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Introduction: parvovirus B19 (B19V) infection during pregnancy can be transmitted to the fetus and cause serious complications such as fetal hydrops and stillbirth. The preexistence of specific IgG prevents vertical transmission. Seroprevalence in fertile age is variable (50-70%) and depends on the region/viral circulation, in addition to factors such as maternal age and frequent exposure to children., Objectives: to determine seroprevalence for B19V in pregnant women at Hospital Universitario de Maternidad y Neonatología (HUMN), analyze its association with predictive factors and describe cases of B19V infection., Methods: observational, cross-sectional study. Patients treated at HUMN during 2021-2022 were included and compatible demographic and clinical data were recorded. Specific IgG was quantified and its association with predictive factors was analyzed by bivariate analysis (p<0.05). In cases with signs/symptoms associated with B19V, specific IgM and viral DNA were also determined. Results: 317 cases were studied and anti-B19V IgG was detected in 214/317 (67.5%). No association was found between seroprevalence and maternal age, multiparity, cohabitation with children under 15 years of age, or presence of maternal/fetal signs/symptoms. Ten cases (10.4%) of B19V infection were identified, all of them with anemia and one with fetal hydrops and VDRL+., Conclusion: in the population studied, B19V seroprevalence for was 67.5% and independent of the predictive factors, leaving 32.5% without evidence of exposure to the virus (susceptible to contracting the infection in the future). The detection of infection in symptomatic cases indicates the importance of investigating B19V in this group., (Universidad Nacional de Córdoba)

Background: Parvovirus B19 (B19 V) infection during pregnancy can cause adverse fetal outcomes. Our aim was to characterize both clinical and asymptomatic maternal and neonatal cases by studying virological and serological markers of B19 V infection, and to sequence the complete genome of the circulating virus in Argentina., Methods: Symptomatic patients were included based on maternal and/or fetal-neonatal signs attributable to B19 V infection during gestation. Pregnant patients were analyzed in either the timely diagnosis group (TD, samples obtained when symptoms were present and infection was suspected) or the retrospective diagnosis group (RD, samples collected immediately postpartum), and newborns were analyzed at birth. A sample of asymptomatic individuals was also analyzed. Diagnostic tests (PCR/qPCR/serology) and sequencing were performed on archived serum samples from 2018 to 2023, and clinical data were obtained from medical records., Results: We studied 328 symptomatic patients, including 185 pregnant patients (73 TD and 112 RD) and 143 newborns. Among them, we identified 27/328 (8.2 %) positive cases (B19V+): 12/73 (16.4 %) in the TD group, 6/112 (5.4 %) in the RD group, and 9/143 (6.3 %) newborns. Within the 77 mother-newborn pairs included, there were 8 (10.4 %) B19 V infections and 6 cases of vertical transmission. Additionally, B19 V infection was detected in 26/310 (8.4 %) asymptomatic patients. Phylogenetic analysis identified genotype 1a as a circulating strain in Argentina., Conclusions: Our findings highlight the need to raise awareness and enhance diagnostic approaches in Argentina to more effectively identify and manage B19 V infections during pregnancy in our region., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2024. Published by Elsevier B.V.)

Non-immune hydrops fetalis represents a diagnostic challenge in high-risk pregnant women. Vertical infection with human parvovirus B19 (B19V) is a possible cause. National guidelines propose maternal serologic screening (IgG/IgM), which may be insufficient in some situations. We report a case of vertical B19V infection with difficulties in prenatal diagnosis. Preterm newborn, normal weight (2950 g), born to a 30-year-old mother with anemia and hydrops fetalis (week 17). Cardiac, chromosomal, isoimmunization-Rh, and usual infectious causes (TORCH) were ruled out. Maternal serology for B19V showed IgG+ and IgM-, and the diagnosis was dismissed. The newborn presented abdominal distension (ascites), anemia, and jaundice. Postnatal results confirmed the diagnosis with DNA+ for B19V. Discharge at 17 days with good evolution. The protocol for B19V screening in vertical infection needs to be revised by incorporating early molecular studies (PCR) from the early stages of gestation to optimize the diagnosis and treatment of patients with this congenital infection., (Sociedad Argentina de Pediatría.)

