Thursday, July 28, 2016

OIE Notification On Denmark LPAI H7N7 Outbreak

Credit DVFA



We've the OIE announcement on yesterday's report from  Denmark: Ducks Infected With LPAI H7 Avian Influenza that identifies the strain as LPAI H7N7 and confirms information provided by one of my readers (see yesterday's comments) that these ducks were being raised for release into the wild for hunting purposes.

First some excerpts from the OIE report, then I'll return with a bit more on H7N7.

Source of the outbreak(s) or origin of infection    

    Unknown or inconclusive

Epidemiological comments    

On 27 July 2016, LPAI H7N7 was detected in mallard ducklings collected in connection with the Danish surveillance programme for avian influenza. The diagnosis was confirmed and the virus was typed by sequencing. The killing of the mallards at the infected holding will be conducted on 28 July 2016. The Danish Veterinary and Food Administration has established a restricted zone of 1 km around the holding and are implementing the necessary measures in accordance with Council Directive 2005/94/EC

Control measures

Measures applied    

    Movement control inside the country
    Vaccination prohibited
    No treatment of affected animals

Measures to be applied   

    Disinfection / Disinfestation
    Stamping out

While a small number of human infections with (LPAI or HPAI) H7N7 viruses have been recorded, they have mostly been mild, often producing little more than conjunctivitis.

Last year, after an outbreak of LPAI H7N7 in the UK, the ECDC produced a Rapid Risk Assessment On LPAI H7N7, where they wrote:

Outbreaks in poultry holdings caused by low pathogenic or high pathogenic avian influenza A(H7N7) viruses have been reported previously in Europe, as well as human infections with low pathogenic avian influenza virus  A(H7N7). Such infections generally cause mild disease with influenza-like symptoms or conjunctivitis.

The group at risk for infection includes people with occupational exposure to poultry. This group should be made aware of the clinical features of infection, and advised to alert authorities and healthcare providers about  any relevant exposure if they develop influenza-like illness or other symptoms.

There is a low risk of zoonotic transmission to people who are directly exposed to infected birds during the culling and destruction process when there are outbreaks in poultry farms. The risk can be minimised if the exercise is performed under the safety measures recommended in Directive 2005/94/EC. Persons with direct contact to infected poultry before or during culling and disposal should be monitored for symptoms, and postexposure antiviral prophylaxis should be considered.

The risk for zoonotic transmission to the general public in EU/EEA countries is considered to be extremely low.

The caveat being (as always) that influenza viruses are constantly changing and evolving, and what we believe to be true about a particular subtype or strain can change over time.

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