NSW Arbovirus Surveillance Programme: Sentinel Flocks Linda Hueston Arbovirus & Emerging Diseases Unit CIDMLS - ICPMR

Surveillance Programmes Gather information about the occurrence of disease Gather information about the occurrence of disease Information gathered may allow prediction of outbreaks or epidemics or disease presentations Information gathered may allow prediction of outbreaks or epidemics or disease presentations “buy time” so we may be able to prevent an outbreak or reduce the number of cases “buy time” so we may be able to prevent an outbreak or reduce the number of cases

Surveillance is not Intervention It precedes intervention It precedes intervention Data collected may assist in determining Data collected may assist in determining - the type of intervention (health warnings, advice to people eg personal protective measures, vector control, vaccinations etc) the level of intervention (local areas, state or federal) the level of intervention (local areas, state or federal)

NSW Arbovirus Surveillance Programme Instituted by NSW Health in 1979 as a result of the outbreak in 1974 Instituted by NSW Health in 1979 as a result of the outbreak in 1974 Involved 3 states; NSW, Vic & SA Involved 3 states; NSW, Vic & SA - areas of previously large outbreaks with high morbidity & mortality & significant economic losses Function was to detect the presence of MVE and Kun as soon as possible to allow suitable, appropriate intervention. Function was to detect the presence of MVE and Kun as soon as possible to allow suitable, appropriate intervention.

NSW Arbovirus Surveillance Programme Involves Involves Monitoring sentinel flocks for virus activity Monitoring sentinel flocks for virus activity Monitoring mosquito populations & testing for presence of virus Monitoring mosquito populations & testing for presence of virus Monitoring human cases Monitoring human cases

Chicken Sentinel Programme How is it done? How is it done? - flocks of 12 wks old chooks are placed in “hotspots” and are bled weekly to look for the appearance of antibody What does it tell us? What does it tell us? - that the amount of virus present in an area has increased to a level that has allowed transmission.

The What and Where of Finding Virus Finding virus in mossies Finding virus in mossies - tells us only the virus is present but not how much is there Finding virus in sentinel chooks tells us the amount of virus present has increased to the point where it is transmitting to hosts Finding virus in sentinel chooks tells us the amount of virus present has increased to the point where it is transmitting to hosts Human transmission may be possible Human transmission may be possible

Chickens and MVE & Kun Chooks are “on the job” 24/7 Chooks are “on the job” 24/7 Each chook may receive 1000 bites/night Each chook may receive 1000 bites/night Over a week each chook may have “sampled” at least 7000 mossies → efficient & inexpensive system Over a week each chook may have “sampled” at least 7000 mossies → efficient & inexpensive system Has been shown that serocoversions in chooks preceeds human infection by 10 to 21 days → valuable time for health warnings & interventions Has been shown that serocoversions in chooks preceeds human infection by 10 to 21 days → valuable time for health warnings & interventions

Surveillance System Comments It’s a numbers game It’s a numbers game If mossie numbers are high and lots of mossies are infected they may trigger first If mossie numbers are high and lots of mossies are infected they may trigger first Mossie trapping represents one night only Mossie trapping represents one night only When mossie numbers are low chooks may be a better bet because they are bitten many times/night When mossie numbers are low chooks may be a better bet because they are bitten many times/night Chook testing represents 1000 bites per night per chook. There are 7 nights & 15 chooks → 105,000 chances that one or more birds could be infected Chook testing represents 1000 bites per night per chook. There are 7 nights & 15 chooks → 105,000 chances that one or more birds could be infected

Surveillance System Comments Examples of this numbers game Examples of this numbers game 1991 Griffith - mossie numbers were high and they triggered first notification of Kun; chooks seroconverted next bleed 1991 Griffith - mossie numbers were high and they triggered first notification of Kun; chooks seroconverted next bleed 1991 Hay - almost all the flock seroconverted to Kun but virus not isolated from mossies in Hay that season maybe numbers were down on the trapping night 1991 Hay - almost all the flock seroconverted to Kun but virus not isolated from mossies in Hay that season maybe numbers were down on the trapping night 2000/2001- large numbers of seroconversions to MVE & Kun through the flocks along Darling River no isolation of MVE virus at all in mossies but some isolates of Kun. But chook Kun seroconversions preceded the isolation of virus in mossies 2000/2001- large numbers of seroconversions to MVE & Kun through the flocks along Darling River no isolation of MVE virus at all in mossies but some isolates of Kun. But chook Kun seroconversions preceded the isolation of virus in mossies

