Fasina_39-46.indd

INTRODUCTION

Fifty-nine countries, including Nigeria, have been
affected by highly pathogenic notifiable avian influ-
enza (HPNAI) H5N1 strains since 2004 (OIE 2006;
WHO 2006). The livestock sector, especially poul-
try, plays a very important economic role within the
resource poor populations of the developing nations
of the world. It provides food (animal protein), in-
come, employment and foreign exchange for coun-

tries that trade their animals and animal products
(Sonaiya, Branckaert & Gueye 1999; McDermott,
Coleman & Randolph 2000; FAO 2002).

The poultry sector represents a major source of in-
come in Nigeria. It contributed approximately 4.45 %
of the total animal contribution to the agricultural
gross domestic product (GDP) in 2004 (Central Bank
of Nigeria 2004). The over 140 million birds are com-
posed of about 60 % backyard poultry stock and
about 40 % commercial or semi-commercial birds
(Adene & Oguntade 2007). About 75 % of the com-
mercial birds are layer stock and they are responsi-
ble for the mass production of eggs and poultry meat
in Nigeria. Poultry is vitally important to the rural poor
since it is the most widespread form of livestock in
Nigeria that the poor rural individuals can afford to
keep as a source of income and assets. However,
estimating the economics and other financial param-
eters in the Nigerian poultry industry is extremely

Onderstepoort Journal of Veterinary Research, 75:39–46 (2008)

The financial cost implications of the highly
pathogenic notifiable avian influenza H5N1 in
Nigeria

F.O. FASINA1, 2*, M.M. SIRDAR3 and S.P.R. BISSCHOP2

ABSTRACT

FASINA, F.O., SIRDAR, M.M. & BISSCHOP, S.P.R. 2008. The financial cost implications of the
highly pathogenic notifiable avian influenza H5N1 in Nigeria. Onderstepoort Journal of Veterinary
Research, 75:39–46

Nigeria and several other nations have recently been affected by outbreaks of the Asian H5N1 strain
of highly pathogenic notifiable avian influenza (HPNAI) virus, which affects the poultry sector most
heavily. This study analysed previous methods of assessing losses due to avian influenza, and used
a revised economic model to calculate costs associated with the current avian influenza outbreaks.
The evaluation used epidemiological data, production figures and other input parameters to deter-
mine the final costs. An infection involving 10 % of the commercial bird population will cost Nigeria
about $245 million and a worse scenario may lead to a loss of around $700 million. The results urge
governments to invest more in measures aimed at the effective prevention of HPNAI and to consider
the huge economic losses associated with the disease. Finally, an inter-disciplinary approach to man-
aging and controlling HPNAI outbreaks is encouraged.

Keywords: Avian influenza, economics, HPNAI, H5N1, Nigeria, poultry

* Author to whom correspondence is to be directed. E-mail:
daydupe2003@yahoo.co.uk

Viral Research Department, National Veterinary Research
Institute, Vom, Nigeria

2 Poultry reference Centre, Department of Production Animal
Studies, Faculty of Veterinary Science, University of Pretoria,
Onderstepoort, 0110 South Africa

3 Military Cooperative Corporation, Khartoum, Sudan

Accepted for publication 21 August 2007—Editor

Financial cost implications of avian infl uenza H5N1 in Nigeria

difficult since data collection is often incomplete or
fragmented.

HPNAI has caused high levels of mortality, restric-
tion in international trade, infection of various animal
species, endangered food security and carries po-
tential for a human pandemic (FAO 2002; European
Commission 2004; Otte, Nugent & McLeod 2004;
Holtz-Eakin 2005; Rushton, Viscarra, Bleich & Mc-
Leod 2005; Ducatez, Olinger, Owoade, De Landt s-
heer, Ameerlaan, Niesters, Osterhaus, Fouchier &
Muller 2006; OIE 2006). Increasingly, cases of
emerging and re-emerging livestock diseases as
well as diseases with emergency potential like
HPNAI, are becoming more connected with higher
densities of livestock, increasing trade resulting in
the movement of people and products and breaches
in biosecurity at various levels (national, regional
and farm), despite improving technologies and ad-
vances in information dissemination and manage-
ment practices.

