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BACKGROUND: Pregnant women are vulnerable against COVID-19 infection due to physiological and immunological changes. COVID-19 in pregnancy affects fetal well-being with a potential for vertical infection. AIM: This study aims to determine the incidence of vertical infection and anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in infants born to mothers with positive COVID-19 infection. MATERIALS AND METHODS: Amniotic fluid, swabs of the newborn's nasopharynx and oropharynx, and swabs of the placenta were examined using reverse transcription polymerase chain reaction (RT-PCR) for SARS-CoV-2. Serological examination was performed by Electro-Chemiluminescence Immunoassay on infant's blood. RESULT(S): Four of 33 pregnant women gave birth to infants positive SARS-CoV-2 infection. RT-PCR examination of all amniotic fluid and placental swabs was negative for SARS-CoV-2. Four of 33 infants (12.1%) showed negative polymerase chain reaction (PCR) results but positive SARS-CoV-2 antibodies, another 4 newborns (12.1%) showed positive PCR results, but no SARS-CoV-2 antibodies detected. The remaining 25 babies (75.8%) showed both negative PCR and serologic results. CONCLUSION(S): No evidence of vertical transmission found in this study.Copyright © 2023 Cut Meurah Yeni, Zinatul Hayati, Sarjani M. Ali, Hasanuddin Hasanuddin, Rusnaidi Rusnaidi, Cut Rika Maharani.
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Ever since the beginning of COVID-19 pandemic, uncertainty regarding clinical presentation and differences among various subpopulations exist. With more than 209,870,000 confirmed cases and more than 4,400,000 deaths worldwide, we are facing the new era of health crisis which will undoubtedly impair global health, economic and social circumstances. In the past year, numerous genetic mutations which code SARS-CoV-2 proteins led to the occurrence of new viral strains, with higher transmission rates. Apart from the implementation of vaccination, the effect of SARS-CoV-2 on pregnancy outcome and maternal fetal transmission remains an important concern. Although neonates diagnosed with COVID-19 were mostly asymptomatic or presented with mild disease, the effect on early pregnancy is yet to be evident. While positive finding of SARS-CoV-2 RNA in some samples such as amniotic fluid, placental tissue, cord blood and breast milk exists, additional research should confirm its association with transplacental transmission.Copyright © 2022, Dr. Mladen Stojanovic University Hospital. All rights reserved.
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Cumulative data regardingCOVID-19 infection during pregnancy have demonstrated the ability of SARS-CoV-2 to infect the placenta. However, the mechanisms of SARS-CoV-2 placental viral entry are yet to be defined. SARS-CoV-2 infects cells by binding to the ACE2 receptor. However, SARS-CoV-2 cell entry also requires co-localization of spike protein cleavage by the serine protease TMPRSS2. However, the co-expression of ACE2 and TMPRSS2 in placental cells is debated, raising the question of whether potential non-canonical molecular mechanismsmay be involved in SARS-CoV-2 placental cells' viral entry. Although published data regarding the ability of the SARS-CoV- 2 to infect the fetus are contradicting, the placenta appears to be an immunological barrier to active SARS-CoV-2 infection and vertical transmission;however, the mechanism is unclear. Our experiments demonstrated the ability of the SARS-CoV-2 virus to directly infect the placenta and induce transcriptomic responses in COVID-positive mothers. These transcriptomic responses were characterized by differential expression of specific mRNAs and miRNAs associated with SARS-CoV-2 infection, with induction of specific placental miRNAs that can inhibit viral replication. Failure in such mechanisms may be associated with vertical transmission. Since the start of the COVID-19 pandemic, the COVID-19 mRNA vaccines have been widely used to reduce the morbidity and mortality of SARS-CoV-2 infection. Historically, non-live vaccines have not caused any harm to pregnant mothers;however, it is unclear whether our current understanding of the effects of non-live vaccines serves as a reliable precedent owing to the novel technology used to create these mRNA vaccines. Since there are no definitive data on the possible biodistribution of mRNA vaccines to the placenta, the likelihood of vaccine mRNA reaching the fetus remains uncertain. Little has been reported on the tissue localization of the lipid nanoparticles (LNPs) after intramuscular (IM) administration of the mRNA vaccine. The biodistribution of LNPs containing the mRNA vaccine has been investigated in animal models but not humans. In the murine model, the vaccine LNPs were rapidly disseminated to several organs, including the heart, liver, kidney, lung, and spleen, following IM administration. However, no traditional pharmacokinetic or biodistribution studies have been performed with the mRNA vaccines, including possible biodistribution to breast milk or the placenta.
