ABSTRACT
There are four types of HTLV reported to date: HTLV-1, HTLV-2, HTLV-3, and HTLV-4. HTLV-1 and HTLV-2 are the most prevalent worldwide; they have a similar genome structure and share approximately 70% nucleotide sequence homology. HTLV-3 and HTLV-4 were identied recently in a few primate hunters in Cameroon [16,17]. Nucleotide identity between HTLV-3 and HTLV-4 is 63% [18]. Both HTLV-3 and HTLV-4 can be detected serologically by the commercial ELISA kits developed to detect HTLV-1/2, but they give indeterminate or inconclusive results on Western blotting [16-18].
