COVID-19 is a global pandemic resulting in devastating impacts that spread
through a virus and are even more contagious than influenza, as evident from the
frequent reporting of cluster outbreaks. Although the key problem is that the symptoms
are often similar to other common illnesses, such outbreaks can be controlled if
individuals with initial symptoms are tested, and further contact tracing is done. The
concept presented here discusses the order in which symptoms appear to differentiate it
from other respiratory disorders, however, this crucial information is mostly missing.
To determine the most likely order of detectable symptoms in COVID-19 patients, we
apply a Markov Process to a graded partially ordered set based on clinical observations
of COVID-19 cases. A comparison was made between the evolution of these symptoms
in COVID-19 and influenza, SARS, and MERS to see if they were present differently.
Influenza, according to our hypothesis, begins with a cough, whereas COVID-19 and
other coronavirus infections begin with a fever. COVID-19, on the other hand, varies
from SARS and MERS in terms of the order of gastrointestinal symptoms. As facilities
begin to reopen following the 2020 spring outbreak, our findings support the idea that
fever should be used to screen for admission and that appropriate clinical practice
should include noting the order of symptoms occurrence in COVID-19 along with
other diseases. If this type of systemic clinical approach had been routine, the move
from a local to a worldwide pandemic might not have happened.
Keywords: Clinical approach, COVID-19, Fever, Infections, Markov Process, MERS, Pandemic, SARS, Variants.