Vertical Transmission Of Virus Research Articles

THE LEVEL OF HUMAAN IMMUNODEFICENCY VIRUS VERTICAL TRANSMISSION BY THE RESULTS OF MOLECULAR-GENETICS TESTS

Aim. The aim of the study was the estimation of the frequency of vertical transmission (VT) of human immunodeficiency virus (HIV) in Ukraine (in six regions) using molecular genetic methods of diagnosis. Methods. HIV status of children has been determined by detection of HIV-1 proviral DNA in whole blood samples of children using polymerase chain reaction. The results of the research were analyzed depending on whether HIV-positive pregnant women and children, born by them, have received antiretroviral prophylaxis of HIV VT. Results. On average in three years the frequency of HIV VT among children who received full prophylaxis was 1.15%, partial prophylaxis – 13.12%, among children who did not receive any prophylaxis – more than 25%. Conclusions. According to the results of molecular genetic tests at the present stage of the HIV-infection/AIDS epidemic the rate of HIV VT was 3% in the studied regions. With timely appointment of prophylaxis HIV mother-to-child transmission the rate of HIV vertical transmission in Ukraine can be reduced to less than 2%.

Zika virus infection of Hofbauer cells.

Recent studies have linked antenatal infection with Zika virus (ZIKV) with major adverse fetal and neonatal outcomes, including microcephaly. There is a growing consensus for the existence of a congenital Zika syndrome (CZS). Previous studies have indicated that non-placental macrophages play a key role in the replication of dengue virus (DENV), a closely related flavivirus. As the placenta provides the conduit for vertical transmission of certain viruses, and placental Hofbauer cells (HBCs) are fetal-placental macrophages located adjacent to fetal capillaries, it is not surprising that several recent studies have examined infection of HBCs by ZIKV. In this review, we describe congenital abnormalities associated with ZIKV infection, the role of HBCs in the placental response to infection, and evidence for the susceptibility of HBCs to ZIKV infection. We conclude that HBCs may contribute to the spread of ZIKV in placenta and promote vertical transmission of ZIKV, ultimately compromising fetal and neonatal development and function. Current evidence strongly suggests that further studies are warranted to dissect the specific molecular mechanism through which ZIKV infects HBCs and its potential impact on the development of CZS.

Influence of Hepatitis B immunization to prevent vertical transmission of Hep-B virus in infants bam from Hep-B positive mother

Background Hepatitis B is one of the most common infectious diseases worldv.ide. Indonesia has moderate-high endemicity for hepatitis B infection. Perinatal transmission increases the risk for chronic hepatitis B. Infants from HBsAg-positive mothers should receive hepatitis B immunoglobulin (HBIG) and vaccination within 12 hours of birth, but this practice is not routinely done in Indonesia due to financial constraints.Objectives To detennine the influence of Hep-B immunization on preventing Hepatitis B vertical transmission. Methods A descriptive cohort study was conducted from May 2009 - January 2010. Subjects were term infants born from HBsAg-positive mothers v.ith no history of HBIG administration. They had received complete hepatitis B immunization and 1 month after the last dose were evaluated for HBsAg and anti-HBs. Cord blood was also taken during labor to measure HBsAg.Results There were 22 infants born from HBsAg-positive mother who met the inclusion criteria. HBsAgwas positive in 6 of22 cord blood specimens. There were 15 infants who completed this study. One of 15 infants had positive HBsAg after completed hepatitis B immunization and 12 of 15 infants had protective level of anti-HBs. Effectiveness of hepatitis B immunization to prevent vertical transmission in this study was 70-90%.Conclusion Hepatitis B immunization can prevent vertical transmission of hepatitis B in infants born to mothers who are HBsAg-positive even without administration of HBIG.

