PORTO-NOVO, Benin — In November 2014, an outbreak of Lassa Fever in Benin was quickly halted by the World Health Organization’s (WHO) Ebola Preparedness Team. The team of infectious disease experts from around the world had just arrived—coincidentally—when the outbreak occurred.
The team was there to prepare Benin for a possible outbreak of Ebola, given the spread of that disease in the region at the time. Dr. Youssouf Gamatié, WHO Representative in Benin, said “The measures the team introduced brought the Lassa fever outbreak quickly under control, and they would have been just as effective for an Ebola outbreak.”
The Ebola Preparedness Team had arrived just after four employees from St. John of God Hospital in Tanguiéta, Benin had died. The victims had symptoms causing suspicion of Ebola: all had a severe febrile illness and some had signs of a viral hemorrhagic fever.
But blood samples from all four of the people who died at the hospital were negative for Ebola. While this news was cause for celebration, a very important question remained: what did cause the deaths of these four hospital employees?
One member of the Preparedness Team, Dr. Catherine Smallwood, said that Lassa fever was strongly suspected next because nearby Nigeria had some cases of Lassa fever in 2014. Lassa fever belongs to the same family of diseases as Ebola.
They are both acute viral hemorrhagic illnesses and both are present in several West African countries. Every year, 100,000 to 300,000 people die of Lassa fever in West Africa.
Lassa fever is a zoonotic disease carried by a local rat, the “multimammate rat,” which sheds the virus in its urine and feces. Humans are infected with the fever when household items or food are contaminated by these excretions.
Human-to human infections and laboratory transmissions can occur in hospitals where proper infection prevention and control measures are lacking.
The detection of the disease can be very difficult due to variable courses that the disease can take. People can have slightly different symptoms. Only 15 percent of cases result in fatalities, but when a patient does die of Lassa fever, it occurs within 14 days. After ruling out Ebola, the victims were tested for Lassa fever. Two samples were positive.
When the disease is confirmed within a group of related people, isolation must be prompt, good infection and control practices along with tracing all contacts that patients have had with other people can stop outbreaks. The team began responding as they would to Ebola.
The Health Ministry joined in to enable the hospital staff to prepare an isolation unit, properly use the necessary personal protection equipment and monitor over 200 people who had been in contact with the four victims.
From here, the mystery of how Lassa fever spread was quickly solved. The team learned that a mother had died from Lassa fever two days after giving birth near Tanguiéta.
The baby became ill two weeks after being born and was treated at St. John of God Hospital by the hospital’s pediatrician—one of the 4 hospital employees who had died. The baby also died, and the disease spread from there.
When team members visited the baby’s household, they learned that the baby’s father, a well-known traditional healer, lost two of his three wives, including the baby’s mother, to Lassa fever. He believed it was a curse on his family.
The district medical examiner explained the disease to him. Pregnant women with Lassa fever have especially severe symptoms late in the third trimester. Maternal death and/or fetal loss occur in more than 80 percent of cases.
The healer agreed to follow the requirements to prevent the spread of Lassa fever. He also used the traditional method of lighting cinders all around the house to caution local people to stay away.
The medical examiner, who already had close connections to the community, initiated the work of educating locals on how to recognize Lassa fever and what to do if family members became ill.
WHO reports that, in Benin, there were only 16 Lassa fever cases, nine deaths and no new cases since November 2014. “The WHO-led mission to Benin highlighted the importance of preparedness and coordination at all levels—for a rapid, systematic and effective response,” says Dr. Gamatié.
Such a mission to halt these insidious diseases is proof of what preparation, coordination and cooperation of health officials and community members can accomplish. It encourages hopefulness in the quest to stop future epidemics of not only Lassa fever but also Ebola.