Background: Streptococcus pneumoniae remains a major cause of invasive streptococcal diseases among all age groups, particularly infants and the elderly. Objectives: This study aimed to recognize and determine S. pneumoniae serotypes isolated from clinical specimens by multiplex polymerase chain reaction (PCR). Methods: A total of 105 pneumococcal strains were collected from nonvaccinated cases within the age range of 10 days to 92 years from five provinces of Iran within June 2017 to August 2019. The strains were cultured on blood agar. Biochemical analyses and molecular tests were performed for the primary identification of bacterial isolates. Capsular typing was carried out by multiplex PCR assay. Primers that target the capsular polysaccharide site were used in this study. Results: Out of 130 studied clinical specimens, 105 isolates of S. pneumoniae were detected and identified. The most frequently isolated capsular types were 6B, 14, 19A, and 1. Serotype distribution consisted of 83.5% of vaccine serotype and 16.5% of nonvaccine serotype. The serotype 6B was significantly more frequent (P < 0.05) among the invasive clinical isolates (75%) compared to that among their noninvasive counterparts (25%). The distribution of 13-valent pneumococcal conjugate vaccine (PCV-13) serotypes in invasive pneumococcal disease (IPD) and non-IPD revealed 83% and 84% of the isolated serotypes, respectively. Moreover, 83.5% of all the serotypes identified in the study were covered by PCV-13 serotypes. Conclusions: The common serotypes of invasive and noninvasive groups in Iran are covered by PCV-13.

Background: Evidence suggests that COVID-19 patients are subject to significant risks of thromboembolic complications. Objectives: We aimed to evaluate coagulation disorders in COVID-19 patients and determine their relationship with the disease outcome. Methods: This cross-sectional study was conducted on 106 COVID-19 patients hospitalized in Imam Khomeini Hospital, Ardabil, Iran. After the preliminary completion of the information forms, 3 cc of intravenous blood sample was taken from each patient to test for INR, PT, CBC, and D-dimer. Then, the patients were monitored, and clinical data were statistically analyzed using SPSS software, version 24. Results: Of 106 COVID-19 patients, 69 were discharged from the hospital, while 37 cases died. The mean age of the patients was 58.99 ± 15.94 years, and 56.6% were males. Significant differences were found between the surviving and deceased patients in D-dimer, LDH, PT, and INR levels (P < 0.05). Based on logistic regression analysis, only D-dimer was a significant predictor of mortality such that each unit increase in the D-dimer level increased the mortality risk by 0.99%. Conclusions: D-dimer has a higher sensitivity than other coagulation markers in terms of intensity. As bleeding is not as common as thrombotic events, anticoagulant therapy is recommended.

Background: The emerging problem of antibiotic resistance in Pseudomonas aeruginosa is a global health concern; hence, revealing innovative therapeutic approaches (such as designing an immunogenic vaccine candidate) is needed. There is no evidence of the availability of an effective vaccine that can combat the infection caused by this microorganism. Objectives: This research was conducted to develop a potential chimeric vaccine against P. aeruginosa using reverse vaccinology approaches. Methods: The present vaccine candidate comprised outer membrane protein F and I (OprF/OprI) and PopB with appropriate linkers. After applying meticulous immune-informatics investigation, the multi-epitope vaccine was created, including helper T lymphocyte (HTL), cytotoxic T lymphocyte (CTL), interferon gamma (IFN-γ), and interleukin 4 (IL-4) epitopes. Then, the physicochemical characteristics, allergenicity, toxicity, and antigenicity were analyzed. After investigating the secondary structure, the tertiary structure (3D) model was generated, refined, and validated via computational methods. Besides, the strong protein-ligand interaction and stability between the vaccine candidate and toll-like receptor 4 (TLR4) were determined via molecular docking and dynamics analyses. Moreover, in silico cloning accompanied by pET-22b (+) was used to achieve high translation efficiency. Results: Our results presumed that the chimeric-designed vaccine was thermostable and contained optimal physicochemical properties. This vaccine candidate was nontoxic and highly soluble and had stable protein and TLR4 interaction, adequately overexpressed in Escherichia coli. Overall, it could induce immune responses and repress this microorganism. Conclusions: Therefore, to inhibit Pseudomonas infections experimentally, the efficacy and safety of the vaccine design need to be validated.