Vertical Transmission of Chikungunya virus in Aedes aegypti Mosquitoes from Northern India

Chikungunya virus is now recognised as a resurging arbovirus of global public health significance, with their circulation in both new and old world. It is horizontally transmitted among vertebrates by Aedes mosquitoes. So far, the existence of vertical transmission of Chikungunya virus in Aedes vector is riddled with conflicting reports. In this study, presence of Chikungunya virus was detected in adult Aedes aegypti mosquitoes that emerged from field-collected larvae from Gwalior, northern India during 2010. This was further confirmed through nucleotide sequencing that revealed the presence of novel east central south African (ECSA) genotype of Chikungunya virus. This provides molecular evidence for vertical transmission of Chikungunya virus in mosquitoes in nature, which may have important consequences for viral survival during inter-epidemic period and adverse climatic conditions.

Zika Virus Infection in Early Pregnancy, a Case Report

Objectives: Vertical Zika virus transmission is reported to affect fetal development, and usually the fetal abnormalities can be detected by ultrasonography in second trimester. However, there is no report about the histopathological findings on fetus at earlier stage. Here we present a case of a pregnant woman with Zika virus infection in the first trimester. …

Vertical transmission of Zika virus (ZIKV) in early pregnancy: two cases, two different courses

AbstractBackground:Vertical Zika virus (ZIKV) transmission is actively being studied. Prior cases of ZIKV in pregnancy have suggested an association with infection and adverse fetal outcomes. We describe two cases of maternal illness and their respective pregnancy courses.Case 1: A 30-year-old Hispanic female presented with rash, fatigue, and chills after noticing mosquito bites in Honduras. Fetal anatomy appeared normal on ultrasound at 16 and 17 weeks. ZIKV RNA reverse-transcriptase-polymerase-chain-reaction (RT-PCR) was identified in her serum and amniotic fluid. She opted for pregnancy termination. Fetal serum and tissue analysis confirmed ZIKV infection.Case 2: A 28-year-old Hispanic female presented with rash, fever, and fatigue after sexual intercourse. Her ZIKV serum RNA RT-PCR was positive and amniotic fluid was negative. Fetal anatomy appeared normal at 20 and 22 weeks and her pregnancy remains ongoing.Conclusion:The effects of maternal ZIKV infection in early pregnancy can vary.

Interaction of herpesviruses with mature human spermatozoa in the model system in vitro

The DNA of human herpesviruses (HHV), including the herpes simplex virus (HSV) and cytomegalovirus (CMV), is often identified in ejaculates of patients with urogenital diseases and infertility. At least a part of viral DNA is associated with cell fraction of ejaculate. However, it remains unclear how the semen is infected by the virus. It can be located in gametes or be capable of infecting mature germ cells, including motile sperm cells. In order to resolve this issue, interactions of the CMV and HSV with human sperm cells were studied using an original optimized model of the herpesviral infection of male gametes in vitro. The analysis of the immunofluorescent staining of gametes for viral antigens has shown that CMV infected 2% gametes, while HSV infected 17.26 ± 2.58% gametes. The fraction of progressively motile sperm cells contained 13.99 ± 4.64% infected cells. Localization of HSV was studied by the confocal microscopy. Sometimes, viral gB protein was found on sperm cell membrane. In addition, optical scanning of other cells has shown the intracellular localization of the viral proteins. In the majority of spermatozoa, the viral proteins were observed in the head and neck. In some cells, they were located in the middle piece or, rarely, in the equatorial segment. In general, after in vitro infection HSV antigens were located in the same areas of the sperm cells as in ejaculates from infected patients. According to DNA-DNAhybridization in situ, gametes containingHSV DNAaccounted for 16.94 ± 5.28%, which is consistent with the results obtained in the immunofluorescence assay. It can be concluded that mature male gametes are infected by HHV in the genital tract, where the virus binds to the sperm cell membrane and enters the cell. Interaction of HHV with progressively motile sperm cells implies a vertical viral transmission upon fertilization and points to the necessity of testing ejaculate for herpesviruses infections.

HIV-1 Vertical Transmission in Zimbabwe in 622 Mother and Infant Pairs: Rethinking the Contribution of Mannose Binding Lectin Deficiency in Africa.

