Designing Pathway-Controlled Multicomponent Ultrashort Peptide Hydrogels with Diverse Functionalities at the Nanoscale for Directing Cellular Behavior.

Tuning self-assembling pathways by implementing different external stimuli has been extensively studied, owing to their effective control over structural and mechanical properties. Consequently, multicomponent peptide hydrogels with high structural tunability and stimuli responsiveness are crucial in dictating cellular behavior. Herein, we have implemented both coassembly approach and pathway-dependent self-assembly to design nonequilibrium nanostructures to understand the thermodynamic and kinetic aspects of peptide self-assembly toward controlling cellular response. Our system involved an ultrashort peptide gelator and a hydrophilic surfactant which coassembled through different pathways, i.e., heat-cool and sonication methods with variable energy input. Interestingly, it was possible to access diverse structural and mechanical properties at the nanoscale in a single coassembled system. Further, the hydrophilic surfactant provided additional surface functionalities, thus creating an efficient hydrophilic matrix for cellular interaction. Such diverse functionalities in a single coassembled system could lead to the development of advanced scaffolds, with applications in various biomedical fields.

Conformation Controlled Hydrogelation of Minimalistic α, γ Hybrid Peptide.

A majority of short peptide (≤7 amino acids) hydrogels are primarily assembled via cross ß-structure formation. In contrast to the natural trend, herein, we report the formation of supramolecular hydrogel from the ultrashort hybrid folded peptide composed of canonical α-amino acid and noncanonical γ-amino acid, Fmoc-γPhe-Phe-OH. The designed hybrid peptide hydrogel is composed of entangled fibers, has viscoelastic properties, exhibits proteolytic stability, and exhibits cytocompatibility with L929 fibroblast cells. Mutating the peptide sequence by altering the position of γPhe from the N-termini to C-termini transforms the self-assembly into crystalline aggregates. Combining FTIR, 2D NMR, and DFT calculations revealed that the hydrogel-forming peptide adopts a C9 H-bonded conformation, resembling the well-known γ-turn. However, the isomeric hybrid peptide adopts an extended structure. The present study highlights the importance of secondary structure in the higher order assembly of minimalist hybrid peptides and broadens the range of secondary structures to design short peptide-based hydrogels.

Designing Cardin-Motif Peptide and Heparin-Based Multicomponent Advanced Bioactive Hydrogel Scaffolds to Control Cellular Behavior.

Recently, peptide and sugar-based multicomponent systems have gained much interest in attaining the sophisticated structure and biofunctional complexity of the extracellular matrix (ECM). To this direction, we have designed for the first time a biologically relevant minimalist Cardin-motif peptide capable of binding ECM-derived glycosaminoglycans. Herein, we explored Cardin-motif peptide and heparin-based biomolecular matrix by employing simple noncovalent interactions at the molecular level. Interestingly, this peptide was inadequate to induce hydrogelation at ambient pH due to the presence of basic amino acids. However, addition of heparin successfully triggered its gelation at physiological pH following favorable electrostatic interactions with heparin. Importantly, the newly developed scaffolds displayed tunable nanofibrous morphology and superior mechanical properties as controlled simply by the differential mixing ratio of both biomolecular entities. Additionally, these composite scaffolds could closely mimic the complexity of ECM as they demonstrated superior biocompatibility and enhanced growth and proliferation of neural cells as compared to the peptide scaffold.

COVID-19 Pandemic in Malegaon: SUTRA over the Three Waves.

Over the past two years, the COVID-19 pandemic has seen multiple waves with high morbidity and mortality. Lockdowns and other prompt responses helped India's situation become less severe. Although Malegaon in the Indian state of Maharashtra has a high population density, poor hygienic standards, and oppositional local community views toward national pandemic addressing measures, it is nevertheless reasonably safe. To understand the possible reasons serosurvey was conducted to estimate the anti-SARS-CoV-2 neutralizing antibody levels in the Malegaon population. Also, we did SUTRA mathematical modeling to the Malegaon daily data on COVID-19 attributable events and compared it with the National and state level. The case fatality rate (CFR) in Malegaon city for the first, second, and third waves was 3.25%, 2.25%, and 0.39%, respectively. The crude death rate (CDR) for Maharashtra ranked first for the initial two waves and India for the third wave. Malegaon, meanwhile, finished second in the first two waves but fared best in the third. The Vaccination coverage for the first dose before the second wave was only 0.34% but had risen to 64.46% by 12 Oct 2022. By then, the second and booster dose coverage was 27.55% and 2.38%, respectively. Serosurvey did between 12 and 18 Jan 2022 showed a 93.93% anti-SARS-CoV-2 neutralizing antibody presence. SUTRA modeling elucidated the high levels of antibodies due to the pandemic-reach over 102% by the third wave. The serosurvey and the model explain why the pandemic severity in terms of duration and CFR during the subsequent waves, especially third wave, was milder compared to the first wave in spite of low vaccination rates. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-023-01096-3.

