Budget impact analysis of multiple varicella vaccination strategies: a Mexico perspective

Figures & data

Figure 1. Budget impact structure.

Table 1. Vaccine characteristics.

Vaccine	Initial efficacy	Duration of protection (years)
Highly effective (OKA strain)	95%	25
Moderately effective (OKA strain)	75%	5
Weakly effective (MAV/06 strain)	50%	1

Sources: highly effective vaccine,^23,27 moderately effective vaccine,^28,29 and weakly effective vaccine.^30,31

Table 2. Unit costs.

Resource	Unit costs (2015 MXN)^A	Sources and assumptions
Vaccine acquisition, cost per dose
Highly effective vaccine	321.00	Mexican Institute of Social Security (IMSS)^Citation33
Moderately effective vaccine	289.00	Assumed 10% less than the cost of the highly effective vaccine
Weakly effective vaccine	260.00	Assumed 10% less than the cost of the moderately effective vaccine
Administration costs per dose	18.77	Portnoy et al.^Citation34 Incremental cost of any of the three single-dose varicella vaccines administered at the same visit as the measles-mumps-rubella vaccine^B
Cost per outpatient visit for varicella	599.00	Unit costs catalog 2015^Citation35
Cost per prescription medication (for outpatient varicella case)	4.08	Mexican Institute of Social Security (IMSS)^Citation33 Cost data assumes the average cost of naproxen 250 mg (30 tablets) and diphenhydramine (60 mL)
Cost per bed day (for inpatient varicella case), by age group
< 1 years	6,054.77	Cost of hospitalization divided by average number of bed days per stay based on Mexican panel of experts^C
1–4 years	6,529.66
5–9 years	6,937.76
10–14 years	6,796.18
15–44 years	5,741.60
45–64 years	5,123.27
≥65 years	4,757.32
Cost per herpes zoster case, by severity
Without postherpetic neuralgia	5,235.33	Rampakakis et al.^Citation36
With postherpetic neuralgia	11,290.06

^AWhere necessary, costs were converted and/or adjusted to 2015 MXN using the web-based tool CCEMG – EPPI-Center Cost Converter.³⁷

^BCost of vaccine wastage was excluded because a single-dose vial was assumed to be used.

^CAverage number of bed days per stay based on Mexican panel of experts (Merck & Co., Inc; unpublished). Detailed data shown in Supplemental Table 1.

Table 3. Health outcome and direct medical costs for 3 vaccination scenarios in year 1^A.

	Varicella outcomes and costs				Budget impact
	No vaccination	Highly effective	Moderately effective	Weakly effective	Highly effective	Moderately effective	Weakly effective
Varicella cases	2,010,002	1,592,234	1,627,378	1,677,143	−417,768	−382,624	−332,859
Varicella deaths	283	227	230	235	−56	−53	−48
Total annual costs ^B	4,977,538,459	4,416,333,877	4,461,552,395	4,550,194,779	−561,204,582	−515,986,064	−427,343,680
Vaccine acquisition	0	471,721,386	424,450,951	381,553,255	471,721,386	424,450,951	381,553,255
Vaccine administration	0	27,582,782	27,566,853	27,544,782	27,582,782	27,566,853	27,544,782
Varicella treatment	4,977,538,459	3,917,029,709	4,009,534,591	4,141,096,742	−1,060,508,749	−968,003,868	−836,441,717
Varicella treatment costs, by visit type ^B
Inpatient costs	4,239,721,087	3,332,168,753	3,411,993,657	3,525,544,845	−907,552,334	−827,727,431	−714,176,243
Outpatient costs	737,817,372	584,860,956	597,540,934	615,551,897	−152,956,416	−140,276,437	−122,265,474

^A For 3 vaccine types (highly, moderately, and weakly effective) at 95% coverage.

^B All costs are presented in undiscounted 2015 MXN.

Figure 2. Total varicella cases per year, by vaccine type and percent coverage.

Figure 3. Total costs per year, by vaccine type and percent coverage.

Figure 4. Budget impact of varicella vaccine per year, by vaccine type and percent coverage.

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