Marwan Osman, PhD, DABMM, MPH

Infectious diseases and antimicrobial resistance (AMR) are serious concerns that can severely impact both developed and developing countries across the globe. However, underprivileged populations and low- and middle-income countries (LMICs) face elevated risks due to limited access to medical care, sanitation, and safe food. While numerous countries have initiated action plans to deal with these challenges, most LMICs are critically lagging behind. These challenges are exacerbated further by catastrophic events like war and mass displacements, which strain healthcare systems and spur the emergence of microbial infections and AMR, increasing mortality and morbidity. Of particular concern is the emergence of multidrug-resistant pathogens in these populations and settings. Furthermore, AMR has ramifications internationally because resistance can easily spill over across national borders.

To address this global challenge, I have extensively conducted large-scale One Health investigations using both conventional and next-generation sequencing analyses in Lebanon and the United States to study the epidemiology of infectious diseases, assess antimicrobial resistance phenotypes, and identify genetic resistance determinants of bacteria and fungi of clinical interest in humans, animals, food, and the environment.

A prominent project that demonstrates my engagements in One Health is the nationwide evaluation of tuberculosis in collaboration with the Lebanese Ministry of Health and international stakeholders. In this project, we have identified the first cases of extensively drug-resistant (XDR) tuberculosis isolated from refugees and migrants in Lebanon. That has led to the establishment of new policies for sustainable diagnosis of drug-resistant tuberculosis to control and prevent the spread of this disease and improve patient outcomes in the country and in displaced communities. Another example is our project that tackles colistin resistance, a phenomenon that has raised alarming concerns and has posed a threat to global public health. We identified mobile colistin resistance (mcr) gene variants in the human-animal-environment nexus, particularly in poultry farms. Notably, mcr can be transmitted horizontally on plasmids and has been spreading worldwide. These findings have supported Lebanon’s recent ban (Resolution No. 221/1) on the use of colistin for agricultural purposes, making it one of the first laws of its kind to take effect in the country and the Middle East region. We recently hypothesized and proved that these genes are also spreading in the United States.

In conclusion, we have identified critical threats in LMICs and their potential spread to other countries. Our research provides science-based information for the international community to address the severe problem of the proliferation of AMR. It also shows that Integrated surveillance programs are urgently and strategically required in low-resource countries to prevent the spread of infectious diseases and mitigate the growing threat of AMR on a global scale.