Preparing for influenza after 2009 H1N1: special considerations for pregnant women and newborns

Influenza in Pregnancy: Maternal, Obstetric, and Fetal Implications, Diagnosis, and Management

Influenza(flu) in pregnancy is associated with higher rates of hospitalization, ICU admission, and death and with increased odds of congenital anomalies and stillbirth, but not preterm birth. Clinical manifestations of flu in pregnancy are the same as nonpregnant patients. Pregnant individuals with flu-like symptoms or flu exposure should be treated with antivirals. Diagnostic testing is not needed. Oseltamivir is the mainstay of treatment(and prophylaxis), and when given within 48 hours of symptom onset, it decreases morbidity and mortality. Influenza is associated with worse maternal, obstetric, and neonatal outcomes. These risks are mitigated by early oseltamivir treatment and maternal vaccination; hence the recommendation for universal vaccination in pregnancy.

Pregnancy, infection, and epigenetic regulation: A complex scenario

A unique immunological condition, pregnancy ensures fetus from maternal rejection, allows adequate fetal development, and protects against microorganisms. Infections during pregnancy may lead to devastating consequences for pregnant women and fetuses, resulting in the mother's death, miscarriage, premature childbirth, or neonate with congenital infection and severe diseases and defects. Epigenetic (heritable changes in gene expression) mechanisms like DNA methylation, chromatin modification, and gene expression modulation during gestation are linked with the number of defects in the fetus and adolescents. The feto-maternal crosstalk for fetal survival during the entire gestational stages are tightly regulated by various cellular pathways, including epigenetic mechanisms that respond to both internal as well outer environmental factors, which can influence the fetal development across the gestational stages. Due to the intense physiological, endocrinological, and immunological changes, pregnant women are more susceptible to bacterial, viral, parasitic, and fungal infections than the general population. Microbial infections with viruses (LCMV, SARS-CoV, MERS-CoV, and SARS-CoV-2) and bacteria (Clostridium perfringens, Coxiella burnetii, Listeria monocytogenes, Salmonella enteritidis) further increase the risk to maternal and fetal life and developmental outcome. If the infections remain untreated, the possibility of maternal and fetal death exists. This article focused on the severity and susceptibility to infections caused by Salmonella, Listeria, LCMV, and SARS-CoV-2 during pregnancy and their impact on maternal health and the fetus. How epigenetic regulation during pregnancy plays a vital role in deciding the fetus's developmental outcome under various conditions, including infection and other stress. A better understanding of the host-pathogen interaction, the characterization of the maternal immune system, and the epigenetic regulations during pregnancy may help protect the mother and fetus from infection-mediated outcomes.

International Registry of Coronavirus Exposure in Pregnancy (IRCEP): Cohort Description and Methodological Considerations

Limited data are available about the potential health effects of infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on pregnant women and their developing offspring. We developed the International Registry of Coronavirus Exposure in Pregnancy (IRCEP) to provide data on the risk of major adverse obstetric and neonatal outcomes among women with varying degrees of severity and timing of COVID-19 exposure during pregnancy. We describe here the cohort and share the lessons learned. The IRCEP enrolls women tested for SARS-CoV-2 or with a clinical diagnosis of COVID-19 during pregnancy and obtains information using an online data collection system. By March 2021, 17,532 participants from 77 countries had enrolled; 54% enrolled during pregnancy and 46% afterwards. Among women with symptomatic COVID-19 with a positive SARS-CoV-2 test (N=4,934), symptoms were mild in 41%, moderate in 52% and severe in 7%; 7.7% were hospitalized for COVID-19 and 1.7% were admitted to an intensive care unit. The biggest challenges were retention of participants enrolled during pregnancy, and the potential bias introduced when participants enroll after pregnancy outcomes are known. Multiple biases need to be considered and addressed when estimating and interpreting the effects of COVID-19 in pregnancy in these types of cohorts.

Paradox of COVID-19 in pregnancy: are pregnant women more protected against or at elevated risk of severe COVID-19?

Many underlying medical conditions have been linked to worse COVID-19 prognosis. Based on reports on SARS-CoV-1 and Middle East respiratory syndrome infections, pregnancy has been considered a predisposing factor to severe COVID-19, with pregnant women being a high-risk group for several physiological reasons. Specifically, pregnant women undergo physiological adaptations that predispose them to severe respiratory viral diseases, including SARS-CoV-2. However, a significant amount of evidence suggests that the clinical outcome of COVID-19 among pregnant women is not different from the general population. In view of this, this report discusses the physiological conditions in pregnant women that adversely affect their immunity, cardiovascular homeostasis, and their endothelial and coagulopathic functions, thereby making them more prone to severe viral infections. We also discuss how these physiological adaptations appear to paradoxically offer protection against severe COVID-19 among pregnant women.

Clinical and Pregnancy Outcomes of Coronavirus Disease 2019 Among Hospitalized Pregnant Women in the United States

BACKGROUND

Pregnant women with coronavirus disease 2019 (COVID-19) may be at greater risk of poor maternal and pregnancy outcomes. This retrospective analysis reports clinical and pregnancy outcomes among hospitalized pregnant women with COVID-19 in the United States.

METHODS

The Premier Healthcare Database-Special Release was used to examine the impact of COVID-19 among pregnant women aged 15-44 years who were hospitalized and who delivered compared with pregnant women without COVID-19. Outcomes evaluated were COVID-19 clinical progression, including the use of supplemental oxygen therapy, intensive care unit admission, critical illness, receipt of invasive mechanical ventilation/extracorporeal membrane oxygenation, maternal death, and pregnancy outcomes, including preterm delivery and stillbirth.

RESULTS

Overall, 473 902 hospitalized pregnant women were included, 8584 (1.8%) of whom had a COVID-19 diagnosis (mean age = 28.4 [standard deviation = 6.1] years; 40% Hispanic). The risk of poor clinical and pregnancy outcomes was greater among pregnant women with COVID-19 compared with pregnant women without a COVID-19 diagnosis in 2020; the risk of poor clinical and pregnancy outcomes increased with increasing age. Hispanic and Black non-Hispanic women were consistently observed to have the highest relative risk of experiencing poor clinical or pregnancy outcomes across all age groups.

CONCLUSIONS

Overall, COVID-19 had a significant negative impact on maternal health and pregnancy outcomes. These data help inform clinical practice and counseling to pregnant women regarding the risks of COVID-19. Clinical studies evaluating the safety and efficacy of vaccines against severe acute respiratory syndrome coronavirus 2 in pregnant women are urgently needed.

Emergency Preparedness and Response: Highlights from the Division of Reproductive Health, 2011-2021

This report provides historical context and rationale for coordinated, systematic, and evidence-based public health emergency preparedness and response (EPR) activities to address the needs of women of reproductive age. Needs of pregnant and postpartum women, and infants-before, during, and after public health emergencies-are highlighted. Four focus areas and related activities are described: (1) public health science; (2) clinical guidance; (3) partnerships, communication, and outreach; and (4) workforce development. Finally, the report summarizes major activities of the Division of Reproductive Health's EPR Team at the Centers for Disease Control and Prevention.

