Diagnosis of bloodstream infections (BSI) is done by sampling blood in blood culture bottles that are checked for growth in the microbiology laboratory. In LRS, microbiology laboratories are however scarce, and BSI cannot be diagnosed, resulting in overuse of antibiotics which fuels AMR. For diagnosis of BSI, so-called manual blood culture (equipment-free) systems are used in LRS, with daily visual inspection for growth. Compared to automates, manual systems are less sensitive, and growth is slower; in addition, training and experience are needed before laboratory staff is competent to detect growth when inspecting the blood culture bottles.

A simplified blood culture system could enable expanded use of blood cultures in LRS and would thus improve BSI treatment. Ongoing research at the Institute of Tropical Medicine, in collaboration with Ghent University has resulted in a novel, simple, cheap, open-access and robust blood culture system, the Bactinsight blood culture system. This system consists of two modules. Firstly, a portable, battery-operated measurement device (turbidimeter), which monitors and detects bacterial growth in blood culture bottles based on the turbidity of the culture medium caused by bacterial growth. Secondly, optimized blood culture bottles have been developed. A second step in blood cultures is the identification of the causing organism. Researchers at LETI (Grenoble, France) have developed a lensfree microscope, which simplifies and expedites identification of the causative organisms, improving patient's diagnosis and more directed antibiotic treatment. The lensfree microscope is an additional module for the Bactinsight blood culture system.

In SIMBLE, the Bactinsight blood culture system will be evaluated against reference systems in two phases. During the optimization phase in Belgium, the performance of Bactinsight turbidimeter + lensfree microscope will be tested in a reference hospital laboratory. In parallel, an in vitro laboratory evaluation of the Bactinsight blood culture system (turbidimeter + blood culture bottles + lensfree microscope) will be done using spiked blood cultures. In the field-testing phase, the ease-of-use, acceptability, adoptability and performance of Bactinsight blood culture system will be evaluated in three hospitals in Benin and Burkina Faso. The blood culture bottles used for this study will be manufactured in a production facility in Benin, that will be installed at the start of the project.

Inclusion Criteria:

• With indications for blood culture sampling and for whom collection of a blood culture sample is part of standard clinical practice
• Willing and able to provide written informed consent (assent for minors)

Exclusion Criteria:

• none

Patients older then 15 years old presenting themselves with indications for blood culture sampling and for whom collection of a blood culture sample is part of standard clinical practice.