§ Mr. FlynnTo ask the Secretary of State for Northern Ireland, pursuant to his answer of 17 February,Official Report, column 408, if he will make a statement on the possible link between the recent outbreak and spread of Newcastle disease and the normal prohibition of the Newcastle disease vaccination. [17241]
§ Mr. Ancram[holding answer 24 February 1997]: Vaccination against Newcastle disease has been prohibited in Northern Ireland until recently because of the Province's status as a non-vaccinating area has effectively prohibited the importation of poultry—other than eggs and day-old chicks—from vaccinating countries. That has helped to prevent the introduction of Newcastle disease and other poultry diseases from which Northern Ireland has been free. Vaccination also makes it technically more difficult to detect and diagnose 723W Newcastle disease if it does occur. Moreover, Newcastle disease occurs even in countries which pursue a policy of vaccination. In such countries it is generally only the breeding flocks and laying flocks which are vaccinated; broiler flocks, which represent the majority of birds in any national flock are normally not vaccinated. The industry relies on maternal immunity to give a degree of protection. In such circumstances, broiler flocks are those most at risk and worldwide experience shows that a disease challenge can override the maternal immunity especially in the final two to three weeks of a broiler's life when the maternal immunity is waning. It is therefore very unlikely that a vaccination policy would have prevented the present outbreaks in broiler flocks which have occurred in Northern Ireland. Where vaccination, especially spray vaccination, is useful, however, is as a means of damping down the spread of Newcastle disease once it appears, and that is the policy which is currently being applied in Northern Ireland.