BOOKS OF RtfiDIfGS - PAHO/WHO

- 96 -
RABIES CONTROL IN URBAN COLOMBIA
TABLE 1.
C'onpuiter Sinudlaion Experiotnems: Comiparison of four wa¢cinaslion policies, orer a ten-.eur period.
ita h rcgtrI tll s tllo' s¿ntil l l.¿tllt ti'¢' ,Ii lhl' r (If rlifld dogsx. th', flteel rct .luit*l' r of cci rsted dt>gs. oi¿d
¡he cosi vj ¡he inditiduúal policies.
Cost (dollars)
Number oí Mcan
Cl)idenilli toh l Iper ra.bid
trials per rabid Total dogs per dog jdog
Vaccinatiun policy experiment dogs vaccinated Total' vaccinated prevented
No vaccinaitioi
70%' initial vacciniation
1¡00 21.588 O 0 0 0
(entire city)"
70% iniiíal vaccination
70{P, ftvaccinatioin (yr. 5)
100 18.603 59.323 22.157 0.37 7.42
(;sir¢ ciíy)~'
'referrcd Vaccin:aiun
ISC 7.71 I 139,638 60.8 , 0.8.,1 .1.3.1
Policy (VA- 70%')'** 10 3,197 100.282 64.982 0.65 3.53
'lic os( of vacciniation is annually increased by an inflation factor of 5 percent
·* Thie simuliated camupaign took 85 days and required thlc use of 8 trucks and 48 vacem-lt;ors.
*'· The initial simulated campaign took 85 days and the second simulated campaign. due to
the canine population growth, took 112 days. Both campaigns required the use of 8 trucks and
4S vaccinators.
'' The policy ;cquired the continuous usc of I truck and 2 vaccinalors.
Rabies Control Center, and the unit cost of the vaccine, the 70 percent vaccination
campaign theoretically cost the administration 22,157 dollars. The cost per prevented
rabid dog is calculated for the len-ycar time period as 22,157 dollars divided by 2.985
prevented rabid dogs or 7.42 dollars per prevented rabid dog. The question lhen
arises, '"Can the health system manager do better with a different vaccination policy?"
3b. Two 70 Percent Vaccination Camnpaigns
It appears obvious that a second 70 percent vaccination campaign at year 5 would
be very beneficial. Figure 3 compares a policy of one initial 70 percent campaign
versus a policy of two 70 percent campaigns, one initial and one at year 5. The double
campaign reduces rabies for about nine years before there is an epidemic.
The cuos of the double camrpaign. as seen in Table 1, is almost triple the cost of the
single campaign due to the increase in both the city's canine population and thc cost
of labor, supplics, etc. associated with 'a five percení' annual inflation rate. The
cost-per-rabid dog prevented. however, is greatly decreased due to the sizable reduction
in the mean cumulative number of rabid dogs.
3c. Preferred Vaccinaoion Policy
In order to reduce further the incidence of rabies, we developed an alternative
policy which continuously employs throughout the planning horizon two vaccinators
traveling in one truck to various selected barrios. We refer to this control policy as the
Preferred Vaccination Policy since wc felt i. was the hest among all tested policies. A
formitiil for the Prefcrred Vaccination Policy was developed which ranks each barrio
accorditng Lo thc potenti[il conuilibution it would miake to ¡Ihe inicidence of c;nine
rabies. The risk of contributing to new rabies cases is calculated for each barrio as
follows:
j-_