Full text of DOI:10.2165/00019053-200119040-00006

Pharmacoeconomics 2001; 19 (4): 391-400
1170-7690/01/0004-0391/$22.00/0
ORIGINAL RESEARCH ARTICLE
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Cost-Benefit Analysis of a
Haemophilus Influenzae Type B
Meningitis Prevention Programme in
The Philippines
M. Rhona M.T. Limcangco,1 Carol L. Armour,2 Eugene G. Salole2 and Susan J. Taylor2
1
2
Department of Pharmacy, College of Pharmacy, University of the Philippines – Manila,
Manila, Philippines
School of Pharmacy, University of Sydney, New South Wales, Australia
Abstract
Background: Haemophilus influenzae type b (Hib) meningitis is associated with
high mortality and serious sequelae in children under 5 years of age. Vaccines
which can prevent this infection are available.
Objective: To evaluate the costs and benefits of a 3-dose immunisation schedule
in Manila, Philippines.
Perspective: Government and societal perspectives.
Design and participants: A cost-benefit analysis based on a birth cohort of
100 000 children. The state of health of the cohort with and without a Hib im-
munisation programme was modelled over a 5-year period. A survey of medical
records of patients with Hib in Manila provided data on the extent and cost of
sequelae following infection.
Intervention: A 3-dose Hib vaccination programme given at ages 2, 3 and 4
months.
Results: The model predicted that vaccinating children against Hib meningitis
would prevent 553 cases per year in a birth cohort of 100 000, at a cost of 56 200
Philippine pesos (PHP) [$US1605; 1998 exchange rate] per case (base case as-
sumptions of 90% vaccine efficacy rate, 95 per 100 000 Hib incidence rate, 85%
vaccination coverage). Results from the cost-benefit analyses indicated that the
saving to the government would be around PHP39 million ($US1.11 million),
and the saving to society would be PHP255 million ($US7.28 million).
Conclusion: There would be a positive economic benefit for the Philippine gov-
ernment and for the Filipino society if a Hib vaccination programme was intro-
duced in Manila.
Haemophilus influenzae type b (Hib) meningitis
incidence rate is higher than the incidence rates in
other non-western populations (which range from
25 in Chile[2] to 60 in The Republic of Gambia[3,4]
per 100 000 of children <5 years of age) and in
is a significant problem in Manila, Philippines as
demonstrated by the high incidence rate of 95 per
100 000 in children less than 5 years old.[1] This

392
Limcangco et al.
western populations (20 to 50 per 100 000 of chil-
dren <5 years of age).[5-7] However, it is much lower
than the incidence rates reported for indigenous pop-
ulations (which range from 475 per 100 000 for
indigenousAlaskans[4] to 530 per 100 000 children
<5 years for Canadian Inuit[8]). In the Philippines,
as in other countries, not only does Hib meningitis
have a relatively high mortality rate (11%), it is
also associated with a high rate of sequelae (15%).
The reported sequelae include hearing loss, ataxia,
mental retardation, speech delay, obstructive hydro-
cephalus and visual impairment.[9,10] Fortunately,
Hib meningitis can be prevented using effective vac-
cines.[11]
Since Hib conjugate vaccines have become avail-
able, a number of economic studies have been per-
formed in various countries; results from these anal-
yses support vaccination.[12-21] However, no such
evaluation has been conducted in the context of the
Philippine health environment. In this study, we
performed a cost-benefit analysis of the possible
implementation of a Hib vaccination programme in
Manila. All future costs associated with long term
health effects from Hib meningitis were consid-
ered. The perspective taken is that of the govern-
ment and of society.
modelled each month for a 5-year period. Asimpli-
fied diagram of the model is presented as a decision
tree in figure 1; the model was assessed for face
and content validity by a clinical epidemiologist
and by 2 infectious disease experts. Each month
starting from birth, children in the cohort have a
given risk of developing Hib meningitis. If, by
chance, the child develops Hib meningitis, he or
she has a given risk (or probability) of developing
either severe or mild sequelae, of dying or of full
recovery. Children who develop Hib meningitis leave
the cohort, and those who do not develop Hib men-
ingitis pass through the next period and become the
population at risk of Hib meningitis on the suc-
ceeding month. This cycle continues until the chil-
dren in the cohort reach the sixtieth month.