Surveillance System Comments Examples of this numbers game Examples of this numbers game Isolates of RRV from mossies most years Isolates of RRV from mossies most years But human cases appear before the collection season starts But human cases appear before the collection season starts

Surveillance System Comments What does it all mean then? What does it all mean then? Means that surveillance is a complex system Means that surveillance is a complex system Relies on many different interactions Relies on many different interactions Some systems are better than others in some situations Some systems are better than others in some situations So keep options and minds open So keep options and minds open

Surveillance System Comments Never be free of arbovirus infections Never be free of arbovirus infections Can’t remove all the mossies Can’t remove all the mossies Can’t remove all the hosts Can’t remove all the hosts Vaccination (if available) won’t irradicate these diseases in humans because humans are not the only host (but it can reduce the number and severity of cases) Vaccination (if available) won’t irradicate these diseases in humans because humans are not the only host (but it can reduce the number and severity of cases)

Surveillance System Comments We can be vigilant and responsive We can be vigilant and responsive We can improve our surveillance methods to target organisms of interest - faster We can improve our surveillance methods to target organisms of interest - faster Remember time spent in reconnaissance is never wasted

NSW Arbovirus Surveillance Programme: Sentinel Flock Care Linda Hueston Arbovirus & Emerging Diseases Unit CIDMLS - ICPMR

Animal Ethics Project is overseen by the Animal Ethics Committee at Westmead Hospital Project is overseen by the Animal Ethics Committee at Westmead Hospital Subject to the Code of Practice for NSW Animal Research Programme Subject to the Code of Practice for NSW Animal Research Programme Approval is given only for 3 years after this time we must reapply Approval is given only for 3 years after this time we must reapply Approval is not guaranteed Approval is not guaranteed Project must be subjected to vet inspections and the supervising vet receives notification each week on the condition of each bird in each flock Project must be subjected to vet inspections and the supervising vet receives notification each week on the condition of each bird in each flock It is the only programme with ethics approval in the country It is the only programme with ethics approval in the country

Animal Ethics Every 3 years we must: Every 3 years we must: Demonstrate that the work we do is valid, humane, justifiable and considerate Demonstrate that the work we do is valid, humane, justifiable and considerate We must actively seek alternatives to animal use in research We must actively seek alternatives to animal use in research We must justify why animal use is essential for this project We must justify why animal use is essential for this project

Remember Choose the right breed of chook (must be layers not meat birds) Choose the right breed of chook (must be layers not meat birds) The birds health is paramount healthy birds make the best sentinels The birds health is paramount healthy birds make the best sentinels Birds naturally don’t like to be handled Birds naturally don’t like to be handled Take a little time to get the chooks accustomed to being handled and accustomed to you. Take a little time to get the chooks accustomed to being handled and accustomed to you.

All Chooks Require Adequate space Adequate space Adult birds should be provided with a minimum floor space of 0.4 square metres per bird. Overcrowding results in poorer performance and can lead to feather pecking, bullying, cannibalism and disease. Adult birds should be provided with a minimum floor space of 0.4 square metres per bird. Overcrowding results in poorer performance and can lead to feather pecking, bullying, cannibalism and disease.

All Chooks Require Adequate shade to ensure they are protected from heat radiating through roofing. A good balance of shade and light is required, bearing in mind that birds can do better with good light and that a very shady yard (and a too dark pen) may not dry out properly causing disease problems. Adequate shade to ensure they are protected from heat radiating through roofing. A good balance of shade and light is required, bearing in mind that birds can do better with good light and that a very shady yard (and a too dark pen) may not dry out properly causing disease problems. The enclosure should usually face towards the north. The enclosure should usually face towards the north. A dry area protected from the rain A dry area protected from the rain

