Immunogenicity and safety of heterologous boost immunization with PastoCovac Plus against COVID-19 in ChAdOx1-S or BBIBP-CorV primed individuals.

BACKGROUND: This study aimed at evaluation and comparison of PastoCovac Plus protein-subunit vaccine in parallel with ChAdOx1-S (AstraZeneca) and BBIBP-CorV (Sinopharm) in primarily vaccinated volunteers with two doses of ChAdOx1-S or BBIBP-CorV. MATERIALS AND METHODS: 194 volunteers enrolled the study who were previously primed with 2 doses of ChAdOx1-S or BBIBP-CorV vaccines. They were divided into two heterologous regimens receiving a third dose of PastoCovac Plus, and two parallel homologous groups receiving the third dose of BBIBP-CorV or ChAdOx1-S. Serum samples were obtained just before and 4 weeks after booster dose. Anti-spike IgG and neutralizing antibodies were quantified and the conventional live-virus neutralization titer, (cVNT50) assay was done against Omicron BA.5 variant. Moreover, the adverse events data were recorded after receiving booster doses. RESULTS: ChAdOx1-S/PastoCovac Plus group reached 73.0 units increase in anti-Spike IgG rise compared to the ChAdOx1-S/ ChAdOx1-S (P: 0.016). No significant difference was observed between the two groups regarding neutralizing antibody rise (P: 0.256), indicating equivalency of both booster types. Adjusting for baseline titers, the BBIBP-CorV/PastoCovac Plus group showed 135.2 units increase (P<0.0001) in anti-Spike IgG, and 3.1 (P: 0.008) unit increase in mean rise of neutralizing antibodies compared to the homologous group. Adjustment for COVID-19 history, age, underlying diseases, and baseline antibody titers increased the odds of anti-Spike IgG fourfold rise both in the ChAdOx1-S (OR: 1.9; P: 0.199) and BBIBP CorV (OR: 37.3; P< 0.0001) heterologous groups compared to their corresponding homologous arms. The odds of neutralizing antibody fourfold rise, after adjustment for the same variables, was 2.4 (P: 0.610) for the ChAdOx1-S heterologous group and 5.4 (P: 0.286) for the BBIBP CorV heterologous groups compared to their corresponding homologous groups. All the booster types had the potency to neutralize BA.5 variant with no significant difference. The highest rate of adverse event incidence was recorded for ChAdOx1-S homologous group. CONCLUSIONS: PastoCovac Plus booster application in primed individuals with BBIBP-CorV or ChAdOx1-S successfully increased specific antibodies' levels without any serious adverse events. This vaccine could be administrated in the heterologous regimen to effectively boost humoral immune responses.

The impact of ABO blood types on humoral immunity responses and antibody persistency after different COVID-19 vaccine regimens.

This study evaluated the possible effects of blood types on coronavirus disease (COVID-19) vaccine immunogenicity and antibody (Ab) persistency. Five different vaccinated groups against COVID-19 were investigated at Pasteur Institute of Iran from April 2021 to December 2022. Anti-Spike IgG and neutralizing Ab rise were tracked on Day 21 as well as the humoral immune persistency assessment 180 after booster shots. Late adverse events up to 6 months after the booster dose were collected. The results showed that blood type A, led to a significantly higher anti-Spike Ab rise in AstraZeneca primed recipients in comparison with Sinopharm primed ones in heterologous regimens (p: 0.019). Furthermore, blood type O was a great co-effector in homologous AstraZeneca recipients regarding neutralizing Ab rise (0.013). In addition, blood type O led to a better anti-Spike Ab persistency in the Sinopharm homologous group whereas type A had the best effect on neutralizing Ab durability in the same vaccine group. What is more, Rh-positive individuals in AstraZeneca + PastoCovac Plus group had a higher rate of anti-Spike Ab rise (p = 0.001). Neutralizing Ab rise was also induced in AstraZeneca homologous and heterologous regimens of Rh-positive individuals significantly higher than Sinopharm primed cases. The present study showed the potential impact of blood types A/O and Rh-positive on a better humoral immune responses and Ab persistency. It is proposed that blood type A and Rh-positive could increase the Ab rise in AstraZeneca vaccinated individuals. Moreover, blood type O might be a better co-effector of anti-Spike Ab persistency in Sinopharm recipients.