Two strategies against Hib meningitis were
analysed. These were: (i) a no vaccination pro-
gramme; and (ii) a government-funded vaccination
programme coinciding with the usual DTP sched-
ule at 2, 3 and 4 months. Table I lists the assump-
tions used in estimating the outcomes of the Hib
vaccination programme in Manila.
Costs
Discounting
Costs were expressed in Philippine pesos [PHP;
$US1 = PHP35 (1998 exchange rate)]. All future
costs were converted to 1998 dollar values using
discounting[28] at a rate of 5% per year.
Methods
Epidemiological Data and the Model
Data from an epidemiological study conducted
in Manila[1] were used. Hearing loss, originally cate-
gorised as a severe sequela in the study, was reclas-
sified as a less severe outcome to conform to the
classification used by other studies.[14,16] The number
of cases that would occur with and without the im-
munisation programme in a birth cohort of 100 000
children until they reached 5 years of age was esti-
mated using a similar model to that used by Harris
et al.[14] to estimate Hib meningitis incidence and
outcomes. A 5-year cohort was chosen because men-
ingitis infection most often occurs in this age range.
Using a spreadsheet program, Microsoft Excel
version 5.0,[22] the state of health of the cohort with
and without a Hib immunisation programme was
Cost of Hib Meningitis
The items included in the cost-benefit analysis
and their associated costs are listed in table II. It
was assumed that all cases had a 15-minute visit to
a GP before referral to hospital. The cost of the
length of hospital stay was derived using the cost
per day of stay in a ward and in an intensive care
unit. Hospital costs were based on the average costs
of treatment in a standard ward and in an intensive
care unit per day for medical care, tests and drugs.
All costs were determined from the Philippine Gen-
eral Hospital costs.
It was assumed that all children who experien-
ced some form of moderate disability as a result
of Hib meningitis would require special education
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Pharmacoeconomics 2001; 19 (4)

Severe
sequelae
Neurological
sequelae
Moderate
sequelae
Survive
Hib meningitis
No sequelae
Die
No vaccination
Survive
No Hib meningitis
Die
Severe
sequelae
Neurological
sequelae
Moderate
sequelae
Survive
Die
Meningitis before
age of vaccination
No sequelae
Severe
sequelae
Neurological
sequelae
Moderate
sequelae
Survive
Effective
Hib meningitis
No sequelae
Vaccinate
Vaccinate
Die
Not effective
Survive
No Hib meningitis
Die
No meningitis before
age of vaccination
Severe
sequelae
Neurological
sequelae
Moderate
sequelae
Survive
Hib meningitis
No sequelae
Die
No
vaccination
Survive
No Hib meningitis
Die
Fig. 1. Decision tree diagram of Haemophilus influenzae type b (Hib) meningitis prevention strategies. Circle = chance node; square = decision node; triangle = outcome.

394
Limcangco et al.
Table I. Summary of variables used to estimate the outcomes of
Haemophilus influenzae type b (Hib) vaccination in Manila
the Philippines and was therefore not considered as
an option.
Variable
Value
Additional costs incurred by one of the parents
taking time off work to care for their child in hos-
pital (including 5 days after discharge) as well as
travel costs were taken into account. Costs incurred
by a parent whose child had severe disability were
calculated as follows: it was assumed that full-time
care would have to be provided by a parent at a
yearly cost of PHP52 000, equivalent to the current
yearly minimum salary (with a 10% increase every
5 years).
