The Department of Health and the Department of Agriculture, Forestry and Fisheries, supported by the South African Field Epidemiology and Training Programme (SAFELTP) and National Institute of Communicable Diseases (NICD) are working round the clock to contain the spread of the Rift Valley fever ahead of the 2010 Fifa World Cup.
Outbreak response teams dispatched to the affected four provinces, namely, Free State, Northern Cape, Eastern Cape and North West, continue in responding to the outbreak by tracking the mode of human infection and confirming new incidents, issuing daily updates, as well as intensifying public awareness to prevent the spread.
So far, the diagnosis of Rift Valley fever among human beings in South Africa as confirmed by NICD remains at 139 cases with nine mortalities since the first incident on 13 February 2010. Of the 139 laboratory confirmed human cases of Rift Valley fever, 93 cases including five deaths are from Free State, 36 cases including four deaths are from Northern Cape, eight cases from the Eastern Cape, one from North West and one whose history is still unknown.
The outbreak and surveillance response teams, supported by a technical expert from the World Health Organisation (WHO) Geneva have prioritised the following response measures:
* Laboratory, epidemiology and surveillance interventions (for diagnosis, case finding and investigation)
* Health promotion interventions
* Environmental health measures and
* Management of confirmed cases
Direct contact with Rift Valley fever infected livestock and or linked to farms with confirmed animal cases of Rift Valley fever, remain the main risk factor for the infection. The human cases are farmers, veterinarians and farm workers. Additional suspect cases are currently being tested. No human to human transmission of Rift Valley fever virus has ever been documented.
Affected farms are primarily clustered within Free State (initially in Lejweleputswa district, Bultfontein area). The Eastern Cape, Gauteng, Northern Cape and North West provinces have also reported Rift Valley fever among animals. The Department of Agriculture is vaccinating animals to contain the spread of the Rift Valley fever virus.
Rift Valley fever is a viral disease that can cause severe disease in a low proportion of infected humans. The virus is transmitted by mosquitoes and causes outbreaks of abortion and deaths of young livestock (sheep, goats and cattle). It is important to note that humans become infected from contact with infected tissues of livestock and less frequently from mosquito bites. The disease occurs throughout Africa and Madagascar when exceptionally heavy rains favour the breeding of the mosquito vectors.
Clinical features in humans:
Typically illness is asymptomatic or mild in the vast majority of infected persons, and severe disease would be expected to occur in less than one percent of infected persons.
Key symptoms:
* The incubation period (interval from infection to onset of symptoms) for Rift Valley fever varies from two to six days
* Sudden onset of flu-like fever and/or muscle pain
* Some patients develop neck stiffness, sensitivity to light, loss of appetite and vomiting; and
* Symptoms of Rift Valley fever usually last from four to seven days, after which time the immune response becomes detectable with the appearance of antibodies and the virus gradually disappears from the blood.
Severe form of Rift Valley fever in humans includes:
* Vision disturbances
* Intense headache, loss of memory, hallucinations, confusion, disorientation, vertigo, convulsions, lethargy and coma and
* Haemorrhagic fever.
People living in the affected areas are encouraged to seek medical attention at their nearest Health facilities, should they have any of the above symptoms.
Preventive measures:
While there is no specific treatment, the majority of persons affected will recover completely. People should avoid contact with the tissues of infected animals, refrain from drinking unpasteurised milk and prevent mosquito bites to avoid becoming infected. Farmers and veterinarians should wear protective clothing when handling sick animals or their tissues. There is no routine vaccine available for humans.
Media enquiries:
Charity Bhengu
Cell: 083 6797 424
Media interviews:
Frew Benson
Cell: 082 3724 199
Patrick Moonasar
Cell: 082 578 3107
Charles Mugero
Cell: 082 717 5306
Issued by: Department of Health
20 April 2010