Post vaccination antibody titres of hepatitis B surface antigen (anti-HBs) in a mixed cohort of health care workers.

Background: Hepatitis B (HepB) is an important vaccine preventable infection among healthcare workers (HCWs). Vaccination against Hep B virus, remains the foremost preventive approach. This study aims to measure the antibody titres to Hep B surface antigen (anti-HBs) in a mixed cohort of HCWs. It also aims to study the association between time since vaccination and the anti-HBs titres thus evaluating the duration of seroprotection. Methods: A total of 200 HCWs, including nursing students (n = 112), nursing staff (n = 49), laboratory technicians (n = 30) and doctors (n = 9) who had received all three doses of the Hep B vaccine and met the inclusion criteria of having taken all three doses of vaccine were included in this study. Anti-HBs titres were estimated by bioMérieux mini VIDAS® automated immunoassay based on the principle of enzyme-linked fluorescence assay. Results: Two hundred subjects aged 19 to 52 years were included in the study; mean age was 27.29 ± 0.568 years. Duration since vaccination in the study cohort was ≤ 5 years in 149 (74.5.0%), 6-10 years in 20 (10.0%) and >10 years in 31 (15.5%) subjects. Postvaccination antibody titres were > 100 mIU/ml in 85.0%, 10-100 mIU/ml in 11.0% and ≤ 10 mIU/ml in 3.5%. There was a decline noted in antibody titres as duration after vaccination increased. Increasing age was associated with falling protective titres. Conclusion: The study revealed that majority of the HCWs had adequate anti-HBs titres and were protected after vaccination.

Evaluation of a novel sputum processing ReaSLR methodology for improving sensitivity of smear microscopy in clinical samples.

Background: Early case detection is a crucial step in the control of tuberculosis (TB). Sputum smear microscopy is the primary method of TB diagnosis in developing countries. The modified Petroff's method using sodium hydroxide at concentrations ranging between 2% and 4% to digest the specimen is widely used in developing countries. A novel ReaSLR (ReaMetrix's Sputum Liquefying Reagent) methodology has been proposed as a simple, easy, low-cost, and better alternative to conventional methods for sputum processing. This study was undertaken to evaluate the performance of the ReaSLR method of sputum processing in comparison with that of the modified Petroff's method. Methods: Early-morning sputum samples were collected. After preparing a direct smear, each sample was divided into two equal halves and processed by both the methods, i.e., modified Petroff's method and ReaSLR method. Direct smears were graded according to Revised National Tuberculosis Control Program grading, and smears prepared after processing by the two different methods were graded according to Center for Disease Control and Prevention grading. Smear microscopy results were compared taking culture results of samples processed by the modified Petroff's method as the gold standard. Results: The rate of smear positivity with the modified Petroff's method (22.22%) was found to be higher than that with direct smear microscopy (13.56%; p = 0.0002) and the ReaSLR method (17.32%; p = 0.04). The modified Petroff's method was found to be 26.76% more sensitive than direct microscopy and 15.59% more sensitive than the ReaSLR method. Conclusion: The ReaSLR method was not superior to the modified Petroff's method for smear microscopy. Although this method was more sensitive than the direct method in smear microscopy, the modified Petroff's method performed much better than the ReaSLR method.

Probable vertical transmission of severe acute respiratory syndrome coronavirus 2 infection from mother to neonate.

The pandemic spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has affected 188 countries and territories. Altered physiological status during pregnancy makes a mother vulnerable to severe SARS-CoV-2 infection. The virus may be transmitted from mother to baby during antenatal period or postnatal period. Although the primary mode of transmission of the virus is by respiratory droplets, there is emerging evidence of in utero transmission from mother to foetus. In this rare case report, we describe one such episode of probable vertical transmission. To the best of our knowledge, this is the second systematically investigated Indian case, indicating in utero transmission of SARS-CoV-2 from mother to foetus.