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SARS-CoV-2 infection in pregnancy is associated with increased risk for severe COVID-19 disease including ICU admission, need for invasive ventilation, extracorporeal membrane oxygenation, and death. In addition, COVID-19 in pregnancy is associated with adverse pregnancy and neonatal outcomes. This presentation will review: (1) what is known about increased maternal and obstetric risk in the setting of SARS-CoV-2 infection;(2) how underlying comorbidities and viral strain may impact disease severity;(3) impact of COVID-19 in pregnancy on the placenta and how this may be altered by fetal sex and viral strain;(4) fetal risk and protection including vertical transmission, antibody-mediated protection, and later-life neurodevelopmental or metabolic risk in the setting of maternal immune activation.
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Purpose - to draw attention to an infection that was little known, but has now become a global problem for society;to familiarize readers with the peculiarities of the 2022 monkeypox outbreak and to increase the level of alertness of doctors to this disease. Monkeypox is a global problem because the disease is spreading rapidly, covering 111 countries. Three cases were diagnosed in Ukraine. It is predominantly a self-limited infection, but there are severe and deadly complications. The lethality of this disease ranges from 0% to 11%. The course of the disease is more severe in children and people with reduced immunity. Vertical transmission of the virus from mother to child is possible, resulting in congenital monkeypox. Monkeypox is a zoonotic disease and its natural reservoir is not exactly known, but rodents are most likely to act. In most cases, person-to-person transmission of the virus occurs through close skin to skin contact, often during sexual intercourse. At the beginning of the outbreak 98% of cases of disease were was diagnosed in homo- and bisexuals. Airborne transmission is also possible. Infection is possible through close contact with infectious skin lesions. Clinically, the initial period resembles influenza, but lymphadenopathy is characteristic, which is considered a pathognomonic symptom of mpox. The rash is similar to that of chickenpox, but with more prevalent location on palms and soles than in chickenpox. In the presence of a vesicular rash in a patient, it is necessary to exclude monkeypox. PCR diagnostics of the virus in samples of vesicles or crusts has the greatest diagnostic value. Hygienic skin care is important. Antiviral drugs (tecovirimat, brincidofovir) are recommended only in severe cases. To reduce the spread of infection, international rules apply as for other infections, such as COVID-19. The monkeypox virus vaccine is recommended primarily for groups at risk of infection, including medical personnel who may come into contact with the patient or samples for laboratory testing. Being aware for this infection, following international health regulations, it is possible to prevent the further spread of monkeypox.Copyright © 2023 Tomsk State University. All rights reserved.
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Background: Pregnant women with the novel coronavirus disease (COVID-19) are more likely than non-pregnant women to develop severe COVID-19 complications. In addition, COVID-19 is linked to unfavorable pregnancy outcomes. Due to the lack of effective COVID-19 treatment, it is critical to assess geographic differences and trends in current clinical care and the effect of COVID-19 on pregnant women. This review aims to evaluate maternal and neonatal outcomes in COVID-19 pregnancies. We searched the Medline database for research papers from January 2019 to December 31, 2021. Eleven studies of systematic, meta-analysis, review, and cohort designs were included with searched keywords {Pregnancy AND COVID [MeSH Terms]}. This study summarizes the maternal characteristics, vertical Transmission, maternal and neonatal outcomes, the rate of cesarean section, comorbidities, mechanical ventilation, ICU admission rate, mode of delivery, type of anesthesia, the average hospital length of stay (HLOS), the extracorporeal membrane oxygenation (ECMO), preeclampsia, pregnancy-induced hypertension, chest x-ray and CT scan findings, treatments, and outcomes over time. © 2020 The author (s).
