Acute bronchiolitis is the most important cause of lower respiratory tract infection in children during the first two years of life and is the leading cause of hospitalization for infants beyond the neonatal period.1 Respiratory syncytial virus (RSV) is the most commonly identified virus, being responsible for approximately 60% of bronchiolitis cases.2–4 Recent reports have shown that RSV-related infection is an important cause of death in children in younger children, especially in those with comorbidities.5

The disease places a large economic burden, not only on healthcare systems, but also on families and society as a whole,6 mainly in middle-income countries (MICs).7 Recent studies reporting an increase in the rate of hospitalization over the last decades point to the growing resource utilization, costs and public health burden of the disease.8 The substantial clinical and economic burden of RSV-related bronchiolitis hospitalizations justifies continuing efforts that have been made to prevent or attenuate the RSV disease both through active and passive immunizations especially among high-risk infants.9

Understanding the costs associated with the management of RSV-related bronchiolitis hospitalizations is essential in terms of public policy considerations for deciding on resource allocation and setting priorities for child health. Recent reports have suggested that perinatal immunization strategies for children aged younger than six months could have a substantial impact on RSV-related child mortality in MICs.5 However, the RSV immunoprophylaxis is costly, and its cost-effectiveness has been demonstrated only in selected high-risk group of infants.10,11 Currently, a phase 3 clinical trial is ongoing to determine the efficacy of a RSV vaccine for infants via maternal immunization, with objective measures of medical significance of lower respiratory tract infection from 90 to 180 days of life in infants.12 Accordingly, there is a critical need for studies that provide accurate information on hospital costs for treating RSV-related bronchiolitis. The latter is essential for making informed decisions on resource allocation and for providing an input into price negotiations for current and newer RSV vaccines, and consequently to help to ensure the most efficient use of health resources, especially in MICs, where these resources are always scarce. However, despite its importance, a literature review reveals a scarcity of published data regarding hospital costs for treating RSV infections in MICs. Although several studies in high-income countries have reported the costs associated with episodes of bronchiolitis, only little knowledge exists about treatment costs in MICs.

The aim of the present study was to evaluate the direct medical costs associated with bronchiolitis hospitalizations caused by infection with RSV among infants under two years of age residing in Bogota, Colombia, a tropical MIC located in South America.

The present study shows that bronchiolitis hospitalizations caused by infection with RSV among infants younger than two years of age place a significant economic burden on the Colombian healthcare system. Additionally, that the in-patient care costs of infants treated in the PIMC or in the PICU were approximately 5.0–2.5 times greater than those for infants treated in the PW, and that in general, the more severely ill the patient, the greater the percentage of the bill attributable to hotel services (hospital stay), fluids and supplies, and medications, and the lesser the percentage of the bill attributable to medical services and nebulization and oxygen therapy.

The most remarkable result to emerge from the data is that it further enhances the understanding of the impact of RSV by estimating the economic burden of RSV-related bronchiolitis hospitalizations in a middle-income tropical country. This is essential for an accurate assessment of cost-effectiveness studies of current and future interventions for preventing or treating these respiratory infections. Specifically, although not exclusively, our results could serve as an input for models for assessing the cost-effectiveness of both RSV-specific humanized immunoglobulin (palivizumab) and the future RSV vaccines for infants via maternal immunization.12

Our results agree with those reported by Heikkila P. et al., showing a higher proportion of hospital costs driven by the cost of infants aged less than 12 months and by those treated in the PICU in contrast to infants aged more than 12 months and to other inpatients.15 Likewise, our results are in good agreement with those obtained in other recent studies performed in second and third healthcare level hospitals in our country in which it has been reported both that the mean direct cost of infants with bronchiolitis ranged between US$492.0 and US$1492.0, and that the mean LOS was 6.2 (± 0.51 days).16,17 Similarly, in agreement with our findings, studies in the literature have reported proportions of costs in infants requiring admission to the PICU with respect to infants treated in general wards ranging from 1.5 to 4.0, with the greatest proportions among infants aged less than 12 months.15,18 However, we found much lower costs for RSV-related bronchiolitis hospitalizations with respect to those reported in more affluent countries, with these differences being more apparent when studies conducted in the United States were used for comparison.9,15,18–22 The reported mean costs of RSV-related bronchiolitis hospitalizations vary extensively between studies performed in United States, Canada and in the UK, ranging between US$1313.2 and US$50853.0, after conversion into dollars based on official exchange rates. Notably, the observed differences in costs for RSV-related bronchiolitis hospitalizations are present despite a longer mean LOS in our patients, a variable that has been reported as an important determinant of the cost of bronchiolitis hospitalizations.15 The observed differences in costs of RSV-related bronchiolitis hospitalizations between countries likely result from many factors. It has been well described in the literature that variations in healthcare costs between countries with various types of health care systems may be due to several causes, such as the prices of labor, services and goods, including pharmaceuticals, volume of resources, administrative costs, use of high-tech interventions, access to and provision of specialized care instead of primary care, and payment schemes.23,24 Of these, prices of labor and goods, including pharmaceuticals, and administrative costs appeared to be the major drivers of the variation in costs between countries, especially between the United States and other countries.24,25 Our results corroborate the expected international cost differences in hospitalization costs from RSV-related bronchiolitis, and highlight the importance of their accurate estimation in different countries in order to help to allow just allocation of resources within the health care systems of each of these countries.

We are aware that our research may have at least four limitations. The first is that the study took only direct medical costs into consideration. The second is that the study focused only on costs associated with hospitalizations and did not include costs arising before admission or after discharge from hospital, including the subsequent morbidity after RSV infection. Although in-patient care accounts for a high proportion of the total costs of bronchiolitis,15 the exclusion of indirect costs and costs arising after discharge from hospital, could have underestimated the actual costs associated with RSV-related bronchiolitis. The third is that our study was limited to patients hospitalized at a single tertiary care pediatric hospital and our findings could not be generalizable to all bronchiolitis patients. However, the Fundacion Hospital La Misericordia receives patients from the majority and most representative medical insurance companies in the city and the country. The fourth is our inability to calculate marginal increased costs resulting from patients’ moving through hospital services of increasing complexity.

These limitations warrant further research in other hospitals and to take into consideration not only indirect costs, but also the long-term consequences of RSV-bronchiolitis, which in approximately half of the cases comprises recurrent wheezing/asthma symptoms.26 Recurrent wheezing/asthma episodes are responsible for significant use of quick relievers and controller medications and for substantial use of health care resources such as urgent care, emergency department visits, and hospitalizations.27,28 In addition, it is worth mentioning that prophylactic administration of palivizumab has been reported as reducing the risk of recurrent wheezing and asthma.29,30

In conclusion, the present study helps to further our understanding of the economic burden of RSV-related bronchiolitis hospitalizations among infants younger than two years of age in a middle-income tropical country. This is essential for assessment of the cost-effectiveness of interventions to help to ensure the most efficient use of health resources within the Colombian healthcare system and probably that of other similar MICs. Future studies should consider not only the direct medical costs associated with bronchiolitis hospitalizations caused by infection with RSV, but also indirect costs and costs associated with the long-term consequences of RSV-bronchiolitis.

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

None.