Angiotensin-Converting Enzyme-2 (ACE-2) with Interferon-Induced Transmembrane Protein-3 (IFITM-3) Genetic Variants and Interleukin-6 as Severity and Risk Predictors among COVID-19 Egyptian Population

Introduction The host genetic background is a crucial factor that underlies the interindividual variability of COVID-19 fatality and outcomes. Angiotensin-converting enzyme-2 (ACE-2) and interferon-induced transmembrane protein-3 (IFITM-3) have a key role in viral cell entrance and priming. The evoked immune response will also provide a predictive prognosis for COVID-19 infection. This study aimed to explore the association between ACE-2 and IFITM-3 genotypes and their corresponding allele frequencies with disease severity indices in the Egyptian COVID-19 population. The serum level of interleukin-6, as a biomarker of hyperinflammatory response, and cytokine storm, was correlated with disease progression, single nucleotide polymorphisms (SNPs) of the selected receptors, and treatment response. Methodology. We enrolled 900 COVID-19-confirmed cases and 100 healthy controls. Genomic DNA was extracted from 200 subjects (160 patients selected based on clinical and laboratory data and 40 healthy controls). The ACE-2 rs2285666 and IFITM-3 rs12252 SNPs were genotyped using the TaqMan probe allelic discrimination assay, and the serum IL-6 level was determined by ELISA. Logistic regression analysis was applied to analyze the association between ACE-2 and IFITM-3 genetic variants, IL-6 profile, and COVID-19 severity. Results The identified genotypes and their alleles were significantly correlated with COVID-19 clinical deterioration as follows: ACE2 rs2285666 CT + TT, odds ratio (95% confidence interval): 12.136 (2.784–52.896) and IFITM-3 rs12252 AG + GG: 17.276 (3.673–81.249), both p < 0.001. Compared to the controls, the heterozygous and mutant genotypes for both SNPs were considerable risk factors for increased susceptibility to COVID-19. IL-6 levels were significantly correlated with disease progression (p < 0.001). Conclusion ACE-2 and IFITM-3 genetic variants are potential predictors of COVID-19 severity, critical outcomes, and post-COVID-19 complications. Together, these SNPs and serum IL-6 levels explain a large proportion of the variability in the severity of COVID-19 infection and its consequences among Egyptian subjects.

Introduction.Te host genetic background is a crucial factor that underlies the interindividual variability of COVID-19 fatality and outcomes.Angiotensin-converting enzyme-2 (ACE-2) and interferon-induced transmembrane protein-3 (IFITM-3) have a key role in viral cell entrance and priming.Te evoked immune response will also provide a predictive prognosis for COVID-19 infection.Tis study aimed to explore the association between ACE-2 and IFITM-3 genotypes and their corresponding allele frequencies with disease severity indices in the Egyptian COVID-19 population.Te serum level of interleukin-6, as a biomarker of hyperinfammatory response, and cytokine storm, was correlated with disease progression, single nucleotide polymorphisms (SNPs) of the selected receptors, and treatment response.Methodology.We enrolled 900 COVID-19-confrmed cases and 100 healthy controls.Genomic DNA was extracted from 200 subjects (160 patients selected based on clinical and laboratory data and 40 healthy controls).Te ACE-2 rs2285666 and IFITM-3 rs12252 SNPs were genotyped using the TaqMan probe allelic discrimination assay, and the serum IL-6 level was determined by ELISA.Logistic regression analysis was applied to analyze the association between ACE-2 and IFITM-3 genetic variants, IL-6 profle, and COVID-19 severity.Results.Te identifed genotypes and their alleles were signifcantly correlated with COVID-19 clinical deterioration as follows: ACE2 rs2285666 CT + TT, odds ratio (95% confdence interval): 12.136 (2.784-52.896)and IFITM-3 rs12252 AG + GG: 17.276 (3.673-81.249),both p < 0.001.Compared to the controls, the heterozygous and mutant genotypes for both SNPs were considerable risk factors for increased susceptibility to COVID-19.IL-6 levels were signifcantly correlated with disease progression (p < 0.001).Conclusion.ACE-2 and IFITM-3 genetic variants are potential predictors of COVID-19 severity, critical outcomes, and post-COVID-19 complications.Together, these SNPs and serum IL-6 levels explain a large proportion of the variability in the severity of COVID-19 infection and its consequences among Egyptian subjects.