Characterization of long COVID-19 manifestations and its associated factors: A prospective cohort study from Iran.

The prevalence and variety complaints of COVID-19 cases in a long term have been investigated in recent studies. The symptoms over the time are various and unpredictable which may persist several weeks after full recovery. The importance of long-COVID-19 manifestations includes its effect on the recovered cases which requires a rational management based on an accurate guideline to handle post-acute COVID-19 state. The aim of this study was to evaluate the incidence of post-acute COVID-19 syndrome and to identify the associated risk factors as well as to compare new and persistent symptoms at different post-acute phases. Totally 254 individuals from Pasteur Institute of Iran (or/and their relatives) were investigated who had a previously confirmed COVID-19 PCR test. The long-term manifestations of the virus were categorized through a time window as acute, ongoing, post-COVID and persistent phases and the individuals were assessed by the face-to-face or the phone call interview according to their complaints. The data were then statistically analyzed to determine the frequency of the symptoms and also the associated factors in which a p value < 0.05 was considered significant. Except a small asymptotic group of five, 249 cases progressed the symptoms to acute phase among which 64.1% reported at least one symptom in post-acute phase. Neurological sequelae were found as the most frequent symptom (91.6%). Furthermore, there was a significant association between the underlying diseases, age and acute phase symptoms to the post-acute phase syndrome susceptibility (p < 0.05). In conclusion, the increasing number of the reports and studies on long COVID-19 which can hugely affect the life quality should be more investigated and explored in terms of the pathophysiology to achieve appropriate treatments in time. The clusters of symptoms, specially a combination of neurological signs, presenting over months after the recovery impose a huge difficulty to the recovered population.

Manifestations, complications, and treatment of neurobrucellosis: a systematic review and meta-analysis.

PURPOSE: Central nervous system involvement by Brucella species is the most morbid form of brucellosis disease. Studies on neurobrucellosis are scarce and limited to case reports and series. Brucella is unable to infect or harm neurons without the assistance of monocytes. This raises the question of whether ceftriaxone-based regimens are effective. METHODS: The primary aim of this study was to identify, evaluate, and summarize the findings of all relevant individual studies in the past 30 years to help better understand the disease. To achieve this, a broad systematic search was undertaken to identify all relevant records. Epidemiological and clinical features of the disease were assessed by the pooled analysis of descriptive studies. Through a meta-analysis, the treatment period duration was compared between the ceftriaxone-based and oral regimens using Standardized mean differences to measure effect size. RESULTS: 448 patients were included in the Meta-analyses from 5 studies. A moderate positive effect was found for ceftriaxone-based regimens over oral treatments, and there was a significant difference between these two groups (SMD 0.428, 95% CI -0.63 to -0.22, I 2 = 37.64). Neurobrucellosis has a different clinical picture in pediatric patients. The disease is less chronic in children. Fever, nausea and vomiting, fatigue, and abdominal pain were significantly more prevalent symptoms in children, and Convulsions, ascites, sensorineural hearing loss, and papilledema were significantly more prevalent signs in children than adults. CONCLUSION: It is recommended to initiate the treatment of neurobrucellosis with IV ceftriaxone therapy in combination with oral therapy.

SARS-CoV-2 re-infection rate in Iranian COVID-19 cases within one-year follow-up.

Since the COVID-19 pandemic initiation, the possibility of re-infection has been unclearly present. Although herd immunity has a potential reliance through natural infection, human corona viruses has the ability to subvert immunity and re-infection happens for seasonal corona viruses. Currently, the frequency of SARS-CoV-2 re-infection incidence is not exactly defined. In this study we aimed at determination of SARS-CoV-2 re-infection rate in Iranian population. In a total of 5696 COVID-19 suspicious individuals, RT-PCR was applied to diagnose the infection. The confirmed patients were followed for 12 months and serology tests were applied to measure the specific antibodies. Among 1492 confirmed COVID-19 cases, five individuals experienced the subsequent infection. The re-infection/reactivation incidence rate was totally 0.33% after one year of follow-up. The interval ranged from 63 to 156 days. All the cases had viral mutations in the second episode of the infection. All of them were symptomatic cases with moderate severity. The estimated rate of SARS-CoV-2 in Persian population is therefore rare and natural infection seems to induce good protection against re-infection which clarifies that mass vaccination can hugely affect the society.

