Mode of transmission:
Genomic succession investigation of COVID-19 gives the evidence that
about 88% similarities with 2 bat-derived (SARS) coronaviruses,
signifying that the mammals are the for the most part have probable
association flanked by COVID-19 with humans. Numerous reports have
recommended that the transmission which is causative for spreading this
infection is person-to-person transmission Mi, B et al (2020). This mode
of transmission as Person-to-person transmission appears to be occurred
mainly by means of the direct contact or may be all the way through the
droplets spread by sneezing and coughing as of the infected person. But
there is no transmission of the virus between mother and child either
through placenta or via lactation in pregnant or lactating mothers. This
is significant as the pregnant mothers are comparatively supplementary
vulnerable to infection by means of pathogens of respiratory tract type
of along with severe pneumonia Onder, G et al (2020). The infectious
diseases can be transmitted from animal to the human and then further
human to human transmission is also occurs. This transmission could be
direct or indirect tin nature Yang, G et al (2020). But for SARS-COV2 we
can explain this transmission is from animals to human (zoonotic) in
nature due to the evaluation of the people working in animal market in
Wuhan, China from where it actually spread Wu, Z et al (2020). The
researchers are trying to find the reservoir host or the intermediate
carrier which is actually the cause of spread to human. But, to date, we
are unable to find the reservoirs other than mammals along with those of
birds Jiang, F et al (2020).The binding of the receptor uttered through
the cells of the host is the foremost step of this infection subsequent
to union through cell membrane. It is consistent that the epithelial
cells of the lungs are considered to be the target as of virus Huang, X
et al (2020). Therefore, it has been reported that the person- to-
person transmissions as of the SARS-CoV mainly appears to be occur
through the binding of spikes of the virus with receptors of the cell as
(ACE2) angiotensin-converting enzyme 2
Jin, X et al (2020). Significantly, the succession of the
receptor-binding COVID-19 domain related in the direction of the
SARS-CoV. It also give the suggestion that entry and survival in the
cell is via ACE2 receptors which facilitates its binding and also
protect from harsh internal environment of body. And thus help in its
survival in the body Mo, P et al (2020).