Abstract:
Yaba monkey tumour virus (YMTV) was first diagnosed in a colony of captive rhesus monkeys
(Macaca mulatta) in Yaba, Nigeria. It has been implicated as the cause of cutaneous nodules
in wild baboons (Papio species), rhesus monkeys (Macaca mulatta) and cynomolgus monkeys
(Macaca fascicularis). This article reports a case of cutaneous pox lesions caused by YMTV in
a free-ranging adult female vervet monkey (Chlorocebus pygerythrus) from the Umkomaas
coastal area in South Africa. The virus was identified by molecular sequencing from fragments
of the insulin metalloprotease-like protein and intracellular mature virion membrane protein
as well as the DNA polymerase genes. Phylogenetic analyses of these gene regions revealed a
99% similarity of the sample to YMTV. Although human disease caused by YMTV is normally
mild, it is recommended that persons in contact with non-human primates in the area of
Umkomaas who develop cutaneous lesions should inform their doctors of the possibility of
this infection. The extent and significance of the virus to human and non-human primates in
South Africa are not known. To the authors’ knowledge, this is the first diagnosis of YMTV in
South Africa and in vervet monkeys.
