  Recent study reported that an aerosolised virus (COVID-19) can survive in the
air for a few hours. It is highly possible that people get infected with the
disease by breathing and contact with items contaminated by the aerosolised
virus. However, the aerosolised virus transmission and trajectories in various
meteorological environments remain unclear. This paper has investigated the
movement of aerosolised viruses from a high concentration source across a dense
urban area. The case study looks at the highly air polluted areas of London:
University College Hospital (UCH) and King Cross and St Pancras International
Station (KCSPI). We explored the spread and decay of COVID-19 released from the
hospital and railway stations with the prescribed meteorological conditions.
The study has three key findings: the primary result is that it is possible for
the virus to travel from meters up to hundred meters from the source location.
The secondary finding shows viruses released into the atmosphere from entry and
exit points at KCSPI remain trapped within a small radial distance of < 50m.
This strengthens the case for the use of face coverings to reduce the infection
rate. The final finding shows that there are different levels of risk at
various door locations for UCH, depending on which door is used there can be a
higher concentration of COVID-19. Although our results are based on London,
since the fundamental knowledge processes are the same, our study can be
further extended to other locations (especially the highly air polluted areas)
in the world.