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In spite of various reports on perinatal outcomes of coronavirus disease 2019 (COVID-19) during pregnancies, the effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on unborn babies and pregnant mothers are still mysterious. The goal of our research is to examine the perceived fetomaternal outcomes of COVID-19 during pregnancy. A total of 396 pregnant women were admitted to the Department of Gynaecology and Obstetrics, Pt. JNM Medical College, Raipur, Chhattisgarh, India, during the period from July 20, 2020 to January 6, 2021. The presence of SARS-CoV-2 in different biological samples was recorded via positive quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) test results. All the newborns delivered from the infected pregnant mothers were tested as RT-PCR negative. Negative findings of RT-PCR for respiratory swabs of newborns, amniotic fluid, placental tissue, breast milk, vaginal swabs, and cord blood indicated no transmission of the virus from mother to baby. However, maternal outcomes, such as hospitalization (46.96%), preeclampsia (13.88%), pre-term birth (14.39%), prelabor rupture of membranes (PROM) before 34 weeks (3.78%), PROM before 37 weeks (2.77%), vaginal bleeding (4.29%), postpartum hemorrhage (2.52%), pregnancy-induced hypertension (1.51%), and neonatal outcomes such as low birth weight ≤1.5 kg (6.59) and 1.6-2.4 kg (39.34%), intrauterine deaths (IUD) (0.50%), fetal distress (22.33%), NICU admission (5.58%), meconium-stained liquor (14.46%), diarrhea (0.25%), and low APGAR score 4-6 at 1 min (20.54%), were observed. The results of the present study indicate that SARS-CoV-2-induced complications during pregnancy must be taken seriously. Intrauterine fetal deaths occurred at lower rates. There is no substantial proof of vertical perinatal transmission of the virus, as none of the neonates had tested positive for COVID-19.
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SARS-CoV-2, a member of the family Coronaviridae, is a positive-stranded RNA virus with the spike glycoproteins present on its envelope. ACE2 serves as the entry mediator of SARS-CoV-2 as it attacks mainly the organs of the respiratory, cardiovascular, digestive, and urinary system showing high expression of ACE2 or TMPRSS2. ACE2 is found to have significant differential expression in all the reproductive tissues, thus posing the reproductive system vulnerable to the adverse effects of SARS-CoV-2 infection. Previous coronavirus attacks (SARSCoV and MERS) have also been known to impose adverse effects on the reproductive system. Therefore, there is a dire need to safeguard the reproductive system against COVID-19 as it not only bothers the present generation but may also affect the well-being of future progeny. Since the inception of pandemic, several scientific studies have been carried out to assess its impact;yet there are research lacunas to claim reproductive system as a potential target of this deadly virus. To avoid the detrimental effects of the current pandemic on reproductive sustainability, well-planned large-scale and multicentric cohort follow-up studies are mandatory for accurate evaluation of the enduring effects of SARS-CoV-2 infection on human fertility and pregnancy outcomes. © The Author(s), under exclusive licence to Springer Nature Singapore Pte Ltd. 2021.