Although difficult to estimate, the value of a
life lost was estimated using the human capital ap-
proach;[29] the loss of income from the age of 20
years up to the age of 65 years (had the child sur-
vived in full health) was estimated. Annual earn-
ings of PHP52 000 (based on the minimum wage),
with a 10% increase every 5 years, was used in
calculating future earnings of an individual. Be-
cause not everyone will be employed, the national
unemployment rate of 9%[27] was factored in the
calculation.
Hib meningitis incidence per 100 000 children <5 95[1]
years old
Probability of all causes of childhood mortality
per 100 000 birth cohort[23]
<1 year of age
0.0582
1-5 years of age
0.0168
0.110
0.828
0.172
0.388
0.612
100 000
65
Case fatality rate[1]
Probability of no sequelae[1]
Probability of sequelae[1]
severea
moderateb
Annual birth cohort
Life expectancy (years)[23]
full recovery
65
with moderate sequelaeb
with severe sequelaea
Vaccine effectiveness[20,24,25]
Vaccination coverage[26]
Vaccination schedule[27]
50
40
90%
85%
2nd, 3rd and
4th month
a
b
Severe physical (e.g. hemiparesis, quadreparesis) and mental
disabilities and severe mental retardation.
Diagnosed sensoneural hearing loss, mild speech difficulties,
diagnosed seizure or epileptic condition controlled by anticon-
vulsant medication, gait abnormality and coordination
problems.
Cost of the Vaccination Programme
Studies have shown that diphtheria-tetanus-per-
tussis (DTP) and Hib vaccines can be safely com-
bined.[24,25] It was, therefore, assumed that the Hib
vaccination programme would be incorporated into
the existing vaccination programme of the govern-
ment; thus, the marginal cost of administration would
be minimal. Table II lists the components of the
programme costs that were considered in order to
provide 3 paediatric doses of conjugate vaccines to
the birth cohort. The total cost of vaccinating a child
was PHP470.80 (table III). The cost of the vaccine
was PHP150 per dose, equivalent to the price per
dose other governments were able to negotiate.[16]
With the inclusion of a Hib conjugate vaccine
in the Expanded Program on Immunization,[30] the
following assumptions were made:
(i.e. having to enrol in a special school for the hear-
ing impaired). The marginal cost of special educa-
tion in Manila was conservatively estimated to be
PHP4000 per year per child.
For children with severe disability or sequelae,
long term care would be required. However, the
cost of long term disability is difficult to measure
with precision; estimates for the costs of different
degrees of disability in the Philippines were not
available. The cost of severe disability requiring
residential care (including costs of home devices and
aids) was conservatively estimated to be PHP12 000
per year.
For children with hearing impairment, the cost
of a hearing-aid was at least PHP10 000; replace-
ment is required every 5 years. Cochlear implant,
a procedure which can have a substantial impact on
children with a hearing deficit, is not available in
1. Five minutes extra public health nurses’time per
vaccination; no extra parental time off work; no
extra transportation costs for either children or par-
ents.
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Pharmacoeconomics 2001; 19 (4)

Cost-Benefit of Meningitis Vaccine
395
2. The costs of storage and wastage were not in-
cluded in the calculation of the programme cost.
However, assuming that wastage is the same as for
oral polio and measles vaccines, then a 33% wast-
age was expected.[31]
3. The cost did not include training components
aimed at increasing the proficiency of public health
workers in promoting the importance of Hib im-
munisation to parents.
actions.[32,38-40] Adverse reactions consist mostly
of localised erythema. Because Hib vaccines would
be given at the same time as DTP vaccines and
because children immunised with DTP exhibit sim-
ilar adverse reactions, it was assumed that no addi-
tional costs would be incurred for the treatment of
this minor adverse reaction to the Hib conjugate
vaccines.