Background: Strongyloides stercoralis is an intestinal nematode with worldwide distribution which is endemic in tropical and subtropical areas. It is unique in its ability to complete its entire life cycle and reinfect its human host via a phenomenon called autoinfection. The majority of infections are clinically asymptomatic or can manifest with gastrointestinal symptoms, such as heartburn, bloating, diarrhea, abdominal discomfort, gastroesophageal reflux disease (GERD), or symptoms related to the penetration of larvae through skin, including dermatitis and eosinophilia. Immunosuppressed patients, such as solid organ transplant patients with untreated strongyloidiasis are at great risk of hyperinfection, dissemination syndromes, and often fatal conditions associated with strongyloidiasis. Methods: In this retrospective single-center cross-sectional study, we evaluated 157 cases (131 heart, lung, and kidney transplant recipients and 26 kidney donors) in Tehran, Iran, from March 2020 to April 2021. Demographic information including age, gender, place of birth, place of residence, underlying disease, being the donor or recipient, history of previous transplant and type of transplant, travel history to endemic regions, and seropositivity for S. stercoralis were evaluated. Results: Among 157 cases with a mean age of 38.9 years, 40 (25.5%) cases tested positive for S. stercoralis antibodies. Out of 26 donors, eight cases were seropositive, and among 131 recipients, 32 cases were seropositive. There was no significant correlation between birth place and place of residence in endemic areas and seropositivity for S. stercoralis. None of the cases showed hypereosinophilia, hyperinfection, or disseminated syndrome. Also, we found no significant correlation between the type and time of transplant, history of previous transplants, and S. stercoralis infection. Conclusions: Universal screening for S. stercoralis latent infection is important in immunosuppressed patients, especially in solid organ transplants because of the high risk of hyperinfection and disseminated syndrome, which may culminate in death. Furthermore, screening for latent strongyloides infection in donors seems to be necessary because of the possibility of strongyloides infection being transmitted from donors to recipients.

Background: The COVID-19 pandemic has affected more than 180 countries and has killed more than half a million people up to now. Risk factors for death are not yet fully identified. Objectives: The present study aimed at comparing the clinical manifestations and risk factors for death between two groups of patients with COVID-19 aged under and above 50 in Qom Province, Iran. Methods: The current retrospective cohort study was conducted on 178 patients with COVID-19 in Qom Province. Patients were followed up until recovery or death. The source population was divided into four groups, of which 45 patients were randomly enrolled in the study. The first group included patients aged less than 50 discharged after recovery; the second group included patients less than 50 years who died from COVID-19; the third group consisted of patients above 50 discharged after recovery, and the fourth group included patients above 50 who died from COVID-19. The data, including COVID-19 clinical symptoms and presumptive risk factors for death, were collected and compared between groups. Results: The most common symptoms in hospitalized patients were shortness of breath (82.6%), cough (73.6%), and fever (71.9%), respectively. In the age group above 50, the prevalence of fever in the recovered subjects was higher than that of the ones who died from the disease (81.8% Vs. 53.3%). Headache and loss of senses of smell and taste were also more common in both age groups in the recovered subjects. In the age group under 50, subjects who died had higher BMI values, but in the age group above 50, subjects who died had lower BMIs. Conclusions: The results of the present study showed that obesity could be a risk factor for death in the age group under 50. The results also indicated that in both age groups, extrapulmonary symptoms were more common in recovered patients.

Background: Identification of the causes of gallstone would result in better planning for the prevention of this disease. One of the proposed risk factors for this problem is Helicobacter pylori (H. pylori) infection. Objectives: The purpose of this study was to determine the incidence rate of gallstone in patients with H. pylori gastritis. Methods: This was an observational study performed as a descriptive-comparative cross-sectional survey. We enrolled 169 consecutive patients with H. pylori gastritis admitted to Imam-Hossein Hospital, Tehran, Iran, in 2018, and gallstone frequency in them was determined and compared with other variables. Results: Overall, 14 (8.3%) patients had gallstone, and all the patients had H. pylori gastritis. There was no significant association between gallstone and H. pylori gastritis (P = 0.561). Conclusions: It may be concluded that gallstone frequency in patients with H. pylori gastritis is low, and there is no significant association between these two conditions.