Introduction
A novel pathogen called SARS-CoV-2 caused a viral respiratory infection known as the 2019 coronavirus disease (COVID-19) that spread across the globe.Approximately, 20% of the COVID-19 patients experience either severe pneumonia or a critical illness that results in death although the majority of the patients are asymptomatic or show mild sickness [1].
Host characteristics such as sex, concomitant comorbidities, ethnicity, and age group are ultimately related to the observed variation in clinical presentation and consequences of SARS-CoV-2 infection [2].Recent research suggests that the genetic makeup of the host may also be a factor in the disparity between COVID-19 progression and case fatality rates [3].
Te primary host cell receptor for the SARS-CoV-2 viral spike glycoprotein is ACE-2 [5].It enhances the entry of the virus into the cell, causing the fnal infection [6,7], and alters host susceptibility to SARS-CoV-2, refecting ACE-2 spike glycoprotein interaction [8].Genetic polymorphisms that control ACE-2 expression have the potential to signifcantly alter COVID-19 severity and host cell response [9,10].Several SNPs were investigated in this context, including rs182366225, rs2097723, rs1027571965, and rs2285666.Te majority of variations have been shown to be linked to ACE-2 overexpression [11].
Te IFITM family plays a pivotal role in the pathogenesis of many viral diseases.Te IFITM-3 gene encodes an interferon-induced membrane protein with broad antiviral activity against infuenza A, H1N1 virus, and SARS-CoV-2.Tey mediate an innate immune response by regulating the fusion of the invading virus and endocytic vesicles directing it to lysosomes.IFITM-3 can further alter membrane rigidity and curvature to prevent virus membrane fusion.Such action is required to inhibit the release of viral particles into the cytoplasm, thus controlling viral propagation [12].Variants in the IFITM-3 gene have been consistently associated with changes in expression and the risk of severe COVID-19 disease including rs6598045 [13], rs34481144 [14], and rs12252 [1].
Te immunopathogenesis of COVID-19 is mostly infuenced by the host infammatory response and secreted cytokines, in addition to genetic diferences.Despite varying degrees of evidence, the development of a cytokine storm led to the clinical form of COVID-19 infection deteriorating from mild to severe.Such a phenomenon has raised the question of whether exaggerated immunological sequelae can determine the severity of symptoms and contribute to a poorer outcome among COVID-19 patients [15].
Cytokine storm is an interesting point in SARS-CoV-2 infection.COVID-19 patients have elevated levels of infammatory cytokines, particularly IL-6 [16,17].Furthermore, the potential predictive signifcance of IL-6 in terms of the need for mechanical ventilation or death has been confrmed [18].Various existing medications can block the IL-6 pathway; however, only tocilizumab (an IL-6 receptor antagonist) has had a reasonable efect in COVID-19 [19].
Likewise, this study was conducted to increase the understanding of how the genetic background infuences the severity of SARS-CoV-2 infection.We investigated the relationship between COVID-19 progression and genetic variants in both ACE-2 and IFITM-3.We perhaps ofer a strategy for identifying potential SNPs as prognostic markers with a particular attention to concurrent pandemic waves, serum IL-6 levels, clinical criteria, laboratory investigations, and treatment response among COVID-19 Egyptian population.S1 and S2).

Subjects and Methods
Senior radiologists at MUHs used the Reporting and Data System (CO-RADS), a categorical assessment scheme for lung involvement in COVID-19, to undertake radiologic examination to estimate the severity of COVID-19.It involves a chest high-resolution CT, which on a scale from 1 (extremely low) to 6 (very high) predicts COVID-19 in patients with moderate to severe symptoms quite well [21].

Patients' Data Collection.
Senior clinicians reviewed the medical records of the enrolled patients to gather information on their demographics, preexisting comorbidities, presenting symptoms, laboratory results (Hb, white blood cells (WBCs) count, platelets count, lymphocytes, CRP, D dimer, ferritin, LDH, AST, ALT, BUN, and creatinine serum levels), treatment regimens and response, complications, and expected outcomes.Daily data on the disease stage, the presence of fever, SpO 2 , partial pressure of oxygen in arterial blood (PaO 2 ), and the necessity for invasive or noninvasive ventilator assistance were checked at the baseline and during hospitalization.