Cost-Benefit Evaluations
Vaccine Efficacy
Cost-benefit analyses were calculated using
Microsoft Excel version 5.0.[22] The analyses in-
cluded direct and indirect costs to the government
and society (table IV). Results were reported as net
benefits of the vaccination programme to the chil-
dren in the birth cohort (costs less benefits). Sen-
sitivity analyses of the estimates and assumptions
in the cost-benefit analyses were conducted by
altering single variables in the base case.
Vaccine efficacy after completing the vaccina-
tion schedule was set at 90% for the 3 conjugate
doses.[32,33] No partial protection after the first and
second dose of the vaccine was assumed; vaccine
protection would be achieved after the third dose,
in which case the vaccine would provide protective
immunity until the fifth birthday.[34,35] Any addi-
tional protection as a result of herd immunity (re-
sistance of a group to an attack by a disease due to
the large proportion of the members of the group
being immune[34,36,37]) was not considered.
Results
In the absence of a preventive intervention against
Hib meningitis there will be 980 new cases per year
for a 100 000 birth cohort in Manila. A 3-dose Hib
vaccination programme that aims to vaccinate chil-
dren at ages 2, 3 and 4 months will reduce this
Vaccine Safety and Complications
Hib conjugate vaccines have been shown to be
well tolerated, with no reported serious adverse re-
Table II. Total Haemophilus influenzae type b (Hib) meningitis costs for the 100 000 birth cohort (in Phillipine pesosa; PHP; 1998 values)
Cost component
Without Hib immunisation
With Hib immunisation
Costs to the government
Initial visit to general practitioner
Hospitalisation
Special education (for children with moderate sequelae)
Total
135 645
133 811 920
58 936 928
192 884 493
59 684
58 877 245
7 385 059
66 321 988
Direct costs to society
Transportation
Loss of income of parents (while the child is in hospital)
Hearing aid
Doctors follow-up and drugs
3 649 731
10 493 400
3 656 279
1 605 881
4 617 096
1 608 763
920 513
2 092 075
Residential care (children with severe sequelae)
Loss of income of a parent (care of children with severe sequelae)
Total
85 796 103
280 406 400
386 093 988
37 750 285
123 378 820
169 881 358
Indirect costs to society
Loss of income (due to death and severe sequelae)
544 114 765
239 410 496
Total
1 071 541 377
527 165 711
a
$US1 = PHP35 (1998 exchange rate).
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Pharmacoeconomics 2001; 19 (4)

396
Limcangco et al.
Table III. Cost per child of Haemophilus influenzae type b conjugate
Additional programme costs could potentially
be eliminated if Hib vaccine is given together with
DTP as a single injection. The marginal labour, sy-
ringe, needle and swab costs would become zero.
The effect of this would reduce the vaccination pro-
gramme costs by PHP1.76 million.
vaccine administration
Variable
Cost per child (Philippine
pesosa; PHP; 1998 values)
Vaccine (PHP150 per dose)
Swab
450.00
0.60
Disposable syringe/needle
Labour
18.00
0.20
Sensitivity analysis was conducted by varying
each parameter used in the model while others were
held constant (table V). In choosing the upper and
lower sensitivity values, the 95% confidence inter-
vals for Hib meningitis incidence rates[1] and vac-
cine efficacy,[41,42] published vaccination rates[30]
and recommended discount rate ranges[43] were used.
Results of the sensitivity analysis showed that vary-
ing the parameters using the specified ranges did
not change the cost-benefit results of the base case.
Indeed, with the worst-case scenarios of 64.8% effi-
cacy or 50% vaccination rate, the vaccine would
still result in a positive cost benefit. The effect of
varying the per dose cost of the vaccine on the cost/
benefit ratio of the immunisation programme is
shown in table VI.
Vaccine carrier/refrigerator
Total
2.00
470.80
a
$US1 = PHP35 (1998 exchange rate).
number to 427 cases per year for the next 5 years,
given the base case assumptions (table I). The ex-
pected outlay by the government for a vaccination
programme for a 100 000 birth cohort is around
PHP40 million.