Whole genome sequence of colistin-resistant Escherichia coli from western India.

BACKGROUND: With virtually dried out new antibiotic discovery pipeline, emergence and spread of antimicrobial resistance is a cause for global concern. Colistin, a cyclic polypeptide antibiotic, often regarded as last resort for multi drug resistance gram-negative bacteria, is also rendered ineffective by horizontal transfer of resistance genes. Surveillance of colistin resistance in GNB is essential to ascertain molecular epidemiology. METHODS: Whole genome sequencing (WGS) of an unusual colistin resistant urinary isolate of Escherichia coli was performed using Illumina MiSeq platform using 2x250bp V2 chemistry by following the manufactures protocol (Illumina Inc. USA). Multiple web-based bio-informatic tools were utilized to ascertain antibiotic resistant genes. RESULTS: An approximate 5.4 Mb of genome of the urinary isolate AFMC_UC19 was sequenced successfully. Mobile colistin resistance gene (mcr) on the plasmid responsible for horizontal spread was absent in the isolate. CONCLUSION: Colistin resistance has been reported previously in Klebsiella pneumoniae and it is a rare occurrence in Escherichia coli in Indian setting. Although the isolate lack mcr mediated colistin resistance, emergence and spread of colistin resistant in gram-negative bacteria pose a threat.

Effectiveness of ChAdOx1 nCOV-19 Vaccine: Experience of a tertiary care institute.

BACKGROUND: The first dose of the ChAdOx1 nCoV- 19 Corona Virus Vaccine (Covishield) was administered to the eligible beneficiaries of tertiary care institute of Western Maharashtra on 16 Jan 21 and in the past three months almost 97% of the staff has been vaccinated. The present study analyses the incidence of COVID cases in the unvaccinated and vaccinated population of the institute. METHODS: All Covid 19 infections (RT-PCR positive) from 01 February 21 to 25 April 21 were included in the study and analyzed as per their vaccination status. To assess the COVID 19 transmission in contacts, Secondary Attack Rates (SAR) of the pre-vaccination period (Jun-Oct 20) was compared with the present SAR. RESULTS: A total of 113 cases occurred in the study period (01 Feb to 25 Apr 21). Lower number of infections were observed among the fully vaccinated as compared to partially vaccinated and non-vaccinated. The overall vaccine effectiveness was found to be 88.6% (81.55-92.37) and 44.1% (4.55-67.3) in completely and partially vaccinated individuals respectively. Hazard Ratios for getting infected dropped significantly after 28 days of the second dose. The SAR in high risk contacts (HRCs) was found to be 4.25%, which was lower than SAR (20.6%) of pre-vaccination period. CONCLUSION: This is one of the earliest studies in India to report the impact of COVID-19 vaccination. The results indicate that the vaccine provides effective protection against COVID-19 infection. However, given the complex dynamics of vaccination, the role of NPIs and implementation of COVID appropriate behavior cannot be undermined.

Estimating the proportion and IgG antibody response to SARS-CoV-2 in individuals joining a central educational institute from different parts of India by Enzyme-linked immunosorbent assay (ELISA) based serology.

BACKGROUND: Antibody response to SARS-CoV may be estimated to give trends and patterns emerging in a population during an evolving epidemic. The novel coronavirus has opened a new chapter in the history of pandemics and understanding the disease epidemiology. METHODS: The study was a cross-sectional descriptive study. Institutional Ethical clearance and informed consent were taken for participation in the study. The study population included all personnel reporting to the institute for training courses, permanent posting or joining back from leave during the study period of 2 months (16 June to 16 August 2020). The sample size was calculated assuming the prevalence of COVID-19 to be 1% with the absolute precision of 0.5% and 5% level of significance, and finite correction for population size of 500, and the calculated sample size was 377. Inclusion criteria were all personnel reporting to the institute from different states and districts. Exclusion criteria-Any personnel reported for a short visit of lesser than 14 days. Demographic details and details of any likely exposure to a confirmed COVID-19 case were noted. A blood sample was collected, and serological tests were done using ErbaLisa COVID-19 IgG kit by Calbiotech, as per the manufacturer's instructions. RESULTS: Overall seropositivity of IgG COVID-19 antibodies was 7.5% (31/413) (95% CI: 5.3-10.4%). Study population (n = 413) comprised of an adult population in the age range of 21 years-53 years, and the mean age was 31.4 years (SD = 6.2 years). CONCLUSION: As the personnel joining the institute have come from various parts of the country the study provides an estimation of antibodies against COVID-19.