Influenza

Seasonal influenza epidemics of variable severity pose challenges to public health. Annual vaccination is the primary way to prevent influenza, and a wide range of vaccines are available, including inactivated or live attenuated standard-dose, recombinant vaccines, as well as adjuvanted or high-dose vaccines for persons aged 65 years or older. Persons at increased risk for influenza complications include young children, persons with underlying medical conditions, and older adults. Prompt diagnosis of influenza can facilitate early initiation of antiviral treatment that provides the greatest clinical benefit. This article summarizes recommendations for providers on influenza vaccination, diagnostic testing, and antiviral treatment.

Clinical Profiles, Demographic Features, and Maternal Outcomes among Coronavirus Disease Positive Pregnant Women: A Cross-sectional Study

BACKGROUND: Pregnant women are susceptible to coronavirus infection due to physiological changes in the circulatory and immunological parameters. AIM: The current study aimed to determine the demographic factors, clinical symptoms, and fetal-maternal outcomes and also compare the blood parameters and chest X-ray results among coronavirus disease 2019 (COVID-19) positive and negative pregnant women. MATERIALS AND METHODS: Complete blood count and Chest X-rays were performed as a routine in all pregnant women. Polymerase chain reaction for COVID-19 was performed for all women and the newborn. RESULTS: The blood parameters revealed that a significantly greater proportion of COVID-19 positive pregnant women had abnormal hemoglobin, total leukocyte count, neutrophil count, lymphocyte count, monocyte count, bilirubin, aspartate aminotransferase, alanine aminotransferase, and urea. CONCLUSIONS: The present study provided crucial insights into epidemiological and clinical features during the perinatal period. Chest X-rays and blood routine examination are reliable findings to prevent COVID-19 complications among pregnant women.

Influenza Illness and Partial Vaccination in the First Two Years of Life

More information about influenza in low- and middle-income countries could guide the establishment of pediatric influenza vaccine programs. This study (1) characterizes the burden of influenza in infants, and (2) compares signs and symptoms by prior influenza vaccination or influenza illness. Newborns from Managua, Nicaragua, were followed for two years. Data came from primary medical appointments, PCR testing, and parents’ daily symptom diaries. Logistic regression models estimated associations between preceding vaccination or illness and influenza incidence. Linear models compared duration of illness by prior vaccination or influenza illness. Among 833 infants, 31% had PCR-positive influenza, and 28% were vaccinated against influenza. Four (<0.5%) were fully vaccinated. Overall, influenza incidence was 21.0 (95% confidence interval (CI): 18.8, 23.2) per 100 person-years. Incidence was lower among those with prior influenza compared with those without preceding illness or vaccination (OR: 0.64, 95% CI: 0.44, 0.94). Partially vaccinated children had 1 day less fever than those without prior illness or vaccination (p = 0.049). A large proportion of children <2 years in Nicaragua contract influenza. Illness was attenuated for those partially vaccinated. Since few children were fully vaccinated, future studies will need to consider the effectiveness of a two-dose vaccination schedule.

Available medications used as potential therapeutics for COVID-19: What are the known safety profiles in pregnancy

BACKGROUND

Medications already available to treat other conditions are presently being studied in clinical trials as potential treatments for COVID-19. Given that pregnant women are excluded from these trials, we aimed to investigate their safety when used during pregnancy within a unique population source.

METHODS

Using the population-based Quebec Pregnancy Cohort, we identified women who delivered a singleton liveborn (1998-2015). Taking potential confounders into account including indications for use, the risk of prematurity, low birth weight (LBW), small for gestational age (SGA), and major congenital malformation (MCM) associated with COVID-19 repurposed drug use during pregnancy were quantified using generalized estimation equations.

RESULTS

Of the 231,075 eligible pregnancies, 107 were exposed to dexamethasone (0.05%), 31 to interferons (0.01%), 1,398 to heparins (0.60%), 24 to angiotensin-receptor blockers (ARB) (0.01%), 182 to chloroquine (0.08%), 103 to hydroxychloroquine (0.05%), 6,206 to azithromycin (2.70%), 230 to oseltamivir (0.10%), and 114 to HIV medications (0.05%). Adjusting for potential confounders, we observed an increased risk of prematurity related to dexamethasone (aOR 1.92, 95%CI 1.11-3.33; 15 exposed cases), anti-thrombotics (aOR 1.58, 95%CI 1.31-1.91; 177 exposed cases), and HIV medications (aOR 2.04, 95%CI 1.01-4.11; 20 exposed cases) use. An increased risk for LBW associated with anti-thrombotics (aOR 1.72, 95%CI 1.41-2.11; 152 exposed cases), and HIV medications (aOR 2.48, 95%CI 1.25-4.90; 21 exposed cases) use were also found. Gestational exposure to anti-thrombotics (aOR 1.20, 95%CI 1.00-1.44; 176 exposed cases), and HIV medications (aOR 2.61, 95%CI 1.51-4.51; 30 exposed cases) were associated with SGA. First-trimester dexamethasone (aOR 1.66, 95%CI 1.02-2.69; 20 exposed cases) and azithromycin (aOR 1.10, 95%CI 1.02-1.19; 747 exposed cases) exposures were associated with MCM.

CONCLUSIONS

Many available medications considered as treatments for COVID-19 are associated with adverse pregnancy outcomes. Caution is warranted when considering these medications during the gestational period.

Clinical characteristics and risk factors for SARS-CoV-2 infection in pregnant women attending a third level reference center in Mexico City

BACKGROUND

COVID-19 symptoms vary widely among pregnant women. We aimed to assess the most frequent symptoms amongst pregnant women with SARS-CoV-2 infection in a tertiary hospital in Mexico City.

METHODS

A cross-sectional study of pregnant women attending the National Institute of Perinatology in Mexico City was performed. All women who attended the hospital, despite their symptoms, were tested for SARS-CoV-2. A multivariate-age-adjusted logistic regression was used to assess the association between the main outcome and each characteristic of the clinical history.

RESULTS

A total of 1880 women were included in the data analysis. Among all women, 30.74% (n = 578) had a positive PCR for SARS-CoV-2 from which 2.7 (n = 50) were symptomatic. Symptoms associated with a positive PCR result were headache (p=.01), dyspnea (p=.043), and myalgia (p=.043).

CONCLUSIONS

At universal screening for SARS-CoV-2, one-third of the population had a positive result, while those symptoms associated with a positive PCR were headache, dyspnea, and myalgia.

PTSD in the COVID-19 Era

BACKGROUND

In December 2019, Wuhan City in Hubei Province, China witnessed an outbreak of a novel type of coronavirus (COVID-19), named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The sharp rise in the number of infected cases and the surge spike in fatalities worldwide prompted the World Health Organization (WHO) to declare this rapid outbreak a global pandemic in March 2020. The economic, health, and social ramifications of COVID-19 induced fear and anxiety all over the world.

