The Rising Tide of Lassa fever in Nigeria: Any Role for Libraries?

Introduction

Lassa fever is caused by the Lassa virus. It is a zoonotic disease, meaning that humans become

infected from contact with infected animals. The animal reservoir, or host, of the virus is a rodent

of the genus Mastomys,(M.natalensis), ( Plate 1) ) It is a small soft-furred and naked tailed

rodent, 25 to 27 centimeters long and weighing roughly 60 grammes. It is commonly known as

the “multimammate rat because females have eight to fourteen pairs of tits, instead of the five or

six that is typical of other rodents. Mastomy is a highly prolific breeder, producing a liter of eight

to ten pups monthly, year round (Plate2).. Other rodents of the Mastomys genus had been found

to carry the virus. (Princewill, 2012).

Lassa fever is associated with sporadic infections, during which time the fatality rate can reach

50%.The rats do not become ill but they can shed the virus in their excreta (urine and faeces). (

Ogbuet al, 2007). Lassa fever occurs more in the dry season than in the raining season.

The onset of the disease is usually gradual, starting with fever and general weakness. After a few

days, headache, sore throat, muscle pain, chest pain, nausea, vomiting,diarrhoea, cough, and

abdominal pains may follow. Severe cases may progress to show facial swelling (plate 3) fluid in

the lung cavity, bleeding from mouth, nose, vagina or gastrointestinal tract, and low blood

pressure. Protein may be noted in the urine. Shock, seizures, tremor, disorientation, and coma

may be seen in the late stages. Deafness occurs in 25% of patients of who half recover some

function after 1-3 months. The overall case-fatality rate is 1%, up to 15% among hospitalized

patients (WHO, 2012) Death usually occurs within 14 days of onset in fatal cases. The disease is

especially severe late in pregnancy, with maternal death and/or foetal loss occurring in greater

than 80% of cases during the third trimester. (WHO, 2012)

Persons at greatest risk are those living in rural areas where Mastomys are usually found,

especially in areas of poor sanitation or crowded living conditions. Health care workers are at

risk if proper barrier nursing and infection control practices are not maintained.

Humans usually become infected with Lassa virus from exposure to excreta of infected

Mastomys. Both direct exposure, (touching the excreta) and Lassa virus may also be spread

between humans through direct contact with the blood, urine, faeces, or other bodily secretions

of a person with Lassa fever.

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Plate1.Animal Host: Mastomynatalensis

Source (Centre for Diseases Control (CDC), 2002)

Plate2Mastyomyswith Litters .Source This Day Newspaper (This Day Live)

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Plate 3: A Lassa fever patient showing swollen of the eyes

Source: Lassa fever picture (www.picsearh.com )

The onset of Lassa fever is initially difficult to diagnose and has nonspecific clinical symptoms

which have been confused with yellow fever and typhoid. There is evidence of persistent

infection, it is tremendously contagious, and has a high mortality ( Tomoriet al 1988).. Lassa

fever is one of the endemic zoonosis in Nigeria with a high probability for nosocomial

transmissions due to several health care sector challenges. Although treatment is available for

Lassa fever, early diagnosis is still difficult in almost all Nigerian health institutions. (Fabiyiet al.

1988)

Nigeria is currently being ravaged by Lassa fever. Federal Ministry of Health Weekly

Epidemiology Report that indicates Lassa fever has been reported from 21 out 36 States of

Nigeria as at 20th April 2012.

Statement of Objective

The sole aim of this paper is:

To present a state of knowledge report on the following:

the symptoms and diagnosis of the Lassa fever,

transmission of the fever,

reported cases of Lassa fever in Nigeria,

mortality of Lassa fever

preservation and control of Lassa fever,

treatment of Lassa fever

roles of libraries in reducing the menace of the disease.

.

Information gathering tools

The information gathering tools used for this research are:

Literature search

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Newspaper reports

Discussion with colleagues and neighbours

Symptoms and Diagnosis

The onset of Lassa fever is insidious, with gradual feeling of fever and shivering accompanied

by malaise, headache, generalized aching frequently with pain behind the sternum and a sore

throat. This may be accompanied by nausea, vomiting, diarrhoea or cough. There may be

patches of white or yellowish exudates and occasionally small vesicles or shallow ulcers on the

tonsils and pharynx and this is an important diagnostic feature. As the illness progresses the

body temperature may rise to 41ºC with daily fluctuations of 2-3ºC. Fever is very variable,

occurring constantly or in peaks, and lasting on average for 16 days; extremes of 6-30 days

have been reported.