Blueprinting of summative theory assessment of undergraduate medical students in microbiology.

BACKGROUND: Assessment drives learning. Written assessment of many universities lacks uniformity and validation. Subjectivity influences assessment. Blueprinting has been used as content validity tools. METHODS: In this study, last 5-year's Maharashtra University of Health Sciences (MUHS) second year MBBS papers in Microbiology were evaluated for its content validity. Desired weightage to all the topics in microbiology was given by the faculty of Department of the Microbiology. University papers were also evaluated for level of cognitive domain tested. Closed ended feedback from faculty was taken and was statistically evaluated. RESULT: Study revealed both overrepresentation and underrepresentation of many topics across all the last 5-year university papers in subject of microbiology. The cognitive dimension tested in question papers as per revised Bloom's taxonomy was merely 8% from Bloom's level 1, 20% from level 2, and 8% from level 3, whereas 64% of the questions were ambiguous. Faculty feedback revealed significant impact (P < 0.05) from blueprinting in microbiology. CONCLUSION: Assessment should be aligned to learning objectives, and blueprinting improves content validity.

Immune activation markers in individuals with HIV-1 disease and their correlation with HIV-1 RNA levels in individuals on antiretroviral therapy.

BACKGROUND: Currently CD4+ T lymphocyte counts and HIV-1 RNA levels are being utilized to predict outcome of human immunodeficiency virus (HIV) disease. Recently, the role of immune activation in HIV disease progression and response to treatment is being investigated. This study focused on the expression of CD38 and HLA-DR on lymphocyte subsets in various groups of HIV-infected individuals and to determine their association with HIV-1 disease progression. METHODS: Ninety-eight cases of patients with HIV/AIDS in different disease stages and twenty-four healthy HIV-negative individuals were included in the cross-sectional study. Their immune function and abnormal immune activation markers (CD38 & HLA-DR) were detected using a flowcytometer, and HIV-1 RNA levels in individuals receiving antiretroviral drugs were estimated. RESULTS: The immune activation marker levels were significantly different between patients with different disease stages (P < 0.001). A significant negative correlation was observed between peripheral blood CD4+ T cell counts and immune activation markers. Also, a significant positive correlation was observed between HIV-1 RNA levels and CD38+CD8+ T lymphocyte. CONCLUSION: Immune activation markers (CD38 & HLA-DR) increase with disease progression. CD38+ on CD8+ T lymphocyte correlates well with HIV1 RNA levels in individuals failing on antiretroviral therapy.

Measles, mumps, and rubella: A cross-sectional study of susceptibility to vaccine-preventable diseases among young people in India.

BACKGROUND: Global elimination of vaccine preventable diseases, such as measles, mumps and rubella is a priority. Many countries have reported diminishing of antibody titres against these diseases among young population as immunization coverage of adolescents and adults in not monitored. The objective of this study was to determine the susceptibility against measles, mumps and rubella among young adults. METHODS: In this cross-sectional study serological evidence of susceptibility to measles, mumps and rubella was determined by qualitative detection of IgG antibody titres by commercially available enzyme linked florescence assay (VIDAS, bioMerieux) in serum samples young adults. RESULTS: A total of 335 young individuals (mean age: 20.54 ± 1.37 years) participated voluntarily between May 2017 to September 2018, of which 183 (54.63%) were males. Seroprotection against measles, mumps and rubella were 87.16%, 82.69% and 79.10% respectively. CONCLUSION: Serological surveillance is important to monitor immune status in population. Susceptibility of young adults to measles, mumps, and rubella indicates need for booster vaccination. With the recent launch of measles-rubella vaccination campaign in India, country specific data will be required to plan periodicity of such campaign, which in turn would be based on accumulation of susceptible individuals in a community. Lastly, inclusion of mumps vaccine in the national universal immunization program needs consideration.

Outbreak of Prototheca wickerhamii algaemia and sepsis in a tertiary care chemotherapy oncology unit.

