Epidemiological and virological investigations were carried out during an outbreak of Peste des petits ruminants (PPR) in Afghan (Bulkhi) sheep in Pakistan. The overall morbidity, mortality and case fatality rates were 41.0, 1.2 and 3.0%, respectively. The epidemic curve was plotted and the values for basic reproductive number (R0) and herd immunity threshold (HIT) for the affected flock were estimated to be 6.85 and 85.4%, respectively. The morbid material analysis by immuno-capture ELISA (Ic-ELISA) and haemagglutination assay (HA) revealed the presence of PPR virus. The PPR virus was isolated and identified through cytopathic effects, Ic-ELISA and transmission electron microscopy (TEM).

Key words: PPR, sheep, basic reproduction number, herd immunity threshold, epidemic curve.