The results of the cost-benefit analysis applying
the base case assumptions show that the cost of
implementing Hib conjugate vaccination is less than
the cost of Hib meningitis to both the government
and society. Net savings that are several times greater
than the actual programme cost can be achieved
from the societal perspective. From the government
perspective, the prevention programme would pro-
duce a net saving of up to PHP39 million (table IV,
base-case scenario).
Using the gross national product per capita
(PHP32 000 per annum)[27] for valuing life (instead
of using the minimum wage) was also used to as-
sess the impact of patients who developed severe
sequelae or died as a result of Hib meningitis. This
Table IV. Net cost of Haemophilus influenzae type b (Hib) vaccination in millions of Philippine pesosa (PHP; 1998 values) [a negative net cost
indicates a saving]
Variable
Base caseb
Government
–39.0
Societal direct benefits
–255.4
Societal direct and indirect benefits
–560.0
Efficacy
64.8%
100%
–22.0
–84.8
–191.4
–290.6
–21.54
–639.2
Hib incidence rate per 100 000 children <5 years of age
77.5
–24.4
–200.6
–354.8
–449.0
–762.2
111.6
–65.8
Vaccination rate
50%
95%
–19.6
–39.6
–137.6
–313.8
–304.0
–595.6
Discount rate
10%
–33.6
–279.0
–342.2
0%
–350.0
–2403.6
–26 539.4
a
b
$US1 = PHP35 (1998 exchange rate).
Base case: 90% vaccine efficacy, 95 per 100 000 incidence rate, 85% vaccination rate, 5% discount rate and 13% sequelae rate.
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Pharmacoeconomics 2001; 19 (4)

Cost-Benefit of Meningitis Vaccine
397
Table V. Effects of sensitivity analysis on the outcomes and costs of a vaccination programme per 100 000 birth cohort. Costs are in Philippine
pesosa (PHP; 1998 values)
Variable
Cases/sequelae/death
prevented per year
553/74/61
Cost per case prevented
14 400
Cost per sequelae prevented Cost per death prevented
Base caseb
108 200
131 200
170 200
Efficacy
64.8%
100%
430/58/47
615/83/68
18 600
96 400
138 000
117 700
Haemophilus influenzae type b meningitis incidence rate per 100 000 children <5 years of age
77.5
448/60/49
17 800
133 400
163 400
98 800
111.6
740/100/81
10 800
80 000
Vaccination rate
50%
95%
300/40/33
586/79/64
15 680
13 600
117 800
113 200
142 600
139 800
Discount rate
10%
0%
553/74/61
553/74/61
14 400
14 400
108 200
108 200
131 200
131 200
a
b
$US1 = PHP35 (1998 exchange rate).
Base case: 90% vaccine efficacy, 95 per 100,000 incidence rate, 85% vaccination rate, 5% discount rate and 13% sequelae rate.
would have an effect of reducing the total societal
benefit from PHP560 to PHP400 million through-
out the lifetime of the 100 000 birth cohort.
In the Philippines, hospital costs could vary by
up to 20%.[44] Any decrease in hospital cost, how-
ever, would not be substantial enough to be able to
change the result of the analysis from net savings
to net costs from the government’s perspective.
to simulate the effects of a vaccination programme
in a birth cohort. However, in this study, there are
differences in the epidemiological variables used.
This study concentrated on Hib meningitis alone
whereas other studies included other invasive in-
fections associated with the Hib organism, such as
pneumonia, epiglottitis and cellulitis. Also, the in-
cidence rates for Hib meningitis used in this study
are at least 2-fold higher than those used in the
previous economic studies.
Discussion
The low hospitalisation costs reported in Chile[18]
are comparable with the hospitalisation costs in
Manila (PHP26 000 and PHP27 200, respectively).