2.4.
Patients' Follow-Up.Te term "post-COVID-19 syndrome" describes symptoms that may be brought on by ongoing infammation, organ damage, general hospital side efects, protracted ventilator support (postintensive care syndrome), or the impacts of underlying medical disorders [22].After discharge, convalescent COVID-19 patients were assessed and monitored for up to 2 months for the occurrence of post-COVID-19 syndrome and the most prominent manifestations.

Cases Selection.
Because of limited fnancial support, two hundred subjects, i.e., 160 cases (40 mild/moderate, 60 severe, and 60 critical) and 40 healthy controls were selected based on clinical, laboratory, and radiological fndings and subjected to genotypic analysis of both ACE-2 (rs2285666) and IFITM-3 (rs12252) SNP variants as well as serum IL-6 profling as follows.

Blood Sample Collection and Preparation.
A septic venipuncture was used to obtain 5 ml of venous blood and was processed as follows: (i) 3 ml of blood were placed into the EDTA-containing tube for DNA extraction and genotyping of ACE-2 (rs2285666) and IFITM-3 (rs12252) SNPs by using the TaqMan allelic discrimination assay technique.(ii) Te remaining 2 ml of blood was transferred into the plain tube, left to clot for 15 min, and centrifuged for 10 min at 4000 r.p.m.Te serum obtained was stored at −80 °C until analysis of serum IL-6 by ELISA.

Interleukin-6 Serum Levels.
Before undergoing anti-IL-6 therapy, the 1st reading of serum IL-6 levels was determined using an enzyme-linked immunosorbent assay with a human IL-6 ELISA kit (Chemux Bio Science, Inc., USA) in accordance with the manufacturer's instructions.Kinetic measurements of serum IL-6 (follow-up reading) were recorded for forty-six patients who received cilizumab (Actemra 20 mg/ml, Roche) as anti-IL-6 therapy 72 hours after treatment initiation at a dose of 4-8 mg/kg/d I.V. for 2 doses 12-24 h apart.

Statistical Analysis.
Te distribution of the variables' variance was assessed for normality.Nonparametric continuous variables were compared using the Kruskal-Wallis test between the groups that were examined, and the results were summarized using means, medians, and interquartile ranges (IQRs).Te Chi squared test was used for categorical variables.A value of p < 0.05 was regarded as statistically signifcant for all the tests.Te association among genetic International Journal of Microbiology variations, IL-6, and other various parameters with COVID-19 susceptibility and outcomes was examined using a logistic regression approach.By analyzing genotype distribution using the Kruskal-Wallis test and stratifying by disease outcome, it was possible to determine the relationship between SNPs and clinical characteristics.STATA v.13 statistical software tools (StataCorp, TX, USA) were used to carry out the analysis.2).

Te Relation between COVID-19 Severity and Patients'
Outcomes.ICU admission was more frequently recorded among patients in the third pandemic wave than among those in the fourth one (73.7% vs. 47.3%).In addition, the death rate was higher among patients in the third wave than among those in the fourth wave (55.3% vs. 44.2%),while recovery and post-COVID-19 sequelae were signifcantly more common during the fourth wave (52.1% vs. 34.2%and 34.2% vs. 24.7%,respectively), as shown in Table 3.

Genotypes and Allelic Distribution of Both ACE-2 (rs2285666) and IFITM-3 (rs12252) Polymorphisms.
Importantly, we observed that both heterozygous CT and mutant TT genotypes of rs2285666 were more prevalent among severe (26.7% and 53.3%, respectively) and critical (33.3% and 53.3%, respectively) cases compared to either mild/moderate cases (15% and 10%, respectively) or the control group (20% and 5%, respectively), with a signifcant diference (p 1 < 0.001, p 2 <0.001, and p 0 < 0.001).In addition, the T allele displayed a pattern of 70%, 66.7%, and 17.5% for critical, severe, and mild/moderate cases, respectively.Te mutant genotype GG for rs12252 of IFITM-3 was predominant among severe (60.0%) and critical (41.7%) cases compared to both mild/moderate cases and controls (5% for each).A parallel distribution was also detected for the G allele, with higher percentages among severe (70.0%) and critical cases (61.7%).On the other hand, no statistically signifcant diference was noticed between the mild/moderate and control groups regarding genotypes and allelic frequencies of both SNPs (p > 0.05), as shown in Table 4. Te dominant, recessive, codominant, and overdominant models for genotype combinations for both SNPs are shown in Tables S8 and S9.International Journal of Microbiology manifestations (Table S6).Similarly, the heterozygous AG and mutant GG variants of rs12252 were correlated with poorer consequences among the studied cases as well.

