Studies reported in english, that investigated lassa fever with reference to west africa were. Deadly lassafever outbreak tests nigerias revamped. Lassa fever is an acute viral illness that occurs in west africa. Of the total, 78 cases have been confirmed, amongst which 49 have died 63%. Preventing lassa fever infection in nigeria the guardian. Lassa mammarenavirus lasv is an arenavirus that causes lassa hemorrhagic fever, a type of viral hemorrhagic fever vhf, in humans and other primates.
Casepatient 4, a pregnant nurse, had a spontaneous abortion and died on day 9 of hospitalization. Brief history, diagnosing, and symptoms of lassa fever. Lassa fever was first documented in nigeria, in lassa village of borno state. Lassa fever, an acute viral haemorrhagic fever, extremely virulent and often infectious, occurs very frequently in different parts of nigeria 14 and affects approximately 100,000500,000 persons per year in west africa 5, 6. One wonders why borno state is usually home to a lot of things. Nigeria battles its largest lassa fever outbreak on record nigerias lassa fever outbreak has reached record highs with 317 laboratory confirmed cases, according to figures released by the nigeria centre for disease control ncdc this week. It has been known since the 1950s, but the virus was not identified until 1969, when two missionary nurses died from it in the town of lassa in nigeria. Pdf we report the epidemiology of lassa fever in bauchi state, a disease endemic region, in nigeria. Lassa fever, first identified in northeastern nigeria in 1969,1 is endemic in much of western africa. Pathophysiology and treatment of lassa fever springerlink. Nations development programme and the epidemiology of the disease, we estimate. It is endemic in west african countries, especially sierra leone, the republic of guinea, nigeria, and liberia, where the annual.
Lassa fever is endemic in west africa, where it probably kills several thousand. Department of community medicine, university of medical sciences. In nigeria, as of 17 may 2016, 8 states are currently reporting lassa fever cases suspected, probable, and confirmed, deaths andor following of contacts for the maximum 21day incubation period. Assessment of knowledge, attitudes and practices regarding. Found predominantly in west africa,1 it has the potential to cause tens of thousands of deaths. This is so called because at some point in the disease the patient bleeds. Prevent, detect, and control diseases of public health importance. The lassa virus is transmitted to humans mainly through food or household items contaminated by infected rats urine and faeces and by handling infected rats. A growing lassa fever outbreak in nigeria has killed 101 people, as west africa battles to contain a flareup of the virus, according to data from the nations health authorities released saturday. The world report by talha burki feb 24, p 7281 described an unprecedented astronomical rise in lassa fever cases in nigeria, for which the first case was reported in 1969 and the epidemiology and endemicity are well understood. The illness was discovered in lassa, borno state where it was first reported. Our knowledge of african arenavirus epidemiology has now been expanded by the isolation of viruses related to. Health workers may be infected by direct contact with blood, body fluids, urine, or stool of a patient with lassa fever. Mastomys natalensis, a rat that is common around human habitations in the region, is the host o.
Lassa fever is endemic in west africa and has been reported from sierra leone, guinea, liberia, and nigeria. In its severest form, if it is not treated, the disease can lead to death. Epidemiology and control of lassa fever springerlink. The last travelrelated case of lassa fever in europe was reported in the united kingdom in 2009.
Lassa fever is one of the hemorrhagic fever viruses like ebola virus, marburg virus, and others unlike ebola virus, lassa fever is not as contagious person to person, nor as deadly lassa virus is typically transmitted by the urine or feces of mastomys rats to humans. Many of those infected by the virus do not develop symptoms. According to the ncdc, 449 suspected cases of lassa fever have been reported across 17 states since january 1. While lassa fever is mild or has no observable symptoms in about 80% of people infected with the virus, the remaining 20% have a more severe multisystem disease.
The federal and state governments are responding to the outbreak by enhancing the disease surveillance for early detection, reinforcing treatment of patients, and conducting awareness campaigns among the affected population. Lassa fever is endemic in parts of west africa, particularly nigeria, sierra leone, liberia, and guinea. Some studies indicate that 300,000 to 500,000 cases of lassa fever and 5000 deaths occur yearly across west africa. Ribavirin, an antiviral drug, has been used to successfully treat patients with lassa fever. Lassa fever or lassa hemorrhagic fever lhf is an acute viral hemorrhagic fever caused by the lassa virus and first described in 1969 in the town of lassa, in borno state, nigeria. Lassa fever is a member of the arenaviridae virus family. Lassa fever outbreak hits nigeria infectioncontrol.
Since november 2015, at least 10 states in nigeria have been affected by an outbreak of lassa fever, an acute viral disease that causes fever, muscle pain, hemorrhage and sometimes death. Prospective study of the epidemiology and ecology of lassa fever. The natural reservoir of the lassa virus is multimammate rat species known as mastomys. It usually causes mild symptoms, including slight fever, weakness, and headache. Adekunle olatayo adeoti1, onyekachi ojiaku2 and louise sigfrid3 1department of medicine, ekiti state university teaching hospital, ado ekiti, nigeria 2department of medicine, ekiti state university teaching hospital, ado ekiti, nigeria 3clinical research fellow and public health specialist, university of oxford, united kingdom. Coordinate surveillance systems to collect, analyse and interpret.
