Detection of canine distemper virus (CDV) neutralising antibodies in small ruminants during peste-des-petits-ruminants virus (PPRV) surveillance in Zambia

TL;DR

This study found antibodies against canine distemper virus in small ruminants in Zambia, raising questions about cross-reactivity during PPRV surveillance.

Contribution

The study identifies CDV antibodies in small ruminants, highlighting possible cross-reactivity in PPRV antibody testing.

Findings

c-ELISA showed 6.44% PPRV seroprevalence on farms and 3.80% at markets.

Virus neutralisation assays found no PPRV antibodies but 45% CDV positivity in a subset.

The results suggest possible cross-reactivity between CDV and PPRV antibody tests.

Abstract

Canine distemper virus (CDV) is endemic in Zambia, while peste-des-petits-ruminants virus (PPRV) has not been detected. This study screened 962 farmed goats and 237 small ruminants at informal markets for PPRV antibodies using c-ELISA. A subset (n = 29) was re-analysed with virus neutralisation assays (VNA) for antibodies to PPRV and CDV due to cross-reactivity concerns. c-ELISA indicated 6.44% PPRV seroprevalence on farms and 3.80% at markets. While VNA detected no PPRV antibodies, 45% (13/29) tested positive for CDV, possibly suggesting cross-reactivity. Given the study’s limitations, further research is needed to determine whether PPRV is present in Zambia and assess potential cross-reactivity.

The online version contains supplementary material available at 10.1186/s12917-025-04732-w.

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