Relationship between ACE-2 (rs2285666) and IFITM-3 (rs12252) Genotypes and Clinical
Dyspnea and ARDS were common among patients with AG and GG variants compared to the reference AA genotype (60.9% and 74.6% vs. 41.2% for dyspnea and 47.8% and   S7.   7 and 8.

Discussion
Accompanying the spread of COVID-19 disease all over the world, recognizing factors connected to the susceptibility and outcome of the disease is at the top of medical and pharmacological concerns [23].Tis work was performed to identify possible COVID-19 prognostic markers with special concern for ACE-2 and IFITM-3 genetic variations and IL-6 level assays.COVID-19 susceptibility and severity among studied cases were linked to age and associated comorbidities.Nikkhoo et al. documented the same fnding [24,25].
Te diseased patients' outcome in our study showed a signifcant decline in clinical and laboratory conditions in the third pandemic wave compared to the fourth one, especially for ICU hospitalization and death records.Such observations were also reported in Iran by Amin et al. on COVID-19 consecutive waves with increased severity and mortality during the early three waves compared to followers [26].
Laboratory data from our patients and fndings from further research revealed that patients with severe and critical illness had considerably higher levels of CRP, Ddimer, and serum ferritin compared to mild/moderate cases (Tables S1 and S2) [27,28].In addition, Gómez-Haranz et al.
reported signifcant correlations between case severity and diferent laboratory markers, including CRP, D-dimer, and ferritin levels [29].Fever, coughing, and dyspnea were mostly the prominent presentations in patients during the third pandemic wave.Tese observations were supported by other studies [30][31][32].
COVID-19-infected patients can develop variable illnesses with unexpected consequences.Although many disease predictors have been reported, much research is still needed.Infection rates and outcomes could be dependent on the host's genetic background, especially those afecting the virus-cell interaction [27].Te main fnding in this study was the higher prevalence of hetero and mutant genotypes of ACE-2 rs2285666 among severe (CT 26.7% and TT 53.3%) and critical (CT 33.3% and TT 53.3%) cases than that of controls (CT 15.0% and TT 10%).Tese genotypes were risk factors for COVID-19 severity and enhanced susceptibility according to logistic regression analysis (Tables 7).Likewise, the T allele displayed the same pattern, with 66.7% and 70% predominance among severe and critical cases, respectively.Tese data were similar to recent data reported by Abdel Sattar et al. in Egypt, who found that the genotypes CT and TT and the T allele were high predictors of severe illness [28].In contrast, Sidhawani et al. in Pakistan found that the TT genotype of rs2285666 was protective, while the CC genotype raised the likelihood of COVID-19 disease [27].Çelik et al. did not fnd any link between the rs2285666 polymorphism and disease severity [33].
Te ACE-2 rs2285666 variant is located in the third intron of the gene; thus, the expression of the gene is afected by an alternative splicing mechanism [34].According to Asselta et al., the change from C to T strengthened the splicing site by 9.2%, leading to enhanced production of the ACE-2 protein [35].In addition, Gemmati and Tisato declared the ACE-2 gene as a "frst genetic gateway" involved in COVID-19 infection and severity [36].
A study by Martinez Gómez et al. showed that when the T allele of rs2285666 was present, the risk for developing severe and critical consequences in COVID-19 was increased, especially in men.Te authors also declared a link between the TT genotype of rs2285666 and an increased likelihood of more serious sequelae with SARS-CoV-2 infection [37].Furthermore, Benetti et al. showed that ACE-2 genetic variations afect protein function and may result in difering susceptibility and progression of COVID-19 infection [38].Srivastava et al. stated that genetic diferences in ACE-2 afect susceptibility to COVID-19, and carriers of the T allele had a decreased infection rate in Indian populations [39].However, it is crucial to note that several variables contribute to SARS-CoV-2 infection, and ACE-2 may not be the sole gene involved.Ethnic differences in populations as well as variations in gene expression could be responsible for these discrepancies [37].