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Pregnancy is a physiological state that predisposes women to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, a disease that can cause adverse maternal and perinatal outcomes. The severity of coronavirus disease 2019 (COVID-19) disease is known to vary by viral strain;however, evidence for the effects of this virus in pregnant women has yet to be fully elucidated. In this review, we describe maternal and perinatal outcomes, vaccination, and vertical transmission, among pregnant women infected with the different SARS-CoV-2 variants identified to date. We also summarize existing evidence for maternal and perinatal outcomes in pregnant women with specific information relating to SARS-CoV-2 variants. Our analysis showed that Omicron infection was associated with fewer severe maternal and perinatal adverse outcomes while the Delta variant was associated with worse pregnancy outcomes. Maternal deaths arising from COVID-19 were found to be rare (<1.0%), irrespective of whether the virus was a wild-Type strain or a variant. Severe maternal morbidity was more frequent for the Delta variant (10.3%), followed by the Alpha (4.7%), wild-Type (4.5%), and Omicron (2.9%) variants. The rates of stillbirth were 0.8%, 4.1%, 3.1%, and 2.3%, respectively, in pregnancies infected with the wild-Type strain, Alpha, Delta, and Omicron variants, respectively. Preterm birth and admission to neonatal intensive care units were more common for cases with the Delta infection (19.0% and 18.62%, respectively), while risks were similar for those infected with the wild-Type (14.7% and 11.2%, respectively), Alpha (14.9% and 13.1%), and Omicron variants (13.2% and 13.8%, respectively). As COVID-19 remains a global pandemic, and new SARS-CoV-2 variants continue to emerge, research relating to the specific impact of new variants on pregnant women needs to be expanded.Copyright © Wolters Kluwer Health, Inc. All rights reserved.
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Background: Following the pandemic caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), and considering its capacity for rapid mutation, there have been many studies and articles on this novel coronavirus over the past three years. Therefore, providing knowledge and directions for management of SARS-CoV-2, for hospital staff is crucial. Hence, we collected the research information from different perspectives and summarized the guidelines for perinatal care on the topic of SARS-CoV-2, and for possible future viral pandemics. Method(s): A systematic review aimed at assessing the publications written in English and Chinese, offering different perspectives on the topic of perinatal care concerning SARS-CoV-2, was conducted using PubMed and Google Scholar from 2020 to 2022. In addition, we summarized the guidelines from the Taiwan Association of Obstetrics and Gynecology, American College of Obstetricians and Gynecologists, Society for Maternal-Fetal Medicine, Maternal Immunization Task Force and Partners, and Academy of Breastfeeding Medicine. Result(s): Due to physiological changes, pregnant patients may be prone to have complications, especially pre-eclampsia, affecting morbidity and mortality. Most neonates of coronavirus disease (COVID-19) infected mothers did not show any clinical abnormalities due to the infection. However, compared to the general population, infected neonates needed more invasive ventilation care, while the proportion of asymptomatic neonates was less than that in the general population. Further, long term complications are still under investigation. Evidence of vertical transmission via the placenta and umbilical cord is rare but not absent. Paxlovid (nirmatrelvir/ritonavir) can be administered to patients with comorbidities, and indications for cesarean delivery does not include COVID-19 infection. Vaccination against COVID-19 should not be delayed during pregnancy and lactation. Conclusion(s): Obstetricians and gynecologists should pay more attention to pregnant women with SARS-CoV-2 because of the physiological changes and higher risks of complications, morbidity, and mortality. Early prevention with vaccination in pregnant women is the key to controlling the COVID-19 pandemic, from which we can learn how to manage the next pandemic.Copyright © 2023 The Author(s).
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Background: In new pandemic, the probable effects of COVID-19 pneumonia on pregnant woman and their infant is one of new critical challenge for health care. Here we presented clinical symptoms, laboratory findings and outcome of COVID-19 pneumonia in pregnant woman. Method(s): In a case series study, from 15 Feb to 15 June 2020, all women with RT-PCR COVID-19 who referred to two hospitals (Taleghani and Qods Hospital) affiliated to Arak University of Medical Sciences were selected. The epidemiological and demographic variables, laboratory test and outcomes obtained from patient's medical records. Result(s): In this case series, we presented thirteen confirmed COVID-19 pregnant women. Their mean age was 34.6 (S.D.: 5.9) years and the mean gestational age was 32.4 (S.D.: 7.3) weeks. Most of patient didn't show any maternal complication and intrauterine vertical transmission. The large number of pregnant women had normal HRCT and also in terms of laboratory most of the patients had normal laboratory tests. Amniotic fluids, cord blood, the throat swab of neonate in our pregnant woman with delivery were tested for COVID-19 and all of them were negative. Conclusion(s): The COVID-19 mothers and their infant didn't have higher risk for morbidity and mortality and this virus didn't associate with intrauterine vertical transmission.Copyright © 2020 Ubiquity Press. All rights reserved.