: The most common viruses affecting immunocompromised hosts include cytomegalovirus, herpes simplex virus, varicella-zoster virus, influenza virus, measles virus, and adenovirus. Parainfluenza virus infection is common among human populations. It causes non-specific symptoms in immune-competent hosts; therefore, it may go undiagnosed. However, it is particularly dangerous for immunocompromised patients by presenting a high risk of morbidity and sometimes mortality among them. Patients who have bone marrow or solid organ transplantation need to follow an intense immunosuppressing routine, which leaves them extremely vulnerable to opportunistic agents such as parainfluenza viruses. Several factors determine the severity of parainfluenza virus infections, such as the type of the virus, the level of immunosuppression, and co-infection with other agents. Co-infection is especially important because it makes a correct differential diagnosis difficult. While almost all bodies of influenza infection information in immunocompromised patients are from studies of bone marrow transplant recipients, there are very limited data available on influenza infections in liver transplant patients. We present a liver transplant patient with severe parainfluenza pneumonia that was improved significantly with oral ribavirin and intravenous immunoglobulin. A 23-year-old female patient with a history of liver transplantation from 18 months ago presented with a one-week cough and tachypnea. Chest computed tomography demonstrated ground-glass opacities and diffuse infiltrates throughout both lungs. A multiplex polymerase chain reaction for the detection of respiratory viruses in the nasopharynx was positive for parainfluenza virus type 3 and she was successfully treated with oral ribavirin and intravenous immunoglobulin. Respiratory infection with the parainfluenza virus in immunocompromised adults, including transplant patients, is associated with significant morbidity and mortality, and early treatment with ribavirin and intravenous immunoglobulin may markedly improve their outcomes. To the best of our knowledge, this is the first case report of the successful treatment of parainfluenza infection with ribavirin and intravenous immunoglobulin in a patient with liver transplantation.

Background: Human parvovirus B19 is a single-stranded DNA and non-enveloped virus which belongs to the Parvoviridae family. The virus spreads through respiratory secretions and perinatal blood. B19 may cause serious complications in patients with cellular immunodeficiency that have no detectable antibodies to B19, such as aplastic crises in solid organs. Objectives: The present study aimed to investigate the prevalence of parvovirus B19 and to evaluate the presence of B19 DNA among blood donors in Golestan Province. Methods: Sera of 400 blood donors in Golestan Province who were negative for HIV, HbsAg, and HCV were tested for both IgG and IgM anti-B19 virus antibodies using the ELISA method, following which all sera were tested for the presence of B19 DNA by semi-nested PCR. Results: 242 (out of 400) subjects (60.5%; 95% CI) were positive for anti-B19 IgG, and 158 were negative for IgG antibody (39.5%; 95% CI). Moreover, all asymptomatic blood donors were negative for anti-B19 IgM. No viral genome was found in serum samples of donors. Conclusions: Since no viral genome was found in the donors' serum samples and the relatively high prevalence of anti HPV- B19 IgG in blood donors, it can be concluded that the possibility of B19 transmission through blood transfusion is low. However, special caution should be taken when transfusing blood to the high-risk groups such as pregnant women, immune-deficient patients, and those with hematological problems, particularly regarding IgG anti- HPV- B19 antibodies (HPV- B19-safe).

Context: Using smart mobile devices, called mobile health (mHealth), facilitates providing health services, speeds up the process, and reduces the costs and complications of direct services. Also, mHealth has many capabilities and applications in epidemic and pandemic outbreaks. This study aimed to identify mHealth applications in epidemic/pandemic outbreaks and provide some suggestions for tackling COVID-19. Methods: To find the relevant studies, searches were done in PubMed and Scopus by related keywords during 2014 - 2020 (March 10). After selecting the studies based on the inclusion and exclusion criteria, data were collected by a data-gathering form. Results: Of the 727 retrieved studies, 17 studies were included. All studies emphasized the positive effect of mHealth for use in epidemic/pandemic outbreaks. The main applications of mHealth for epidemic/pandemic outbreaks included public health aspects, data management, educational programs, diagnosis, and treatment. Conclusions: mHealth is an appropriate method for encountering epidemic/pandemic outbreaks due to its extensive applications. In the pandemic outbreak of COVID-19, mHealth is one of the best choices to use in the patient-physician relationship as tele-visits, using in fever coach, providing real-time information for healthcare providers, population monitoring, and detecting the disease based on obtained data from different locations.