BackgroundQ fever is an endemic disease in different parts of Iran. This study aimed to investigate the prevalence of acute Q fever disease among at-risk individuals in northwestern Iran.MethodologyAn etiological study was carried out in 2013 in Tabriz County. A total of 116 individuals who were in contact with livestock and had a nonspecific febrile illness were enrolled in the study. IgG phase II antibodies against Coxiella burnetii were detected using ELISA.Principal findingsThe prevalence of acute Q fever was 13.8% (95% confidence interval [CI]: 8.0, 21.0%). Headache (87.5%) and fatigue and weakness (81.3%) were the dominant clinical characteristics among patients whit acute Q fever. Acute lower respiratory tract infection and chills were poorly associated with acute Q fever. Furthermore, 32% (95% CI: 24, 41%) of participants had a history of previous exposure to Q fever agent (past infection). Consumption of unpasteurized dairy products was a weak risk factor for previous exposure to C. burnetii.ConclusionThis study identified patients with acute Q fever in northwestern of Iran. The evidence from this study and previous studies conducted in different regions of Iran support this fact that Q fever is one of the important endemic zoonotic diseases in Iran and needs due attention by clinical physicians and health care system.

Coronavirus disease 2019 (COVID-19) is undoubtedly the most challenging pandemic in the current century with more than 253,381 deaths worldwide since its emergence in late 2019 (updated May 6th, 2020). COVID-19 is caused by a novel emerged coronavirus named as Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Today, the world needs crucially to develop a prophylactic vaccine scheme for such emerged and emerging infectious pathogens. In this study, we have targeted spike (S) glycoprotein, as an important surface antigen of SARS-CoV-2, to identify its immunodominant B- and T-cell epitopes. We have conducted a multi-method B-cell epitope (BCE) prediction approach using different predictor algorithms to discover most potential BCEs. Besides, we sought among a pool of MHC class I and II-associated peptide binders provided by the IEDB server through the strict cut-off values. To design a broad-coverage vaccine, we carried out a population coverage analysis for a set of candidate T-cell epitopes and based on the HLA allele frequency in the top most-affected countries by COVID-19 (update 02 April 2020). The final determined B- and T-cell epitopes were mapped on the S glycoprotein sequence, and three potential hub regions covering the largest number of overlapping epitopes were identified for the vaccine designing (I531–N711; T717–C877; and V883–E973). Here, we have designed two domain-based constructs to be produced and delivered through the recombinant protein- and gene-based approaches, including (i) an adjuvanted domain-based protein vaccine construct (DPVC), and (ii) a self-amplifying mRNA vaccine (SAMV) construct. The safety, stability, and immunogenicity of the DPVC were validated using the integrated sequential (i.e. allergenicity, autoimmunity, and physicochemical features) and structural (i.e. molecular docking between the vaccine and human Toll-like receptors (TLRs) 4 and 5) analysis. The stability of the docked complexes was evaluated using the molecular dynamics (MD) simulations. These rigorous in silico validations supported the potential of the DPVC and SAMV to promote both innate and specific immune responses in the animal studies.

Objectives: Brucellosis is a worldwide zoonotic disease with high morbidity in the absence of treatment. The early diagnosis of brucellosis is efficient to prevent chronic infections. The aim of this study is evaluation of nested PCR efficiency in comparison with conventional methods for diagnosis of human brucellosis. A total of 120 patients with brucellosis symptoms were included in this study. Serological and microbiological tests and nested PCR were used for detection of Brucella bacteria. Results: Based on serological tests, 60.83% (73/120) of individuals were positive for brucellosis which only 8.33% of cases were confirmed by blood culture. Among them, 55% of cases were positive in serum agglutination test (SAT≥1:160) and Coombs (C-SAT≥1:160) tests. Furthermore, 7 negative SAT cases were positive in C-SAT as evidence for chronic brucellosis. Also, 68.18% and 56.06% of SAT positive samples were positive in blood nested PCR and serum nested PCR respectively. The sensitivity of blood nested PCR was more than serum nested PCR, SAT≥1:160 and blood culture (P<0.001). The specificity of the blood and serum nested PCR was 100% compared with blood culture and SAT≥ 1:160. Our findings highlight high performance of nested PCR for diagnosis of both acute and chronic brucellosis.