“…The presenting symptoms are difficult to distinguish from a host of other febrile illnesses. After an incubation period of around 8 days (range 3-21 days), disease typically begins with the abrupt onset of fever, chills, headache, general malaise, anorexia, sore throat, and chest, back, muscle, and joint pains (Martini et al, 1968;Egbring et al, 1971;Martini, 1971;Stille D.G. Bausch et al / Antiviral Research 78 (2008) 150-161 153 and Bohle, 1971;Todorovitch et al, 1971;Gear et al, 1975;Pattyn et al, 1977;Anon., 1978;Smith et al, 1982;Nikiforov et al, 1994;Johnson et al, 1996;Bwaka et al, 1999;Bausch et al, 2006;Colebunders et al, 2007).…”