Clinical characteristics of SARS-CoV-2 by re-infection vs. reactivation: a case series from Iran.

COVID-19 immunity in infected individuals may not be persistent. The specific response wanes in patients who have recovered from this infection. Nevertheless, it has not been fully understood whether true re-infection occurs or the viral reactivation. In this study, we investigated three COVID-19 patients who represented the symptoms after recovery. Chest CT scan was applied to assess the patients along with the viral samples from oropharyngeal/nasopharyngeal which were subjected to RT-PCR. The viral genome sequencing was applied where possible to distinguish possible re-infection or latent reactivation. Moreover, COVID-19-specific antibodies available data were evaluated in each incidence. The second episode of SARS-CoV-2 infection was different among the investigated subjects who experienced an interval between positive PCR tests ranged between 63 and 156 days. The disease presentation was less or more severe in the second infection. All cases were found IgG positive in the re-infection phase. The sequencing of SARS-CoV-2 sample obtained from two cases revealed a D614G mutation of S gene from the second isolated sample strengthens the case for the re-infection. The possibility of re-infection and reactivation could have significant effect on clinical implications and also vaccination. Our data supports clear warning of SARS-CoV-2 continuous circulation potency among the populations in spite of herd immunity either with natural infection or vaccination. This issue is critical in term of the patients, clinical investigate, and viral transmission.

SARS-CoV­2, a virus with many faces: a series of cases with prolonged persistence of COVID-19 symptoms.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), as the causative agent of the ongoing pandemic, has spread into more than 200 countries to date. The disease which is caused by the virus is termed COVID-19. In most cases, it presents at first like common flu with cough and other respiratory symptoms. Nevertheless, other symptoms have been reported, such as a feeling of extreme fatigue, gastrointestinal symptoms, or acute onset of olfactory and gustatory dysfunction. Here we report a series of 10 cases (1 male, 9 females) observed between February and April 2020, with an undulating appearance and disappearance of symptoms. Weeks passed before the diagnosis was established. Symptoms resolved rapidly after treatment with hydroxychloroquine. It seems that the course of COVID-19 can be mild or moderate but with a long persistence of symptoms, and may therefore remain obscure. This may cause a public health issue because of the long infectivity of these patients.

Epidemiologic and clinical findings of children with acquired immunodeficiency syndrome in four provinces of Iran.

INTRODUCTION: The human immunodeficiency virus (HIV) is still a remarkable challenge throughout the world, especially in developing countries. Despite the fact that HIV in children is becoming one of the most challenging diseases, it seems that pediatric AIDS in Iran is an unknown disease and there is a lack of studies about it. The aim of this study was to describe the characteristics of HIV-positive children who referred to the hospitals of Tehran, Kermanshah, Kurdistan, and Qom provinces of Iran. MATERIALS AND METHODS: This study was a retrospective investigation of medical records among 61 children with a diagnosis of HIV who were admitted to the children's hospitals in the four provinces of Iran during a 3-year period (2013-2016). RESULTS: The frequency of HIV in the center of Iran (Tehran and Qom provinces) was higher (N = 37, 61%). Most of the infected patients were between 5 and 15 years old, 52% were male, and 93% had a history of HIV in their family. Median age at diagnosis of HIV was 2 years. Most of the hospitalized patients were discharged and only two patients (3%) died due to HIV infection. The vast majority of patients (93%) were infected through maternal transmission and a low percentage (29%) were diagnosed before 1 year of age. All of them were in the third stage of the disease. All patients had a positive HIV PCR test. HIV EIA was positive in the majority of cases (98%). A history of addiction in the family was demonstrated in 22 cases (36%). Weight loss (N = 51, 84%), prolonged fever (N = 50, 81%), and respiratory infection (N = 26, 47%) were the most common symptoms. CONCLUSION: This study demonstrated a high frequency of pediatric HIV among children aged 5-15 years in four provinces of Iran. Novel strategies to prevent and eliminate mother-to-child transmission of HIV, diagnostic facilities, and treatment of infected mothers during pregnancy in our country are highly recommended.