However, because of the low Hib meningitis inci-
The results of this cost-benefit analysis indicate
that the costs generated by Hib meningitis from the
societal perspective would exceed the costs associ-
ated with a vaccination programme. The Hib menin-
gitis cost to the Philippine society (PHP520 million)
is substantial enough to justify a 3-dose vaccina-
tion programme. Likewise, from the perspective of
the government, Hib vaccination is also a worth-
while intervention; the costs of the programme are
35% less than the costs of Hib meningitis to the
government (PHP62 million). The vaccination pro-
gramme would remain cost beneficial to the gov-
ernment as long as the price per dose of the vaccine
did not exceed PHP360.40 (break-even price).
Similar to a number of economic studies on Hib
vaccination,[13,14,16,45] this study developed a model
Table VI. Cost-benefit ratio of Haemophilus influenzae type b
immunisation programme: sensitivity analysis at varying vaccine
prices
Vaccine price
(Philippine pesos;
PHP)a
Cost/benefit ratiob
government societal direct societal
direct cost
11.73
1.00
0.26
2.60
cost
indirect cost
88.94
7.57
2.02
1.00
20.00
306.40
1166.40
2359.6
43.47
3.72
1.00
0.49
a
b
$US1 = PHP35 (1998 exchange rate).
Total benefit divided by total cost.
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Pharmacoeconomics 2001; 19 (4)

398
Limcangco et al.
dence in Chile (25 per 100 000 versus 95 per 100 000
in this analysis), a low price of Hib vaccine in Chile
was required for the vaccination programme to be
cost beneficial. For a 3-dose vaccine schedule, the
break-even point was reached at a vaccine price of
PHP66.20 in Chile compared with PHP306.40 in
this study (same year of costing). Interestingly, the
break-even point for the Israel Health Service[13] was
reached at a vaccine price of PHP59 in spite of the
relatively low incidence rate of 34 per 100 000 and
hospitalisation costs being around 5-fold higher than
in Chile and in Manila.
In the study from Chile, the costs of any long
term care as a consequence of Hib meningitis were
not measured, thus the main contributor to Hib men-
ingitis cost was the cost of hospitalisation.[18] In
countries where long term institutional care exists,
long term care costs (excluding any measure of
indirect costs), usually dominate Hib meningitis
costs.[12,15,16,45] Long term institutional care costs
for severe cases of Hib meningitis reported from
different countries vary greatly from PHP1.1 to
PHP4.6 million per year (1998 values).[16,20] The
estimate used in this study for long term residential
care was rather conservatively set at PHP12 000
per year and, therefore, long term residential care
only accounted for 16% of the total Hib meningitis
cost. However, if any loss of earnings of parents of
children with severe sequelae were also included
in estimating the costs of long term care, long term
care cost would account for around 69% of Hib
meningitis costs. However, this cost is still a lot less
than that reported in Western countries.[14-16]
If children with disabilities were cared for in
institutions rather than at home, long term care costs
would then become direct costs to the government.
Such an arrangement would make the vaccination
programme even more favourable to the govern-
ment (additional PHP197.6 million savings accru-
ing to government welfare services).
15% change from the base case cost-benefit results,
only vaccine price was able to change the direction
of the net benefit from a saving to a cost. Although
reducing the discount rate to 0% did not affect the
direction of the net benefit, net savings derived from
the Hib vaccination programme increased several
fold, and in the case of total societal cost, 47-fold.
The cost of administering the vaccine could be
reduced if Hib conjugate vaccine in combination
with DTP was used. However, administration cost
is only minor compared with the cost of the Hib
conjugate vaccine itself. On the other hand, if Hib
conjugate vaccination was scheduled separately from
DTP, the additional immunisation visits would in-
crease costs to society due to the additional paren-
tal cost of time off work.
This study is not without some limitations. Not
all benefits were included in the current analysis.