BACKGROUND: Prototheca is an emerging, opportunistic, pathogenic, zoonotic achlorophyllous green alga, expanding in pathogenicity and host range, causing localized and disseminated infections. This outbreak of Prototheca wickerhamii algaemia and sepsis in a tertiary care 30-bedded chemotherapy oncology unit is the first human outbreak to the best of our knowledge. METHODS: P. wickerhamii algaemia was confirmed on consecutive isolation. Person to person transmission was hypothesized considering all patients in the unit at risk. Clinico-demographic, diagnostic and treatment profile were correlated. Both manual and automated systems were used for blood culture, isolation, identification and susceptibility of Prototheca. Liposomal amphotericin B was given. Outbreak surveillance of faeces, fingertips and environmental reservoirs, retrospective surveillance during past 15 years and prospective surveillance was continued for two years. RESULTS: The outbreak affected 12 neutropenic patients over 50 days. No specific clinical features were noted. The hypothesis could not be substantiated. P. wickerhamii was isolated as yeast-like colonies revealing Gram positive yeast-like cells without budding and pseudohyphae which were confirmed by automated system. Post amphotericin B blood cultures were negative for Prototheca. Surveillance studies were not contributory. CONCLUSION: P. wickerhamii has no documented reservoirs or transmission. Endogenous colonization in the gut followed by translocation during chemotherapy induced immunosuppression is likely to cause algaemia and sepsis. Outbreaks are difficult to detect and control as incubation period is variable and clinical presentation is muted, emphasizing the need to strengthen hospital and laboratory based surveillance systems to ensure adequate preparedness, rapid detection and response to outbreaks.

Molecular detection of blaNDM-1 (New Delhi metallobetalactamase-1) in nosocomial Enterobacteriaceae isolates by nested, multiplex polymerase chain reaction.

BACKGROUND: Carbapenems are considered "drugs of last resort" in many life-threatening infections. Advent of carbapenemases like KPC, OXA-48, VIM, IMP, and NDM have greatly affected the efficacy of these drugs, posing serious threat to global health and infection control. NDM bears special significance to the India subcontinent, labeled as place of origin and reservoir. NDM tends to escape detection by routine phenotypic methods, requiring molecular confirmation. This study utilizes nested, multiplex polymerase chain reaction (PCR) for reliable detection of blaNDM-1 in nosocomial Enterobacteriaceae isolates. METHODS: This study was conducted to detect prevalence of blaNDM-1, blaIMP, blaVIMand blaKPC genes by multiplex PCR among multidrug/carbapenem-resistant nosocomial Enterobacteriaceae isolates. From March 2013 to April 2014, 100 consecutive non-repeat isolates of Enterobacteriaceae from various inpatient clinical samples were analyzed. Imipenem-resistant isolates identified by Kirby Bauer disk diffusion method with Clinical and Laboratory Standards Institute guidelines were further subjected to nested, multiplex PCR to simultaneously detect blaNDM-1, blaIMP, blaVIMand blaKPC genes. RESULTS: Out of 100 isolates, 17 (17%) were found to be imipenem-resistant. blaNDM-1 was detected in all 17 isolates by nested, multiplex PCR. blaVIM was co-carried in 4 isolates while one isolate co-harbored blaIMP with blaNDM-1. Imipenem resistance and NDM-1 carriage was predominant amongst Klebsiella isolates. Maximum NDM-1 producers were isolated from the intensive care unit (70.6%). CONCLUSION: NDM-1 prevalence in nosocomial Enterobacteriaceae isolates in our hospital was found to be 17%. A nested, multiplex PCR was used for rapid detection of various carbapenemase genes with high sensitivity and specificity which is essential not only for favorable patient outcome but also for timely implementation of appropriate infection control practices to prevent further spread of such organisms.

Distribution of hepatitis B virus genotype and cancer predicting precore and basal core promoter mutations.