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As the COVID-19 pandemic continues into its third year, there is accumulating evidence on the consequences of maternal infection. Emerging data indicate increased obstetrics risks, including maternal complications, preterm births, impaired intrauterine fetal growth, hypertensive disorders, stillbirth, gestational diabetes, and a risk of developmental defects in neonates. Overall, controversial concerns still exist regarding the potential for vertical transmission. Histopathological examination of the placenta can represent a useful instrument for investigation and can contribute significant information regarding the possible immunohistopathological mechanisms involved in developing unfavorable perinatal outcomes. Based on current evidence, SARS-CoV-2 infection can affect placental tissue by inducing several specific changes. The level of placental involvement is considered one of the determining factors for unfavorable outcomes during pregnancy due to inflammation and vascular injuries contributing to complex cascade immunological and biological events; however, available evidence does not indicate a strong and absolute correlation between maternal infection, placental lesions, and obstetric outcomes. As existing studies are still limited, we further explore the placenta at three different levels, using histology, immunohistochemistry, and molecular genetics to understand the epidemiological and virological changes observed in the ongoing pandemic.
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BACKGROUND: Several viral infections cause changes in the placenta. Cytomegalovirus, herpes viruses, and HIV cause increased placental thickness; Zika virus induces focal regions of necrosis; parvovirus B19 causes a structural injury. Umbilical flow can be considered a direct measurement of vascular placental function. OBJECTIVE: This study aimed to compare placental ultrasound and umbilical Doppler findings in pregnant women who tested positive or negative for SARS-CoV-2. Our work aimed to confirm the suspicion of placental infection and the consequence in fetal physiopathology. STUDY DESIGN: Fifty-seven pregnant women who tested positive for SARS-CoV-2 at the time of or 1 month before the ultrasound scan were evaluated. Cases included 9 first trimester, 16 second trimester, and 32 third trimester ultrasound scans. For comparison, 110 pregnant women (controls) were evaluated. They included 19 women in their first trimester, 43 in their second trimester, and 48 in the third trimester. Controls were asymptomatic and tested negative for SARS-CoV-2 infection in the last 72 hours before the ultrasound scan. Fetal biometry, placental thickness, placental lakes and Doppler umbilical vein parameters, including venous cross-sectional area (mean transverse diameter and radius of umbilical vein, mean velocity of umbilical vein), and umbilical vein blood flow were evaluated. RESULTS: Placental thickness (in millimeter) was significantly higher in the group of pregnant women with SARS-CoV-2 infection (53.82 [10-115]) than in the control group (33.82 [12-66]; P<.001) in their second and third trimesters. The frequency of >4 placental lakes was significantly higher in the group of pregnant women with SARS-CoV-2 infection (28/57 [50.91%]) than in the control (7/110 [6.36]; P<.001) in all 3 trimesters. The mean velocity of umbilical vein was significantly higher in the group of pregnant women with SARS-CoV-2 infection (12.45 [5.73-21]) than in the control group (10.81 [6.31-18.80]; P=.001) in all 3 trimesters. Umbilical vein blood flow (in milliliter per minute) was significantly higher in the group of pregnant women with SARS-CoV-2 infection (389.9 [6.52-1496.1]) than in the control group (305.05 [3.11-1441]; P=.05) in all 3 trimesters. CONCLUSION: Significant differences in placental and venous Doppler ultrasound were documented. Placental thickness, placental venous lakes, mean velocity of umbilical vein, and umbilical vein flow were significantly higher in the group of pregnant women with SARS-CoV-2 infection in all 3 trimesters.