We determined anti-rubella and anti-measles immunoglobulin G (IgG) in 7- to 19-year-old children and adolescents with vaccine only-induced immunity of Córdoba, Argentina, during a 6-month period over 2021-2022. Of the 180 individuals studied, 92.2% and 88.3% were positive for anti-measles and anti-rubella IgG, respectively. No significant differences were found comparing anti-rubella IgG concentrations ( p  = 0.144) and anti-measles IgG concentrations ( p  = 0.105) of individuals classified by age, but anti-measles IgG and anti-rubella IgG levels were significantly higher among female individuals compared with males ( p  = 0.031 and p  = 0.036, respectively). Female subjects in the younger age group had higher concentrations of anti-rubella IgG as well ( p  = 0.020), even when anti-measles IgG concentrations did not differ among female age-subgroups ( p  = 0.187). In contrast, age subgroups of male individuals did not have significantly different IgG concentrations for rubella ( p  = 0.745) or measles ( p  = 0.124). Among samples with discordant results (22/180, 12.6%), 9.1% were negative for rubella but positive for measles; 13.6% were equivocal for rubella and positive for measles; 22.7% were equivocal for rubella and negative for measles, while 54.5% were positive for rubella but negative for measles. The findings indicate a seroprevalence below recommended for preventing measles in the population studied, while they evidence the need for standardization of serological tests for rubella IgG.

Introduction. Human bocavirus 1 (HBoV1) infection occurs with viral genome presence in respiratory secretions (RS) and serum, and therefore both samples can be used for diagnosis. Gap statement. The diagnostic sensitivity of HBoV1 DNA detection in serum and the duration of DNAaemia in severe clinical cases have not been elucidated. Aim. To determine HBoV1 DNA in serum and RS of paediatric patients hospitalized for lower acute respiratory infection (LARI) and to analyse the clinical-epidemiological features of positive cases. Methodology. This was a prospective, transverse study. Physicians selected the clinical situations and obtained paired clinical samples (RS and serum) that were tested by PCR/qPCR for HBoV1. Positive cases were analysed considering time of specimen collection, co-detection, clinical manifestations and viral load; statistical significant level was set at α=0.05. Results. HBoV1 was detected in 98 of 402 cases included (24 %); 18/98 (18 %) patients had the virus detectable in serum and 91/98 (93 %) in RS ( P <0.001). Positivity rates were not significantly different in patients with RS and serum collected within or beyond 24 h of admission. Single HBoV1 infection was identified in 39/98 patients (40 %), three patients had HBoV1 in both clinical samples (3/39, 8 %) and 32 (32/39, 82 %) only in RS, 22 of them (69 %) with both clinical samples within 24 h of admission. Cough ( P =0.001) and rhinitis ( P =0.003) were significantly frequent among them and most patients were diagnosed with bronchiolitis (22/39, 56 %) and pneumonia (9/39, 23 %), which was more frequent compared to cases with co-infection ( P =0.04). No significant differences were identified among patients with high, medium or low viral load of HBoV1 regarding rate of positivity in both clinical samples, the time of collection of RS and serum, co-detection, first episode of LARI, clinical manifestations, comorbidity or requirement for assisted ventilation. Intensive care unit (ICU) patients had a significantly higher frequency of detection ( P <0.001) and co-detection ( P =0.001) compared to patients on standard care. Conclusions. HBoV1 is prevalent among infant patients hospitalized for LARI and including it in the standard testing can add to the aetiological diagnosis in these cases, especially for patients admitted to the ICU. HBoV1 detection in serum did not contribute significantly to the diagnosis as compared to detection in respiratory secretions.

