Hendra virus (HeV) causes highly lethal disease in horses and humans in the eastern Australian states of Queensland (QLD) and New South Wales (NSW), with multiple equine cases now reported on an annual basis. Infection and excretion dynamics in pteropid bats (flying-foxes), the recognised natural reservoir, are incompletely understood. We sought to identify key spatial and temporal factors associated with excretion in flying-foxes over a 2300 km latitudinal gradient from northern QLD to southern NSW which encompassed all known equine case locations. The aim was to strengthen knowledge of Hendra virus ecology in flying-foxes to improve spillover risk prediction and exposure risk mitigation strategies, and thus better protect horses and humans. Monthly pooled urine samples were collected from under roosting flying-foxes over a three-year period and screened for HeV RNA by quantitative RT-PCR. A generalised linear model was employed to investigate spatiotemporal associations with HeV detection in 13,968 samples from 27 roosts. There was a non-linear relationship between mean HeV excretion prevalence and five latitudinal regions, with excretion moderate in northern and central QLD, highest in southern QLD/northern NSW, moderate in central NSW, and negligible in southern NSW. Highest HeV positivity occurred where black or spectacled flying-foxes were present; nil or very low positivity rates occurred in exclusive grey-headed flying-fox roosts. Similarly, little red flying-foxes are evidently not a significant source of virus, as their periodic extreme increase in numbers at some roosts was not associated with any concurrent increase in HeV detection. There was a consistent, strong winter seasonality to excretion in the southern QLD/northern NSW and central NSW regions. This new information allows risk management strategies to be refined and targeted, mindful of the potential for spatial risk profiles to shift over time with changes in flying-fox species distribution.

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A bstraclA colony site occupied by grey-headed flying-foxes (Pteropus poliocephalus) from October to May on the central coast of N.S.W. was monitored over a 48 month period (1986)(1987)(1988)(1989)(1990). Faecal and spat-out material was collected for microscopic determination of contents. Comparison of food items in the droppings with the array of possible food sources present in the vicinity of the colony at the same time showed a marked preference for certain foods, in particular blossoms of the family Myrtaceae and of the genus Banksia. Cultivated orchard fruits were not a preferred food and were only taken at times when preferred food items were scarce.1035-3712/91/0100111$05.00 K. Parry-Jones and M. L. Augee Food Selection by Flying-foxes

Results from a long-term radio-tracking study of pteropodid fruit-bats are reported. Grey-headed fruit bats (Pteropus poliocephalus) captured from seven colonies in eastern New South Wales, Australia, were fitted with collar-mounted radio transmitters to permit their movements to be monitored over the following year. The sheepskin-lined leather collars were well tolerated by the bats over periods of 6-18 months. Bats moved between major colony sites for distances of up to 750 km, with movements occurring in both northerly and southerly directions. One bat from Lismore had a feeding range of 25 km, whereas in Sydney bats flew up to 17 km each night to feeding sites. There was considerable interchange between bats in adjacent colonies.

Previous authors have reported that Pteropus poliocephalus colony sites are occupied in response to blossom availability. However, in the present study it is reported that at the Gordon site in suburban Sydney, colony numbers were negatively correlated with the occurrence of pollen in the droppings. In addition, in contrast to reported occupational patterns at other colony sites, where flying-foxes are not present at the site during winter and early spring, the Gordon site was occupied by substantial numbers of flying-foxes throughout the entire period of 62 months from 1985 to 1990. As a result of the introduction of plants native to other parts of Australia and exotics from other continents, there is a variety of foods available throughout the year in the Sydney region, in comparison with less urbanized areas. This food supply permits the occupation of the Gordon colony site during winter and spring and reduces the migratory behaviour of flying-foxes throughout the year. It is concluded that in the absence of a restrictive food supply, the occupational pattern of the Gordon colony of P. poliocephalus is the result of the reproductive requirements of the species modified by the vagaries of blossom production in the native forests outside the foraging range of the colony.