The cost-effectiveness of the use of selective media for the diagnosis of melioidosis in different settings

Background: Melioidosis is a frequently fatal disease requiring specific treatment. The yield of Burkholderia pseudomallei from sites with a normal flora is increased by culture using selective, differential media such as Ashdown’s agar and selective broth. However, since melioidosis mainly affects people in resource-poor countries, the cost effectiveness of selective culture has been questioned. We therefore retrospectively evaluated this in two laboratories in southeast Asia. Methodology/Principal findings: The results of all cultures in the microbiology laboratories of Mahosot Hospital, Vientiane, Laos and Angkor Hospital for Children, Siem Reap, Cambodia, in 2017 were reviewed. We identified patients with melioidosis who were only diagnosed as a result of culture of non-sterile sites and established the total number of such samples cultured using selective media and the associated costs in each laboratory. We then conducted a rudimentary cost-effectiveness analysis by determining the incremental cost-effectiveness ratio (ICER) per DALY averted and compared this against the 2017 GDP per capita in each country. Conclusions/Significance: Selective culture for B. pseudomallei should be considered by all laboratories in melioidosis-endemic areas. However, the appropriate strategy for implementation should be decided locally. Author summary: Melioidosis is a frequently fatal disease caused by a soil bacterium called Burkholderia pseudomallei, that is widespread in the rural tropics. Because staff are often not familiar with it and because it may be hidden if it is outgrown by other bacteria, special culture media can help laboratories diagnose the disease. However, this costs more money so it is not always done even in areas where the disease is known to be present. We have looked at the results of a year’s bacterial cultures in two different laboratories in southeast Asia to identify how many patients were only identified using these special culture techniques, how much it cost, and whether the investment was considered worthwhile in terms of the gain in healthy life years in these patients who might otherwise have died had the disease not been diagnosed. Even though the laboratories adopted very different strategies for using the special media and served very different populations, in both places the use of the special techniques was very cost effective in terms not just of lives saved, but on purely financial grounds when compared with the GDP of each country.