Micro and nanotechnology have enabled groundbreaking innovation to detect and predict different disease conditions and at the same time detect key analytes and microorganisms that have a profound impact on our health. This invited talk will start with the detection of Listeria monocytogenes, a food-borne pathogen that causes listeriosis, based on Mach Zehnder interferometry. This will be followed by demonstrating a miniaturization technique for ELISA on a micro-chip to detect vector-borne diseases such as Dengue NS1. Towards the fight for COVID-19, a sustainable technology based on a paper strip with conjugated nanoparticles and aptamers will be discussed. Equally important is access to clean water for healthy communities. In this direction, some of the innovative technologies developed in recent years for the rapid detection of E. coli in water will be discussed. Finally, a new technology, a dip-and-fold paper device for the detection of pesticides in water, will be demonstrated.