Abstract
COVID-19 pandemic has started in December 2019 in China and quickly
extended to become a worldwide health and economic emergency issue. It
is caused by the novel coronavirus; SARS-CoV-2. COVID-19 patients’
clinical presentations vary from asymptomatic infection or flu like
symptoms to serious pneumonia which could be associated with multiple
organ failure possibly leading to death. It is understood that the
immune response to SARS-CoV-2 includes all elements of the immune system
which could altogether succeed in viral elimination and complete cure.
Meanwhile, this immune response may also lead to progression of disease
and could be responsible for the patient’s death. Many trials have been
done recently to create therapies and vaccines against human coronavirus
infections such as MERS or SARS, however, till now, no effective
antiviral drugs or vaccines have been approved to treat or prevent this
disease and its management depends mainly on supportive care. The spike
glycoprotein or protein S of SARS-CoV-2 is the main promoter that
induces development of neutralizing antibodies; hence, many attempts of
vaccines and antiviral drugs development have been designed to be
directed specifically against this protein. While some of these attempts
have been proved to be efficient in in vitro settings, only few of them
have been proceeded to randomized animal trials and human studies which
makes Covid-19 prevention an ongoing challenge. This review describes
the natural immune response scenario during COVID-19 and the vaccines
development trials to create efficient vaccines thus helping to build
more effective approaches for prophylaxis and management.