No evidence of occult HBV infection in population born after mass vaccination.

Despite access to efficient hepatitis B virus (HBV) vaccine and universal immunization schedules, HBV infection remains a global health concern. HBV infection has decreased by this program. Nevertheless, breakthrough infections occur due to generation of occult HBV infection (OBI) and surface gene mutants in the immunized population. We aimed to determine the presence of OBI in a population born after initiation of nationwide HBV vaccination in Tehran, Iran. A HBV mass vaccination schedule was launched in Iran in 1993. For this study, we enrolled 1120 cases younger than 24 years. ELISA was applied to evaluate the presence of HBsAg, anti-HBs and anti-HBc. HBV-DNA presence was determined in all HBsAg-negative cases using nested polymerase chain reaction. The prevalence of HBsAg, anti-HBc and anti-HBs was 0.1, 0.54 and 39.9% respectively. Out of 6 anti-HBc-positive individuals, 4 cases also had anti-HBs. One case revealed HBsAg co-existence and the other one showed isolated anti-HBc. HBV-DNA was not detected in HBsAg-negative specimens. A very low prevalence of HBsAg and isolated anti-HBc was observed and no occult HBV infection was detected. It seems that evasion mutants are not a potential threat for HBV universal immunization efficacy in the vaccinated population.

Significance of serum antibodies against HPV E7, Hsp27, Hsp20 and Hp91 in Iranian HPV-exposed women.

BACKGROUND: Among different types of human papillomavirus (HPV), types 16 and 18 were known to be high-risk agents causing mainly cervical cancer. Up to now, the potential of HPV E7 protein has been proved as a diagnostic marker of cervical cancer. Moreover, the levels of anti-heat shock protein (Hsp) and anti-high mobility group box-1 (HMGB1) antibodies in cancer patients have been useful in tumor diagnosis. The goal of the present study was to determine the efficiency of the potential serologic markers including HPV E7, Hsp20, Hsp27 proteins and Hp91 peptide in Iranian HPV-exposed women, for the first time. METHODS: At first, the recombinant HPV E7, Hsp20 and Hsp27 proteins were expressed in E. coli system, and purified by affinity chromatography under native conditions. Then, antibody responses were detected against the recombinant proteins as well as Hp91 peptide as potential markers in 49 Iranian women who were seropositive for HPV-16 and 18 L1 capsids (i.e., HPV-exposed women) and 49 controls using indirect ELISA. RESULTS: Our data indicated that the seroreactivities of women exposed to HPV16, HPV18 and both of them against the recombinant E7, Hsp20, Hsp27 proteins and Hp91 peptide were significantly higher than those in control group (p < 0.05 for HPV16 or HPV18; p < 0.01 for both of them versus all markers). HPV-exposed women with high antibody responses to HPV-16 and 18 L1 capsids as a commercial biomarker had significant seroreactivity to HPV-16 and 18 E7 and Hsp27 (p < 0.05). The recombinant E7 and Hsp27 proteins showed higher efficiency than Hsp20 and Hp91 for detection of individuals exposed to HPV infections (p < 0.05). CONCLUSION: Generally, the levels of serum E7 and Hsp27 were increased in HPV-16 and 18 L1- seropositive women suggesting their potential value as a diagnostic marker for HPV infections.

Seroprevalence, molecular epidemiology and quantitation of parvovirus B19 DNA levels in Iranian blood donors.

Human parvovirus B19 (B19) infection is common among blood donors, and healthy blood donors can transmit virus via transfusion. Due to resistance of B19 to viral inactivation methods, there is a potential concern regarding transfusion safety in blood products. We aimed to determine the seroprevalence, molecular epidemiology, and quantitation of B19 DNA levels in blood donors in Tehran, Iran. A total of 500 blood donors from Blood Transfusion Research Center were studied. ELISA was used for detection of B19 IgG and IgM and nested PCR was carried out for detection of B19 DNA. PCR products were subjected to direct sequencing. B19 viral load was determined by real time PCR. B19 IgG, IgM, and DNA were detected in 27.6, 2.6, and 1.2% of donors respectively. Ten samples (2%) were positive for both antibodies while in four cases (0.8%), B19 IgG and DNA detected simultaneously. One case had B19 IgM, IgG, and viremia concurrently. The titers of B19 DNA in four of six donors were more than 106 IU/mL (high level viremia) and all four cases had IgG simultaneously. All B19 isolates categorized in genotype 1A. Our findings indicated that prevalence of B19 DNA in Iranian blood donors was comparable with previous studies throughout the world. High level B19 viremia found in 0.8% of our donors and all viremic donors revealed neutralizing B19 antibody. Therefore implementation of a B19 screening test for each volunteer blood donor does not appear to be necessary but B19 testing for plasma-derived products seems important in Iranian donors.

