Several cases of influenza-like-illness (ILI) and/or conjunctivitis in humans have been linked to an outbreak of avian influenza in poultry at a smallholding near Corwen in northern Wales in the United Kingdom (UK). Three of the cases were hospitalized . H7N2, a low pathogenic strain of avian influenza (LPAI), has been identified as the cause of the poultry outbreak by the Department for Environment, Food and Rural Affairs (DEFRA) . Four human cases (two in Wales and two in north-west England) have confirmed Influenza A infection and are closely linked in time and place to the discovery of the H7N2 avian influenza virus. Since there are currently very low levels of seasonal influenza in the UK, it is presumed that they are infected with influenza H7N2. Antiviral medication was given to three of the cases and all have now recovered. The poultry infections have been traced back to a public market selling poultry in Chelford, north-west England, on 7 May.
In accordance with UK policy, it was decided to offer antivirals to anyone who may have been exposed to the diseased poultry or had close contact with cases. By 30 May, 20 avian flu contacts had been identified who have or have had symptoms of an ILI or conjunctivitis. The National Public Health Service (NPHS) for Wales is using the following definitions of cases and contacts:
- A case is an individual with influenza-like illness (fever above 38° C, aches and pains, cough/head cold, sore throat or conjunctivitis) who has been in contact with affected premises or to known infected poultry (handling/within one metre) or close contact with another human case;
- A contact is defined as an individual who has been in contact with affected premises or with known infected poultry (handling/within one metre) or has had close contact with another person with confirmed or presumptive avian influenza.
The NPHS of Wales identified 256 people who might have had contact with the avian flu: in household settings, in a school and in the workplace setting, including patients and staff at two hospitals. Seventy-nine patients and staff from Ward 6 at Ysbyty Glan Clwyd have been offered antiviral medication as a precaution because of contact with a healthcare worker who became sick with an ILI and is a part of the outbreak. Sixty-nine patients and staff from the Accident and Emergency Unit, Trysfan Ward and Gogarth Ward at Ysbyty Gwynedd are also being contacted because a patient, who is now discharged, is being treated for the avian flu virus .
As of 29 May, the NPHS had received microbiological test results from 12 patients in Wales. These were from swabs taken from the nose and throat and eyes. They were tested for the Influenza A viruses, including the H7 subtype that was isolated from the affected poultry. One test was positive for the H7 subtype and one for influenza A . Investigations are ongoing in the UK  and further results and updates will become available through the web-sites of the relevant authorities - the Health Protection Agency (www.hpa.org.uk), DEFRA (www.defra.gov.uk), the Welsh Assembly Government (www.wales.gov.uk) and the NPHS for Wales (www.nphs.wales.nhs.uk).
The authors would like to acknowledge the input from Roland Salmon (NPHS), Kathrin Thomas (NPHS) and Carol Joseph (HPA).