A new study introducing dry blood spot (DBS) and oral fluid (OF) sampling for suspected measles and rubella cases was launched in Sofia, Bulgaria, on 9 February 2026 by H.E. Mr Chikahisa Sumi, Ambassador of Japan to Bulgaria; Kristina Mauer-Stender, Special Representative of the WHO Regional Director in Bulgaria; and Professor Dr Iva Hristova, Director of the National Centre of Infectious and Parasitic Diseases (NCIPD).
Under the study, general practitioners in selected regions will collect paired DBS and OF samples from suspected cases – primarily children presenting with fever and rash – and the samples will be tested for measles and rubella antibodies and ribonucleic acid at the National Reference Laboratory for Measles, Mumps and Rubella at the NCIPD. These sampling methods are less invasive than venous blood sampling, and thereby more acceptable to parents, and can be conducted at a local clinic rather than a hospital. This is expected to increase the number of samples submitted for laboratory investigation and thereby strengthen measles and rubella surveillance. The study aims to assess the diagnostic performance, feasibility and acceptability in routine practice of this new sampling approach.
The initiative is implemented in partnership with NCIPD and the Ministry of Health of Bulgaria, with support from the Asia-Europe Foundation (ASEF) and Government of Japan. “We are doing this together,” said Kristina Mauer-Stender. “This new approach makes surveillance more accessible, more efficient and more responsive. Ultimately, the goal is to gather robust and reliable data to help inform public health interventions.”
Ongoing efforts to maintain measles and rubella elimination
Bulgaria has achieved both measles and rubella elimination, as verified by the European Regional Verification Commission for Measles and Rubella Elimination in its September 2025 meeting. Maintaining that status requires continued vigilance, timely case detection and laboratory investigation of every suspected case. In recent years, the number of samples from suspected measles or rubella cases in some regions of Bulgaria have been lower than expected, based on WHO indicators for maintaining measles and rubella elimination status. Strengthening sample collection in harder-to-reach areas, particularly rural communities, is therefore a key priority. “For us, this study is important because it supports the larger goal of sustaining the elimination of measles and rubella,” said Professor Dr Iva Hristova.
The study will inform future surveillance policy and help reinforce outbreak preparedness and response capacity. It also reflects a shared commitment by national authorities and partners to sustain elimination gains in Bulgaria and contribute to health security across the WHO European Region.
“Health is the foundation of people’s well-being,” said Ambassador Sumi. “Japan remains committed to working closely with WHO, ASEF and the Ministry of Health of Bulgaria to strengthen public health.”