OBJECTIVE

The purpose of this review is to discuss how precautionary measures and restrictions imposed by governments, such as quarantines, lockdowns, and social distancing, have not only caused economic losses, but also a rise in mental health problems specifically post-traumatic stress disorder (PTSD).

METHODS

A deep comprehensive review of the relevant literature regarding the pandemic and its debilitating consequences on the psychological status of the public was performed.

RESULTS

This review illustrates that the pandemic had a traumatic impact on the psychological functioning of the public, particularly COVID-19 survivors, older adults, and healthcare workers, due to difficulties in coping with new realities and uncertainties.

CONCLUSION

In this review, we have discussed the psychological implications of this pandemic and we have provided an extensive background for understanding options regarding PTSD management in healthy individuals and those with preexisting conditions.

The Changing Aspects of Motherhood in Face of the COVID-19 Pandemic in Low- and Middle-Income Countries

Purpose

To advocate perspectives to strengthen existing healthcare systems to prioritize maternal health services amidst and beyond the COVID-19 pandemic in low- and middle income countries.

Description

COVID-19 directly affects pregnant women causing more severe disease and adverse pregnancy outcomes. The indirect effects due to the monumental COVID-19 response are much worse, increasing maternal and neonatal mortality.

Assessment

Amidst COVID-19, governments must balance effective COVID-19 response measures while continuing delivery of essential health services. Using the World Health Organization’s operational guidelines as a base, countries must conduct contextualized analyses to tailor their operations. Evidence based information on different services and comparative cost-benefits will help decisions on trade-offs. Situational analyses identifying extent and reasons for service disruptions and estimates of impacts using modelling techniques will guide prioritization of services. Ensuring adequate supplies, maintaining core interventions, expanding non-physician workforce and deploying telehealth are some adaptive measures to optimize care. Beyond the COVID-19 pandemic, governments must reinvest in maternal and child health by building more resilient maternal health services supported by political commitment and multisectoral engagement, and with assistance from international partners.

Conclusions

Multi-sectoral investments providing high-quality care that ensures continuity and available to all segments of the population are needed. A robust primary healthcare system linked to specialist care and accessible to all segments of the population including marginalized subgroups is of paramount importance. Systematic approaches to digital health care solutions to bridge gaps in service is imperative. Future pandemic preparedness programs must include action plans for resilient maternal health services.

Attitudes and precaution practices towards COVID-19 among pregnant women in Singapore: a cross-sectional survey

Background

COVID-19 may predispose pregnant women to higher risks of severe disease and poorer neonatal outcome. Psychological sequalae of this pandemic may pose a greater conundrum than its clinical aspects. It is currently unknown that how pregnant women cope with this global pandemic and its ramifications. The aims of the study are to understand the attitudes and precaution practices of non-infected pregnant women towards the COVID-19 outbreak in Singapore.

Methods

An online cross-sectional survey of COVID-19 awareness among pregnant women attending antenatal clinics in Singapore was conducted. An internet link was provided to complete an online electronic survey on Google platform using a quick response (QR) code on mobile devices. The online survey consists of 34 questions that were categorized into 4 main sections, namely 1) social demographics 2) attitude on safe distancing measures 3) precaution practices and 4) perceptions of COVID-19. Multiple linear regression analysis was performed to examine women’s precaution practices among six independent socio-demographic variables, including age, ethnicity, education, front-line jobs, history of miscarriage and type of antenatal clinic (general, high risk).

Results

A total of 167 survey responses were obtained over 8 weeks from April to June 2020. The majority of women were aged ≤35 years (76%, n = 127), were of Chinese ethnicity (55%, n = 91), attained tertiary education (62%, n = 104) and were not working as frontline staff (70%). Using multiple linear regression models, Malay ethnicity (vs. Chinese, β 0.24; 95% CI 0.04, 0.44) was associated with higher frequency of practicing social distancing. Malay women (β 0.48; 95% CI 0.16, 0.80) and those who worked as frontline staff (β 0.28; 95% CI 0.01, 0.56) sanitized their hands at higher frequencies. Age of ≥36 years (vs. ≤30 years, β 0.24; 95% CI 0.01, 0.46), Malay (vs. Chinese, β 0.27; 95% CI 0.06, 0.48) and Indian ethnicity (vs. Chinese, β 0.41; 95% CI 0.02, 0.80), and attendance at high-risk clinic (vs. general clinic, β 0.20; 95% CI 0.01, 0.39) were associated with higher frequency of staying-at-home.

Conclusion

Social demographical factors including age > 36 years old, Malay ethnicity, employment in front line jobs and attendance at high-risk clinics are likely to influence the attitudes and precaution practices among pregnant women towards COVID-19 in Singapore. Knowledge gained from our cross-sectional online survey can better guide clinicians to communicate better with pregnant women. Hence, it is important for clinicians to render appropriate counselling and focused clarification on the effect of COVID-19 among pregnant women for psychological support and mental well being.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-020-03378-w.

Pregnancy, Viral Infection, and COVID-19

Pregnancy comprises a unique immunological condition, to allow fetal development and to protect the host from pathogenic infections. Viral infections during pregnancy can disrupt immunological tolerance and may generate deleterious effects on the fetus. Despite these possible links between pregnancy and infection-induced morbidity, it is unclear how pregnancy interferes with maternal response to some viral pathogens. In this context, the novel coronavirus (SARS-CoV-2) can induce the coronavirus diseases-2019 (COVID-19) in pregnant women. The potential risk of vertical transmission is unclear, babies born from COVID-19-positive mothers seems to have no serious clinical symptoms, the possible mechanisms are discussed, which highlights that checking the children's outcome and more research is warranted. In this review, we investigate the reports concerning viral infections and COVID-19 during pregnancy, to establish a correlation and possible implications of COVID-19 during pregnancy and neonatal's health.

Plague and Pregnancy: Why Special Considerations Are Needed

Pregnant women are an important at-risk population to consider during public health emergencies. These women, like nonpregnant adults, may be faced with the risk of acquiring life-threatening infections during outbreaks or bioterrorism (BT) events and, in some cases, can experience increased severity of infection and higher morbidity compared with nonpregnant adults. Yersinia pestis, the bacterium that causes plague, is a highly pathogenic organism. There are 4 million births annually in the United States, and thus the unique needs of pregnant women and their infants should be considered in pre-event planning for a plague outbreak or BT event.

