Two weeks ago, the Ministry of Health of Benin reported an outbreak of Lassa fever in Borgou Department, located in the north-eastern part of Benin. The outbreak involves a family of four (three
Beninese and one Togolese nationals) living in Kwara State, western Nigeria.

C. S. Goldsmith, P. Rollin, M. Bowen

The index patient was a 40-year-old woman in Kwara state in western Nigeria on the border with Benin who visited a local health center for symptomatic treatment of a nonfebrile illness on Feb 11.

Her condition deteriorated, causing abdominal pain and bleeding from multiple orifices. When she was transferred to the Borgou Department University Hospital Centre in Benin on Feb 17, she was confused and weak, vomiting blood, and bleeding abnormally from her uterus. She died on Feb 18, and blood specimens confirmed Lassa virus infection.

Blood flukes in Black and White

Between 11 to 24 February 2020, three relatives and contacts to the index case developed similar illness and were all transported from Nigeria and admitted to the CHUD in Benin. All the three case patients subsequently tested positive for Lassa fever. Since the beginning of the outbreak on 11 February 2020, four confirmed Lassa fever cases, including one death (case fatality ratio 25%) have been reported in Benin. All the cases were linked to Bukuro in Kwara State, Nigeria.

The three case-patients are currently receiving care in the Centre for Treatment of Viral Haemorrhagic Fevers (CTFHV) located in Parakou. A total of 34 contacts, including 23 health workers have been identified in Benin and Nigeria and are being followed up daily.

Several such events have occurred in the past (since 2014), usually at the peak of Lassa fever outbreaks in Nigeria, where the disease is endemic.