By Mabinty M. Kamara
Since the Covid19 pandemic began, zoonotic diseases, especially those caused by viral pathogens with the ability to spread and infect a large number of people very quickly, have grabbed public attention like never before. One of these diseases is Lassa fever which is highly contagious and can be passed on from mother to child during pregnancy or through breastfeeding or other contacts between the mother and child. It has been around for over 40 years ravaging countries around the West Africa belt.
However, Lassa fever has been spreading to other African countries and by extension exported to the previously untouched Western World, hence, the growing concern and efforts to stop the spill-over.
But that notwithstanding, in Sierra Leone like in other West African countries like Nigeria, Guinea and Liberia, Lassa fever has, over the years, been killing dozens of people while a good number of others have miraculously survived its virulence. But the fact that it has over the years been ravaging some parts of the country, much attention is yet to be paid to addressing it, even as it continues to spread its tentacles across the country silently from the eastern Kenema district.
According to the United States Centre for Disease Control (CDC), between 100,000 and 300,000 infections of Lassa fever occur annually, with about 5,000 deaths. The Centre adds that some 10-16% of people admitted to hospitals annually in some areas of Sierra Leone and Liberia have Lassa fever.
The problem
Many factors could be attributed to the situation of Lassa fever in Sierra Leone and other parts of the world which continue to send a chill down the spine of many experts and those who are aware of the dangers of the disease. Lassa fever being predominant in countries with limited resources to put into the health sector, to curtail the community spread and treatments of infected persons through supportive care means that much has not been done in terms of concerted actions.
There is currently no vaccine, even on trial, for Lassa fever as there is no medication that has really proven to be effective, according to Emmanuel Saidu a lecturer at the Njala University who doubles as a Research scientist and a team lead for Highly Consequence Pathogens Projects funded by the US CDC. He said all that was being done for infected persons was supportive care and also treating symptoms until people naturally recover.
He added that the disease is caused by a genetically diverse pathogen which makes it difficult to understand, but that there are studies underway to investigate the pathogen in order to understand how it behaves, leading to an advice on vaccine production and also treatment regimen.
“They [Lassa fever virus] keep evolving overtime and are genetically unstable so they [researchers] are yet to know which vaccine formula will work for it,” Saidu said. Poverty, the lack of accurate health data and late diagnosis, traditional practices and low awareness, improper storage facilities for farmers and poor hygiene practices in homes and communities are major contributing factors.
Watta Koroma, a farmer in Kenema district, acknowledged improper care for produce after harvest. However, she blamed the situation on pesticides and the lack of proper storage facilities, noting that it also affects their yield. “Apart from the exposure to diseases, it also affects our reserves. Rat, particularly, is not a friend with rice but we don’t have a choice because they can access our makeshift stores,” she said.
According to Francis Suma, the Risk Communication Lead at the Kenema District Health Management Team, delay in care-seeking is also a major contributing factor to post treatment complications that may affect the sensory organs like the ears. Symptoms of Lassa fever according to health experts are similar to other common diseases like typhoid, malaria and other illnesses that have to do with high temperature. This sometimes leads to wrong diagnoses at an early stage, leading to fatalities. The lack of required logistics for health workers at the two referral hospitals is also a contributing factor that shouldn’t go unnoticed. Poor environmental management and practices have further exposed the human population to cohabit with endangered species.
How the spill-over occurs
Saidu noted that Lassa fever is contracted either through direct or indirect contact with the host which is dubbed Mastomys Natalensis and also known as “multimammate rat”. He noted that the disease can be contracted when the infected host comes into direct contact with food and drinks and leaves faecal materials like urine or droppings on it. A direct contact through consumption of the contaminated food materials can lead to infection.
He said Lassa fever can also be airborne when such faecal materials in dust particles are inhaled when sweeping around. “There are also studies that indicate that one can also come into contact with Lassa fever through semen. We also have a recent study that investigates that people can come in contact with Lassa fever in airborne ways. When you talk about Lassa fever in Sierra Leone, it is scary because a lot of people have been infected with Lassa fever. The recovery rate from hospitalisation is really, really low and it is endemic in the eastern part of the country,” he said, adding that Lassa fever is scary because it is also closely related to Ebola and the Marburg virus in terms of symptoms and fatality.
The scientist noted that it was a misconception that the rat with the elongated mouth or nose was the carrier of the virus. He said that it was a favourite rat which people like to hunt and eat from farm bush. He went on to say that people mostly got exposed to the disease during processing of the rat meat, especially when the human skin was broken, such as in an injury through which a virus can enter a person's body.