Coronavirus Disease 2019 (COVID-19) and Pregnancy: Responding to a Rapidly Evolving Situation

As the world confronts coronavirus disease 2019 (COVID-19), an illness caused by yet another emerging pathogen (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]), obstetric care providers are asking what this means for pregnant women. The global spread has been swift, and many key questions remain. The case-fatality rate for persons cared for in the United States and whether asymptomatic persons transmit the virus are examples of questions that need to be answered to inform public health control measures. There are also unanswered questions specific to pregnant women, such as whether pregnant women are more severely affected and whether intrauterine transmission occurs. Although guidelines for pregnant women from the American College of Obstetricians and Gynecologists and the Centers for Disease Control and Prevention have been rapidly developed based on the best available evidence, additional information is critically needed to inform key decisions, such as whether pregnant health care workers should receive special consideration, whether to temporarily separate infected mothers and their newborns, and whether it is safe for infected women to breastfeed. Some current recommendations are well supported, based largely on what we know from seasonal influenza: patients should avoid contact with ill persons, avoid touching their face, cover coughs and sneezes, wash hands frequently, disinfect contaminated surfaces, and stay home when sick. Prenatal clinics should ensure all pregnant women and their visitors are screened for fever and respiratory symptoms, and symptomatic women should be isolated from well women and required to wear a mask. As the situation with COVID-19 rapidly unfolds, it is critical that obstetricians keep up to date.

Coronavirus Disease 2019 (COVID-19) and pregnancy: what obstetricians need to know

Coronavirus disease 2019 is an emerging disease with a rapid increase in cases and deaths since its first identification in Wuhan, China, in December 2019. Limited data are available about coronavirus disease 2019 during pregnancy; however, information on illnesses associated with other highly pathogenic coronaviruses (ie, severe acute respiratory syndrome and the Middle East respiratory syndrome) might provide insights into coronavirus disease 2019's effects during pregnancy. Coronaviruses cause illness ranging in severity from the common cold to severe respiratory illness and death. Currently the primary epidemiologic risk factors for coronavirus disease 2019 include travel from mainland China (especially Hubei Province) or close contact with infected individuals within 14 days of symptom onset. Data suggest an incubation period of ∼5 days (range, 2-14 days). Average age of hospitalized patients has been 49-56 years, with a third to half with an underlying illness. Children have been rarely reported. Men were more frequent among hospitalized cases (54-73%). Frequent manifestations include fever, cough, myalgia, headache, and diarrhea. Abnormal testing includes abnormalities on chest radiographic imaging, lymphopenia, leukopenia, and thrombocytopenia. Initial reports suggest that acute respiratory distress syndrome develops in 17-29% of hospitalized patients. Overall case fatality rate appears to be ∼1%; however, early data may overestimate this rate. In 2 reports describing 18 pregnancies with coronavirus disease 2019, all were infected in the third trimester, and clinical findings were similar to those in nonpregnant adults. Fetal distress and preterm delivery were seen in some cases. All but 2 pregnancies were cesarean deliveries and no evidence of in utero transmission was seen. Data on severe acute respiratory syndrome and Middle East respiratory syndrome in pregnancy are sparse. For severe acute respiratory syndrome, the largest series of 12 pregnancies had a case-fatality rate of 25%. Complications included acute respiratory distress syndrome in 4, disseminated intravascular coagulopathy in 3, renal failure in 3, secondary bacterial pneumonia in 2, and sepsis in 2 patients. Mechanical ventilation was 3 times more likely among pregnant compared with nonpregnant women. Among 7 first-trimester infections, 4 ended in spontaneous abortion. Four of 5 women with severe acute respiratory syndrome after 24 weeks' gestation delivered preterm. For Middle East respiratory syndrome, there were 13 case reports in pregnant women, of which 2 were asymptomatic, identified as part of a contact investigation; 3 patients (23%) died. Two pregnancies ended in fetal demise and 2 were born preterm. No evidence of in utero transmission was seen in severe acute respiratory syndrome or Middle East respiratory syndrome. Currently no coronavirus-specific treatments have been approved by the US Food and Drug Administration. Because coronavirus disease 2019 might increase the risk for pregnancy complications, management should optimally be in a health care facility with close maternal and fetal monitoring. Principles of management of coronavirus disease 2019 in pregnancy include early isolation, aggressive infection control procedures, oxygen therapy, avoidance of fluid overload, consideration of empiric antibiotics (secondary to bacterial infection risk), laboratory testing for the virus and coinfection, fetal and uterine contraction monitoring, early mechanical ventilation for progressive respiratory failure, individualized delivery planning, and a team-based approach with multispecialty consultations. Information on coronavirus disease 2019 is increasing rapidly. Clinicians should continue to follow the Centers for Disease Control and Prevention website to stay up to date with the latest information (https://www.cdc.gov/coronavirus/2019-nCoV/hcp/index.html).

Retrospective study showed that bacterial gastroenteritis was an important cause of bloody stools in newborn infants

AIM

Acute bacterial gastroenteritis is a major cause of morbidity and mortality, especially in the developing countries. We examined the incidence, clinical features and outcomes in the first week of life.

METHODS

This was a retrospective study of culture-proven bacterial gastroenteritis in newborn infants that were diagnosed between January 2011 and September 2018 in a tertiary centre in Israel.

RESULTS

There were 10 cases of culture-proven bacterial gastroenteritis, detected out of 91 stool cultures. All infants were born vaginally and nine were full-term infants. The annual incidence was 0.096 per 1000 live births. The responsible pathogen was Campylobacter in six patients, Salmonella in two and Shigella sonnei in two. The mean age of disease onset was two days of life. Antibiotics were given to five patients, but were inappropriate in two cases. Only one patient with the Shigella sonnei infection required respiratory support. All patients fully recovered.

CONCLUSION

One in ten newborn infants with bloody stools had bacterial gastroenteritis, contradicting the low rates found in other studies and indicating the importance of considering this diagnosis. Antimicrobials active against Salmonella or Shigella should be given to newborn infants who have bloody stools and look ill.

Clinical Practice Guidelines by the Infectious Diseases Society of America: 2018 Update on Diagnosis, Treatment, Chemoprophylaxis, and Institutional Outbreak Management of Seasonal Influenzaa

These clinical practice guidelines are an update of the guidelines published by the Infectious Diseases Society of America (IDSA) in 2009, prior to the 2009 H1N1 influenza pandemic. This document addresses new information regarding diagnostic testing, treatment and chemoprophylaxis with antiviral medications, and issues related to institutional outbreak management for seasonal influenza. It is intended for use by primary care clinicians, obstetricians, emergency medicine providers, hospitalists, laboratorians, and infectious disease specialists, as well as other clinicians managing patients with suspected or laboratory-confirmed influenza. The guidelines consider the care of children and adults, including special populations such as pregnant and postpartum women and immunocompromised patients.