The following additional benefits from the decrease
in the number of cases and deaths as a result of the
vaccination programme were not given any mone-
tary valuation:
1. Reduction in parent distress, pain, and grief over
his or her child having Hib meningitis.
2. Reduction in patient distress, pain, and grief as-
sociated with short and long term sequelae and
death.
3. Increase in external benefits for members of so-
ciety who feel gratified that their society is free
from the risk of Hib meningitis.[13]
Partial protection from the vaccine after the first
and second dose[23,38,46] was not considered in the
analysis. Similarly, additional possible benefits of
Hib immunisation which may be obtained through
herd immunity, were also not considered in the an-
alysis.[34,37] Also, the analysis of benefits of the Hib
vaccination programme did not include the preven-
tion of other Hib infections such as pneumonia. In
a country where pneumonia is considered to be one
of the leading causes of morbidity,[26,47,48] results
of the cost-benefit analysis would only look more
favourable if the benefits of preventing pneumonia
were included.
Other than the cost of the vaccine, other studies
have found that vaccine efficacy, vaccination rate,
discount rate and rate of incidence are the key an-
alytical variables.[13,14,16] This study found that al-
though these variables were able to effect at least a
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Pharmacoeconomics 2001; 19 (4)

Cost-Benefit of Meningitis Vaccine
399
Conclusion
References
1. Limcangco MR, Salole EG, Armour CL. Epidemiology of Hae-
mophilus influenzae type b meningitis in Manila, Philippines,
1994 to 1996. Pediatr Infect Dis J 2000; 19 (1): 7-11
2. Ferreccio C, Ortiz E, Astroza L, et al. Apopulation-based retro-
spective assessment of the disease burden resulting from in-
vasive Haemophilus influenzae in infants and young children
in Santiago, Chile. Pediatr Infect Dis J 1990; 9 (7): 488-94
3. Bijlmer HA, van Alphen L, Greenwood BM, et al. The epide-
miology of Haemophilus influenzae meningitis in children
under five years of age in The Gambia, West Africa. J Infect
Dis 1990; 161 (6): 1210-5
The estimates from this analysis provide a basis
for decision-makers to assess the value of immuni-
sation against Hib meningitis in Manila, Philippines.
As the baseline estimates applied in this analysis
were conservative, it appears that immunisation
against Hib would be a good investment from the
perspective of both the government and society.
If a vaccination programme against Hib men-
ingitis was introduced in Manila, 553 of the 980
cases per year from a birth cohort of 100 000 could
be prevented at a cost of PHP56 200 per case for
the 100 000 birth cohort. The net savings to gov-
ernment could be at least PHP39 million, and the
savings to society at least PHP225 million based
on a 90% efficacy rate, 95 per 100 000 incidence
rate, 85% vaccination coverage and 5% discount-
ing.
In the absence of other government projects with
a higher benefit to cost result, the Philippine gov-
ernment should consider including Hib conjugate
vaccine in its immunisation programme, since mon-
etary benefits of such a programme well exceed the
cost. However, although society could well afford
to pay PHP1166 per dose (break-even price) of the
vaccine, it is highly unlikely that the government
would be willing to pay this high price. If the Phil-
ippine government can successfully negotiate a price
equivalent to the hepatitis B vaccine negotiated price
of PHP20 in the Philippines,[49] then the benefit of
implementing a vaccination programme would ex-
ceed costs to government by at least PHP220 mil-
lion. Because the epidemiology and costs associ-
ated with Hib meningitis vary between countries,
the generalisability of the results of this study is
limited.
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duced. The results provide important information
for the decision-making process.
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Correspondence and offprints: M. Rhona M.T. Limcangco,
Pharmacy Practice and Science, School of Pharmacy, Uni-
versity of Maryland, Baltimore, 100 North Greene, Balti-
more, MD, 21201, USA.
E-mail: rlimc001@umaryland.edu
© Adis International Limited. All rights reserved.
Pharmacoeconomics 2001; 19 (4)