Saturday, 30th September 2023

How community, personal hygiene could contain Lassa fever spread, by experts

By Paul Adunwoke
23 April 2023   |   4:04 am
Despite, the efforts by the Nigeria Centre for Disease Control and Prevention (NCDC), and other relevant stakeholders in the health sector to prevent and eradicate Lassa fever cases in Nigeria, the virus is still so much around with us.

Despite, the efforts by the Nigeria Centre for Disease Control and Prevention (NCDC), and other relevant stakeholders in the health sector to prevent and eradicate Lassa fever cases in Nigeria, the virus is still so much around with us.  
In early this year 2023, many Nigerians lost their lives as a result of Lassa fever outbreak, including health workers and medical doctors.

The virus has been described as an animal-borne, or zoonotic, acute viral illness spread by the common African rat. It is endemic in parts of West Africa including Sierra Leone, Liberia, Guinea and Nigeria.    
Neighbouring countries are also at risk because the animal vector lives throughout the region. Lassa fever occurs more often in the dry season and before the onset of the rains, as peak season is between Novembers to March.
However, health experts advise that members of the public should embrace community and personal hygiene to prevent the spread of the virus across the country.
Consultant Public Health Physician at Lagos State University Teaching Hospital (LASUTH), Ikeja, Lagos, Dr. Oluwatoni Adeyemi, said prevention of Lassa fever relies on promoting good “community hygiene” to discourage rodents from entering homes. Effective measures include storing grain and other foodstuffs in rodent-proof containers, disposing of garbage far from the home, maintaining clean households and keeping cats.    
She noted that family members of affected persons should be careful to avoid contact with blood and body fluids while caring for them. Other preventive measures include avoid drying food in open places, avoid touching rat with bare hands and proper disposal of the carcasses of rodents.

Adeyemi explained that healthcare workers should always apply standard infection prevention and control precautions when caring for patients, regardless of their presumed diagnosis. These include basic hand hygiene, respiratory hygiene, and use of personal protective equipment to block splashes or other contact with infected materials, safe injection practices and safe burial practices.
She stated that healthcare workers caring for patients with suspected or confirmed case of Lassa fever should apply extra infection control measures to prevent contact with the patient’s blood and body fluids and contaminated surfaces or materials such as clothing and bedding. “When in close contact within 1 metre away with Lassa fever patients, healthcare workers should wear face protection, a face shield or a medical mask and goggles, a clean, non-sterile long-sleeved gown, and gloves sterile gloves for some procedures”.

Adeyemi noted that Laboratory workers are also at risk. Samples taken from humans and animals for investigation of Lassa virus infection should be handled by trained staff and processed in suitably equipped laboratories under maximum biological containment conditions. Healthcare workers seeing a patient suspected to have Lassa fever should immediately contact local and national experts for advice and to arrange for laboratory testing.
Adeyemi, however, noted that in terms of transmission, the reservoir, or host, of lassa virus is a rodent known as the “multimammate rat” mastomys natalensis. The agent is a single-stranded RNA virus belonging to the virus family arenaviridae. Once infected the rodent is able to excrete the virus in urine for an extended period of time.
She disclosed that humans usually become infected with Lassa virus from exposure to urine or faeces of infected mastomys rats. Lassa fever virus may also be spread between humans through direct contact with the blood, urine, faeces, or other bodily secretions of a person infected with Lassa fever. There is no epidemiological evidence supporting airborne spread between humans.
She noted that person-to-person transmission occurs in both community and healthcare settings, where the virus may be spread by contaminated medical equipment, such as re-used needles. Sexual transmission of lassa fever virus has also been reported.