Clinical Practice Guidelines by the Infectious Diseases Society of America: 2018 Update on Diagnosis, Treatment, Chemoprophylaxis, and Institutional Outbreak Management of Seasonal Influenzaa

These clinical practice guidelines are an update of the guidelines published by the Infectious Diseases Society of America (IDSA) in 2009, prior to the 2009 H1N1 influenza pandemic. This document addresses new information regarding diagnostic testing, treatment and chemoprophylaxis with antiviral medications, and issues related to institutional outbreak management for seasonal influenza. It is intended for use by primary care clinicians, obstetricians, emergency medicine providers, hospitalists, laboratorians, and infectious disease specialists, as well as other clinicians managing patients with suspected or laboratory-confirmed influenza. The guidelines consider the care of children and adults, including special populations such as pregnant and postpartum women and immunocompromised patients.

Outcomes of infants born to women with influenza A(H1N1)pdm09

BACKGROUND

Pregnant women with influenza are more likely to have complications, but information on infant outcomes is limited.

METHODS

Five state/local health departments collected data on outcomes of infants born to pregnant women with 2009 H1N1 influenza reported to the Centers for Disease Control and Prevention from April to December 2009. Collaborating sites linked information on pregnant women with confirmed 2009 H1N1 influenza, many who were severely ill, to their infants' birth certificates. Collaborators also collected birth certificate data from two comparison groups that were matched with H1N1-affected pregnancies on month of conception, sex, and county of residence.

RESULTS

490 pregnant women with influenza, 1,451 women without reported influenza with pregnancies in the same year, and 1,446 pregnant women without reported influenza with prior year pregnancies were included. Women with 2009 H1N1 influenza admitted to an intensive care unit (ICU; n = 64) were more likely to deliver preterm infants (<37 weeks), low birth weight infants, and infants with Apgar scores <=6 at 5 min than women in comparison groups (adjusted relative risk, aRR = 3.9 [2.7, 5.6], aRR = 4.6 [2.9, 7.5], and aRR = 8.7 [3.6, 21.2], for same year comparisons, respectively). Women with influenza who were not hospitalized and hospitalized women not admitted to the ICU did not have significantly elevated risks for adverse infant outcomes.

CONCLUSIONS

Severely ill women with 2009 H1N1 influenza during pregnancy were more likely to have adverse birth outcomes than women without influenza, providing more support for influenza vaccination during pregnancy.

Exploring the risk of severe outcomes and the role of seasonal influenza vaccination in pregnant women hospitalized with confirmed influenza, Spain, 2010/11-2015/16

Based on previous observations during pandemics and seasonal epidemics, pregnant women are considered at risk of developing severe influenza outcomes after influenza infection. With the aim of preventing severe influenza illness, the World Health Organization (WHO) includes pregnant women as a target group for seasonal influenza vaccination. However, influenza vaccine uptake during pregnancy remains low in many countries, including Spain. The objectives of this study were to increase the evidence of pregnancy as a risk factor for severe influenza illness and to study the potential role of seasonal influenza vaccination in the prevention of severe outcomes in infected pregnant women. Using information from the surveillance of Severe Hospitalized Confirmed Influenza Cases (SHCIC) in Spain, from seasons 2010/11 to 2015/16, we estimated that pregnant women in our study had a relative risk of hospitalization with severe influenza nearly 7.8 times higher than non-pregnant women of reproductive age. Only 5 out of 167 pregnant women with known vaccination status in our study had been vaccinated (3.6%). Such extremely low vaccination coverage only allowed obtaining crude estimates suggesting a protective effect of the vaccine against influenza complications (ICU admission or death). Our overall results support that pregnant women could benefit from seasonal influenza vaccination, in line with national and international recommendations.

Herpes simplex virus type 2 IgG antibodies in sera of umbilical cord as a proxy for placental infection in asymptomatic pregnant women

PROBLEM

Herpes simplex virus type 2 (HSV-2) infection is one of the most prevalent diseases worldwide and is mainly sexually transmitted. When infecting pregnant women, HSV-2 is able to infect the placenta, can reach the fetus, and may affect the fetal development. We sought to determine the prevalence of HSV-2 infection and reactivation in asymptomatic pregnant women, the correlation between IgG in the maternal circulation and cord blood, and the correlation between circulating IgG, placental, and newborn infection (blood cord).

METHOD OF STUDY

Serum samples and placental tissues from pregnant women and umbilical cord blood samples from their newborns were collected. Anti-HSV-2 antibodies were identified by ELISA, and HSV-2 DNA was detected by nested PCR.

RESULTS

The seropositivity of IgG in pregnant women was 29.7% and IgM was detected in 1 woman (0.5%). In the umbilical cord of newborns, 33.1% were IgG-positive and IgM was detected in 2 samples (1.5%). A positive correlation between HSV-2 IgG titers in serum from pregnant women and cord blood samples was found (r = .36, P = .001). A difference between the positive and negative placental groups (maternal side) was found in titers of IgG in sera of umbilical cord, which were significantly higher in the positive placental group (P = .004).

CONCLUSION

We describe for the first time that newborns from mothers with HSV-2 placental infection have higher IgG titers in sera of umbilical cord, suggesting IgGs antibodies can be indicative of placental viral infection in asymptomatic women.

Risks associated with viral infections during pregnancy

Despite the prevalence of viral infections in the American population, we still have a limited understanding of how they affect pregnancy and fetal development. Viruses can gain access to the decidua and placenta by ascending from the lower reproductive tract or via hematogenous transmission. Viral tropism for the decidua and placenta is then dependent on viral entry receptor expression in these tissues as well as on the maternal immune response to the virus. These factors vary by cell type and gestational age and can be affected by changes to the in utero environment and maternal immunity. Some viruses can directly infect the fetus at specific times during gestation, while some only infect the placenta. Both scenarios can result in severe birth defects or pregnancy loss. Systemic maternal viral infections can also affect the pregnancy, and these can be especially dangerous, because pregnant women suffer higher virus-associated morbidity and mortality than do nonpregnant counterparts. In this Review, we discuss the potential contributions of maternal, placental, and fetal viral infection to pregnancy outcome, fetal development, and maternal well-being.

Cutting Edge: Fetal/Placental Type I IFN Can Affect Maternal Survival and Fetal Viral Load during Viral Infection

Pregnant women have greater mortality and complications associated with viral infections compared with the general population, but the reason for the increased susceptibility is not well defined. Placenta type I IFN is an important immune modulator and protects the pregnancy. We hypothesized that loss of placental IFN affects the regulation of the maternal immune system, resulting in the differential response to infections observed in pregnancy. Pregnant mice lacking the IFN-α/β receptor (IFNAR) became viremic and had higher mortality compared with nonpregnant animals. Notably, an embryo with functional IFN signaling alone was sufficient to rescue the pregnant IFNAR-/- dam from virus-associated demise. Placental IFN was also an important regulator of viral replication in placental tissue and significantly affected viral transmission to the fetus. These findings highlight the role of fetal/placental IFN in the modulation of viral infection in the mother and fetus.