A retrospective, cross-sectional study was conducted to determine the frequency of human parvovirus B19 (B19V) infected individuals, viral loads and immunity among blood donors from Argentina, in a post-epidemic outbreak period. B19V DNA and specific IgG were tested in minimum study samples of donors attending a blood bank at Córdoba, Argentina, in 2014. Anti-B19V IgM and viral loads were determined in B19V-positive plasma samples. Seven of 731 samples (0.96%) resulted positive, corresponding to individuals aged 32-53 years, four of them repeat donnors and three first-time donors. Viral loads were <10 3 IU/mL. None had IgM and 6/7 had IgG, one of them at a high level (in the range of 100-200 IU/ml, and the remaining 5 at low to medium level, 5-50 IU/ml). Thus one case was classified as acute infection (DNA+/IgM-/IgG-) and six as potentially persistent infections (DNA+/IgM-/IgG+). No coinfections with other pathogens of mandatory control in the pre-transfusion screening were detected. Prevalence of IgG was 77.9% (279/358). This study provides the first data of B19V prevalence in blood donors in Argentina, demonstrating high rates of acute and persistent B19V infections and high prevalence of anti-B19V IgG in a post-epidemic period. Further research is needed to elucidate mechanisms/factors for B19V persistence as well as follow-up of recipients in the context of haemo-surveillance programs, contributing to the knowledge of B19V and blood transfusion safety., (© 2020 The Authors. Published by Elsevier Ltd.)

Unlabelled: Human bocavirus (HBoV) is a parvovirus whose association with respiratory disease is currently under investigation., Objective: To determine HBoV prevalence in children with lower acute respiratory infection., Methods: We investigated HBoV in 433 nasopharyngeal aspirates collected in 2007-2009 from children 0 to 5 years old hospitalized with bronchiolitis or pneumonia in Córdoba, Argentina., Results: The general prevalence of HBoV was 21.5% and the positive cases (HBoV+) were more frequent during winter and spring. The mean age of HBoV+ patients was 6.9 months, with 87.1% of the detections corresponding to infants less than 1 year old (among which the prevalence of HBoV was 26.3% in patients < 3 months of age, 22.1% in 3 to 6 months, 25.3% in 6 to 9 months, and 18.8% in 9 to 12 months). The sequence analysis of the NP1 coding region of 15 isolates showed that all isolates from Cordoba were HBoV1 which exhibited a homology of nearly 100% both among themselves and with the originally discovered virus from 2005., Conclusion: Overall, our results indicate that HBoV is a significant pathogen that contributes to acute respiratory infection both on its own and during coinfection with other viruses.

We determined the prevalence of anti-rubella antibodies in 100 serum samples from pregnant women who attended routine examination at a private institution in the city of Córdoba, and in 100 serum samples from women of gestational age, 42 of whom were pregnant, attending health centres in the city of Villa Mercedes, province of San Luis. IgG antibodies against parvovirus 819 were also determined in the serum samples from Córdoba. Using the hemmagglutination inhibition test, we found a 98% prevalence of anti-rubella antibodies among pregnant women in Córdoba and of 96% among the women in Villa Mercedes, whereas the prevalence of anti-parvovirus 819 was 66% in the serum samples from Cordoba. These results coincide with those reported for other cities in the world, and establish an interest in continuing similar studies in order to monitor the immunization plan, which in Argentina has been going on since 1997. They also suggest the importance of the determination of IgM anti-parvovirus B19 in pregnant women who are symptomatic but with a negative result for rubella.