All Chooks Require Protection from predators Protection from predators Good quality food. Good quality food. Feed must be balanced and appropriate to the age of the birds. Chick starter is fed to birds from 0 to 6-8 weeks, then grower feed up to weeks when the birds are put on layer mash or pellets. Commercially balanced rations are generally adequate and readily available, though layer rations should be supplemented with extra shell grit, at least in the peak laying period. During very hot periods a ration with extra protein can be fed to compensate for the birds not eating as much. Feed must be balanced and appropriate to the age of the birds. Chick starter is fed to birds from 0 to 6-8 weeks, then grower feed up to weeks when the birds are put on layer mash or pellets. Commercially balanced rations are generally adequate and readily available, though layer rations should be supplemented with extra shell grit, at least in the peak laying period. During very hot periods a ration with extra protein can be fed to compensate for the birds not eating as much.

Chook Care Housing – see the enclosed Dept of Ag booklet for diagrams of suitable housing enclosures Housing – see the enclosed Dept of Ag booklet for diagrams of suitable housing enclosures Position the enclosure so that the birds get morning sun but are protected from afternoon sun. Placement near shade trees or other structures which can given shade particularly on the west side will help with heat problem Position the enclosure so that the birds get morning sun but are protected from afternoon sun. Placement near shade trees or other structures which can given shade particularly on the west side will help with heat problem The size of the enclosure should provide half a square metre of floor space per bird at a minimum The size of the enclosure should provide half a square metre of floor space per bird at a minimum

All Chooks Require Adequate cool water Adequate cool water Protection from winds especially westerlies in winter. However a gentle breeze and a reasonably high roof should prevent ammonia building up which can cause respiratory disease. It also helps to dry the pen, keep the dust down and prevent other disease problems. Protection from winds especially westerlies in winter. However a gentle breeze and a reasonably high roof should prevent ammonia building up which can cause respiratory disease. It also helps to dry the pen, keep the dust down and prevent other disease problems. Regular inspection for their own health and the condition of their environment Regular inspection for their own health and the condition of their environment

Chook Care Housing Housing The coop should have adequate ventilation plus a draft free area for nesting. Having a chicken mesh front and a partly enclosed back portion with solid side walls is a good combination. To make the coop hygienic and easy to clean, the walls are best made from a non-porous material such as fibro sheeting, marine ply or metal. Avoid metal sheeting as it does not provide protection from the heat. The coop should have adequate ventilation plus a draft free area for nesting. Having a chicken mesh front and a partly enclosed back portion with solid side walls is a good combination. To make the coop hygienic and easy to clean, the walls are best made from a non-porous material such as fibro sheeting, marine ply or metal. Avoid metal sheeting as it does not provide protection from the heat.

Chook Care Housing Housing Ensure that the door is big enough to allow easy cleaning of the pen. Deep litter system is preferred. The floor should slope towards the door to allow drainage and to make the cleaning of the coop easy. The coop also needs to be predator proof (see DPI booklet) Ensure that the door is big enough to allow easy cleaning of the pen. Deep litter system is preferred. The floor should slope towards the door to allow drainage and to make the cleaning of the coop easy. The coop also needs to be predator proof (see DPI booklet)

Chook Care Housing Housing Allow at least 200mm of perch length per chicken. Make the perches from timber roughly 75mm x 50mm in dimensions and place them about 500mm from the floor. Allow at least 200mm of perch length per chicken. Make the perches from timber roughly 75mm x 50mm in dimensions and place them about 500mm from the floor. Provide nesting boxes. Mounted on the southernside of the enclosure about 600mm from the ground. Provide one nesting box per four to five hens. Nesting boxes should be about 300mm square. Provide nesting boxes. Mounted on the southernside of the enclosure about 600mm from the ground. Provide one nesting box per four to five hens. Nesting boxes should be about 300mm square.

Finally Blood collection & sample transport – see the demo Blood collection & sample transport – see the demo The chooks remain the property of the programme for the whole season and must be treated according to ethical guidelines for the use of animals in research The chooks remain the property of the programme for the whole season and must be treated according to ethical guidelines for the use of animals in research After the season the birds go to happy homes After the season the birds go to happy homes

Contacting Us You can contact the Arbovirus Lab by phone on (02) weekdays You can contact the Arbovirus Lab by phone on (02) weekdays You can contact me on the same number during the week or by You can contact me on the same number during the week or by