Study location
A desktop review was conducted to identify the most appropriate study
area on Java. Data of HPAI outbreaks between 2008 and 2014 and poultry
population statistics were gathered from the Participatory Disease
Surveillance and Response (PDSR) database in the Department of Animal
Health of the Indonesian Ministry of Agriculture (Azhar et al., 2010b;
Farnsworth et al., 2011). Based on HPAI disease reports, Purbalingga
District (Figure 1) was eventually selected because the PDSR data showed
evidence of historical outbreaks of HPAI H5N1; the presence of a range
of poultry production systems and species spanning all four Sectors,
based on livestock statistics data (Anon., 2019); a suitable level of
commitment from the local animal health authorities, plus personnel in
the livestock division who had received training in PDSR; and proximity
to the Disease Investigation Centre (DIC) laboratory at which sample
testing was performed. Purbalingga District is located in the Province
of Central Java, with an area of approximately 700 square kilometres and
elevation ranging between 25 and 2815 metres above sea level. It
consists of 18 sub-districts and 239 villages. The human population in
Purbalingga is 848,952 with varying density across the District. Based
on these demographic characteristics, Purbalingga was considered to be
representative of Java Island, both in terms of its demographics as well
as the range of poultry enterprise types and trade patterns.