Another syndrome manifests itself with acute neurological disease, meningo-encephalitis. The onset of this syndrome is also usually one to three weeks after the first symptoms appear. Death in patients with only meningoencephalitis is uncommon. RVF may also manifest itself as haemorrhagic fever. Patients with the RVF-haemorrhagic fever syndrome may remain viraemic for up to 10 days.
Most fatalities occur in patients who have developed haemorrhagic fever.
The antiviral drug ribavirin has been shown to inhibit viral growth in experimental systems, but has not been evaluated in the clinical setting. Most human cases of RVF are relatively mild and of short duration, so will not require any specific treatment. For the more severe cases, the mainstay of treatment is general supportive therapy. Prevention and Control RVF can be prevented by a sustained program of animal vaccination. Both live, attenuated, and killed vaccines have been developed for veterinary use.