Endogenous expression of IFITM-3 was shown to be necessary for the replication of numerous coronaviruses as previously mentioned by Xie and colleagues and Wang and colleagues [40,41].Te altered expression of IFITM-3 changes the cellular expression and localization of ACE-2 with subsequent opposing or enhancing unclear impacts on virus entry [42].According to their reports, IFITM-3 International Journal of Microbiology rs12252 AG and GG polymorphic variants were predominant in severe and critical groups, which could be explained by enhanced ACE-2 binding availability.Tese data coincided with our fndings, where ACE-2 (CT + TT) and IFITM-3 (AG + GG) SNP associations were the best indicators of illness severity by logistic regression analysis (Table 6).Our study was in line with that by Zhang et al., where the rising frequency of genotype GG for rs12252 was reported among severe cases.A meta-analytic study involving more than four studies from England, Italy, and Spain showed a signifcant association of the IFITM-3 rs12252/ACE-2 rs2285666 polymorphism with COVID-19 susceptibility [43].However, neither rs2285666 nor rs12252 were shown to be substantially related to illness severity [23].
Te mechanisms by which IFITM-3 rs12252 with the G allele is associated with COVID-19 deterioration are not completely understood.Te variation is thought to mediate lowered IFITM-3 protein expression and, as a result, weakened the antiviral activity due to truncation of the encoded 21-amino acid or alteration of the protein's cellular localization between the membrane of the cell and endosomal vesicles [44][45][46].
Te current study explored IL-6 as a disease progression marker owing to its characteristic role in the COVID-19associated cytokine storm, refecting its importance as a pharmacological target.Our statistics demonstrated that elevated serum IL-6 levels were signifcantly correlated with severe and critical illness (p < 0.001).Many studies have been conducted to examine the predictive usefulness of IL-6 on various clinical features of COVID-19 infection with high specifcity [19,47].Furthermore, IL-6 levels were found to be substantially related to various clinical and laboratory indicators predicting a systemic infammatory response, such as CRP, ferritin, D-dimer, and LDH (Table S3).Te same correlation was reported by other studies; however, IL-6 seemed to be the major prognostic efector [24,47].
IL-6 levels together with ACE-2 rs2285666 and IFITM-3 rs12252 genetic variants were suggested here as signifcant predictors for COVID-19 fatality.Interestingly, we observed higher serum IL-6 levels among patients harbouring the CT variant compared to the wild CC type of rs2285666, as provided in the supplementary fles (Table S4).However, Beyranvand et al. did not fnd any correlation between IL-6 levels and SNP polymorphisms of the two target receptors [48,49].
IL-6 inhibitors are strongly recommended by the WHO and National Institute for Health and Care Excellence (NICE) in COVID-19 patients either prescribed alone or with corticosteroids [50].Te studies implemented by Sciascia et al. [51,52] demonstrated an obvious improvement among most patients who received tocilizumab (TCZ), as proven in our results, particularly for mild/moderate cases (Table 5).In addition, Salvati et al. declared that the administration of TCZ increased the likelihood of survival among moderate cases [53].Similar to our results, Hermine et al. documented that in critically ill adult patients with COVID-19 pneumonia, anti-IL-6 receptor therapy did not improve early survival in the absence of mechanical respiration [54].Perhaps, the cytokine storm and shooting of the IL-6 levels occurring in both severe and critical cases hindered the efect of TCZ.Contrary to our results, Shankar-Hari and colleagues demonstrated a clinical beneft (84.9%) with the use of TCZ in COVID-19 patients requiring organ support with hypoxemia and/or systemic infammation [55].
Te majority of people who have COVID-19 recover completely; however, approximately 10-20% develops a variety of mid-and long-term sequelae after recovering from their original sickness [56].According to our results, patients in diferent severity groups experienced post-COVID-19 symptoms in variable proportions.Carvalho-Schneider et al. [57,58] documented the occurrence of dyspnea and fatigue in 30% and 40% of COVID-19 patients, International Journal of Microbiology respectively, during their follow-up study, which partially matches our results showing dyspnea and fatigue being persistent in 30% and 20%, and 40% and 30% of patients within the third and fourth waves, respectively (Table S5).
Approximately, 80% of the noncritical patients with COVID-19 recovered completely, and death was recorded only among the critical cases [59].Tese fndings were in line with our results.In a study conducted by Abdelhafz et al., the prevalence of post-COVID-19 symptoms was 87.63% and fatigue was the most frequent symptom (60.86%) [60].

