Lassa fever is a zoonotic disease caused by Lassa virus. Lassa virus is an RNA virus belonging to the arenavirus family and is widespread in West Africa. The disease is named after the village of Lassa in Nigeria, where it was first identified.
Characteristics and Symptoms of Lassa Fever
1. Transmission Routes
Rodents The disease is transmitted to humans mainly through a species of rodent (multi-mammalian mouse) called Mastomys natalensis. These rodents carry the virus and spread it into the environment through their feces, urine or saliva.
Human-to-Human Transmission: It can also be transmitted through direct contact with contaminated body fluids (blood, saliva, urine) or contact with contaminated objects.
2. Symptoms
Symptoms of Lassa fever can range from mild flu-like symptoms to severe hemorrhagic illness.
Early Symptoms:
Fever
Fatigue
Headache
Sore throat
Muscle aches
Chest pain
Nausea and vomiting
Advanced Symptoms:
Abdominal pain
Severe vomiting
Facial swelling
Fluid loss and electrolyte imbalances
Bleeding (from the mouth, nose, vagina or digestive tract)
Respiratory problems
Shock and neurological symptoms (restlessness, confusion, convulsions)
3. Incubation Period
The incubation period of Lassa fever usually ranges from 6-21 days.
Diagnosis and Treatment
1. Diagnosis
Laboratory Tests: Lassa fever is diagnosed by laboratory tests such as ELISA (Enzyme-Linked Immunosorbent Assay) tests, PCR (Polymerase Chain Reaction) and virus isolation to detect the virus in blood samples.
Clinical Evaluation: Symptoms and the patient’s travel history may also help in the diagnosis.
2. Treatment
Antiviral Drugs: Ribavirin may be effective if given early.
Supportive Treatment: Fluid and electrolyte balance, oxygen support, blood transfusions and infection control measures are important.
Prevention and Control
1. Rodent Control
Measures should be taken to prevent rodents from entering homes.
It is important to clean the areas around the houses where rodents can feed.
2. Hygiene and Protective Measures
Storing potentially contaminated food in closed containers.
Avoiding contact with infected people and using protective clothing to prevent human-to-human transmission.
3. Community Awareness
It is important to inform and raise awareness about Lassa fever.
Education about the symptoms and transmission routes should be provided.
Lassa fever is a manageable disease with prompt diagnosis and appropriate treatment. However, attention to hygiene and infection control measures in areas where it is prevalent is critical in preventing the spread of the disease.