Reduction toxicity of Amphotericin B through loading into a novel nanoformulation of anionic linear globular dendrimer for improve treatment of leishmania major.

Amphotericin B (A) as an antileishmanial drug has limited clinical application owing to severe side-effects and low-water solubility. This is the first study reported using Anionic Linear Globular Dendrimer (ALGD) as A carrier for the increase of A solubility rate, decrease its toxicity, and improve its therapeutic effects. ALGD was synthesized and A was loaded into nanoparticles for the first time with the drug-loading efficiency of 82%. Drug loading was confirmed using characterization methods. The drug solubility rate was increased by 478-folds. The results of the study showed that the A toxicity was significantly decreased by 95% in vitro and in vivo environments, which was confirmed by pathology findings and enzymatic evaluation. Furthermore, the nanodrug caused that mortality rate was reached to zero. Moreover, the nanodrug was as potent as the free drug and glucantime (GUL) in reducing the parasite burden and parasite number. These findings indicated the potency of ALGD to decrease the drug side-effects, increase the drug solubility rate, and improve the drug efficacy. Moreover, the nanoformulation was a non-toxic and cost-effective formulation. The conformity between in vitro and in vivo results suggested that the A-loaded ALGD could be considered as a promising candidate in reducing the side-effects of A in leishmaniasis treatment.

Prevalence and antimicrobial susceptibility of Salmonella and Shigella spp. among children with gastroenteritis in an Iranian referral hospital.

BACKGROUND: Gastroenteritis is one of the leading cause of illnesses through the world, especially in developing countries.Salmonella and Shigella infections are considered as the main public health problems in children. The aim of this study was to detect the prevalence and antimicrobial susceptibility of Salmonella and Shigella spp. among children with gastroenteritis in an Iranian referral hospital. METHODS: During April 2013 to April 2014, all medical records of children with gastroenteritis admitted to a pediatric medical center were evaluated. Positive stool cultures of children were evaluated and frequency of Salmonella and Shigella spp. and their antimicrobial susceptibility were detected. RESULTS: In this study, 676 patients with the mean age of 24.94 months were enrolled. Eighty-eight (42%) Salmonella spp., 85 (40%) Shigella spp., 33 (16%) E. coli and 5(2%) candida albicans were isolated from 211 positive stool cultures. Among 85 Shigella spp. isolates, S. sonnei, S. flexneri and other Shigella spp. were isolated from 39 (46%) isolates, 36(42%) and 10(12%), respectively. Among 88 isolated Salmonella spp., 36 (41%) isolates were Salmonella Serogroup D, 26 (30%) were Salmonella Serogroup B, 20 (23%) isolates were Salmonella Serogroup C and 6 (7%) were other Salmonella spp. isolates. Thirty-eight percent of Salmonella serogroup B were resistant to nalidixic acid, while higher frequency of nalidixic acid resistant was found in Salmonella serogroup C and Salmonella serogroup D. The higher frequency of ampicillin resistant was found in Shigella spp. than Salmonella spp. High frequency of cefotaxime resistant was seen in S. sonei and S. flexneri (77% and 56%, respectively), whereas more than 90% of Salmonella serogroup B, C and D were susceptible to this antibiotic. CONCLUSION: In conclusion, Shigella and Salmonella serogroups can be considered as important etiological agents of acute diarrhea in children. Since the prevalence of antibiotic resistance is increasing in recent years in Iran, further studies on the prevalence, antimicrobial susceptibility pattern and mechanisms of antibiotic resistance in these species is highly recommended.

Gender and age-specific seroprevalence of human papillomavirus 16 and 18 in general population in Tehran, Iran.