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OBJECTIVE: To assess the impact of maternal Coronavirus disease 2019 (COVID-19) infection on placental histopathological findings in an unselected population and evaluate the potential effect on the fetus, including the possibility of vertical transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). DESIGN: Retrospective cohort comparative study of placental histopathological findings in patients with COVID-19, compared with controls. SETTING: During the COVID-19 pandemic, placentas were studied from women at University College Hospital London who reported and/or tested positive for COVID-19. POPULATION: Of 10 508 deliveries, 369 (3.5%) women had COVID-19 during pregnancy, with placental histopathology available for 244 women. METHODS: Retrospective review of maternal and neonatal characteristics, where placental analysis had been performed. This was compared with available, previously published, histopathological findings from placentas of unselected women. MAIN OUTCOME MEASURES: Frequency of placental histopathological findings and relevant clinical outcomes. RESULTS: Histological abnormalities were reported in 117 of 244 (47.95%) cases, with the most common diagnosis being ascending maternal genital tract infection. There was no statistically significant difference in the frequency of most abnormalities compared with controls. There were four cases of COVID-19 placentitis (1.52%, 95% CI 0.04%-3.00%) and one possible congenital infection, with placental findings of acute maternal genital tract infection. The rate of fetal vascular malperfusion (FVM), at 4.5%, was higher compared with controls (p = 0.00044). CONCLUSIONS: In most cases, placentas from pregnant women infected with SARS-CoV-2 virus do not show a significantly increased frequency of pathology. Evidence for transplacental transmission of SARS-CoV-2 is lacking from this cohort. There is a need for further study into the association between FVM, infection and diabetes.
Subject(s)
COVID-19 , Pregnancy Complications, Infectious , Reproductive Tract Infections , Female , Humans , Pregnancy , COVID-19/epidemiology , Infectious Disease Transmission, Vertical , Pandemics , Placenta/blood supply , Pregnancy Complications, Infectious/epidemiology , Retrospective Studies , SARS-CoV-2ABSTRACT
Introduction: Human species is confronting with a gigantic global COVID-19 pandemic. Initially, it was observed in Wuhan, China, and the COVID-19 cases spread across the globe with lightning speed and resulted in the 21st century pandemic. If scientific reports are taken care of, it is noteworthy that this virus possesses more specific characteristics due to its structure. The distinctive structure has a higher binding affinity with angiotensin-converting enzyme 2 (ACE2) protein, and this is used as an access point to gain access to hosts. Methods: A complete literature search was conducted using PubMed, Google Scholar, SciFinder, and deep-diving Google Search using keywords such as "Pregnancy, COVID-19, Newborn, Fetus, Coronavirus 2019, Neonate, Pregnant women, and vertical transmission". Result and discussion: The SARS-CoV-2 virus is unlike its former analogs: SARS-CoV, and MERS-CoV in 2002 and 2012, respectively, or anything mankind has faced earlier concerning viciousness, global spread, and gravity of a causative agent. The current review has delved into articles published in various journals worldwide including the latest studies on the impact of COVID-19 on pregnant women and neonates and has discussed complications and challenges, psychological health, immunological response, vertical transmission, concurrent disorders, vaccine debate, management recommendations, recent news of the approval of COVID-19 vaccine for 6 months and older babies, and future perspectives.
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Background: A new type of Corona virus that is SARS-COV-2 called COVID-19 had a huge pandemic worldwide. On January 30, 2020 the World Health Organization (WHO) declared the outbreak of COVID19 as a public health emergency of international concern. Method(s): Descriptive and retrospective study carried out at general hospital, Sapthagiri institute of medical science and research centre from September 2020 to September 2021. Result(s): Among 153 tested neonates, 91 were SARS-COV-2 positive. Out of 91 (59%), most common symptom reported is respiratory distress in the form of TTNB (43%) and require respiratory support for longer period compared to COVID negative group. Conclusion(s): 55% of neonates were symptomatic and reported higher incidence of NICU admission rates in SARS-COV-2 positive neonates born to SARS-COV-2 infected mothers which is comparable to our study.Copyright © 2022 Scientific Publishers of India. All rights reserved.