Although diverse aspects of the avian influenza vi-
rus are being investigated worldwide, studies on the
socio-economic aspects of avian influenza are lim-
ited (Otte et al. 2004; Holtz-Eakin 2005). Losses
associated with livestock diseases may be easy to
identify, but it is extremely difficult to attach a cost
implication, and these cost implications are often in-
complete (Howe 1985; Otte et al. 2004; Holtz-Eakin
2005).

A review of socio-economic evaluation models of
previous workers indicated that the cost of any illness
is the sum total of direct, indirect, intangible and con-
trol costs (Oluokun & David-West 1981; Lasley 1986;
Rushton, Thornton & Otte 1999; Szucs 1999; Otte
et al. 2004; Verbiest & Castillo 2004; Holtz-Eakin
2005; World Bank 2006a). Such a model was used
earlier by Oluokun et al. (1981) in evaluating costs
associated with a Rinderpest outbreak in Nigeria.
Hanson & Hanson (1983) also suggested that loss
of any kind must be interpreted in terms of popula-
tion at risk, and that knowledge of morbidity and
mortality rates are important in estimating the cost
implication.

The costs due to HPNAI outbreaks is less signifi-
cant than those associated with the post outbreak
effects on market, trade, enzootic potential, produc-
tivity, dwindling interest in poultry enterprises and
the attendant zoonotic and food security risks. In
this study, each of these factors was considered in
estimating the cost implications of HPNAI on the
commercial layer industry, based on the population
affected, the population at risk and economics of al-

ternative control measures. These evaluations math-
ematically estimate the cost implications of HPNAI
H5N1 in Nigeria, and the implications for disease
control are discussed.

MATERIALS AND METHODS

For the financial cost evaluation of HPNAI in Nigeria,
the actual situation and scenarios of mild (10 %) and
severe (70 %) generalised outbreaks in the com-
mercial flocks were selected. In Nigeria, the com-
mercial layer is very important, accounting for al-
most 90 % of all egg production (Adene & Oguntade
2007). Similarly, ~99 % of all infected poultry popu-
lations are commercial layers and layer breeders
(data retrieved from National Veterinary Research
Institute, Nigeria, December 2006). Our estimates
deal only with this segment which often operates
with little to no biosecurity.

A number of assumptions were made:

1. HPNAI caused 100 % mortality in affected flocks,
either through pathologic death or control meas-
ures by destruction.

2. One hundred percent cessation in egg produc-
tion was assumed, based on published reports
(Capua & Marangon 2000).

3. HPNAI caused a loss of 6 months in layer/layer
breeder systems (downtime and raising new stock
to point of lay).

4. Laying birds were in full production and would
lay 284 eggs (80 % production) for one laying cy-
cle, and layer breeders would lay 265 eggs (75 %
production). Fifty percent of the breeders’ off-
spring would have market value (pullet) and 50 %
would be cockerels with zero value. Two hundred
chicks per breeder hen are expected and approx-
imately 100 of these chicks will be valued stock
(average production standards).

5. All deaths in the poultry population in Nigeria oc-
curring during the study period (January to August
2006) arose from HPNAI or factors associated
with it.

Other baseline data were obtained from Resource
Inventory Management, Nigeria National Livestock
Resource Survey and FAOSTAT-GLIPHA (FAO
2006a, b and c).

It is difficult to place an economic value on human
beings affected by HPNAI. The affected human pop-
ulation was not economically assessed. Prevention
of the spread of the disease in livestock would pre-
vent its introduction in the human population.

F.O. FASINA, M.M. SIRDAR & S.P.R. BISSCHOP

Mathematical models

Ci = PS {ʊ + β + δ + γ}
Or Ci = PSʊ + PSβ + PSδ + PSγ
Where Ci = cost implications

P = Population of poultry

S = Susceptibility rate of population

ʊ = Direct losses: losses from mortalities (cost due to mortality of
poultry and values of chicks lost from breeders)

β = Indirect losses: egg and meat loss (value of direct loss of eggs
due to yield reduction, cost of rejection of poultry meat and
eggs, and cost associated with glut)

δ = Intangible losses: opportunity cost (cost of rearing replace-
ment stock to production or sale point, cost of feeding to point
of production, cost of retaining facilities and staff during down-
time and rearing stage, and cost of destroying remaining pop-
ulation of animals)

γ = Miscellaneous costs (cost of intense campaign to win back
consumer confidence, cost of control and administrative/gov-
ernmental policies, and external inputs)

* All calculations were done in Naira (N) (Nigerian currency)
and converted to US Dollars ($) at an exchange rate of $1 =
N128.50. Details of final data used for the calculations are
found in Tables 1 and 2.