Zika Virus: An Emergence of a New Arbovirus

The world is facing a new pandemic in progress due to a mosquito-borne flavivirus popularly known as Zika virus. The emergence of this new virus is really alarming with the sudden increment in the cases of microcephaly reported from Brazil. The findings attributing the involvement of Zika virus as the reason for congenital deformations in the babies born in afflicted areas have really shocked the world. The present knowledge about this virus is very limited and in the absence of further studies the precautions seems to be the best way of protection from this virus. The present article is a short review about this new virus.

Update: Interim Guidelines for Health Care Providers Caring for Pregnant Women and Women of Reproductive Age with Possible Zika Virus Exposure - United States, 2016

CDC has updated its interim guidelines for U.S. health care providers caring for pregnant women during a Zika virus outbreak (1). Updated guidelines include a new recommendation to offer serologic testing to asymptomatic pregnant women (women who do not report clinical illness consistent with Zika virus disease) who have traveled to areas with ongoing Zika virus transmission. Testing can be offered 2-12 weeks after pregnant women return from travel. This update also expands guidance to women who reside in areas with ongoing Zika virus transmission, and includes recommendations for screening, testing, and management of pregnant women and recommendations for counseling women of reproductive age (15-44 years). Pregnant women who reside in areas with ongoing Zika virus transmission have an ongoing risk for infection throughout their pregnancy. For pregnant women with clinical illness consistent with Zika virus disease,* testing is recommended during the first week of illness. For asymptomatic pregnant women residing in areas with ongoing Zika virus transmission, testing is recommended at the initiation of prenatal care with follow-up testing mid-second trimester. Local health officials should determine when to implement testing of asymptomatic pregnant women based on information about levels of Zika virus transmission and laboratory capacity. Health care providers should discuss reproductive life plans, including pregnancy intention and timing, with women of reproductive age in the context of the potential risks associated with Zika virus infection.

Interim Guidelines for Pregnant Women During a Zika Virus Outbreak--United States, 2016

CDC has developed interim guidelines for health care providers in the United States caring for pregnant women during a Zika virus outbreak. These guidelines include recommendations for pregnant women considering travel to an area with Zika virus transmission and recommendations for screening, testing, and management of pregnant returning travelers. Updates on areas with ongoing Zika virus transmission are available online (http://wwwnc.cdc.gov/travel/notices/). Health care providers should ask all pregnant women about recent travel. Pregnant women with a history of travel to an area with Zika virus transmission and who report two or more symptoms consistent with Zika virus disease (acute onset of fever, maculopapular rash, arthralgia, or conjunctivitis) during or within 2 weeks of travel, or who have ultrasound findings of fetal microcephaly or intracranial calcifications, should be tested for Zika virus infection in consultation with their state or local health department. Testing is not indicated for women without a travel history to an area with Zika virus transmission. In pregnant women with laboratory evidence of Zika virus infection, serial ultrasound examination should be considered to monitor fetal growth and anatomy and referral to a maternal-fetal medicine or infectious disease specialist with expertise in pregnancy management is recommended. There is no specific antiviral treatment for Zika virus; supportive care is recommended.

Knowledge, Attitudes, and Practices of Obstetrician-Gynecologists Regarding Influenza Prevention and Treatment Following the 2009 H1N1 Pandemic

BACKGROUND

Pregnant women are at increased risk for complications associated with influenza. Influenza vaccination during pregnancy helps protect both pregnant women and infants less than 6 months of age from contracting the flu. This study investigated influenza prevention and treatment practices of obstetrician-gynecologists (ob-gyns) during the influenza season immediately following the 2009-2010 H1N1 season.

METHODS

In 2011, surveys were sent to two groups of Fellows of the American College of Obstetricians and Gynecologists. Group 1 was 907 ob-gyns who responded to our previous survey on practice and knowledge of influenza vaccination, diagnosis, and treatment during the 2009-2010 H1N1 influenza pandemic. Group 2 was 2,293 new recipients randomly selected from the American College of Obstetricians and Gynecologists database. Data were analyzed in 2013.

RESULTS

A high proportion of pregnant patients were reported to be vaccinated against influenza (71.7%); however, the data suggest that in general preventative practices decreased between the 2009-2010 H1N1 season and 2010-2011 season. A higher proportion of women eligible for Medicaid in a practice was associated with a lower estimate of vaccination rate. Ob-gyns with more than 20 years of practice were more likely to be concerned about the risks of antivirals and less likely to routinely prescribe them.

CONCLUSIONS

Ob-gyns may be overestimating the proportion of pregnant women being vaccinated. The gains in vaccination and influenza prevention practices from the H1N1 pandemic have not been completely retained. Discrepancies in the use of anti-virals to treat suspected or confirmed influenza in pregnant patients exist and need to be addressed.

The association between influenza vaccination and other preventative health behaviors in a cohort of pregnant women

OBJECTIVES

Although pregnant women are a high-priority group for seasonal influenza vaccination, vaccination rates in this population remain below target levels. Previous studies have identified sociodemographic predictors of vaccine choice, but relationships between preconception heath behaviors and seasonal influenza vaccination are poorly understood. This prospective cohort study followed pregnant women during the 2010-2011 influenza season to determine if certain health behaviors were associated with vaccination status.

METHOD

Participants were pregnant women receiving prenatal care from Kaiser Permanente Northwest and Kaiser Permanente Northern California. Women were surveyed about preconception smoking, alcohol consumption, and vitamin/supplement use. Vaccination data were obtained from health plan databases and state immunization records.

RESULTS

Data from 1,204 women were included in this analysis. Most participants (1,204; 66.4%) received a seasonal influenza vaccine during the study period. Women vaccinated prior to pregnancy were more likely to use a supplement containing folic acid (80%) or vitamin D (30%) compared with women who were vaccinated during pregnancy (72% and 15%, respectively) or unvaccinated women (62% and 12%, respectively, p < .001). Women vaccinated prior to or during pregnancy were more likely (75%) to have never smoked compared with women who were not vaccinated (70%, p = .005). There were no significant differences in alcohol use or household cigarette smoke exposure by vaccination group.

CONCLUSIONS

Women who engaged in specific preconception health behaviors were more likely to receive seasonal influenza vaccination. Failure to participate in these health behaviors could alert health care practitioners to patients' increased risk of remaining unvaccinated during pregnancy.

Factors associated with seasonal influenza vaccination in pregnant women

BACKGROUND

This observational study followed a cohort of pregnant women during the 2010-2011 influenza season to determine factors associated with vaccination.

METHODS

Participants were 1105 pregnant women who completed a survey assessing health beliefs related to vaccination upon enrollment and were then followed to determine vaccination status by the end of the 2010-2011 influenza season. We conducted univariate and multivariate analyses to explore factors associated with vaccination status and a factor analysis of survey items to identify health beliefs associated with vaccination.

