Candida Surveillance Pilot Findings

> Research explainer: This briefing examines verified primary research published 69 days before the briefing date. It is not a same-day research update and does not provide medical advice.

Evidence

This research explainer examines a WHO GLASS-Fungi multicentre observational demonstration study of laboratory-confirmed Candida bloodstream infections. Fourteen laboratories in 13 countries contributed data from 301 surveillance sites and 3,447 patients with candidemia. The surveillance data covered January 2017 through July 2021 and were collected using a standardized protocol and WHONET software. Participating sites were trained to collect, deduplicate, and report clinical and microbiological data.

The species distribution differed across the participating settings. Candida albicans was the predominant species overall, accounting for 37.6% of reported cases (95% CI 33.8–41.5%). It was most common in the Americas, Europe, and Africa in this dataset. Candida tropicalis was more prevalent in Southeast Asia than in the other described participating regions. Candida auris was detected by two laboratories, one in Southeast Asia and one in Africa.

The resistance findings have a deliberately narrower denominator than all reported infections. Among isolates with interpretable antifungal susceptibility-testing results and corresponding established breakpoints, 13.6% were resistant to at least one antifungal agent (95% CI 10.1–17.2%). Fluconazole resistance was highest among Candida parapsilosis isolates, at 29.7% (95% CI 18.2–41.2%). These figures describe the pilot’s tested, interpretable isolates; they do not establish a resistance rate for all Candida bloodstream infections in the participating countries or globally.

The implementation record is also evidence. Sites reported that standardized tools and procedures could be used to collect and report fungal antimicrobial-resistance surveillance data. At the same time, the pilot identified obstacles in data extraction, conversion, upload, and sharing agreements. Limited fungal laboratory capacity, restricted access to susceptibility testing, and lack of sustained funding were reported as barriers, particularly in low- and middle-income countries.

Analysis — Surveillance feasibility and interpretation

The central contribution of this study is operational rather than epidemiologic certainty. It demonstrates that a standardized GLASS workflow can generate comparable descriptive Candida bloodstream-infection data across participating laboratories, including species distribution and susceptibility information. That matters because the pilot links clinical and microbiological reporting procedures rather than relying solely on disconnected local summaries. Its findings make the surveillance gaps visible: producing a resistance estimate requires laboratory testing, interpretable results, recognized breakpoints, data systems, and an ability to share records. A missing link at any stage can remove settings or isolates from the resulting picture.

The regional species patterns and resistance percentages are therefore best read as pilot outputs that help define what a broader surveillance system would need to measure. The contrast between overall predominance of C. albicans, greater prevalence of C. tropicalis in Southeast Asia, and detection of C. auris at two laboratories illustrates why species-level reporting can be informative within a standardized framework. Similarly, the 13.6% estimate is informative about the subset meeting the study’s susceptibility criteria, while its stated denominator prevents it from being treated as a universal prevalence measure.

The study also frames infrastructure as part of the evidence problem. Sites with fungal laboratory expertise were able to participate, yet they still described capacity, extraction, sharing, and funding constraints. This means expansion is not simply a matter of asking more sites to submit data. The pilot supports the feasibility of the approach in participating settings and identifies the practical conditions that shape whether more representative reporting can occur. It does not show that those conditions already exist across countries, nor does it establish trends, causes of resistance, comparative clinical outcomes, or treatment effects.

Limitations

This was a multicentre observational demonstration study, not a population-representative survey. The authors state that analyses were descriptive and were not designed for causal inference or population-level generalization. Participating sites were not necessarily representative and included settings with existing fungal laboratory expertise, so their results cannot be assumed to characterize countries, regions, or the world.

The underlying infections were recorded from January 2017 to July 2021, not in 2026. Susceptibility findings apply only to isolates with interpretable results and established breakpoints; incomplete access to testing can affect which isolates contribute. The study reports laboratory-confirmed bloodstream infections, so it does not quantify all invasive fungal disease. Finally, reported implementation barriers may themselves limit data completeness and comparability as surveillance expands.