Vertical transmission of human immunodeficiency virus (HIV) remains a major global health problem. We assessed the association of mannose binding lectin (MBL) deficiency and vertical transmission of HIV. Novel diagnostics would be a major breakthrough in this regard. MBL is a liver-derived protein and a key component of the innate immune system. MBL levels may be classified as normal, intermediate, or deficient in the plasma and can use MBL2 haplotypes as a proxy. These haplotypes comprise polymorphisms in the MBL2 gene and promoter region and are known to result in varying levels of MBL deficiency. MBL deficiency can be defined as presence of A/O and O/O genotypes in the mothers and their children. MBL deficiency leads to defective opsonization activities of the innate immune system and increased susceptibility to several infections, including HIV-1. We determined the prevalence of MBL deficiency, using MBL2 haplotypes among 622 HIV-positive Zimbabwean mothers and their children aged 9-18 months old, in relation to the HIV-1 vertical transmission risk. The median age of the mothers was 30 (26-34, interquartile range [IQR]) years, and the babies' median age was 13 (11-15, IQR) months old at the time of enrollment. From the sample of 622 mothers who were HIV-1 infected, 574 babies were HIV negative and 48 were HIV-1-positive babies, giving a transmission rate of 7.7%. MBL2 normal structural allele A and variants B (codon 5 A>G), C (codon 57 A>G), and promoter region SNPs -550(H/L) and -221(X/Y) were detected. Prevalence of haplotype-predicted MBL deficiency was 34% among the mothers and 32% among the children. We found no association between maternal MBL2 deficiency and HIV-1 transmission to their children. We found no difference in the distribution of HIV-1 infected and uninfected children between the MBL2 genotypes of the mothers and those of the children. Taken together, the present study in a large sample of mother-infant pairs in Zimbabwe adds to the emerging literature and the hypothesis that MBL2 variation as predicted by haplotypes does not influence the vertical transmission risk for HIV. Research from other populations from the African continent is called for to test this hypothesis further.

Evidence for natural vertical transmission of chikungunya viruses in field populations of Aedes aegypti in Delhi and Haryana states in India—a preliminary report

Aedes aegypti and Aedes albopictus are principal vectors for the transmission of chikungunya virus (CHIKV). India is a hub for both dengue and chikungunya infections and there are several reports of co-infection of dengue and chikungunya virus in the clinical scenario. The present pilot entomological survey was conducted to evaluate vertical transmission of CHIKV in Aedes field populations. Aedes immature (larvae and pupae) collection was done in 2012, over a period of six months from selected sites in Delhi and Haryana, India. The immatures collected were reared for adult emergence and species identification was done. A. aegypti male and female mosquitoes were separated and pooled collection spot-wise, RNA extracted and RT PCR performed to test for the presence of CHIKV in the pools. Container index (CI) and minimum infection rate (MIR) were estimated. From study areas that tested positive for CHIKV, adult collections were made and females upon feeding on uninfected blood in laboratory were allowed to lay eggs. The progeny that emerged from these field-collected mothers were tested for CHIKV presence. Our pilot survey showed the existence of A. aegypti population even during peak summer season in a few foci which eventually helped the mosquitoes to tide over adverse environmental conditions and with the start of rainfall, the population exploded within a short period of time. Immatures collected from field and progeny of adults collected from the field were CHIKV positive demonstrating the presence of vertical transmission of chikungunya virus in field population of A. aegypti. The present study further demonstrates the importance of identifying permanent breeding sites for proper Aedes species control.

Evidence of DENV-2 Vertical Transmission in LarvalAedes aegyptiPopulations at Cancun, Quintana Roo, Mexico

Abstract. Evidence of vertical transmission of dengue virus (DENV) in yellow fever mosquito, Aedes aegypti (L.), was found at Cancun, Quintana Roo, Mexico. Ae. aegypti larvae were collected from 729 containers in a total of 178 households between September and November 2012. Larvae collected were put into sterile bags and transported in thermoses. RT-PCR followed by semi-nested PCR for molecular serotyping was used to evaluate for dengue virus in larval pools. Of the 178 houses sampled, 79 (44.4%) were positive for at last one Ae. aegypti larva. The positive breeding sites were grouped into a total of 79 pools. Only three larval pools from three houses close together were positive for DENV-2. The infection rate was 0.32 per 1,000 mosquitos (95% CI 0.09–0.85 per 1,000 mosquitoes). The result of this report suggested that vertical transmission of dengue virus in Ae. aegypti might be a mechanism of viral perpetuation during inter-epidemic periods.

