Birth Outcomes Among People with Hepatitis C in Pregnancy - Three U.S. States, 2018-2021

INTRODUCTION

There are limited and conflicting data regarding the impact of hepatitis C in pregnancy on adverse birth outcomes.

METHODS

Using the Surveillance for Emerging Threats to Pregnant People and Infants Network (SET-NET), a large surveillance cohort, we describe birth outcomes among a cohort of people with HCV in pregnancy in total and by reported substance use.

RESULTS

Among 1418 infants, 89% were born to people with reported substance use during pregnancy. The proportion born preterm was 20%, 13% were small-for-gestational age and 34% of term infants required intensive care.

CONCLUSIONS

Assessments of recent changes to recommendations for HCV screening in pregnancy should evaluate the impact on maternal access to care for both HCV treatment as well as comorbidities such as substance use disorder which may contribute to adverse birth outcomes.

Use of an Additional Updated 2023-2024 COVID-19 Vaccine Dose for Adults Aged ≥65 Years: Recommendations of the Advisory Committee on Immunization Practices - United States, 2024

COVID-19 remains an important public health threat, despite overall decreases in COVID-19-related severe disease since the start of the COVID-19 pandemic. COVID-19-associated hospitalization rates remain higher among adults aged ≥65 years relative to rates in younger adults, adolescents, and children; during October 2023-January 2024, 67% of all COVID-19-associated hospitalizations were among persons aged ≥65 years. On September 12, 2023, CDC's Advisory Committee on Immunization Practices (ACIP) recommended updated (2023-2024 Formula) COVID-19 vaccination with a monovalent XBB.1.5-derived vaccine for all persons aged ≥6 months to protect against severe COVID-19-associated illness and death. Because SARS-CoV-2 continues to circulate throughout the year, and because of the increased risk for COVID-19-related severe illness in persons aged ≥65 years, the protection afforded by updated vaccines against JN.1 and other currently circulating variants, and the expected waning of vaccine-conferred protection against disease, on February 28, 2024, ACIP recommended all persons aged ≥65 years receive 1 additional dose of the updated (2023-2024 Formula) COVID-19 vaccine. Implementation of these recommendations is expected to enhance immunity that might have waned and decrease the risk for severe COVID-19-associated outcomes, including death, among persons aged ≥65 years.

CDC's New Hepatitis C Virus Testing Recommendations for Perinatally Exposed Infants and Children: A Step Towards Hepatitis C Elimination

New U.S. Centers for Disease Control and Prevention (CDC) guidelines for hepatitis C virus (HCV) testing of perinatally exposed infants and children released in 2023 recommend a nucleic acid test (NAT) for detection of HCV ribonucleic acid (i.e., NAT for HCV RNA) at 2-6 months of age to facilitate early identification and linkage to care for children with perinatally acquired HCV infection. Untreated hepatitis C can lead to cirrhosis, liver cancer, and premature death and is caused by HCV, a blood-borne virus transmitted most often among adults through injection drug use in the United States. Perinatal exposure from a birth parent with HCV infection is the most frequent mode of HCV transmission among infants and children. New HCV infections have been increasing since 2010, with the highest rates of infection among people aged 20-39 years, leading to an increasing prevalence of HCV infection during pregnancy. In 2020, the CDC recommended one-time HCV screening for all adults aged 18 years and older and for all pregnant persons during each pregnancy. Detecting HCV infection during pregnancy is key for the identification of pregnant persons, linkage to care for postpartum treatment, and identification of infants with perinatal exposure for HCV testing. It was previously recommended that children who were exposed to HCV during pregnancy receive an antibody to HCV (anti-HCV) test at 18 months of age; however, most children were lost to follow-up before testing occurred, leaving children with perinatal infection undiagnosed. The new strategy of testing perinatally exposed children at age 2-6 months was found to be cost-effective in increasing the identification of infants who might develop chronic hepatitis C. This report describes the current perinatal HCV testing recommendations and how they advance national hepatitis C elimination efforts by improving the health of pregnant and postpartum people and their children.

Frequency of Children Diagnosed with Perinatal Hepatitis C, United States, 2018-2020

We describe hepatitis C testing of 47 (2%) of 2,266 children diagnosed with perinatal hepatitis C who were exposed during 2018-2020 in 7 jurisdictions in the United States. Expected frequency of perinatal transmission is 5.8%, indicating only one third of the cases in this cohort were reported to public health authorities.

CDC Recommendations for Hepatitis C Testing Among Perinatally Exposed Infants and Children - United States, 2023