Total chicken population in Nigeria = 140 000 000

Commercial chickens = 40 % of 140 000 000
= 56 000 000

Commercial layers and layer breeders = 75 % of 56 000 000
= 42 000 000

Commercial layers = 90 % of 42 000 000
= 37 800 000

Layers in production = 75 % of 37 800 000
= 28 350 000

At 80 % hen-day production:

Number of eggs per day = 22 680 000

Number of eggs per annum
[eggs in 12 months (365 days)] = 8 278 200 000

Total number of trays = 275 940 000
(30 eggs per tray) trays per annum

At $2.18 per tray, the total annual
value of eggs from all commer cial
layers will be = $601,549,200

Layer breeders = 10 % of 42 000 000
= 4 200 000

Layer breeders in production = 75 % of 4 200 000
= 3 150 000

At 75 % production:

Total expected chicks per breeder
per annum (100 are saleable pullets) = ~200 chicks

Total expected number of valued
chicks (pullets) per annum = 100 x 3 150 000

If chicks price range between $0.70
and $1.13 with an average of $0.93:

Total value of chicks expected
would be = 100 x 3 150 000 x $0.93
= $294,163,424

Total value of chicks and eggs
expected from layer breeders
and commercial layers = $294,163,424 + $601,549,200
= $895,712,624

Calculating for ʊ (direct costs)

PSʊ1 = Actual determined direct value based on the outbreak
situation (January to August)

PSʊ2 = Estimated direct value based on mild scenario of HPNAI
outbreak (10 % losses in commercial poultry population).

PSʊ3 = Estimated direct value based on severe scenario of
HPNAI outbreak (70 % losses in commercial poultry pop-
ulation).

PSʊ = Market value of birds + value of chicks lost

PSʊ1 = $5,732,460 + $1,074,023 = $6,806,483

PSʊ2 = $37,926,000 + $29,416,342 = $67,342,342

PSʊ3 = $265,482,000 + $205,914,397 = $471,396,397

Calculating for β (indirect costs)

PSβ = Cost (glut)

Costs associated with glut: reduction in price observed x (total
annual national production [trays per annum] – trays lost to mor-
tality in HPNAI)

PSβ1 cost (glut) 1 = ($2.28 – $2.02) x (275 940 000 – 5 650 704)
= $42,068,373

PSβ2 cost (glut) 2 = ($2.28 – $1.56) x (275 940 000 – 27 594 000)
= $154,612,296

PSβ3 cost (glut) 3 = ($2.28 – $1.16) x (275 940 000 – 193 158 000)
= $83,748,327

Calculating for δ (intangible costs)

Since intangible costs are costs of rearing replacement stock,
facilities retention, staff retention, downtime cost and destruction/
disposal of remaining of affected flocks,

therefore PSδ = Replacement cost + downtime cost + destruc-
tion/disposal cost

Replacement cost = (99.985 % cost for raising pullets to POL* +
0.015 % cost for layer breeders pullets to POL) x total number
lost

* POL: Point of lay bird

Downtime cost for facilities = Facility cost per bird per annum
x downtime period per annum x number of birds

N100 per bird per annum† x 3/12 months‡ x number of birds

† $778.21 per 1 000 birds per annum for retaining poultry pen
(field investigations and data from poultry producers, 2006)

‡ Average downtime period is 2–4 months (~3 months)

Destruction/disposal costs are borne by Government as well
as part of the cost of control.

PSδ1 = {(0.99985 x $4.28 + 0.015 x $13.23) x 785 570) + ($0.78
x 3/12 x 785 570)}

= $3,516,156

Financial cost implications of avian infl uenza H5N1 in Nigeria

PSδ2 = {(0.99985 x $4.28 + 0.015 x $13.23) x 4 200 000) + ($0.78
x 3/12 x 4 200 000)}

= $18,798,906

PSδ3 = {(0.99985 x $4.28 + 0.015 x $13.23) x 29 400 000) + ($0.78
x 3/12 x 29 400 000)}

= $131,592,341

Calculating for γ (miscellaneous costs)

Nigerian Government budget allocation for 2005 used as a guide
for 2006.

