At least eight people in Ghana's Savannah region died of suspected yellow fever infection based on interim laboratory results, according to the Ghana Health Service.

"The disease is presumed to be yellow fever, and samples have been shipped for final confirmation. Tests for other viral diseases including Ebola, Lassa, Marburg and Zika were all negative," Patrick Kuma-Aboagye, director-general of the Ghana Health Service, said in a statement on Friday.

He added that the affected people are nomads from selected communities in West and North Gonja districts of the region who have never been vaccinated against yellow fever.

The Ghana Health Service said those who have never been vaccinated against yellow fever should do so immediately. It further urged all people from the region who have fever, general weakness, headache, nausea and vomiting to immediately report to the nearest health facility.

"Avoid mosquito bites by wearing clothing that cover all parts of the body and report to the nearest health facility if you have fever and, especially when you have yellowish discoloration of your eyes," said the health agency.

Kuma-Aboagye said a team of experts from the Ghana Health Service, the Center for Disease Control Ghana, the World Health Organization Ghana and the Noguchi Memorial Institute for Medical Research has been deployed to support Savannah in investigations and instituting appropriate control measures.

Viral disease

Yellow fever is a viral disease spread through mosquito bites, which is common in some African and South American regions. Its symptoms include fever and jaundice at the early stages, and bleeding from the nose and mouth with bloody stools and vomiting of blood in later stages.

Death rates can be as high as 50 percent among those severely affected. Vaccination is a key preventive measure against the disease and one injection may protect an individual for 35 years, and possibly for life.

In collaboration with international bodies including the WHO and global vaccine alliance Gavi, the Ministry of Health and the Ghana Health Service launched a campaign in 2018 to vaccinate 5.3 million people against yellow fever in nine regions in Ghana.

Last year, the campaign focused on people aged between 10 and 60 and covered 139 districts at the highest risk of a yellow fever outbreak, as well as two districts with low vaccination rates.

Ghana's Health Ministry said it wants to attain a high population immunity against yellow fever for the people of Ghana as part of a road map to eliminate yellow fever in Africa by 2060.