Additional common symptoms include; abdominal pain, diarrhoea, or constipation,

conjunctivitis, Skin rashes and jaundice occur in rare cases. (WHO. 2012)

Some patients may experience bleeding from the gums. In addition, capillary lesions cause

haemorrhaging in the stomach, small intestine, kidneys, lungs, and brain. Less than 30% of

patients present with bleeding; this is a predictor of a significantly higher risk of death (Tomoriet

al 1988). In severe cases of Lassa fever, shock and vascular collapse occur, followed by

death. Patients who will survive begin to recover 2-3 weeks after onset of the

disease. Temporary or permanent deafness in one or both ears occurs in 29% of Lassa fever

patients. (WHO , 2002)

Complications of the disease after recovery include hair loss, loss of coordination, psychiatric

syndromes (such as mania, depression, dementia, psychosis and sleep disorders) and the most

common, deafness, which occurs in about 30 % of the patients. (Solbrig 1993).

Because the symptoms of Lassa fever are so varied and non-specific, clinical diagnosis is often

difficult, especially early in the course of the disease. The fever is difficult to distinguish from

many other diseases which cause fever, including malaria, shigellosis, typhoid fever, yellow

fever and other viral haemorrhagic fevers.

Transmission of the fever

There are a number of ways in which the virus may be transmitted, or spread, to humans. The

Mastomysrodents shed the virus in urine and droppings freely throughout their lifespan and their

saliva. The virus can be transmitted through direct contact with these materials, through touching

objects or eating food contaminated with these materials, or through cuts or sores. (Adewuyiet

al, 2009). Because Mastomysrodents often live in and around homes and scavenge on human

food remains or poorly stored food, transmission of this sort is common. Contact with the virus

may also occur when a person inhales tiny particles in the air contaminated with rodent

excretions. This is called aerosol or airborne transmission. Finally, because Mastomys rodents

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are sometimes consumed as food, infection may occur via direct contact when they are caught

and prepared for food.

Lassa fever may also spread through person-to-person contact. This occurs when a person comes

into contact with virus in the blood, tissue, secretions, or excretions of an individual infected

with the Lassa virus..

Humans can contract the disease from other humans via aerosol transmission (coughing), or from

direct contact with infected human blood, urine, or semen.

Risk to Health care workers

Human to human transmission is common in both village and health care settings, where, along

with the above-mentioned modes of transmission, the virus also may be spread in contaminated

medical equipment, such as re-used needles (This is called nosocomial transmission.)

Health workers are not spared in the recorded infection and consequent death by this disease;

From the first reported case 43 years ago to this year’s outbreak, doctors and nurses have not

been spared from the devastating effects of the disease (Ruby,2012) .So far from available

records not less than ten hospital workers including the Chief Medical Director of Igboji

General Hospital Ikwo in Ikwo Local Council of Ebonyi State have died from the disease.

Prevention and control of Lassa fever in Nigeria

Prevention of Lassa fever in Nigeria communities can be based on promoting personal and

community hygiene to prevent people from coming into contact with rodents which are common

in dirty environments, clean environments will reduce the rat population.

Effective measures include storing grains and other foodstuffs in rodent-proof containers,

disposing of garbage far from the home, proper covering of food, discarding food eaten by rats

maintaining clean households and keeping cats.

Family members and health care workers should always be careful to avoid contact with blood

and body fluids while caring for sick persons. Routine barrier nursing precautions probably

protect against transmission of Lassa virus in most circumstances. However, for added safety,

patients suspected to have Lassa fever should be cared for under specific isolation precautions,

which include the wearing of protective clothing such as masks, gloves, gowns, and face shields,

and the systematic sterilization of contaminated equipment

However, the wide distribution of Mastomys in Africa could make complete control of this

rodent reservoir a great challenge

Reported cases of Lassa fever in Nigeria

A summary of the reported cases of Lassa fever in Nigeria is shown in Table1

This table shows alarming numbers for 2012. The report from the Federal Ministry of health

weekly update up to 20th April 2012 shows that there were altogether 136 confirmed

cases from 21 States of the country.