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The COVID-19 pandemic spread around the world due to the enormous transmission of the SARS-CoV-2 among humans. COVID-19 represents a threat to global public health. The entry of this virus into cells is greatly facilitated by the presence of angiotensin-converting enzyme 2 (ACE2) in the cell membrane. Today we do not have a precise understanding of how this receptor expresses in the brain during human development and, as a consequence, we do not know whether neural cells in the developing brain are susceptible to infection. We review the knowledge about ACE2 expression in the developing human brain, with special attention to the fetal stage. This stage corresponds to the period of the cerebral cortex formation. Therefore, SARS-CoV-2 infection during the fetal period may alter the normal development of the cerebral cortex. Although few cases have been published demonstrating vertical transmission of SARS-CoV-2 infection, the large number of infected young people may represent a problem which requires health surveillance, due to the possibility of cognitive alterations and abnormalities in the development of cortical circuits that may represent a predisposition to mental problems later in life.Copyright © 2023, Instituto de Investigaciones Medicas. All rights reserved.
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In this paper, we formulate and analyze a class of discrete state-structured epidemic models that spread through both horizontal and vertical transmissions on networks, where infected individuals can move from one infected state to any other state so that our models include all possible state-transfers (disease deterioration and amelioration) among different states. Many epidemic transmissions with or without vertical transmission in nature can be analyzed by referring to our models, such as HIV-1, viral hepatitis, and Covid-19. We derive the basic reproduction number R0= Rh+ Rv, and prove that the global dynamics are completely determined by the basic reproduction number: if R0 ≤ 1, the disease-free equilibrium is globally asymptotically stable and the disease always dies out;if R0 > 1, the disease-free equilibrium is unstable, and there exists a unique endemic equilibrium that is globally asymptotically stable, and the disease persists at a positive level in the population. It also implies that vertical transmission has an impact on maintaining infectious diseases when horizontal transmission cannot sustain the disease on its own. The proof of global stability is based on the graph-theoretic approach and answer the open problem left in [1]. Finally, numerical simulations are performed to illustrate the theoretical results. © 2023 American Institute of Mathematical Sciences. All rights reserved.
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The coronavirus disease 2019 (Covid-19), that was later declared pandemic by World Health Organization, had led to panic and fear worldwide. Like many outbreaks caused by viruses, in cheif reason for fear was the infectious agent's potential to be transmitted from pregnant women to their fetuses and newborns. In our study, the hospital records of 117 pregnant women who delivered stillbirths in our clinic between 01.01.2015 and 31.12.2020 were examined. The pregnancy characteristics and perinatal outcomes were examined by making retrospective analysis of the records. Considering six year of the study data, it was observed that the stillbirth rates increased in the pandemic period. One hundred seventeen stillbirth cases that occurred in the last six years were analyzed. The mean age of the pregnant women was 29.64+6 (18-44) and parity was 2.54+1.58 (1-8). Body mass index was calculated as 21.36+3.40 (16-27) average and smoking consumption rate was 9.40% (11/117). Maternal diabetes was detected in 8.54% of the patients (10/117) and pregnancies were complicated by maternal hypertension in 5.12% of the patients (6/117). The average birth weight was 1597+1038 (500-4700) gram. Sixty percent of the deliveries (n=71) were performed by vaginally. Fetal sex was 52.1% male (n=61). The number of deliveries in the past six years was 11780. Almost 1% of the deliveries occurred as stillbirths (117/11780). The unusual stillbirth ratio during the pandemic was 3.1 times higher than the average of pre-pandemic period (2.5vs0.80). In our study, we investigated stillbirth rates before and during the pandemic. Although vertical transmission of Covid-19 has not been reported, the adverse pregnancy and neonatal outcomes have been provided in many studies. Undoubtedly, in obstetrical practice stillbirth is one of the most destructive consequences for pregnant women. Considering the increase in stillbirth rates, we think that pregnant women with adverse perinatal outcomes should be routinely tested for Covid-19, especially during the outbreak.Copyright © 2021 Necati Ozpinar. All rights reserved.