Compensation reported till date = $182,640 (www.nigeria.gov.
ng/avian%20flu%20center)

TABLE 1 Types and number of birds affected between 10 January and 31 August 2006

Species affected Number Percentage

Chicken: layer/pullet§
Chicken: broiler/cockerel
Chicken: layer breeder
Guinea fowl/quail
Duck/goose
Ostrich*
Turkey
Wild bird (multi species)

770 826
2 755

11 501
19

148
218
101

98.12
0.004
0.015
0.000024
0.000188
0.000278
0.000129
0.0000025

Total 785 570 ~100

§ Include local , backyard and free range laying hens
* Ostriches numbers were estimated based on field investigation

TABLE 2 Parameters used in assessing the economic impacts

S/no. Description Symbol Basic data Actual
scenario

Mild scenario Severe
scenario

1 Population size at risk (layers
and breeders)

P 42 000 000 0.0056 %
(758 570)

10 %
(4 200 000)

70 %
(29 400 000)

2 Susceptible population S 100 % 100 % 100 % 100 %

3 Mortality/disposal 100 % 100 % 100 % 100 %

4 Commercial layer population
affected

37 800 000 774 069 3 780 000 26 460 000

5 Layer breeder population
affected

4 200 000 11 501 420 000 2 940 000

6
Total market value of adult
birds (commercial layer at ~$7
and layer breeders at ~$27.30)

Layer
Breeder

$264,600,000
$114,660,000

$5,418,483
$313,977

$26,460,000
$11,466,000

$185,220,000
$80,262,000

Total $379,260,000 $5,732,460 $37,926,000 $265,482,000

Value of eggs at ~$2.18
(layers only) and meat (old lay
value at ~$4.36/bird) per
annum

Eggs
Meat

$601,549,200
$164,808,000

$15,974,720
$3,374,941

$60,154,920
$16,480,800

$421,084,440
$115,365,600

Total $944,899,200 $19,349,661 $76,635,720 $536,450,040

8 Value of chicks expected $294,163,424 $1,074,023 $29,416,342 $205,914,397

9 Proportion in production 75 % 75 % 75 % 75 %

10 Mean egg price per tray* N280 ($2.18) N260 ($2.02) N200 ($1.56) < N150 ($1.16)

11 Delay in next production
Pre-outbreak
period

6 months 6 months 6 months

* Average egg price derived from field data collected before, during and after the crises period of outbreak. Note that egg price per
tray of 30 eggs was progressively dropping as outbreak situation worsened. Layer represents commercial layers, Bbeeders repre-
sents layer breeders. Other data were derived from UNDP 2006

F.O. FASINA, M.M. SIRDAR & S.P.R. BISSCHOP

Other funds and materials acknowledged by the government in-
clude monetary and non-monetary income.

Monetary income

1. World Bank Special Emergency Fund = $50,000,000 (of
which $7,000,000 has been released (WHO 2006)

2. Three banks = $171,206

Non-monetary income

3. DFID = 15 000 protective personnel equipment (PPE)

4. FAO = 7 500 protective personnel equipment and 750 ℓ (Dis-
kol)

5. WHO = 10 000 doses of Tamiflu

6. USAID = 1 425 protective personnel equipment

7. Israel Government = 1.5 tonnes of medical equipment

Expenditure

Items 3–7 were assessed in monetary value as below:

1. DFID = 15 000 protective personnel equipment = $1,781,250
(at $118.75/PPE*)

2. FAO = 7 500 protective personnel equipment and 750 ℓ (Dis-
kol) (~$20/ℓ†) = $905,625

3. WHO = 10 000 doses of Tamiflu = $800,000 (at $80 per dose
of ten tablets§)

4. USAID = 1 425 protective personnel equipment = $169,219

5. Israel Government = 1.5 tonnes of medical equipment = $??
(details not available to do actual costing)

Total = $2,856,094

* http://www.gallawaysafety.com/disposableprotectivecloth-
ing-c-76.html

§ http://www.coreynahman.com/tamiflu.html

† Price of comparable virucidal (disinfectant) (Onderste poort
Vet erinary Animal Hospital)

