5. Discussion

in health expenditure in an epidemic year is 0.16% for the countries with the highest number of cases (Table 5). Although this result cannot be perfectly extrapolated to all the countries of the Americas, it could be interpreted as an upper bound for the size of the economic burden of

Figure 6 shows the normalized treatment cost14 and burden for each country. We can observe that while the Dominican Republic is the country with the highest number of DALY adjusted by population, it has the lowest cost per each DALY lost because of the disease. In contrast, Mexico has the highest cost per DALY lost, but the lowest number of DALY adjusted by population.

Finally, Table 6 exhibits the 2015 total economic cost per DALY adjusted for purchasing power parity (PPP). There appears to be high variance in the total treatment cost, with its ranges from \$1,157 in the case of the Dominican Republic to \$17,703 for Mexico. It is noteworthy that Mexico, in relative terms, always presents the highest treatment cost. This result is consistent whether we analyze the total treatment cost per patient, the share of total annual cost over the

Total ambulatory (%) 0.16 0.17 0.08 0.17 Total hospitalized (%) 0.00 0.01 0.04 0.01 Total cost (%) 0.16 0.18 0.12 0.18 Source: PAHO. 2015. Week 52. Martelli, et al. (2015) [19], Castro, et al. (2015) [18], Undurraga, et al. (2014) [17], Shepard,

Brazil Colombia The Dominican Republic Mexico

Figure 6. Normalized results. 2015. Source: PAHO. 2015. Week 52. Martelli, et al. (2015) [19], Castro, et al. (2015) [18],

Variable definition: level of current health expenditure expressed as a percentage of GDP. Estimates of current health expenditures include healthcare goods and services consumed during each year. This indicator does not include capital health expenditures such as buildings, machinery, innovation and technology and stocks of vaccines for emergency or

Undurraga, et al. (2014) [17], Shepard, et al. (2011) [20]. Prices 2017.

total health expenditure or the total treatment per DALY adjusted for PPP.

Table 5. Total annual treatment cost as share of the total health expenditure (2015).

dengue in the region.

32 Dengue Fever - a Resilient Threat in the Face of Innovation

et al. (2011) [20]. Prices 2017.

14

outbreaks.

According to the review made by Shepard [22], who estimate the burden at a global scale for the year 2013, Latin-American and the Caribbean regions exhibit the highest treatment cost per case. From this perspective, our review presents the burden of the disease for the most affected countries, in terms of reported cases, of the region with the most expensive treatment cost. The latter is particularly relevant if we considered the estimates of the share of total treatment cost over the total health expenditure presented because our results could be interpreted as an upper bound for relative economic burden of dengue.

As mentioned before, in this section, we will discuss how the total treatment cost and the burden change in 2017, which we consider to be an inter-epidemic year given the low number of cases relative to previous years (2010–2017) (Table 7).


Source: PAHO. 2017. Week 52. Martelli, et al. (2015) [19], Castro, et al. (2015) [18], Undurraga, et al. (2014) [17], Shepard, et al. (2011) [20]. Prices 2017.

Table 7. 2017 Economic and DALY lost per million inhabitants by country (2017 dollars).

To estimate the total number of DALY for the year 2017, we calculated the ratio between dengue cases and DALY for 2015 with the WHO and PAHO figures and extrapolate the results as discussed in section "Materials and methods." Population has been updated too, to correspond to the year 2017. DALY adjusted for population present a dramatic decline of 76.53% in average due to the decrease in total number of dengue cases. Additionally, the total treatment cost of the disease decreased 77.8% in average (from 2015 to 2017), being Dominica Republic the country with the highest reduction rate (92.8%). It is worth saying that the change in the figures is closely tied to the change in the number of dengue cases since the cost per patient remained the same (Table 8).<sup>15</sup>

Normalized results for 2017 show that, in contrast to 2015, the Dominican Republic exhibits both the lowest total treatment cost per DALY and DALY per million of inhabitants, which suggest an improvement for the Caribbean country, especially considering the noneconomic burden. On the other hand, Mexico went from having the lowest number of DALY adjusted