RESULTS

Sixty-three percent (n=701) of the participants were vaccinated. In the univariate analyses, multiple factors were associated with vaccination status, including maternal age, race, marital status, educational level, and gravidity. Factor analysis identified two health belief factors associated with vaccination: participant's positive views (factor 1) and negative views (factor 2) of influenza vaccination. In a multivariate logistic regression model, factor 1 was associated with increased likelihood of vaccination (adjusted odds ratio [aOR]=2.18; 95% confidence interval [CI]=1.72-2.78), whereas factor 2 was associated with decreased likelihood of vaccination (aOR=0.36; 95% CI=0.28-0.46). After controlling for the two health belief factors in multivariate analyses, demographic factors significant in univariate analyses were no longer significant. Women who received a provider recommendation were about three times more likely to be vaccinated (aOR=3.14; 95% CI=1.99-4.96).

CONCLUSION

Pregnant women's health beliefs about vaccination appear to be more important than demographic and maternal factors previously associated with vaccination status. Provider recommendation remains one of the most critical factors influencing vaccination during pregnancy.

Pandemic influenza A (H1N1) infection in pregnant and nonpregnant women in Spain (2009-2010)

The present study aimed to compare the main features of infection with pandemic influenza A virus in pregnant and nonpregnant women admitted to hospitals in Spain during the first waves of the 2009-2010 influenza pandemic. This was a prospective (November 2009 to June 2010), multicenter observational study. All cases were women of reproductive age who had not been vaccinated against seasonal or pandemic influenza A. Influenza infection was confirmed by reverse transcription-polymerase chain reaction (RT-PCR). The sociodemographic and clinical data of all cases were reviewed. A total of 219 inpatients, including 49 pregnant women and 170 nonpregnant women, were enrolled in the study upon admission to participating hospitals. The most substantially different symptoms between the groups were respiratory distress and unilobar consolidation, both of which were more frequent among nonpregnant women. Antibiotics and systemic corticosteroids were more frequently used in nonpregnant women; however, there were no differences in the rates of treatment with antivirals. Our findings indicated that the compared with nonpregnant women, pregnant women in this study did not have significantly different symptoms and were not at increased risk of complications from pandemic influenza virus infection.

2009 A/H1N1 influenza vaccination in pregnancy: uptake and pregnancy outcomes - a historical cohort study

OBJECTIVES

To describe the uptake of 2009 A/H1N1 influenza vaccination among pregnant women and determine if vaccination was associated with adverse pregnancy outcomes.

STUDY DESIGN

A historical cohort study was performed using booking, delivery suite and neonatal unit discharge records from the Coombe Women and Infants University Hospital, Dublin, Ireland. Singleton deliveries to women pregnant before (December 2008-September 2009) and during the pandemic (December 2009-September 2010) were included. Information on vaccination status and type of vaccine was collected on admission to the delivery suite. Logistic regression analyses were used to determine maternal characteristics associated with vaccination. Pregnancy outcomes were compared for vaccinated and unvaccinated women, with adjustment for differing maternal characteristics. Outcomes included vaccination status, preterm birth, size for gestational age, neonatal intensive care admission, congenital anomalies and perinatal death.

RESULTS

Of 6894 women pregnant during the pandemic, 2996 [43.5%] reported vaccination at delivery. In the early weeks of the vaccination programme rates of over 70% were achieved. Of those vaccinated, 246 [8.2%], 1709 [57.0%] and 1034 [34.5%] were vaccinated in the first, second and third trimesters respectively. Vaccination was less likely in younger age groups, those who were not in the professional/manager/employer socioeconomic group, women from Eastern Europe, Africa and Asia/Middle East, those who reported an unplanned pregnancy, women who booked late for antenatal care and recipients of publicly-funded obstetric care. Irish nationality was associated with reporting vaccination. There was no association between vaccination during pregnancy and adverse pregnancy outcomes. Women who were vaccinated were less likely to have a preterm delivery than unvaccinated women.

CONCLUSION

2009 A/H1N1 influenza vaccination uptake was influenced by maternal sociodemographic factors. High vaccination uptake can be achieved in a pandemic situation. Future public health campaigns should provide clear information on vaccination safety in pregnancy, ensure consistent vaccination recommendations from healthcare professionals and provide easy access to vaccination in order to optimise uptake rates in subgroups of the population who less likely to be vaccinated. There was no association between vaccination and adverse pregnancy outcomes.

Trends in influenza vaccine coverage in pregnant women, 2008 to 2012

CONTEXT

Pregnant women are at increased risk of severe influenza-related complications and hospitalizations and are a priority group for influenza vaccination.

OBJECTIVE

To examine coverage of seasonal and pandemic influenza A (H1N1) vaccines in pregnant women in a managed care setting, from 2008 to 2012.

DESIGN

Retrospective cohort study of 10,145 pregnant women.

MAIN OUTCOME MEASURES

H1N1 and seasonal influenza vaccination rates.

RESULTS

Seasonal influenza vaccine coverage increased from 38% to 63% between the 2008-2009 and 2010-2011 seasons, and then dropped to 61% in 2011-2012. Vaccine coverage was higher in women considered at high risk of influenza complications, increasing from 43% in 2008-2009 to 71% in 2010-2011, before decreasing to 69% in 2011-2012. H1N1 vaccine coverage was greater than seasonal influenza coverage in 2009-2010 in the overall pregnant population (61% vs 53%) and in the high-risk group (64% vs 59%). We observed statistically significant differences in vaccination rates by trimester, gravidity, maternal age, and race/ethnicity.

CONCLUSIONS

Vaccination rates increased significantly from 2008 to 2011, then dropped slightly in 2011-2012. Continued efforts are needed to ensure adequate vaccination coverage in this high-risk population.

Predictors of seasonal influenza vaccination during pregnancy

OBJECTIVE

Although pregnant women are a high-priority group for influenza vaccination, vaccination rates in this population remain below recommended levels. This prospective cohort study followed a group of pregnant women during the 2010-2011 influenza season to determine possible predictors of vaccination.

METHODS

Participants were 552 pregnant women who had not already received the influenza vaccine at the time of enrollment. Women completed a survey assessing knowledge, attitudes, and beliefs about vaccination (based on the Health Belief Model) by telephone and were then followed to determine vaccination status by the end of the 2010-2011 influenza season.

RESULTS

Forty-six percent (n=252) of the women were vaccinated, and 54% (n=300) remained unvaccinated after enrollment in the study. Few baseline characteristics, with the exception of study site, month of enrollment, and maternal ethnicity, were predictive of vaccination status. Even after adjusting for significant baseline characteristics, we found that at least one item from each domain of the Health Beliefs Model was predictive of subsequent vaccination. Specifically, women who perceived they were susceptible to influenza, that they were at risk of getting seriously ill from influenza, that they would regret not getting vaccinated, and who trusted recommended guidelines about influenza vaccination during pregnancy were more likely to get vaccinated. Women who were concerned about vaccine side effects were less likely to get vaccinated.

CONCLUSION

Trust in recommendations, perceived susceptibility to and seriousness of influenza, perceived regret about not getting vaccinated, and vaccine safety concerns predict vaccination in pregnant women.