Zika virus: what do we know about the viral structure, mechanisms of transmission, and neurological outcomes?

The Zika virus epidemic that started in Brazil in 2014 has spread to >30 countries and territories in Latin America, leading to a rapid rise in the incidence of microcephalic newborns and adults with neurological complications. At the beginning of the outbreak, little was known about Zika virus morphology, genome structure, modes of transmission, and its potential to cause neurological malformations and disorders. With the advancement of basic science, discoveries of the mechanisms of strain variability, viral transfer to the fetus, and neurovirulence were published. These will certainly lead to the development of strategies to block vertical viral transmission, neuronal invasion, and pathogenesis in the near future. This paper reviews the current literature on Zika virus infections, with the aim of gaining a holistic insight into their etiology and pathogenesis. We discuss Zika virus history and epidemiology in Brazil, viral structure and taxonomy, old and newly identified transmission modes, and neurological consequences of infection.

Vertical transmission of Zika virus targeting the radial glial cells affects cortex development of offspring mice.

The recent Zika virus (ZIKV) epidemic in Latin America coincided with a marked increase in microcephaly in newborns. However, the causal link between maternal ZIKV infection and malformation of the fetal brain has not been firmly established. Here we show a vertical transmission of ZIKV in mice and a marked effect on fetal brain development. We found that intraperitoneal (i.p.) injection of a contemporary ZIKV strain in pregnant mice led to the infection of radial glia cells (RGs) of dorsal ventricular zone of the fetuses, the primary neural progenitors responsible for cortex development, and caused a marked reduction of these cortex founder cells in the fetuses. Interestingly, the infected fetal mice exhibited a reduced cavity of lateral ventricles and a discernable decrease in surface areas of the cortex. This study thus supports the conclusion that vertically transmitted ZIKV affects fetal brain development and provides a valuable animal model for the evaluation of potential therapeutic or preventative strategies.

Vertical transmission of Infectious myonecrosis virus in Litopenaeus vannamei

In the farmed whiteleg shrimp (Litopenaeus vannamei), Infectious myonecrosis virus (IMNV) accounts for 70% of the cumulative mortality during the growout cycle. Although the horizontal transmission of IMNV has been demonstrated, vertical transmission remains unknown, which may be a crucial factor to the prevention of IMNV from one generation to the next. Thus, the aim of the present study was to determine the possibility of the vertical transmission of IMNV by experimental infection in SPF and non-SPF L. vannamei broodstocks using an intramuscular procedure. Evaluations involved the use of molecular methods (Real-time PCR and conventional PCR) for spermatophores, ovaries and eggs tissues. The effect of IMNV infection on sperm viability was also evaluated. Conventional PCR detected IMNV in spermatophores, mature ovaries and muscle tissue from experimentally infected specific pathogen-free (SPF) broodstock. Real-time PCR confirmed IMNV replication in all samples (spermatophores, mature ovaries, muscle tissue and eggs — fertilized or not) from naturally and experimentally infected non-SPF broodstock. No significant difference in viral load of the reproductive organs/tissues was found between naturally or experimentally infected shrimp (both sexes) (p≥0.05). However, a significant difference was found regarding mean viral load in the muscle tissue of all shrimps (males and females) in comparison to other tissues, with dissimilar viral load values for naturally and experimentally infected muscle tissue for both sexes (p≤0.05). With regard to spawning, all infected females spawned and no significant difference was found in the viral load of eggs produced by naturally and experimentally infected females. The eggs were classified as two morphological types (type B and A2) based on morphology and post-spawning development. Sperm viability of experimentally infected males was not determined due to the low cell density, whereas mean viability among naturally infected males was 82%. In the control group, mean sperm viability was 91%. The results suggest that IMNV can be transmitted vertically in L. vannamei. However, nauplii did not hatch out, which prevented a better understanding of the mechanisms by which eggs become infected following spawning (egg surface or by transovarial transmission). Nonetheless, the 100% positive samples from ovaries and eggs and the low percentage of viable cells from naturally infected males suggest that females are the primary source of the vertical transmission of IMNV to eggs. Statement of relevanceThis study reports the first scientific evidence of IMNV vertical transmission in L. vannamei. The study suggests the use of IMNV-free broodstock as an effective prevention measure in order to minimize propagation in L. vannamei farming operations.