Other organisations, including EU and UNICEF, were also ac-
knowledged by the government. Assuming that all other dona-
tions is included in the government spending,

PSγ = 50 % (expenditure items a, b, c, d) + 100 % (expenditure
item e) + reported compensation + non-monetary expenditure

* Note that items a–e are listed in Table 3

PSγ = $108,655 + $155,642 + $182,640 + $2,856,094

PSγ = $3,303,031

PSγ1 = PSγ2 = PSγ3

It is impossible to correlate government spending to the scale of
the outbreak; this amount was left unchanged for all scenarios. It
seems reasonable to assume that this spending would in fact
increase in the event of more severe outbreak.

PSγ = PSγ1 = PSγ2 = PSγ3 = $3,303,031

RESULTS

Using the above values, the total cost implication was calculated
as follows:

Ci = PSʊ + PSβ + PSδ + PSγ

Actual cost implication

Ci = {$6,806,483 + $42,068,373 + $3,516,156 + $3,303,031}
Ci = $55,694,043

Scenario A (mild generalised outbreaks 10 %
commercial flock)

Ci = {$67,342,342 + $154,612,296 + $18,798,906 + $3,303,031}
Ci A = $244,056,575

Scenario B (severe generalised outbreaks 70 %
commercial flock)

Ci = {$471,396,397 + $83,748,327 + $131,592,341 + $3,303,031}
Ci B = $690,040,096

TABLE 3 Budgets and allocations for 2005 fiscal year

Department Classification no. Expenditure items 2005 allocation % estimated to be
spent on HPNAI

FMA&RD 06200002501004 Publicity and advertisement (a) $22,757 50

FMA&RD 02500002000240 Animal disease control (b) $77,821 50

FMA&RD 02500002000241 National veterinary quarantine services (c) $77,821 50

NVRI 02500002000202 Strengthening of central and outstation
laboratories (d)

$38,911 50

NVRI 02500002000205 Research and studies (avian influenza) (e) $155,642 100

Total $372,952 $264,297

FMA&RD Federal ministry of Agriculture and Rural Development
NVRI National Veterinary Research Institute

Source: Nigerian Government (2006a and b)

Financial cost implications of avian infl uenza H5N1 in Nigeria

These costs do not include the price of medical supplies dona-
ted.

Although our analyses did not consider the broiler industry, we
are aware that there was a reported monthly regional export mar-
ket losses of 12 000 tonnes of poultry meat (Personal communi-
cation, Poultry Association of Nigeria 2006). These losses trans-
lated to 144,000 tonnes/annum and at an average cost of N350/kg
of meat, the broiler industry in Nigeria will have recorded annual
direct losses of $392,217,899.

DISCUSSION

In 2004, Nigeria (West Africa’s regional centre for
trade and commerce) had approximately 140 million
poultry of which 119 million were estimated to be
laying birds (FAO 2006a). About 40 % of the total
poultry flock is commercial or semi-commercial and
this accounts for the majority of an annual produc-

FIG. 1 Importance of cost of animal disease outbreak

PeopleResources

Disease

Production

Goods and

services

Consumption

Cost ValueDisease loss

* Input of resources is expected to yield goods and services for the benefit of individuals. Animal disease situations prevent quality
goods and services from reaching human and come at a huge cost and great loss of values

* Adapted from McInerney 1988

FIG. 2 Graphs A and B showing evaluation of cost of animal diseases

Note: Area between standard and disease graph is the cost.
Several other avian diseases cause partial loss of poul-
try production. However, few other diseases attract cul-
ling of the affected flock

P
e
rc

e
n

ta
g

e
p

ro
d

u
c
ti

o
n

100

Weeks in production

Standard Disease

521

The impact of other diseases on egg production B

Note: Area between standard and disease graph is the cost.
HPNAI cause complete loss in poultry production either
through cessation of production, death or culling. Most
of the Nigerian farmers reported above 90 % reduction
in production and the entire flock was finally culled
(100 % loss)

[Analysis of the Nigerian situation]

Weeks in production

P
e
rc

e
n

ta
g

e
p

ro
d

u
c
ti

o
n

100

Standard HPNAI

521

The impact of HPNAI on egg output A

F.O. FASINA, M.M. SIRDAR & S.P.R. BISSCHOP

tion of over 476 000 metric tonnes of eggs (0.8 % of
the world total) and 211 000 metric tonnes of meat
(0.3 % of the world total) (FAO 2006c). Laying hens
contribute huge resources to the national poultry
flock and this emphasizes the importance of com-
mercial layer flocks for Nigeria’s economy. Laying
hens not only have production value, but old birds
(spent hens) also serve as a major source of eggs
and meat for resource poor families.

