinically indicated using standard infection control measures.

Part 4: Hospitalisation not warranted

The patient should be asked to isolate until laboratory results are available (isolation for asymptomatic contacts is not recommended routinely prior to laboratory results being available).

Move to Part 5.

Part 5: If patient deteriorates and requires hospitalisation

Move to Part 6.

Part 6: Hospitalisation warranted

Ensure ambulance and hospital aware of infection control advice (below).

Infection control measures are:

• staff PPE – correctly fitted FFP3 mask, gown, gloves and eye protection
• patient location – strict respiratory isolation, preferably in a negative pressure room
• patient – wear surgical facemask if tolerated (but not FFP3)
• HPT alert Colindale duty doctor

If ‘Influenza A positive but unsubtypeable or influenza A (H5) or (H7) positive’, move to Part 7 below.

If not, move to Part 8.

Part 7: Influenza A positive but unsubtypeable or influenza A (H5) or (H7) positive

Public health laboratories (PHL) duty microbiologist/virologist communicates result to local HPT, referring lab and respiratory virus unit. All presumptive results should be telephoned and confirmed in writing. Local HPT informs Acute Respiratory team Colindale (or Colindale duty doctor at any time if out of hours).

Part 8

If:

• influenza A negative
• influenza A positive subtyped as seasonal H3N2, H1N1pdm09
• influenza b positive

PHL duty microbiologist/virologist communicates result to local HPT, referring laboratory. Treat and investigate as clinically indicated.

Further information

Avian influenza guidance.

Local public health laboratories.