Obligate intracellular bacteria: From bench to field and bedside

Dr. Marie Buysse earned her PhD in 2022 from the University of Montpellier, where she studied heritable endosymbiotic systems—both obligate and facultative—in ticks. Her research focuses on the mechanisms that sustain tick–microbe associations, their evolutionary dynamics, and the influence of microbial communities on tick biology and vector competence. She is currently based at the MIVEGEC research unit in Montpellier as a CNRS affiliated postdoc, where she continues to investigate host–microbe interactions, now broadening her work to include two additional key factors: wild animal hosts and human-impacted environments. Through an interdisciplinary approach combining fieldwork, laboratory experiments, and bioinformatics, her work aims to better understand the ecological and evolutionary forces shaping tick-associated microbiomes.

Dr. Zubaidah Ya’cob is a Senior Lecturer at the Tropical Infectious Diseases Research & Education Centre (TIDREC), Universiti Malaya, and an entomologist specializing in public health arthropods that transmit vector-borne bacterial pathogens. Her research focuses on disease vectors such as ticks, chiggers, sandflies, and blackflies, with particular emphasis on their biology, ecology, and roles in the transmission of pathogens responsible for scrub typhus, rickettsioses, onchocerciasis, and leishmaniasis. Dr. Zubaidah’s work has generated significant insights into vector-pathogen interactions and transmission mechanisms, supporting more effective public health strategies for disease control and prevention. Her scholarly contributions are reflected in a growing portfolio of peer-reviewed publications and national and international collaborative research projects.

Dr Aránzazu Portillo is Responsible for the Special Pathogens Laboratory-Centre of Rickettsioses and Arthropod-Borne Diseases (CRETAV), attached to the Infectious Diseases Department from San Pedro University Hospital-Centre for Biomedical Research of La Rioja, and located in Logroño (Spain). She was the person in charge of starting up this laboratory (CRETAV) from its beginnings in 2002. Today, CRETAV includes a biosafety level 3 facility and serves as one of the reference laboratories within the Spanish Network of Biological Alert Laboratories (RELAB), under the Ministry of Science.

Dr Portillo is focused on zoonoses research under a 'One Health' prism; specifically, on emerging/remerging pathogens and diseases transmitted by arthropods, such as rickettsiosis, Lyme borreliosis, bartonella infection, anaplasmosis or Crimean-Congo hemorrhagic fever (CCHF), among others. She leads the development of molecular, serologic and culture methods to support the diagnosis of these infections within a multidisciplinary workgroup. Her contributions in collaboration with other team members, range from the implication of novel bacteria as human pathogens (Rickettsia rioja, now called Rickettsia riojensis) to the first detection of emerging microorganisms in ticks in our country, including FHCC virus or Neoehrichia mikurensis, among others. Dr Portillo has participated in the description of new bacteria (e.g.: Rickettsia colombiensis, Rickettsia vini) and of large patient cohorts with tick-borne diseases, such as DEBONEL and Rickettsia sibirica mongolitimonae infection. She has contributed to characterize the microbiome of arthropods, and worked on the application of cutting-edge '-omic’ techniques to improve diagnosis accuracy. Involved in competitive research projects, consortia and networks, currently she is the principal investigator of a multicentric national project to assess the risk of suffering tick-borne diseases in urban areas across Spain.

With a global perspective on emerging health threats, she provides support from the research lab to assisting clinical activities, with improvements in the hospital environment related to prevention, diagnosis, and treatment of vector-borne diseases, primarily those transmitted by ticks, but also by fleas, trombiculid mites, lice, and others. Dr Portillo has coordinated and/or contributed to the development of national and international diagnostic guidelines, consensus documents, and co-authored the first and subsequent reports on FHCC risk for public health authorities. Beyond the hospital, she is actively involved in promoting health education through initiatives in schools, community associations, and health centers. Dr Portillo serves as a reviewer and editor for scientific journals, a evaluator of international, national and regional research proposals, and currently holds the position of President of the Chlamydia, Coxiella, Anaplasma, Rickettsia Study Group of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID). In addition to research, she has maintained an active teaching role at the University of La Rioja with longstanding commitment to training and mentoring students and research staff.