Introduction
Coronaviruses are a large family of viruses discovered in 1960 that can
cause the common cold. Coronavirus disease 2019 (COVID-19), induced by
the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was
first reported in December 2019, and the number of affected countries
grew rapidly, prompting the World Health Organization to disclose it as
a pandemic in 2020. Almost all of the COVID-19 patient populations are
clinically silent or have mild to severe respiratory illness. However,
death cases involving sub and systemic manifestations such as sepsis,
septic shock, and multiple organ dysfunction syndromes (MODS) have been
reported. (1)
The pandemic had caused more than 629 million cases and 6.58 million
confirmed deaths as of October 27, 2022, helping to make it one of the
toughest in history. (2)
From 3 January 2020 to 5:43 pm CEST on 28 October 2022, there were
2,461,107 known cases of COVID-19 in Iraq, with 25,358 fatalities,
according to WHO data. A total of more 19,394,050 vaccine doses has been
delivered as of Oct 22, 2022. (3)
The cytokine storm is critical in the pathophysiology of severe COVID-19
patients. (4)
Cytokine storms can also be caused by a variety of viral and especially
non-disorders, and they can cause serious damage to several organs. (5)
The apparent long term effects of COVID-19 on aggravating heart damage,
inflammation, and plaque activity have led to the hypothesis that
cholesterol metabolism may be involved and that medicines lowering all
of these unfavorable outcomes might be helpful tools for COVID-19
therapy. In this context, the pleiotropic benefits of statins
(beneficial effects beyond cholesterol-lowering) include
anti-inflammatory, immunomodulatory, and antithrombotic qualities, all
of which are observable before lipid-lowering is visible. (6)
Studies have shown that CRP levels are important inflammatory markers
which need to be studied in this disease. The findings might be
extremely useful in designing treatments for specific patients and
following up on them. (7)
Lymphocyte counts have been used for differential diagnosis in COVID-19
patients and are an important indicator. A recent meta-analysis shows
that those with lymphopenia have a 3-fold higher risk of developing
severe COVID-19. Lymphopenia is a prominent feature of COVID-19 and
lymphocyte counts may be a useful, easily available biomarker in
predicting the severity and clinical outcomes. (8)
Immunoglobulins IgM and IgG have an important role in confronting viral
diseases and are important markers for diagnosis Additionally, IgG,
IgM-specific antibodies targeting SARS-CoV-2 can also be found in the
majority of patients. Clarifying these immune-pathological variations
might indicate potential targets for immunotherapy and is important for
specialists in selecting the appropriate therapeutic care. (9)
However, despite numerous clinical studies and meta-analyses, any
reliable prognostic method that can predict patient progression to
severe disease based on cytokine levels at admission remains imprecise.
Studies have shown that higher inflammation and specific cytokine
profiles contribute to disease severity. Multivariate comparisons showed
that TNF-, IL-2, IL-6, IL-10, IL17, and CRP were statistically
different, while IFN and IL-4 were not. (10)
The COVID-19 pandemic’s global scope makes the need for a vaccine more
urgent than ever, in contrast to SARS and MERS, which often resolve on
their own after a local epidemic. Numerous diverse methods of vaccine
development have been adopted as a result of this pressing necessity.
First of all, because of their capacity to be generated using just
sequence information, novel vaccination platforms, such as nucleic acid
vaccines and viral vector vaccines, are quickly rising to the top of the
COVID-19 vaccine development field. (11) Mortality rates of COVID-19
have diminished in vaccinated individuals and societies with higher
vaccination rates have demonstrated lower mortality. Vaccination has
been shown in several studies to reduce morbidity and death. According
to an Italian study, the risk of SARS-CoV-2 infection, hospitalization,
and mortality gradually reduce after the initial two weeks. (12)
Although many clinical studies have been performed during the COVID-19
pandemic, however due to the continuing spread of the disease in many
countries and the diverse manifestations and mortality rates it is
necessary to elucidate the immune pathways involved for better diagnosis
and therapy and long term follow up.
In this work we studied the relationship between CRP and cholesterol
levels, lymphocyte counts and detection of IgM and IgG with IL6, IL10
and IL17 levels and compared them in vaccinated and unvaccinated healthy
and COVID-19+ patients in Iraq.