Twenty Years of Improved Perinatal Outcomes for Pregnancies Affected by HIV Infection

Background: Highly active antiretroviral therapy has emerged as an essential treatment component to prevent vertical transmission of Human Immunodeficiency Virus (HIV). Yet there often remain missed opportunities to prevent vertical HIV transmission. We present a case that illustrates obstetric management and outcome for involving 2 generations of congenital HIV transmission. Presentation of the Case: Patient is a 19-year-old primigravida with congenital HIV presented to Lincoln Medical and Mental Health Center’s for her initial prenatal care at 36 weeks of gestation. Upon documentation of a high viral load, the patient was given intravenous Azidothymidine and scheduled for Caesarean delivery. AZT and lamivudine were recommended and prescribed for the neonate who tested positive HIV test for which AZT and lamivudine were recommended and prescribed, but the mother discontinued AZT after discharge from the hospital. At 1 month of age the infant succumbed to sudden infant death syndrome (SIDS). During the 2nd pregnancy the patient received adequate prenatal care as well as antiretroviral therapy, Truvada, Abacavir, Mepron, and Kaletra throughout the antenatal course. After preoperative intravenous AZT, via a repeat cesarean the patient delivered a neonate whose HIV test was negative. The patient’s 2nd child had an uncomplicated neonatal course and was negative for HIV on 3 subsequent tests and remained HIV negative until this date. Antiretroviral were removed and the child has remained HIV negative. The mother died from pneumonia and respiratory failure secondary to HIV 2 years after the 2nd delivery. Conclusion: This case serves as a reminder of the importance of adhering to current clinical standards for the care of pregnancies affected by HIV infection.

Costs and benefits of vertical and horizontal transmission of dengue virus.

Parasites can be transmitted vertically and/or horizontally, but the costs or benefits for the host of infection have only been tested after horizontal transmission. Here, we report for the first time, to our knowledge, the survival, reproduction and infection of Aedes aegypti during vertical and horizontal transmission of dengue virus 2 (DENV-2). Females infected horizontally produced more eggs, with a sex ratio skewed towards males, compared with uninfected controls. However, there was no significant difference in the number of emerging adults or in survival of mothers. In contrast, dengue-infected female offspring (vertical transmission) had a shorter lifespan but there were no significant differences in the number of eggs or sex ratio, compared with controls. Finally, the corroboration of infection revealed that virus infected about 11.5% and 8.8% of pools of mothers and of daughters, respectively. These results suggest that the mode of infection and the contact with the virus has no reproductive costs to female mosquitoes, which may explain why both types of transmission are evolutionarily maintained. In addition, we suggest that more attention should be paid to the male contribution to virus dissemination within and among populations and as reservoirs of the infection for human diseases.

Study of main grapevine viruses transmission in breeding programs

A number of studies have established that vertical transmission of viruses is an important phenomenon affecting a wide range of viruses, especially as a result of breeding programs. Nevertheless, the presence of virus in a seed, does not always lead to seedling infection. In grapevine, seed transmission has been reported for many nepoviruses, but little is known about the other virus associated diseases such as Leafroll, Rugose wood complex and Fleck diseases, that are considered by Italian legislation on certification of grapevine propagation material, together with infectious degeneration. Thus, the aim of this study is monitoring the virological condition of seedlings obtained by crosses between infected parentals, analyzing the sanitary status of seedlings after the transfer in experimental fields. In this study, 50 progeny plants from three different traditionally crossbreed seeded and seedless table grape cultivars were investigated for the detection of nine grapevine viruses. It was observed that the viral state of parentals was quite compromised, while viruses were not detected in any of the 150 progeny plants, demonstrating that the main grapevine viruses are at low risk for seed transmission. These results could make it possible to reduce the precautions to obtain propagation material free from infectious diseases and also suggest to consider reproduction as a new procedure of sanitation in breeding programs.