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Mortality

From the data in table 1, the mortality rate of Lassa fever is very high. Between 1969 and

2012 a total of 1088 cases of Lassa fever were reported out of which 357 were clinically

confirmed with 230 deaths representing 64.4 %.The highest outbreak is 2012 where 136

people were infected with 87 deaths representing 63.9 %. Efforts must be geared towards

reducing the menace of the disease in the next dry season.

Table 1: Reported cases of Lassa fever

S\N Date/Year State Cases

Reported

Clinically

confirmed

Mortality

1 1969 Lassa (Borno State) 2 2 1

2 1970 Plateau State 28 28 13

3 1989 Edo State 34 22 20

4 1995 Imo State, Edo State 34 34 20

5 2005 Ebonyi State 4 4 2

6 2007 Edo, Taraba and

BornoStates

55 55 40

7 2008 Federal Capital

Territory(Abuja) and

Plateau State

4 4 4

8 2009 Edo State 7 7 5

9 2010 Kebbi State 22 22 17

10 2011 Edo, Taraba, Ebonyi,

Ondo, Plateau and

Rivers, Borno States

50 50 26

11 2012 Ebonyi, Borno,

Gombe,RiversPlateau,An

ambraYobe, Edo,

Lagos,Kogi,Kebbi,

Taraba

,Ondo,DeltaKano,Nassar

awa, Plateau and

Imo,Oyo, Adamawa

States and FCT (Abuja)

855 136 87

Total 1088 357 230

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Treatment of Lassa fever

No vaccine for Lassa fever is currently available for use by humans, and the only available drug,

ribavirin, is only effective if administered early in infection (within the first 6 days after disease

onset).

Discussion

The analysis of reported cases of Lassa fever is presented in Tables 2 and 3. It will be observed

that between 1969 (when the first case was reported) to this year 2012, five States were affected

only once, but eight states had been affected more than once (Table2). Of greatest concern is the

increase in number of cases from 2011 to 2012.

This calls for concern and prompt intervention from the stakeholders to prevent the spread of this

disease to other parts of the country not yet affected and to stop re-occurrence in the affected

States.

Table 2: Recurrence of reported cases of Lassa fever in Nigeria

No of years

diseases are

reported

Number of State(s)

concerned

1 year only 5

2 different

years

2

3 different

years

3

4 different

years

2

6 different

years

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Table 3: Number of states of reported cases of Lassa fever in Nigeria

Date/years Number of States

1969 1 State

1970 1 State

1989 1 State

1995 2 States

2005 1 State

2007 3 States

2008 2 States

2009 1 State

2010 1 State

2011 7 States

2012 21 States

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From only one State (Borno State) where this disease was first discovered in 1969, the tide gradually increased

to 3 states by 2010. In 2011, there was a sharp increase to 7 seven states. This year the number jumped to 21

states. The time for action is now, especially in the two states where cases had been in four different years and

particularly Edo State where cases have been reported in six different years. (Table 3)The high mortality rate for

Lassa fever infection is shown in Figure 2. The lowest reported mortality was46.4% in 1970 and it can be 100%

as in 2008.

The following reasons account for the rising tide of Lassa fever in Nigeria:

Many Nigerians especially in the rural areas are oblivious of the diseases

There is the problem of self-medication .Many Nigerians prefer to self-medicate.

Hospitals are usually the last resort and in the case of Lassa fever it might be too late

Culturally in the rural areas, farm produce are sun dried on the road sides where they are

exposed to infection with rat urine and faeces. Rats are consumed in many rural areas.

Lack of Government policy on the control and eradication of Lassa fever especially at the

state and local government levels. At present, only two laboratories in the country ( Irrua

Specialist Hospital ( ISH) in Irrua, Edo State and the Central Medical Laboratory at the

Lagos University Teaching Hospital (LUTH) )have the capacity to screen blood for Lassa

virus. A high percentage of cases of Lassa fever referred to ISH end up in death because

they are referred late and have to travel long distance to Irrua.

The level of campaign against this disease is still low especially in rural areas.

