Abstract:
Poultry production in South Africa, a so-called developing country, may be seen as a gradient
between two extremes with highly integrated commercial enterprises with world-class
facilities on one hand and unimproved rural chickens kept by households and subsistence
farmers on the other. Although vaccination against Newcastle disease is widely applied to
control this devastating infection, epizootics continue to occur. Since the first official
diagnosis in 1945, through the sporadic outbreaks of the 1950s and early 1960s, to serious
epizootics caused by genotype VIII (late 1960s–2000), genotype VIIb (1993–1999), genotype
VIId (2003–2012) and most recently genotype VIIh (2013 to present), South Africa’s
encounters with exotic Newcastle disease follow global trends. Importation – probably
illegal – of infected poultry, poultry products or exotic birds and illegal swill dumping are
likely routes of entry. Once the commercial sector is affected, the disease spreads rapidly
within the region via transportation routes. Each outbreak genotype persisted for about a
decade and displaced its predecessor.