The Burden of Dengue Illness and Its Economics Costs in the Americas: A Review on the Most Affected Countries

http://dx.doi.org/10.5772/intechopen.79887

35

One important limitation about this review and potentially other burden analyses is the accuracy of the epidemiological information. As the number of total dengue cases, severe and non-severe, corresponds to reported cases, one cannot assume that they correspond to the effective number of cases. Reported (or febrile) cases can overestimate the total actual burden of the disease. On the other hand, one should consider that by using laboratory confirmed cases, bias in the other direction is introduced, since not only that figure would be affected by laboratory confirmation policies and practices but also by underreport. After reviewing the latter, we decided to use reported cases and allow for potential overestimation in the economic burden. Thus, our results should be considered as upper bound estimates of the economic

The results found have three interesting implications for further studies and reviews. Economic burden of dengue should follow a structured costing framing, which allows for proper comparison between results and better estimation of treatment cost per case. The data and sources used in this chapter could serve as inputs in future cost-effectiveness analysis (CEA); once economic cost per cases has been covered, the remaining element to conduct a CEA would be the approximate reduction in dengue cases due to the use of a prevention technology. Finally, the similar results in terms of relative economic burden suggest that 0.16%<sup>17</sup> could be interpreted as an upper bound of the total treatment cost of dengue as share of total health expenditure.

Raúl Castro Rodríguez\*, Jorge Armando Rueda-Gallardo and Manuel Felipe Avella-Niño

[1] Martín J, Brathwaite O, Zambrano B, Solórzano J, Bouckenooghe A, Dayan G, Guzman M. The Epidemiology of Dengue in the Americas over the last Three Decades: a Worrisome Reality. The American Journal of Tropical Medicine and Hygiene. 2010;82(1):128-135

170.16% is the mean share for the four countries reviewed during a period of high incidence in the region with the most

Department of Economics, Universidad de los Andes, Bogotá D.C., Colombia

16Burden measured as DALY is not affected by overestimation since WHO figures are used.

for population to having one of the highest.

burden<sup>16</sup> and not completely accurate figures.

\*Address all correspondence to: rcastro@uniandes.edu.co

Author details

References

expensive treatment cost per case.

As result of the decline in the number dengue cases in 2017, the share of the total costs decreased to almost a fifth of the share in 2015 (Figure 7).


Source: PAHO. 2017. Week 52. Martelli, et al. (2015) [19], Castro, et al. (2015) [18], Undurraga, et al. (2014) [17], Shepard, et al. (2011) [20]. Prices 2017.

Table 8. Total health expenditure and 2017 total economic cost as share of the total health expenditure (2017 dollars).

Figure 7. Normalized results. 2017. Source: PAHO. 2017. Week 52. Martelli, et al. (2015) [19], Castro, et al. (2015) [18], Undurraga, et al. (2014) [17], Shepard, et al. (2011) [20]. Prices 2017.

<sup>15</sup>Cost per patient do not vary since they are expressed in 2017 dollar are correspond to the figures obtained in the respective studies reviewed.

Normalized results for 2017 show that, in contrast to 2015, the Dominican Republic exhibits both the lowest total treatment cost per DALY and DALY per million of inhabitants, which suggest an improvement for the Caribbean country, especially considering the noneconomic burden. On the other hand, Mexico went from having the lowest number of DALY adjusted for population to having one of the highest.

One important limitation about this review and potentially other burden analyses is the accuracy of the epidemiological information. As the number of total dengue cases, severe and non-severe, corresponds to reported cases, one cannot assume that they correspond to the effective number of cases. Reported (or febrile) cases can overestimate the total actual burden of the disease. On the other hand, one should consider that by using laboratory confirmed cases, bias in the other direction is introduced, since not only that figure would be affected by laboratory confirmation policies and practices but also by underreport. After reviewing the latter, we decided to use reported cases and allow for potential overestimation in the economic burden. Thus, our results should be considered as upper bound estimates of the economic burden<sup>16</sup> and not completely accurate figures.

The results found have three interesting implications for further studies and reviews. Economic burden of dengue should follow a structured costing framing, which allows for proper comparison between results and better estimation of treatment cost per case. The data and sources used in this chapter could serve as inputs in future cost-effectiveness analysis (CEA); once economic cost per cases has been covered, the remaining element to conduct a CEA would be the approximate reduction in dengue cases due to the use of a prevention technology. Finally, the similar results in terms of relative economic burden suggest that 0.16%<sup>17</sup> could be interpreted as an upper bound of the total treatment cost of dengue as share of total health expenditure.