BACKGROUND: Chronic hepatitis B (CHB) infection which is associated with an increased risk of developing liver disease including cirrhosis and hepatocellular carcinoma. Viral factors that may increase the risk for HCC development include HBV DNA level, genotypes, and naturally occurring mutations such as hepatitis B virus precore (PC) (G1896A) and basal core promoter (BCP) A1762T/G1764A double mutations. HBV genotypes and subgenotypes can significantly influence HBeAg seroconversion rates, viremia levels, mutational patterns that could significantly influence the heterogeneity in clinical manifestations and even response to antiviral therapy. METHOD: 94 CHB infected individuals with detectable serum HBV DNA levels were studied. HBsAg, HBeAg, anti-HBc IgM antibody estimations were done by ELISA. HBV DNA estimation was done. The HBV genotypes were determined by TSP-PCR and 10 samples randomly selected for DNA sequencing. PC and BCP mutations were determined by DNA sequence analysis of core region. RESULT: Of 94 study participant samples with detectable serum HBV DNA levels, 75 were successfully genotyped and sequenced for BCP/PC region. 30/75 (40%) harbored PC and BCP mutations. The total Double mutations of BCP at A1762T/G1764A nucleotide positions, and PC mutation at G1896A nucleotide position were seen in 29.3% and 21.3%, respectively. All 75 isolates were subtype D using TSP-PCR. However, by sequencing 2/10 were subtype A, while 8 were subtype D. CONCLUSION: Our study reinforces that D is the predominant genotype in Indian population. It reveals that Indian CHB subjects have increased prevalence of BCP & PC mutations, which possibly may lead to development of HCC.

Evaluation of oxygen prescription in relation to hospital admission rate in patients with chronic obstructive pulmonary disease.

BACKGROUND: Long term oxygen therapy (LTOT) has a strong evidence base in COPD patients with respiratory failure, but prescribing practices are recognized to need reform to ensure appropriate use and minimize costs. In the UK, since February 2006, all Home Oxygen prescription is issued by hospitals, making respiratory specialists totally in charge of home oxygen prescription. It has been widely noted that inappropriate home oxygen, often for intermittent use ("short burst"), is frequently prescribed in patients with COPD and related conditions with the intention to prevent hospital admissions outside of evidence based LTOT guidelines. We participated in a national Lung Improvement Project aimed at making LTOT use more evidence based. We utilised this unique opportunity of studying the effect of removal of oxygen from COPD patients (who did not meet LTOT criteria) on hospital admission rates. METHODS: Primary and secondary care data sources were used to identify patients with COPD in a single primary care trust who were admitted to hospital at least once due to COPD between April 2007 and November 2010. Admission rates were compared between LTOT users and non-users, adjusted for age and COPD severity. LTOT users were further studied for predictors of admission in those appropriately or inappropriately given oxygen according to NICE guidance, and for admissions before and after oxygen receipt, adjusting further for co-morbidity. Mortality and economic analyses were also conducted. RESULTS: Readmission was more likely in LTOT users (3.18 v 1.67 per patient, p<0.001) after adjustment for FEV1 and age by multiple regression. When stratifying by appropriateness of LTOT prescription, adjusting also for Charlson index and other covariates, FEV1 predicted admission in appropriate users but there were no predictors in inappropriate users. In longitudinal analyses admission rates did not differ either side of oxygen prescription in appropriate or inappropriate LTOT users. Specialist assessment resulted in cost savings due to reduced use of oxygen. CONCLUSIONS: Admission to hospital is more likely in LTOT users, independent of COPD severity. Oxygen use outside NICE guidance does not appear to prevent admissions.

Seroprevalence of human parvovirus B19 in healthy blood donors.

BACKGROUND: Human parvovirus B19 is an emerging transfusion transmitted infection. Although parvovirus B19 infection is connected with severe complications in some recipients, donor screening is not yet mandatory. To reduce the risk of contamination, plasma-pool screening and exclusion of highly viraemic donations are recommended. In this study the prevalence of parvovirus B19 in healthy blood donors was detected by ELISA. METHODS: A total of 1633 samples were screened for IgM and IgG antibodies against parvovirus B19 by ELISA. The initial 540 samples were screened for both IgM and IgG class antibodies and remaining 1093 samples were screened for only IgM class antibodies by ELISA. RESULTS: Net prevalence of IgM antibodies to human parvovirus B19 in our study was 7.53% and prevalence of IgG antibodies was 27.96%. Dual positivity (IgG and IgM) was 2.40%. CONCLUSION: The seroprevalence of human parvovirus B19 among blood donor population in our study is high, and poses an adverse transfusion risk especially in high-risk group of patients who have no detectable antibodies to B19. Studies with large sample size are needed to validate these results.