Newcastle disease (ND) is caused by virulent strains of avian paramyxovirus type 1, also known as Newcastle disease virus (NDV). Despite vaccination, the frequency of reported outbreaks in Ethiopia has increased. From January to June 2022, an active outbreak investigation was conducted in six commercial chicken farms across areas of central Ethiopia to identify the circulating NDV strains. Thirty pooled tissue specimens were collected from chickens suspected of being infected with NDV. A questionnaire survey of farm owners and veterinarians was also carried out to collect information on the farms and the outbreak status. NDV was isolated using specific-pathogen-free (SPF)-embryonated chicken eggs and detected using haemagglutination and the reverse transcriptase–polymerase chain reaction (RT–PCR). The genotype and virulence of field NDV isolates were determined using phylogenetic analysis of fusion (F) protein gene sequences and the mean death time (MDT) test in SPF-embryonated chicken eggs. The questionnaire results revealed that ND caused morbidity (23.1%), mortality (16.3%), case fatality (70.8%), and significant economic losses. Eleven of thirty tissue specimens tested positive for NDV using haemagglutination and RT–PCR. The MDT testing and sequence analysis revealed the presence of virulent NDV classified as genotype VII of class II velogenic pathotype and distinct from locally used vaccine strains (genotype II). The amino acid sequences of the current virulent NDV fusion protein cleavage site motif revealed ¹¹²RRQKR↓F¹¹⁷, unlike the locally used avirulent vaccine strains (¹¹²GRQGR↓L¹¹⁷). The epidemiological data, MDT results, cleavage site sequence, and phylogenetic analysis all indicated that the present NDV isolates were virulent. The four NDV sequences were deposited in GenBank with accession numbers F gene (PP726912-15) and M gene (PP726916-19). The genetic difference between avirulent vaccine strains and circulating virulent NDV could explain the low level of protection provided by locally used vaccines. Further studies are needed to better understand the circulating NDV genotypes in different production systems.

An outbreak investigation of camelpox in dromedary camels (Camelus dromedarius) was conducted from October 2024 to May 2025 in Borena Zone, Ethiopia, with the aims of isolating, confirming the etiology and molecular characterization of camelpox virus from outbreak cases. The study integrated clinical assessment, virus isolation using Vero cell lines, and molecular characterization using conventional PCR, real-time PCR, sequencing and phylogenetic analysis. Clinically affected camels manifested typical pox-like lesions, fever and swollen lymph nodes, with a morbidity rate of 33.8% (24/71) and a case fatality rate of 4.2% (1/24). The virus was successfully isolated showing typical cytopathic effects of rounding of cells, syncytia, giant cell formation, aggregation and detachment. Conventional PCR targeting A-type inclusion protein (ATIP) gene amplified the expected 881 bp fragment with 26.3% positivity in both skin scab and nasal swab samples. Real-time PCR employing high-resolution melting curve analysis detected the viral DNA in 52.6% of samples with a melting temperature of 73.00 ± 0.20 °C for CMPV. Sequencing of the ATIP gene showed 100% nucleotide similarity with reference CMPV strains of CMPV M-96, CMPV CMS, strain 0408151v and CMPV genome (NC_003391), although a single nucleotide variation was noted when compared to the previously reported Ethiopian isolates (KU705085-KU705110) and Israeli isolates (MK910851 and MZ300856), and two nucleotide mismatches were observed with Sudanese isolates (KT931624 and KT931625). Phylogenetic analysis revealed that the current isolates clustered with CMPV strains of CMPV M-96, CMPV CMS, strain 0408151v and others but were distinct from previously reported Ethiopian isolates. This study provides significant insights on early diagnosis and control strategies.