Coming to terms with the figures
In Sierra Leone, Lassa fever has over the years been predominant in the Eastern region particularly in Kenema district which makes it logical that the two referral hospitals; the Kenema government hospital and the Panguma hospital are both based in the east.
The selected chiefdoms are considered as the Lassa fever belt - Nongowa, Lower Bambara chiefdom, Small Bo chiefdoms and Dodo, Bo, and it also extends to Malegohun. However, Saidu noted that the disease is not limited to a particular region since rats do not have boundary limitations and can travel along with people from one place to the other.
Speaking to Politico, Francis Suma could not release current data on the disease case burden in the country but in 2020, between January and July alone, 8 Lassa fever deaths were recorded in three districts of which 5 were from Kenema in the east, 1 in Kono also in the eat, and 2 in Tonkolili in the north.
The Eastern part of Sierra Leone is highly forested which, according to experts, provides a perfect ecology for Multimammate animals like Mastomys natalensis which is the predominant reservoir for the Lassa fever virus.
However, Lahai Keifala, Research and Monitoring Superintendent at the Gola Rain Forest Conservation Limited which protects the Gola Rain Forest in eastern Sierra Leone, said that the forest currently houses 60 species of animals big and small, but that there is currently no specific data that estimates the abundance of Mastomys natalensis specie in the forest. Data obtained from a small mammal survey in 2008 indicates that there were seven of the mastomys natalensis specie found in the forest, 4 in the forest North, and 3 in the central part of the forest.
Moreover, he said that there had over the years been fewer or no cases of Lassa fever recorded in the forest edge communities though there had been cases in their operational chiefdoms.
Lahai Momoh, 60, who was born and lives in Panguma in the Lower Bambara chiefdom in Kenema District, survived Lassa fever along with about 10 of his close relatives – male and female as well as children. Four of them, including his father, succumbed to the virus. He explained how they were prevented from interacting with the bodies of their loved ones – much against their tradition – for fear of further transmissions.
How to stop the Spill-over
Lassa fever, like any other disease, can be prevented. Francis Suma said the disease is one of those under surveillance and that together with the district-based Lassa fever Control Programme supported by the United States Government and partners, they have been regularly monitoring the trend of incidence.
Suna Tucker, food, water, air, climate, livelihoods and Economic policy and security specialist at Stop Spillover – a USAID-funded global project that focuses on preventing spillover of viral pathogens like Lassa Fever, said that to stop the spillhover requires a one-health approach of all stakeholders in the Environment, Health and Agriculture and the community.
She emphasised behavioural change and community action, noting that families and farmers need proper food and produce preservation in order to prevent contamination. And for people to move away from cultural practices such as hunting and eating of rats generally.
Scientist Saidu also noted that studies were needed to give a head-up to know the abundance of Lassa fever rats in communities and how they can be controlled if they pose a threat.
Supportive care for hospitalised patients is strongly recommended by the W.H.O. The Risk Communication lead in the Kenema Government hospital noted that Lassa fever test was part of the testing procedure for any illness that has to do with high body temperatures, and some other likely symptoms. Such practices should be enforced and harmonised in all hospitals across the country for improved and timely diagnosis of the disease.
Community perception and behaviour change, improved sanitation and limiting interaction with the rats as food and co-habitation, early supportive care, prompt referral, rodent control–chemicals and traps to control rodent population can go a long way in salvaging the situation.
Heath centres should be supported with the required logistics for community interventions, treatment and diagnosis. Developed nations with the expertise and resources should also intervene and invest in vaccine candidate studies for the timely production of vaccines, as well as identify effective and reliable treatment mechanisms. Momoh, who survived the disease, said that one possible way of preventing cohabitation with rodents was the rearing of cats as pets in homes and communities since they are threats to rats, given that most people cannot afford pesticides.
The Deputy Director of Environmental Health Safety at the Environmental Protection Agency calls for people to deviate from practices that destroy the environment, saying that poor environmental management always has a reaping effects on humans. I am of the strong conviction that such collective actions can go a long way in addressing the Lassa fever menace that continues to wreak havoc on people.
Mabinty Magdalene Kamara is a Sierra Leonean journalist working with Politico Newspaper in Freetown.
This story was published with the support of Internews’ Earth Journalism Network. Alpha Abu, another Sierra Leonean journalist, contributed to this article.
Copyright © 2022 Politico (16/12/22)
