NAIROBI, May 17 (Xinhua) -- The UN World Health Organization (WHO) said on Friday that 30 countries in Africa with a total population of 508 million are considered to be at different levels of risk for yellow fever.
WHO Kenya Country Representative Dr Custodia Mandlhate told journalists in Nairobi that the global community should not be passive to this reality.
"Most of the estimated 200,000 yellow fever cases and deaths occurring annually are from African countries at risk," Mandlhate said during Kenya's launch of the Yellow Fever Risk Assessment Survey.
The field exercise runs from May 20 to June 2. "Kenya decided to carry the survey so as determine if there is circulation of the yellow fever virus," she said.
WHO said that the results will provide advice for implementation of the National Yellow Fever Control measures as well as help contribute to update the global WHO Yellow Fever Risk Map.
"Half of Kenya is currently classified by the WHO as high risk based on historical data and proximity to neighboring countries with recurrent outbreaks," the country representative said.
She noted that the most recent outbreak in the region occurred in South Sudan in 2003 and Uganda in 2011. WHO added that yellow fever was not reported from east Africa until the outbreak emerged in Kenya in 1992.
"Following the incident sentinel surveillance was established," she said. Mandlhate added that yellow fever is one of the acute infectious viral hemorrhagic diseases.
"If not detected and contained appropriately, it can cause explosive outbreaks particularly in high density areas which including urban centers," she said.
"It is therefore a disease of public health concern and can have a negative impact on the economy," the WHO official said.
Mandlhate said that despite yellow fever being preventable; it has re-emerged across the continent and some South American nations.
"At present, a high proportion of travelers visiting at risk areas are being immunized as required by the international health regulations," she said.
She added that WHO will continue to provide technical support to countries at risk, so that they can develop and monitor disease surveillance activities.
Ministry of Health Permanent Secretary Mark Bor said that the government, with the help of partners has concluded plans to conduct the risk assessment in 15 randomly selected points.
He added that the exercise will cost approximately 183,000 U.S. dollars.
"The assessment will involve conducting a zero-prevalence study in humans in order to determine the proportion of the population that has ever been infected with yellow fever," he said.
Bor added that the survey will also determine the presence of species, density, infectivity of yellow fever virus vectors in various ecological zones.
Ministry of Health Director of Public Health Shahnaz Sharif said that the public can also prevent infection by through wearing protective clothing or using bed nets and insect repellents.
"The survey results will also provide evidence based information that will assist the government to determine whether to include yellow fever vaccination into the routine immunization schedule," he said.
Sharif said that currently only two counties carry out routine immunization as they were affected in the last outbreak.
Ministry of Health Head of Division of Disease Surveillance and Response Dr Ian Njeru said that yellow fever is a viral infection with no specific treatment.
"Immunization is the primary means for preventing yellow fever while other measures taken are aimed at vector control," he said.
Njeru noted that approximately 85 percent of all cases involve the mild form while the rest can result in severe cases.
Kenya Tourism Board, Head of Finance Jonah Orumoi said that Kenya's classification as a risk area has had a negative impact on the tourism sector.
"It is therefore in our interest that the activity takes off and comes to a conclusion, so that Kenya like neighboring Tanzania is given a clean bill of health based on study finding," he said.
Orumoi noted that if Kenya is declared a no risk zone, citizens will not be required to have yellow fever vaccine whenever they travel abroad.