The assessment of the gender and age-specific seroprevalence of human papillomavirus (HPV) is essential for planning of HPV vaccine implementation into the preventive programs. In this study, we aimed to determine the age-specific seroprevalence of HPV-16 and 18 in both males and females in Tehran, Iran. Three hundred and seventy-eight women (10-35 years) and 162 men (10-25 years) from Tehran, Iran, were enrolled. Anti-HPV IgG antibodies against HPV-16 and HPV-18 were detected by ELISA using papillomavirus type 16 and 18 L1-capsids as antigen. HPV-16 antibody was detected in 15.6 and 13.6% of women and men, respectively. Antibody against HPV-18 was found positive in 12.7 and 8% of women and men, respectively. The highest seroprevalence of HPV-16 and 18 were seen in women aged 26-30 years (22.2 and 19.4%, respectively), and the lowest HPV-16 and 18 seropositivity rates were seen in males and females aged 10-15 years (9.3 and 1.9%, respectively). In our cohort of study, in males, both anti-HPV-16 and 18 increased after age 15 years, peaking in men aged 21-25 years. In women, both HPV-16 and 18 seropositivity increased after 15 years, declined at 21-25 years, peaked in women aged 26-30 years and again decreased after 30 years. Our data showed increasing exposure rate to high-risk HPV vaccine types in our studied population over 15 years of age. In order to prevent the HPV-related cancers, implementation of HPV vaccine into the national immunization program in Iran and vaccination of females and males less than 15 years of age are suggested.

Epidemiology of children with acquired immune deficiency syndrome (stage 3): A referral hospital-based study in Iran.

Lack of recognition of human immunodeficiency virus (HIV) infection especially in children and delayed implementation of effective control programs makes HIV infection as a major cause for concern. Information on HIV epidemiology in Iran as well as other Islamic countries is limited. The aim of our study was to describe the clinical manifestation and laboratory finding of HIV infected children who were admitted to a referral Children Medical Center (CMC) in Tehran, Iran, during 11 years from January 2002 to January 2013. This was a retrospective study carried out over a period of 11 years. The records of all patients attending to the CMC with confirmed acquired immunodeficiency syndrome (AIDS) were screened. The patients were evaluated for social circumstance, family history, age, gender, clinical, and laboratory features. Clinical data including fever, respiratory distress, diarrhea, rash, etc. as well as laboratory tests including complete blood count, serum glucose level, electrolytes, liver function test, cultures, CD4 lymphocyte count were evaluated. During the study period, 32 HIV positive children were enrolled. The majority of patients were presented with weight loss, prolonged fever, respiratory infection and chronic diarrhea. In this study, salmonella infections as well as streptococcal pneumonia and candida infections followed by, tuberculosis and Pseudomonas aeruginosa infections were the predominant opportunistic infections. Since the number of HIV-positive children has been alarmingly increasing in recent years and perinatal transmission is the most common route of HIV infection in children, essential recommendations for prenatal HIV testing as well as appropriate antiretroviral therapy by HIV infected mothers are needed.

Frequency and subtype of BK virus infection in Iranian patients infected with HIV.

Human polyomavirus BK virus (BKV) is a double-stranded DNA virus that infects approximately 90 % of the general population as a subclinical or mild infection. In immunosuppressed patients, such as HIV cases, BKV may be reactivated resulting hemorrhagic cystitis and tubulointerstitial nephritis. However, there are limited studies on prevalence and molecular epidemiology of BKV in Iran. We therefore aimed to evaluate the prevalence and subtypes of BKV in Iranian HIV patients. A total of 99 patients with HIV infection were enrolled in the study. Presence of BKV DNA in plasma was evaluated by nested PCR. PCR products were sequenced directly, and phylogenetic analysis was performed. BKV DNA was detected in 8.08 % of HIV patients. BKV viremia presented in 4 out of 25 patients (16 %) not receiving antiretroviral therapy in comparison with 4 out 74 of HAART-treated patients (5.4 %) (P = 0.023). In patients with CD4 counts ≥200 cells/mm(3), viremia was found more commonly (7/80 = 8.8 %) than in those with lower counts (1/19 = 5.2 %) (not significant). All sequenced BKV isolates belonged to subtype Ib-2. Our findings indicated that the prevalence of BKV viremia is relatively prevalent in patients with HIV infection and significantly higher in naïve than HAART-treated cases. Therefore, HAART can eliminate BKV infection from plasma and reduce viremia although the actual implication of BKV viremia in HIV patients is not clear.