Evidence of vertical transmission and co-circulation of chikungunya and dengue viruses in field populations ofAedes aegypti(L.) from Guerrero, Mexico: Table 1.

We report results of the entomo-virological surveillance system in Aedes aegypti local populations performed by the Ministry of Health of Guerrero. Indoor-adult Ae. aegypti collected at Acapulco, Zihuatanejo, Coyuca de Benitez and Atoyac de Alvarez (dry season, 2015) were processed for dengue virus (DENV) and chikungunya virus (CHIKV) using RT-PCR. We identified different seroptypes of DENV (2, 3 and 4), CHIKV and their co-circulation in field-caught mosquitoes across a significant geographic area. Pools of males were positive for CHIKV and DENV 3 and 4 suggesting vertical transmission. Entomo-virological surveillance in Guerrero has identified early circulation of CHIKV and DENV and provided a trigger for timely and focalized vector control actions.

Complete Genome Sequence of the Porcine Epidemic Diarrhea Virus Variant CH/HNYF/2014.

Sow’s milk is a potential route for the vertical transmission of porcine epidemic diarrhea virus (PEDV) from sow to suckling piglet. We report here the complete genome sequence of PEDV strain CH/HNYF/2014, which was isolated from milk samples. This information provides further understanding of the transmission mechanisms and genetic diversity of PEDV.

Prevalence of human papillomavirus and herpes simplex virus in amniotic fluid from pregnant women of Eastern Poland.

The exact route of human papillomavirus (HPV) and herpes simplex virus (HSV) transmission from a pregnant woman to her fetus has not been clearly established thus far. The data of many studies raise the possibility of intrauterine infection. In order to clarify our knowledge about virus vertical transmission in pregnant women, viral prevalence in amniotic fluid cannot. To the best of our knowledge, this is the first study on HPV DNA and HSV DNA detection in amniotic fluid in Poland. The study covered 138 samples of amniotic fluid from patients undergoing invasive prenatal diagnostic procedures (for medical indications) during the second trimester of gestation. The aim of the study was to assess the prevalence of HPV and HSV in the amniotic fluid samples obtained from asymptomatic women with intact amniotic membranes. To identify viral DNA of HPV and HSV in collected material, polymerase chain reaction (PCR) was performed. We did not find HPV or HSV DNA in any of the examined specimens of amniotic fluid. Our investigation did not confirm the prenatal transmission of HPV and HSV to the amniotic fluid.

Natural vertical transmission of dengue viruses in Aedes aegypti in selected sites in Cebu City, Philippines.

We attempted to determine the vertical transmission of dengue virus (DENV) in Aedes aegypti in selected sites in Cebu City, Philippines. Mosquito sub-adults were collected monthly from households and the field during the wet-dry-wet season from November, 2011 to July, 2012 and were laboratory-reared to adults. Viral RNA extracts in mosquitoes were assayed by hemi-nested RT-PCR. Results showed that 62 (36.26%; n=679) out of 171 mosquito pools (n=2,871) were DENV+. The minimum infection rate (MIR) of DENV ranged from 0 in wet months to 48.22/1,000 mosquitoes in April, 2012 (mid-dry). DENVs were detected in larvae, pupae, and male and female adults, with DENV-4, DENV-3, and DENV-1, in that rank of prevalence. DENV-1 co-infected with either DENV-3 or -4 or with both in April, 2012; DENV-3 and -4 were present in both seasons. More DENV+ mosquitoes were collected from households than in field premises (p<0.001) and in the dry than in the wet season (p<0.05), with significant interaction (p<0.05) between sites and premises but no interaction between sites and seasons (p>0.05). By Generalized Linear Mixed models, the type of premises nested in sites and monthly total rainfall were significant predictors of monthly dengue cases (p<0.05) and not MIR, season, temperature, and relative humidity. Surveillance of DENV prevalence in Ae. aegypti and detecting their natural foci in the dry season provide an early warning signal of dengue outbreak.