Report type

Immediate notification

Date of start of the event

03/01/2013

Date of pre-confirmation of the event

07/01/2013

Report date

08/01/2013

Date submitted to OIE

09/01/2013

Reason for notification

First occurrence of a listed disease

Manifestation of disease

Clinical disease

Causal agent

Highly pathogenic avian influenza virus

Serotype

H7N3

Nature of diagnosis

Clinical, Laboratory (basic)

This event pertains to

a defined zone within the country

Summary of outbreaks

Total outbreaks: 2

Outbreak Location

• AGUASCALIENTES ( San Francisco de los Romo, San Francisco de los Romo Aguascalientes, Aguascalientes )

Total animals affected

Outbreak statistics

* Removed from the susceptible population through death, destruction and/or slaughter;

Source of the outbreak(s) or origin of infection

• Unknown or inconclusive

Epidemiological comments

The last outbreak of highly pathogenic avian influenza serotype H7N3 occurred in September 2012 in the northeastern part of the State of Jalisco. Following control and eradication measures, passive and active surveillance was strengthened and on 3 January 2013 SENASICA was informed of an increase in mortality and a decrease of egg production on a commercial layer farm in the State of Aguascalientes. Timely notification from the farmer and surveillance activities allowed immediate depopulation of the two affected production units, reason why both outbreaks identified are closed.
The first outbreak had a population of 146,755 birds aged 21-80 weeks, of which 2,990 sick and 740 dead. Clinical signs were conjunctivitis, edema, cyanosis and palpebral, comb and chin swelling as well as opisthotonos and sudden death. Additionally, during post-mortem inspections, hemorrhages were identified in trachea, lungs and tonsils. Control measures included vaccination of laying and breeding hens within the zone around the outbreaks and the buffer zone and the strengthening of biosecurity and control of poultry goods movements.
The second outbreak was detected during active surveillance conducted in the State of Aguascalientes and the virus was isolated in another commercial layer farm with a population of 138,000 birds over 81 weeks old, which was also depopulated. In both outbreaks, cleaning and disinfection of facilities and equipment as well as destruction of hen manure have been carried out. After depopulation, sentinel birds will be introduced in order to confirm the absence of infection and viral circulation.
Active and passive surveillance continues at national level. Epidemiological investigation is on-going.

Measures applied

• Stamping out
• Quarantine
• Movement control inside the country
• Screening
• Zoning
• Disinfection of infected premises/establishment(s)
• Vaccination prohibited
• No treatment of affected animals

Measures to be applied

• No other measures

Laboratory name and type

Biosecurity Laboratory Level 3, Mexico-United States Commission for the Prevention of Foot and Mouth Disease and Other Exotic Diseases of Animals ( National laboratory )

Tests and results

The event is continuing. Weekly follow-up reports will be submitted.