The onset of the disease, when it is symptomatic, is usually gradual, starting with
fever, general weakness, and malaise
. After a few days, headache, sore throat, muscle pain, chest pain, nausea, vomiting, diarrhoea, cough, and abdominal pain may follow.
What is Lassa fever causes and prevention?
Overview. Lassa fever is an
acute viral haemorrhagic illness caused by Lassa virus
, a member of the arenavirus family of viruses. Humans usually become infected with Lassa virus through exposure to food or household items contaminated with urine or faeces of infected Mastomys rats.
How did Lassa fever start?
Lassa fever (LF) is an acute and sometimes severe viral hemorrhagic illness endemic in West Africa. The disease was first recognized in Nigeria in 1969. Humans contract Lassa virus (LASV)
primarily through contact with contaminated excreta of the rodent Mastomys natalensis
, which is the natural reservoir.
Where is Lassa fever most common?
Lassa fever is an animal-borne, or zoonotic, acute viral illness. It is endemic in parts of
West Africa including Sierra Leone, Liberia, Guinea and Nigeria
.
Does Lassa fever cure?
Lassa fever is a rodent-borne zoonosis that clinically manifests as an acute hemorrhagic fever. It is
treated using ribavarin
. Surviving Lassa fever without receiving the antiviral drug ribavarin is rare. Only few cases have been documented to date.
Is Lassa fever a pandemic?
Like many potentially pandemic diseases, Lassa fever
is spread by a virus carried by animals
– in this case, rats – and in West Africa where it is endemic it can be as dangerous as Ebola or COVID-19.
How long can Lassa virus survive outside the body?
SURVIVAL OUTSIDE HOST: The virus is stable as an aerosol, particularly at low relative humidity (30 % RH). The biological half-live at both 24°C and 32°C ranges from
10.1 to 54.6 minutes
(20).
How is Lassa virus prevented?
Primary transmission of the Lassa virus from its host to humans can be prevented by
avoiding contact with Mastomys rodents
, especially in the geographic regions where outbreaks occur. Putting food away in rodent-proof containers and keeping the home clean help to discourage rodents from entering homes.
How does Lassa virus spread?
Transmission of Lassa virus to humans occurs most commonly through
ingestion or inhalation
. 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 infection.
Do all rats cause Lassa fever?
Lassa fever is a
viral infection carried by
the multimammate rat Mastomys natalensis (M. natalensis). This is one of the most common rodents in equatorial Africa, found across much of sub-Saharan Africa. Lassa fever mainly occurs in Sierra Leone, Liberia, Guinea, and Nigeria.
What are the symptoms of Lassa?
For the majority of Lassa fever virus infections (approximately 80%), symptoms are mild and are undiagnosed. Mild symptoms include
slight fever, general malaise and weakness, and headache
.
How is Lassa fever diagnosed?
Lassa fever is most often diagnosed by using
enzyme-linked immunosorbent serologic assays (ELISA)
, which detect IgM and IgG antibodies as well as Lassa antigen. Reverse transcription-polymerase chain reaction (RT-PCR) can be used in the early stage of disease.
What is the mortality rate of the Lassa virus?
Approximately 15%-20% of patients hospitalized for Lassa fever die from the illness. However,
only 1% of all Lassa virus infections result in death
. The death rates for women in the third trimester of pregnancy are particularly high.
Is Lassa fever a neglected tropical disease?
Lassa fever
remains a neglected tropical disease
, despite the virus being discovered more than 50 years ago in Nigeria. It is endemic in West Africa, but very little research has been conducted to date against this disease, for which there is no vaccine.
How long does Lassa fever last?
Lassa fever is an acute viral haemorrhagic illness of
2-21 days
duration that occurs in West Africa.
