As we are all aware most of theMicrobial growth kinetics follows four stages namely ,which are the subject of my mathematical analysis . 1. LAG PHASE 2. LOG PHASE ( EXPONENTIAL PHASE ) 3. STATIC or STATIONARY PHASE 4. DECLINING PHASE. Under this present pandemic situation of Covid19 - A Virulent microbes where exponential phase is much higer and Uncontrollable . only prolonged lockdown period will make the sharp exponential phase to flat one . The mathematical modelling equations are developed to combine the mathematical model for a Pseudo – Gaussian distribution curve – for Growth of Covid19 . The superimposition of Gaussiun curve with Microbial growth curve can be fitted for the resulant model equation considering the sharp Exponential spreading of the VirusIn this hypothesis we will analyse the Linear combination of atomic orbital ( LCAO ) to overlap s -Orbital and p-Orbital to give rise to a hybrid Sp orbital having 50 % s and 50 % p – Character .Like s –Orbital – spherically symmetrical like Covid19 geometry & Remedesivir the most potent Synthetic -antiviral may be assumed to dumble shaped p-Orbital in geometry . Here Covid –Remedesivir drug – protein ( DP ) intermediate may be considered Sp hybridisation analogous to Molecular Orbital theory . The following logic of Atomic theory can be correlated to Covid19 asfollows : .In this approach we will summarisethe the last three publicationshighlighting the key mathematical approach like Exponential F ( x ) to further exponential –Gaussian F ( x ) and finally the Linear Combination of Atomic Orbital ( LCAO ) ie a hybridised Sp orbital overlapping to Remdesivir ( Drug ) –Covid19 approach.