Isaac adewole, recently confirmed reported cases of lassa fever infection in niger, nasarawa, plateau,taraba, rivers, edo, delta, kogi. Promed reported on february 2016 that nigeria has recorded 176 cases with 108 deaths a case fatality rate of 61 percent. Even after recovery, the virus remains in body fluids, including semen. An infected person can spread lassa to others via their blood, urine and other bodily fluids. Lassa fever can cause a potentially fatal illness, is highly contagious, and can rapidly spread. Development of a therapeutic for lassa fever national. Outbreaks of lassa fever occur regularly in west africa, where the virus is carried by rats. Symptoms include fever and damage to multiple organs and the circulatory system. Rapid increase in lassa fever cases nigeria reliefweb. A 2012 outbreak of lassa fever in nigeria caused more than 1,700 people to become infected, but 112 deaths, according to the nigerian center. In studies of lassa fever in sierra leone, the prevalence. The risk of getting lassa fever in the united states is extremely low signs and symptoms of lassa fever are usually mild lassa fever can be treated if a healthcare worker suspects lassa fever in a patient, a laboratory test can diagnose the disease. The history of recognized human arenavirus infection in africa began in 1969 with the mysterious death of two medical missionaries and the nearfatal illness of a third frame et al.
However, some lassa fever cases have been imported into the u. Data are based on the gideon database which relies on standard text book. Lassa fever accounts for an estimated 200,000 to 500,000 cases and 5000 deaths yearly in west africa, particularly in sierra leone, nigeria, liberia and r epublic of guinea. It is spread through contact with infected rodents or their droppings, or through close contact with a person who is sick with lassa fever. Global status is one in a series of gideon ebooks which summarize the status of individual infectious diseases, in every country of the world. Lassa fever by stephen berger, md overdrive rakuten. Lassa fever is a viral haemorrhagic fever transmitted by rats. Pdf baseline mapping of lassa fever virology, epidemiology and. Containing current lassa fever outbreaks in nigeria the. Lassa fever is endemic exclusively in west africa figure 4. Cases have also been reported in ghana, benin, togo, burkina faso. Lassa fever is spread through direct contact with the. Lassa fever in nigeria watch level 1, practice usual.
Lassa fever is caused by a singlestranded rna virus that is animal borne zoonotic. An acute viral infection found in the tropics, especially in west africa. Lesson learned from the investigation and response of lassa fever. Lassa fever action committee in view of the outbreak of lassa fever recorded in the country local media 18012016. Lassa mammarenavirus is an emerging virus and a select agent, requiring biosafety level 4equivalent containment. Although endemic to the west african nation, lassa fever has never reached this case count in nigeria before. The reservoir, or host, of the lassa virus is a rodent known as the multimammate rat. Expenditures for lassa fever research have reflected this perspective and have concentrated on detection, vaccine development and treatment rather than prevention and control in. Lassa fever epidemiology in nigeria implications for research pdf. Nigeria battles its largest lassa fever outbreak on record. Lassa fever death rates in nigeria higher than expected cnn. The reservoir of the lassa virus is a rodent of the genus mastomys known as multimammate rat.
Lassa fever, also known as lassa hemorrhagic fever lhf, is a type of viral hemorrhagic fever caused by the lassa virus. Such infections are often asymptomatic, but in those who become ill, the disease can range from an uncomplicated fever of unknown origin to a fulminating hemorrhagic disease. Baseline mapping of lassa fever virology, epidemiology and vaccine. Lassa fever is caused by a single stranded rna virus and is a disseminated systemic primary viral infection. Pdf we report the epidemiology of lassa fever in bauchi state, a diseaseendemic region, in nigeria. Of the cases reported so far in the nigerian outbreak, the mortality rate is 43. Infection with lassa virus in humans may take many forms.
Lassa fever lf is a viral hemorrhagic disease caused by the lassa virus lasv. Lassa fever, nigeria, 20052008 volume 16, number 6june. Lassa fever, a new virus disease of man from west africa. As part of efforts to contain an outbreak of lassa fever in nigeria that has infected up to 450 people in 17 states within five weeks, the world health organisation who, on tuesday, announced it. Most of the participants knew correctly that lassa fever can affect all age groups 91. Pdf epidemiology of lassa fever and factors associated with. An arenavirus was isolated from two of these patients and given the name of lassa virus after the town of lassa, nigeria, where the disease, known as lassa fever, occurred buckley et al. Lassa fever is a viral, hemorrhagic causes bleeding disease found in tropical regions of africa.
Lassa fever disease lassa fever is viral illness that occurs in west africa. Pdf epidemiological trends of lassa fever outbreaks and. Epidemiological trends of lassa fever outbreaks and insights for future control in nigeria article pdf available january 2017 with 2,184 reads how we measure reads. Among these, 2 cases have been confirmed, as of february 4, and 40 people.
Benin was last affected by lassa fever over a 4 monthperiod in 20142015 when 16. The disease is highly contagious and spread like wild fire. The lassa fever outbreak in west africa continues to gather momentum. Less commonly there may be bleeding from the mouth or gastrointestinal tract. Lassa virus is one of more than 25 causative viruses of viral hemorrhagic fever table 4. When symptoms occur they typically include fever, weakness, headaches, vomiting, and muscle pains. Pdf lassa fever lf is a zoonotic disease associated with acute and potentially fatal hemorrhagic illness caused by the lassa virus lasv, a member. In 2014, no cases of lassa fever or other arenaviruses responsible for viral haemorrhagic fevers were reported in the eueea. Estimating the true incidence and mortality of lf is extremely difficult due to the nonspecific clinical presentation.
Lassa fever is a viral illness that occurs in west africa. Lassa fever was confirmed in casepatients 3 and 4 by rtpcr as well as by igm and igg seroconversion in the surviving patient casepatient 3. Each year, an estimated 300,000 people are infected, and severe cases can be fatal. Lassa fever is endemic in parts of west africa including sierra leone, liberia, guinea and nigeria. Sequencing the gp and l gene pcr fragments showed that casepatients 3 and 4 were infected with the. Failure of the nigerian health system to prioritise preparedness activities has been detrimental for prompt control of lassa fever, which requires robust laboratory.
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