Background: Atherosclerosis is pathogenically similar to a chronic inflammatory response. Peripheral arterial disease (PAD) is a common manifestation of atherosclerosis. Chlamydophila pneumoniae has been suggested to play a role in the origin of PAD., Objective: To determine whether C. pneumoniae is present in atherosclerosis lesions of the carotid artery wall in patients with PAD through several diagnostic methods and to characterize C. pneumoniae susceptibility profiles., Methods: The presence of C. pneumoniae in 9 tissue samples from atherosclerotic lesions obtained by carotid endarterectomy was investigated by 3 methods. Karnofsky-fixed specimens were examined by transmission electron microscopy (TEM), isolation of C. pneumoniae was attempted in LLCMK2 cell structure (ICC), and the presence of chlamydial DNA was investigated by polymerase chain reaction (PCR). The in vitro activities of azithromycin, roxithromycin and penicillin were tested in 4 isolations and the reference strain of C. pneumoniae (AR39)., Results: C. pneumoniae was detected in atherosclerotic plaques from 4 patients with PAD. The pathogen was identified by TEM, PCR and ICC. We report data of the in vitro susceptibility of 4 strains. These strains did not differ from respiratory AR39 strain in their susceptibility patterns to azithromycin, roxithromycin and penicillin., Conclusions: C. pneumoniae is frequently found in the advanced carotid atherosclerotic lesions of patients undergoing endarterectomy. Although these findings do not establish causality in carotid artery atherosclerosis, they should stimulate investigation of the possible causal or pathogenic role of C. pneumoniae. Notably, the profiles of antibiotic susceptibility of C. pneumoniae isolated from 4 of the patients did not differ from those of the reference strain.

Congenital rubella is a persistent infection that contrasts with acute postnatal infection. Basis of the Rubella virus (RV) persistence still remain unknown, though several hypotheses have been postulated. RV induces apoptosis in cell lines, maybe as a way of cell-autonomous defense mechanism against virus. Considering the pattern of c-oncogenes expression during embryogenesis, which promotes proliferation while it inhibits apoptosis in specific cells, at certain times, it can be proposed that when RV infection establishes early in gestation, embryo cells that are proliferating have their apoptotic pathways shut down; then infected proliferating embryo cells cannot execute their apoptotic death program. We here report that RV induces apoptosis in human normal-term placenta chorionic villi explants (CVE) and in monolayers of cytotrophoblasts (CTB), but does not induce apoptosis in primary human embryo fibroblasts (HEF) cultures. These results suggest distinct responses to RV infection when comparing differentiated cells, as CTB, to cells with high proliferating potential, as HEF. RV shoots apoptosis in the former, whereas in fibroblastic dividing cells derived from embryo, RV appears not to be enough stimulus to activate the genetic program of cell death.

In order to facilitate the detection of apoptotic cells (Apo C) in Rubella virus (RV) infected cultures in settings of low resources, we compared hematoxylin and eosin staining (H&E) with the conventional TUNEL technique, and confirmed our findings with DNA electrophoresis and transmission electron microscopy. H&E allowed to distinguish Apo C from non-apoptotic cells. The proportion of Apo C in infected cultures was proportional to the multiplicity of infection (MOI). At a MOI of 10, the percent of Apo C at 3, 4 and 5 days post infection (pi) were 26, 45 and 47%, respectively, which were significantly reduced when the caspase inhibitor z-VAD-fmk was present in the supernatant. By the TUNEL assay, the percent of Apo C in RV-infected cultures were lower (0.8, 1.2 and 1.2% at 3, 4 and 5 days pi, respectively). Our results have shown that H&E staining is an easy, rapid, economic and reproducible method to detect Apo C in RV infected Vero cells cultures. It is possible that H&E makes evident early stages of apoptosis, when an apoptotic cell shows chromatin condensation, nuclear and cytoplasmic contraction (but is still attached to the monolayer), while TUNEL detects later stages of apoptosis because it needs an extensive DNA fragmentation, when apoptotic cells are about to or have already detached from the substratum.

Two monoclonal antibodies (MnAb) directed against the lipopolysaccharide (LPS) and major outer membrane protein (MOMP) of Chlamydia trachomatis were produced for use in indirect immunofluorescence (IFI). The specificity of the antibodies was determined by Dot-blot, Immunoblotting (IB) and IFI onto culture cells infected with C. trachomatis and IFI onto commercial swabs (MRL). The MnAb 2D3 and 3C2 detected LPS and MOMP of C. trachomatis, respectively, by different methods. Neither MnAb showed cross-reactions when other gram-negative bacteria were used as antigens.