0

20

40

60

80

100

120

Mo

rtali

ty p

erc

en

tag

e

Year

Fig 2 :Percentage mortality for each year of reported cases of Lassa fever

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The Role of Medical Libraries and Medical Librarians

The activities of Medical Librarians should be oriented towards the goal of producing a healthy

society as well as assisting the individual in making informed health decisions. Librarians should

help physicians, allied health professionals and researchers to stay abreast of new developments

in their speciality areas. (King, 1987)

Medical librarians provide access to resources in a variety of formats, ranging from traditional

prints to electronic sources and data (Nail, 2006). Librarians are expected to work towards the

social and community goals of producing a healthy society as well as assisting the individual to

make more informed health decisions.

The roles of Medical libraries in curbing the rising tide of Lassa fever in Nigeria include

but not limited to the following:

Providing quality information on Lassa fever as an emerging disease.

Creating awareness on the causes, symptoms and prevention of Lassa fever.

Providing educational programs for the general public on locating and evaluating

information on Lassa fever.

Providing a current awareness service about Lassa fever for health professionals

Initiating and participating in research that can curb and eventually lead to the

eradication of the disease.

Sending information to hospitalized patients and community members about the disease.

Collaborating with government and non-governmental organizations in packaging,

repackaging and promoting health information

Collaborating with community health workers and other agencies to mobilize and

educate community members on this dangerous emerging diseases

Conclusion and Recommendations

It is imperative that an intensive and comprehensive awareness be carried out to curb the rising

tide of Lassa fever in Nigeria and the roles of libraries in accomplishing this task cannot be

emphasised.

Intensive awareness campaign for the eradication of Lassa fever

Campaign for the control of Lassa fever must be intensified more than ever before. The war

against the disease must be fought collectively to achieve the desired result of preventing a

deadly, emerging epidemic. All the members of the community must be sensitized of the

possibility of eradication through prevention. To achieve this, the following must be done

without further delay:

There must be nationwide media publicity on the spread of the disease across the country.

All categories of libraries must be stocked with materials on symptoms, prevention and

control of Lassa fever.

In collaboration with radio and television stations, the ministries of information should

feature drama and playlets that inform people about the disease.

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The literate members of the community should be reached through the billboards,

newspaper and magazines, posters, pamphlets and handbills.

Traditional rulers and chiefs should be enlightened about the disease and they in turn will

enlighten their subjects.

Mothers should also be made aware of the epidemic of Lassa fever and that they should

desist from self-medication but refer all cases of fever in the hospital because it could be

Lassa fever.

Health officials especially in endemic areas must go round the villages and outlets to

ensure proper maintenance of deep well and water reservoirs.

Farmers should be enlightened on danger of spreading farm products on the road side and

open places.

The rural dwellers should be discouraged from eating any type of rat.

It is expected that if all these measures are taken, there is the possibility of complete eradication

of Lassa fever in Nigeria. The case of Jigawa State where the outbreak of Lassa fever was

prevented through public awareness is a pointer to the possibility of eradication of Lassa fever in

the states of Nigeria

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References

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features and current management Review of Literature ‘African Journal of Clinical and

Experimental Microbiology;(3)1: 32-37 Retrieved from www.ajol.info.org

2. Adewuyi, G.M, Fowotade.A and Adewuyi, B.T.( 2009) Lassa fever another infectious

menace. African Journal of Clinical and Experimental Microbiology 10(3):144-155

Retrieved from www.ajol.info.org

3, Akpan, Nnamdi (2012) Lassa fever kills CMD in Ebonyi’ Retrieved from

www.dailytimes.com.ng

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Journal of Virology 74(15):6992- 7004 Retrieved from www.ajol.info.org

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Tribune Limited Ibadan, page 26.

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Ebola viruses by gamma irradiation. Journal of Clinical Microbiology16:704-708.

8. Fabiyi, A, Tomori, O and McCormic, J.B, Viral haemorrhagic fever antibodies.( 1988).

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www.fmh.org

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13. Princewill, Tonye (2012 February 17). Lassa fever…. And the joker was death.

Retrieved from www.vanguard.ngr.com

14. Ruby, Leo (2012 February 13).Lassa fever kills six health workers 34 others.

Retrieved from www.dailytrust org.ng

15. Solbrig, Marylou. (1993) Lassa Virus and Central Nervous System Diseases Plenum

Press, New York.: page 325-329

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Haemorrhagic fever antibodies in Nigeria populations. African Journal of Tropical

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