Approximately one week after the first imported yellow fever case was reported in China, Beijing health officials reported two additional imported cases in citizens who traveled to Angola, according to a Chinese media report.

Public domain image/wikimedia commons
Public domain image/wikimedia commons

The cases from Fujian Province and Sichuan Province, both men aged 44 years, developed symptoms while in Angola and the virus was confirmed upon arrival back in Beijing.

Neither man was vaccinated against yellow fever prior to travel to Angola.

In addition, Shanghai health officials reported an imported yellow fever case Friday in a Jiangsu who traveled to Angola.

What is yellow fever?

According to the US Centers for Disease Control and Prevention, yellow fever virus is found in tropical and subtropical areas in South America and Africa. The virus is transmitted to people by the bite of an infected mosquito. Illness ranges in severity from a self-limited febrile illness to severe liver disease with bleeding.

Yellow fever disease is diagnosed based on symptoms, physical findings, laboratory testing, and travel history, including the possibility of exposure to infected mosquitoes. There is no specific treatment for yellow fever; care is based on symptoms. Steps to prevent yellow fever virus infection include using insect repellent, wearing protective clothing, and getting vaccinated.