Frequency and Genotype of Human Parvovirus B19 among Iranian Hemodialysis and Peritoneal Dialysis Patients.

OBJECTIVES: The aim of this study was to evaluate the frequency and genotype of human parvovirus B19 and its relation with anemia among Iranian patients under dialysis. METHODS: Fifty hemodialysis (HD) and 33 peritoneal dialysis (PD) patients were enrolled. B19 IgG and IgM antibodies were assessed by ELISA, and the presence of B19 DNA was evaluated by nested PCR. PCR products were sequenced directly and phylogenetic analysis was performed. RESULTS: In the HD group, the prevalence of B19 antibodies was 54% for IgG and 4% for IgM. B19 DNA was detected in 10% of the cases, and 10% showed B19 IgG and viremia simultaneously. In the PD group, the prevalence of B19 IgG and IgM was 57.6 and 0% respectively, whereas B19 DNA was found in 12.1% of the group. A total of 9.1% showed B19 IgG and viremia concurrently. There was no significant difference regarding anemia and B19 infection in either group. All B19 isolates were clustered in genotype 1A. CONCLUSION: Our findings indicate that B19 infection plays no role in leading chronic anemia in dialysis patients. However, persistent B19 viremia and the circulation of the same strains in dialysis patients may indicate a potential risk for the contamination of dialysis equipment and nosocomial spread of B19 infection within dialysis units.

No evidence of persistent parvovirus B19 viremia among Iranian patients with HIV after a 1-year follow-up.

Recent studies have demonstrated that, in common with other latent viruses, parvovirus B19 infection can be controlled by the host immune response but may persist in some places such as the bone marrow. Persistent B19 infection has been found in both immunocompetent and immunocompromised individuals, such as patients infected with human immunodeficiency virus (HIV). However, there is limited data regarding long-term B19 viremia in HIV patients. In this study, we investigated virological and hematological findings, and also the clinical outcome, of seven cases of HIV/B19 coinfection (confirmed by PCR) after one year. These cases were provided from a previous study on patients with HIV infection that found B19 DNA in 13 cases. Seven of these 13 patients were available after 1 year, and we retested them for B19 viremia and B19-specific antibodies. B19 IgG was tested by ELISA, and B19 DNA was assessed by nested PCR. Anemia was not observed in these cases. All subjects had cleared viremia, but B19 IgG seroconversion occurred in two cases. No significant changes in CD4 and hemoglobin occurred. The results of this study indicate that B19 infection in HIV patients is a subtle infection and that B19 viremia is not a long-term event.

Low prevalence of hepatitis B vaccine escape mutants among individuals born after the initiation of a nationwide vaccination program in Iran.

A nationwide hepatitis B virus (HBV) vaccination program for neonates was launched in Iran in 1993. Despite the success of this program, concern about its long-term success still remains, because breakthrough infections due to emergence of surface mutants have been reported in immunized children. We aimed to evaluate the seroprevalence of HBV and vaccine escape mutants among individuals born after the initiation of the nationwide vaccination program in Iran. This study included 1115 participants younger than 23 years old, with 223 in each age cohort. The presence of HBsAg, anti-HBs and anti-HBc was evaluated using an ELISA kit. HBV-DNA levels were measured in anti-HBc and/or HBsAg-positive subjects. PCR products were sequenced and mutations were identified. The overall HBsAg prevalence was 0.27 %. Anti-HBs and anti-HBc positive rates were 48 % and 0.18 %, respectively. Two individuals were positive for anti-HBc, one of whom was also positive for HBsAg, and the other was positive for anti-HBc only. HBV DNA was detected in three out of four anti-HBc-and /or HBsAg-positive subjects. An I195M mutation within the S gene was detected in two of the three HBV-DNA-positive cases. A very low prevalence of HBsAg and isolated anti-HBc were found in this study. The I195M mutation found in the surface gene could have been induced by immune pressure. Although the number of ''vaccine escape'' mutants found in this cohort was low, ongoing surveillance of breakthrough infections and escape mutants is still needed.