The Nigerian poultry industry ranks second in im-
portance to petroleum, the country’s major source
of income (Ducatez et al. 2006). Currently, the layer
industry has lost about $60 million as a result of
HPNAI H5N1 between January and August, 2006.
Nigeria’s gross national income was $55.9 billion
and the gross domestic product was $72.1 billion as
at 2004 (World Bank 2006b). This figure, therefore,
is a huge economic loss by any assessment. These
losses are independent of losses associated with
the downstream sectors and broiler industry.

Economists suggest that the price paid for livestock
disease should not be assigned monetary values
alone (Hanson & Hanson 1983; Howe 1985; McIner-
ney 1988). The cost implication of the disease is,
however, important as a starting point to assessing
the true effect of the outbreak (Fig. 1). Previous esti-
mates of the cost of avian influenza outbreaks using
direct costs grossly undervalue costs associated
with HPNAI. A mild scenario of infection affecting
10 % of the commercial laying bird population will
cost the country in the region of $245 million and a
worsening situation may lead to losses of around
$700 million in the layer industry alone.

From the results, any severe outbreaks of HPNAI in
a country like Nigeria will mean an extremely huge
economic loss and will negatively affect the agricul-
tural industry in the subregion.

Graphical representation of the effect of highly path-
ogenic avian influenza (Fig. 2) proved that these
previous methods may not be sufficient to estimate
the cost of this disease. This study considered that
the productive lifespan and the potential value of
the animals involved should be taken into consid-
eration if a comprehensive evaluation of the cost of
animal disease is to be done. A point-of-lay commer-
cial bird or a breeder chicken, although may cost
less than a rooster/broiler or a turkey respectively at
any point, is more valuable than the latter in term of
economic benefit since the laying hen or the breed-
er will bring economic benefit for at least a year.
“Economic value is not simply prices” (McInerney
1988).

Apart from financial losses, the HPNAI H5N1 out-
break also had severe impacts on trade and tour-
ism, created scarcity/unavailability of animal protein
due to public health misconceptions, led to higher
prices for alternative and often lesser quality prod-
ucts, and increased the costs of livestock farming.
There are concerns that HPNAI may become enzo-
otic in the sub-region or in the African continent,
which may then become a source of infection or re-
infection to other parts of the world. Efforts to step
up controls at the borders, surveillance and effec-
tive analysis systems are considered justified by the
huge resources that will be lost due to such out-
break, if calculated over the productive life.

There is a need for restructuring of the poultry in-
dustry which aims for higher levels of biosecurity. A
scientifically based contingency plan and fair com-
pensation schemes also needs to be developed by
all governments. This must be established and test-
ed periodically before the outbreak of any disease,
since time lost to decision-making during disease
outbreaks has huge economic impacts.

CONCLUSION

A separate analysis of the socio-economic changes
forced on the affected farmers and the costs of dif-
ferent control efforts is still necessary to assist the
decision makers in prioritizing all efforts aimed at
controlling HPNAI in Nigeria. An assessment of the
effect of the HPNAI on other categories of service
providers, including day-old-chick suppliers, feed
millers and other input suppliers, the hospitality in-
dustry, and sole traders in poultry products as well
as animal pharmaceutical industries will also be es-
sential to comprehensively assess the overall effect
of HPNAI.

ACKNOWLEDGEMENTS

We thank Dr Celia Abolnik of the Agricultural Re-
search Council at Onderstepoort and Dr Peter Smith
from the Faculty of Veterinary Science for reviewing
the manuscript, and Prof. Bruce Gummow for his
guidance. Data collection was supported in part by
funds provided by the Poultry Reference Centre in
the Department of Production Animal Studies, Fac-
ulty of Veterinary Science, University of Pretoria.

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