She said: “Lassa fever occurs in all age groups and both sexes. Persons at greatest risk are those living in rural areas where mastomys are usually found, especially in communities with poor sanitation or crowded living conditions. Health workers are at risk when caring for Lassa fever patients in the absence of proper barrier nursing and infection prevention and control practices.”
Adememi said clinical signs and symptoms of Lassa fever incubation period ranges from 6 to 21 days. The onset of the virus, start when it is symptomatic, is usually gradual, with fever, general weakness, and malaise. 
She said: “After a few days, headache, sore throat, muscle pain, chest pain, nausea, vomiting, diarrhoea, cough, and abdominal pain may follow. In severe cases facial swelling, fluid in the lung cavity, bleeding from the mouth, nose, vagina or gastrointestinal tract and low blood pressure may develop. Protein may be noted in the urine. Shock, seizures, tremor, disorientation, and coma may be seen in the later stages. Deafness occurs in 25 per cent of patients who survive the virus. In half of these cases, hearing returns partially after one to three months”.    
“Transient hair loss and gait disturbance may occur during recovery. Death usually occurs within 14 days of onset in fatal cases. The virus is especially severe late in pregnancy, with maternal death or fetal loss occurring in more than 80 per cent of cases during the third trimester”.
She said lassa fever definitive diagnosis requires testing that is available only in reference laboratories. Laboratory specimens may be hazardous and must be handled with extreme care. Lassa fever virus infections can only be diagnosed definitively in the laboratory using the following tests, which include reverse transcriptase polymerase chain reaction (RT-PCR) assay, antibody enzyme-linked immunosorbent assay (ELISA), antigen detection tests, virus isolation by cell culture among others.
She noted that recommendations for lassa fever include active case search, contact tracing and daily reporting of Lassa fever cases starting from the communities.

She said: “Risk communication and social mobilisation is needed to keep raising awareness on Lassa fever. This should include a functional call centre, radio and television jingles information, education and communication materials on Lassa fever should also be widely distributed. Clinician sensitisation for early case detection and notification is needed”.
Abuja-based Public Health Physician and Health Promotion Specialist, Dr. Obinna Ebirim, said Lassa fever is caused by a virus called Lassa that is present in faeces, and urine of a special kind of rat. It is difficult for many to differentiate the rat types therefore people should just stay away from the urine and poo of rats. Infected persons can pass the infections to uninflected persons through contact with blood or body fluids while those working in hospital or laboratories can pick it from tools with this virus. As sexual transmission of lassa fever is possible.   
He noted that to prevent Lassa fever, people must keep rats away, keep foods or drinks away from rats, and protect themselves and others from being affected by the virus. To keep rats away, people must keep their environment clean and appropriately dispose their refuse and people must reignite community sanitation practices.  
He said to keep foods and drinks away from rats, foods must be stored on rodent-proof containers, food properly cooked before eating and water well boiled, avoid eating rat delicacies, and open spreading of grains where they are exposed to rodents. To protect people from those carrying the virus, we must avoid blood or body fluid contact with infected persons.    
Ebirim stated that laboratories must implement appropriate handling of Lassa samples while healthcare workers must apply infection prevention and control measures like hand washing, respiratory hygiene and use of personal protective equipment (PPEs). 

He explained that in terms of Lassa fever treatment there is an anti-viral drug called ribavirin, which is effective for treating virus, but it works better when given early. However, it is difficult to diagnose Lassa fever early in the course of the disease because it symptoms are seen in many other diseases but there are reference laboratories where a testing to make a definitive diagnosis can be carried out. 
Ebirim noted that government at all levels should continue to create awareness on Lassa fever, its prevention and what to do if you suspect Lassa fever. This must be done in a language and through a means that resonate with the diverse communities in Nigeria.   
“Also, through the good work the Nigeria Centre for Disease Control (NCDC) should continue case reporting, contact tracing and case management of Lassa fever”.  
He stated that the drug ribavirin for patients and tools that protect those who take care of the patients must be made available in our public health facilities. While government plays their roles, the individuals have roles to play in keep our environment clean and avoid eating rodents or rodent-infested foods. 
He said: “Lassa fever is real, it kills about 1 to 15 per cent of those infected, and there is no vaccines yet so prevention is our best bet”. 
Dr. Modupe Akinyinka, is Public Health Physician and Lecturer at the Lagos State University College of Medicine (LASUCOM), Ikeja, Lagos, said transmission of Lassa fever virus to humans occurs most commonly through ingestion or inhalation.  

She explained that mastomys rodents shed the virus in urine and droppings and direct contact with these materials, through touching soiled objects, eating contaminated food, or exposure to open cuts or sores, can lead to Lassa fever infection.
She said therefore people should avoid contact with mastomys rodents, especially in the geographic regions where outbreaks occur to prevent the virus. Putting foods away in rodent-proof containers and keeping the home clean help to discourage rodents from entering homes.     
She said: “People should avoid spreading foods out side to dry in the open place where the rats can access them”.
She noted that antiviral drugs such as ribavirin can be used in treatment of Lassa fever, especially when the treatment is given early in the course of the virus.
“People should avoid contact with blood and body fluids of infected persons”.  
Akinyinka said government should ensure people receive health education on how to prevent the virus and early detection to avoid spread. Also funding of healthcare to quickly identify and treat patients as well as research for possible vaccination.