Rift Valley fever: An emerging zoonotic threat to global health and agriculture

Table 2 Clinical signs of Rift Valley fever

Parameter	Mild form	Severe form
Onset	2-6 days after infection	Usually develops after initial mild symptoms
Symptoms	Fever, muscle and joint pain, headache, vomiting, photophobia	Ocular disease, meningoencephalitis, haemorrhagic fever
Prevalence	Majority of infected individuals	Occurs in a small percentage (< 2%) of cases
Ocular involvement	Rare	Seen in 0.5%-2% of cases; may cause blurred vision or blindness
Neurological involvement	Absent	Occurs in < 1% of cases; symptoms include seizures, confusion, and coma
Bleeding disorders	Not observed	Occurs in < 1% of cases; may include internal bleeding and multi-organ failure
Duration	4-7 days	Variable; prolonged and potentially life-threatening
Prognosis	Full recovery	May lead to permanent damage or death