Conclusion
Both ACE-2 and IFITM-3 SNPs were amongst the highest determinants of COVID-19 severity, together with IL-6, CRP, D-dimer, ferritin, preexisting comorbidities, and age.IL-6 is a prognostic and therapeutic target for COVID-19 patients.Both SNPs and serum IL-6 levels could explain a large proportion of variability in the susceptibility and severity of COVID-19 infection and outcome among Egyptian subjects.

Study Limitation.
We missed recording some early signs and symptoms of admitted patients due to difcult communications with the patients, particularly those admitted immediately with severe and critical forms of the disease and thus relied solely on their recorded data.
Tere was difculty in performing genotyping and interleukin-6 ELISA level analysis for more than two hundred participants due to fnancial issue.

4
2.1.Study Eligibility and Design.Tis case-control study was carried out at the Medical Microbiology and Immunology Department in collaboration with the Chest Department and Central Laboratory of the Faculty of Medicine, Menoufa University Hospitals (MUHs).
Meanwhile, the diference was highly signifcant for age distribution (p < 0.001).Smoking and the majority of underlying comorbidities were found to signifcantly difer across the groups under study (p < 0.001), as shown in Table1.Fever, Data, Associated Comorbidities, and Clinical Presentation of the Studied Subjects.Male predominance was noticed among both studied groups, but the diference was not statistically signifcant.
Data in the Studied Patients.

Table 1 :
Comparison between the studied populations regarding sociodemographic data and associated comorbidities.

Table 2 :
Comparison between the studied populations regarding clinical presentation and complications.
*p: p value for comparing between the two studied groups.* Statistically signifcant at p ≤ 0.05.ARDS: acute respiratory distress syndrome and AKI: acute kidney injury.

Table 3 :
Relation between COVID-19 severity and patients' outcomes among the studied cases of wave 3 and 4. , p 2 < 0.001 * , p 3 < 0.001 * , p 4 � 0.002 * p 0 : p value for the Chi square test for comparing between mild/moderate and severe and critical in both groups.Sig.bet.grps: p value for comparing between group I and group II regarding diferent outcomes parameters (total) as follows: p 1 : p value for comparing between group I and group II regarding total recovery.p 2 : p value for comparing between group I and group II regarding total ICU admission.p 3 : p value for comparing between group I and group II regarding total death.p 4 : p value for comparing between group I and group II regarding total post-COVID-19 syndrome.

Table 4 :
Genotypes and allelic frequencies of ACE-2 (rs2285666) and IFITM-3 (rs12252) among the studied cases regarding COVID-19 severity., A\A: wild genotype.A\G, C\T: hetero genotype.G\G, T\T: mutant genotype.MC: Monte Carlo.χ 2 : Chi square test.p0: p value for the Chi square test for comparing between control and each other groups.p 1 : p value for the Chi square test for comparing between mild/moderate and severe.p 2 : p value for the Chi square test for comparing between mild/moderate and critical.p3: p value for the Chi square test for comparing between severe and critical.�200)from Both Pandemic Waves.As shown in Table5, the serum IL-6 profle denoted higher levels along with increasing disease severity and clinical deterioration, with a highly signifcant diference among the studied cases (p < 0.001).

Table 5 :
Comparison between IL-6 serum 1 st reading among the selected participants (n � 200) of both pandemic waves., p 2 < 0.001 * , p 3 � 0.009 * IQR: interquartile range SD: standard deviation.p: p value for comparing between the four studied groups.p 0 : p value for comparing between control and each other groups.p 1 : p value for comparing between mild/moderate and severe.p 2 : p value for comparing between mild/moderate and critical.p 3 : p value for comparing between severe and critical.

Table 6 :
Comparison between IL-6 levels before and after receiving anti-IL-6 treatment regarding group severity (n � 46).
*SD: standard deviation.p: p value for relation between 1 st reading and follow-up reading.* Statistically signifcant at p ≤ 0.05.
: odds ratio.CI: confdence interval.LL: lower limit.UL: upper limit.#All variables with p < 0.05 were included in the multivariate analysis.* Statistically signifcant at p ≤ 0.05. OR
OR: odds ratio.CI: confdence interval.LL: lower limit.UL: upper limit.#All variables with p < 0.05 were included in the multivariate analysis.*Statistically signifcant at p ≤ 0.05.International Journal of Microbiology