<p>The world is facing several threats of viral infections, which are causing serious concerns to human health. One such virus infection, Human Metapneumovirus (hMPV), is discussed in this article with the help of Mathematical modeling. We have developed a new mathematical model for hMPV with five dependent variables: the susceptible, susceptible under age 5 and above age 65, infected, virus load, and recovered population. The model comprises different parameters such as increasing recruitment rate, rate of immunity, rate of precautions, and decreasing the rate of interaction between susceptible &amp; infected populations. This model helps analyze and study five subpopulations that help prevent and control viral-infected diseases. The presented equations are studied with the help of the Legendre wavelet collocation method (LWCM) using the Legendre operational matrix of integration and collocation method. The results obtained from LWCM are compared with those obtained using the RK4 method, and NDSolver is used to compare the nature and solution of the presented mathematical model. The absolute error of LWCM almost converges to Zero when compared to RK4. We have also studied the variation of parameters to show how the nature of differential equations varies. The Mathematica software has been used for numerical computations.</p>