LEVEL OF EVIDENCE

II.

Acceptance and rejection of influenza vaccination by pregnant women in southern Iran: physicians' role and barriers

OBJECTIVE

Vaccination provides the most effective protection against maternal, fetal and neonatal complications of influenza infection. This study aimed to determine the uptake rate of influenza vaccination including 2009 pandemic H1N1 influenza and seasonal influenza vaccination and the reasons for acceptance or rejection among pregnant women.

RESULT

Mean age of the 416 pregnant women enrolled in this study was 27.06 ± 5.27 y. Only 25 (6%) of 397 women had history of vaccination. Of 383 (92.06%) pregnant women who had rejected vaccination, 116 (30.28%) declared that they lacked information about influenza vaccination and 44 (11.48%) felt that they did not need vaccination. Concerns about the safety of influenza vaccination were reported by only 2 women (0.52%). Of the 25 (6%) pregnant women who were vaccinated against influenza, 15 (60%) accepted because of advice they received from persons other than physicians, 5 (20%) believed that influenza vaccination is necessary for everyone, and 3 (12%) accepted because of a history of frequent influenza virus infections in previous years.

METHOD

This questionnaire based study was conducted at obstetrics and maternity hospitals affiliated with Shiraz University of Medical Sciences, Shiraz, Iran. Pregnant women were interviewed individually and privately. SPSS was used for data analysis.

CONCLUSION

Most of the unvaccinated and vaccinated pregnant women lacked sufficient knowledge about influenza. Education of pregnant women about influenza vaccination and encouragement from physicians may have a remarkable effect on turning poor compliance into high flu vaccination uptake among pregnant women.

Viral invasion of the amniotic cavity (VIAC) in the midtrimester of pregnancy

INTRODUCTION

The prevalence of viral infections in the amniotic fluid (AF) has not yet been ascertained. The aim of this study was to determine the prevalence of specific viral nucleic acids in the AF and its relationship to pregnancy outcome.

STUDY DESIGN

From a cohort of 847 consecutive women undergoing midtrimester amniocentesis, 729 cases were included in this study after exclusion of documented fetal anomalies, chromosomal abnormalities, unavailability of AF specimens and clinical outcomes. AF specimens were tested by quantitative real-time PCR for the presence of genome sequences of the following viruses: adenoviruses, herpes simplex virus (HSV), varicella zoster virus (VZV), human herpesvirus 6 (HHV6), human cytomegalovirus (HCMV), Epstein-Barr virus (EBV), parvovirus B19 and enteroviruses. Viral nucleic acid testing was also performed in maternal blood and cord blood in the population of women in whom AF was positive for viruses and in a control group of 29 women with AF negative for viral nucleic acids. The relationship between the presence of viruses and pregnancy and neonatal outcome was examined. The correlation between the presence of nucleic acids of viruses in the AF and the concentration of the cytokine interleukin-6 (IL-6) and the T cell chemokine CXCL-10 (or IP-10) in AF and maternal blood were analyzed.

RESULTS

Viral genome sequences were found in 16 of 729 (2.2%) AF samples. HHV6 was the most commonly detected virus (7 cases, 1.0%), followed by HCMV (6 cases, 0.8%), parvovirus B19 (2 cases, 0.3%) and EBV (1 case, 0.1%), while HSV, VZV, enteroviruses and adenoviruses were not found in this cohort. Corresponding viral DNA was also detected in maternal blood of six out of seven women with HHV6-positive AF and in the umbilical cord plasma, which was available in one case. In contrast, viral DNA was not detected in maternal blood of women with AF positive for parvovirus B19, HCMV, EBV or of women with AF negative for viruses. HHV6 genome copy number in AF and maternal blood was consistent with genomic integration of viral DNA and genetic infection in all women. There was no significant difference in the AF concentration of IL-6 and IP-10 between patients with and without VIAC. However, for HCMV, there was a significant relationship between viral copy number and IP-10 concentration in maternal blood and AF. The group of women with AF positive for viral DNA delivered at term healthy neonates without complications in 14 out of 16 cases. In one case of HHV6 infection in the AF, the patient developed gestational hypertension at term, and in another case of HHV6 infection in the AF, the patient delivered at 33 weeks after preterm premature rupture of membranes (PPROM).

CONCLUSION

Viral nucleic acids are detectable in 2.2% of AF samples obtained from asymptomatic women in the midtrimester. HHV6 was the most frequently detected virus in AF. Adenoviruses were not detected. Vertical transmission of HHV6 was demonstrated in one case.

Effects of influenza on pregnant women and infants

Influenza vaccination during pregnancy has been shown to decrease the risk of influenza and its complications among pregnant women and their infants up to 6 months old. To adequately assess the benefits and potential risks that are associated with the use of influenza vaccine during pregnancy, it is necessary to examine the influenza-associated complications that occur among pregnant women and their children. Pregnant women have been shown to be at increased risk for morbidity and death with influenza illness during seasonal epidemics and pandemics. Newborn infants born to mothers with influenza during pregnancy, especially mothers with severe illness, are at increased risk of adverse outcomes, such as preterm birth and low birthweight. Infants <6 months old who experience influenza virus infection have the highest rates of hospitalization and death of all children. Here we review the risks for influenza-associated complications among pregnant women and infants <6 months old.

Possible roles of proinflammatory and chemoattractive cytokines produced by human fetal membrane cells in the pathology of adverse pregnancy outcomes associated with influenza virus infection

Pregnant women are at an increased risk of influenza-associated adverse outcomes, such as premature delivery, based on data from the latest pandemic with a novel influenza A (H1N1) virus in 2009-2010. It has been suggested that the transplacental transmission of influenza viruses is rarely detected in humans. A series of our study has demonstrated that influenza virus infection induced apoptosis in primary cultured human fetal membrane chorion cells, from which a factor with monocyte differentiation-inducing (MDI) activity was secreted. Proinflammatory cytokines, such as interleukin (IL)-6, tumor necrosis factor (TNF)-α, and interferon (IFN)-β, were identified as a member of the MDI factor. Influenza virus infection induced the mRNA expression of not only the proinflammatory cytokines but also chemoattractive cytokines, such as monocyte chemoattractant protein (MCP)-1, regulated on activation, normal T-cell expressed and secreted (RANTES), macrophage inflammatory protein (MIP)-1β, IL-8, growth-regulated oncogene (GRO)-α, GRO-β, epithelial cell-derived neutrophil-activating protein (ENA)-78, and interferon inducible protein (IP)-10 in cultured chorion cells. These cytokines are postulated to associate with human parturition. This paper, therefore, reviews (1) lessons from pandemic H1N1 2009 in pregnancy, (2) production of proinflammatory and chemoattractive cytokines by human fetal membranes and their functions in gestational tissues, and (3) possible roles of cytokines produced by human fetal membranes in the pathology of adverse pregnancy outcomes associated with influenza virus infection.