The elimination of hepatitis C is a national priority (https://www.hhs.gov/sites/default/files/Viral-Hepatitis-National-Strategic-Plan-2021-2025.pdf). During 2010-2021, hepatitis C virus (HCV) acute and chronic infections (hereinafter referred to as HCV infections) increased in the United States, consequences of which include cirrhosis, liver cancer, and death. Rates of acute infections more than tripled among reproductive-aged persons during this time (from 0.8 to 2.5 per 100,000 population among persons aged 20-29 years and from 0.6 to 3.5 among persons aged 30-39 years). Because acute HCV infection can lead to chronic infection, this has resulted in increasing rates of HCV infections during pregnancy. Approximately 6%-7% of perinatally exposed (i.e., exposed during pregnancy or delivery) infants and children will acquire HCV infection. Curative direct-acting antiviral therapy is approved by the Food and Drug Administration for persons aged ≥3 years. However, many perinatally infected children are not tested or linked to care. In 2020, because of continued increases in HCV infections in the United States, CDC released universal screening recommendations for adults, which included recommendations for screening for pregnant persons during each pregnancy (Schillie S, Wester C, Osborne M, Wesolowski L, Ryerson AB. CDC recommendations for hepatitis C screening among adults-United States, 2020. MMWR Recomm Rep 2020;69[No. RR-2]:1-17). This report introduces four new CDC recommendations: 1) HCV testing of all perinatally exposed infants with a nucleic acid test (NAT) for detection of HCV RNA at age 2-6 months; 2) consultation with a health care provider with expertise in pediatric hepatitis C management for all infants and children with detectable HCV RNA; 3) perinatally exposed infants and children with an undetectable HCV RNA result at or after age 2 months do not require further follow-up unless clinically warranted; and 4) a NAT for HCV RNA is recommended for perinatally exposed infants and children aged 7-17 months who previously have not been tested, and a hepatitis C virus antibody (anti-HCV) test followed by a reflex NAT for HCV RNA (when anti-HCV is reactive) is recommended for perinatally exposed children aged ≥18 months who previously have not been tested. Proper identification of perinatally infected children, referral to care, and curative treatment are critical to achieving the goal of hepatitis C elimination.

Recommendations for Prevention and Control of Influenza in Children, 2023-2024

This statement updates the recommendations of the American Academy of Pediatrics for the routine use of influenza vaccine and antiviral medications in the prevention and treatment of influenza in children during the 2023-2024 influenza season. A detailed review of the evidence supporting these recommendations is published in the accompanying technical report (www.pediatrics.org/cgi/doi/10.1542/peds.2023-063773). The American Academy of Pediatrics recommends annual influenza vaccination of all children without medical contraindications starting at 6 months of age. Children are at risk for hospitalization and death from influenza. Influenza vaccination is an important strategy for protecting children and the broader community, as well as reducing the overall burden of respiratory illnesses when other viruses are cocirculating. Any licensed influenza vaccine appropriate for age and health status can be administered, ideally as soon as possible in the season, without preference for one product or formulation over another. Antiviral treatment of influenza is recommended for children with suspected (eg, influenza-like illness [fever with either cough or sore throat]) or confirmed influenza who are hospitalized, have severe or progressive disease, or have underlying conditions that increase their risk of complications of influenza, regardless of duration of illness. Antiviral treatment should be initiated as soon as possible. Antiviral treatment may be considered in the outpatient setting for symptomatic children with suspected or confirmed influenza disease who are not at high risk for influenza complications, if treatment can be initiated within 48 hours of illness onset. Antiviral treatment may also be considered for children with suspected or confirmed influenza disease whose siblings or household contacts either are younger than 6 months or have a high-risk condition that predisposes them to complications of influenza. Antiviral chemoprophylaxis is recommended for the prevention of influenza virus infection as an adjunct to vaccination in certain individuals, especially exposed children who are at high risk for influenza complications but have not yet been immunized or those who are not expected to mount an effective immune response.

Recommendations for Prevention and Control of Influenza in Children, 2023-2024

This technical report accompanies the recommendations of the American Academy of Pediatrics for the routine use of influenza vaccine and antiviral medications in the prevention and treatment of influenza in children during the 2023-2024 season. The rationale for the American Academy of Pediatrics recommendation for annual influenza vaccination of all children without medical contraindications starting at 6 months of age is provided. Influenza vaccination is an important strategy for protecting children and the broader community against influenza. This technical report summarizes recent influenza seasons, morbidity and mortality in children, vaccine effectiveness, and vaccination coverage, and provides detailed guidance on vaccine storage, administration, and implementation. The report also provides a brief background on inactivated and live-attenuated influenza vaccines, available vaccines this season, vaccination during pregnancy and breastfeeding, diagnostic testing for influenza, and antiviral medications for treatment and chemoprophylaxis. Strategies to promote vaccine uptake are emphasized.

Cost-Effectiveness of Strategies to Identify Children with Perinatally Acquired Hepatitis C Infection

OBJECTIVE

To determine the optimal testing strategy to identify children with perinatally acquired hepatitis C virus (HCV) infection.

STUDY DESIGN

We used a decision-tree framework with a Markov disease progression model to conduct an economic analysis of 4 strategies, based on combinations of type and timing of test: anti-HCV with reflex to HCV RNA at 18 months among children known to be perinatally exposed (ie, baseline comparison strategy); HCV RNA testing at 2-6 months among infants known to be perinatally exposed (test strategy 1); universal anti-HCV with reflex to HCV RNA at 18 months among all children (test strategy 2); and universal HCV RNA testing at 2-6 months among all infants (test strategy 3). We estimated total cost, quality-adjusted life years, and disease sequalae for each strategy.

RESULTS

Each of the 3 alternative testing strategies resulted in an increased number of children tested and improved health outcomes. HCV RNA testing at 2-6 months (test strategy 1) was cost-saving and resulted in a population-level difference in cost of $469 671. The 2 universal testing strategies resulted in an increase in quality-adjusted life years and an increase in total costs.

CONCLUSIONS

Testing of perinatally exposed infants at age 2-6 months with a single HCV RNA test will reduce costs and improve health outcomes, preventing morbidity and mortality associated with complications from perinatal HCV infections.

Progress and Unfinished Business: Hepatitis B in the United States, 1980-2019

During 1990-2019, universal infant and childhood vaccination for hepatitis B resulted in a 99% decline in reported cases of acute hepatitis B among children, adolescents, and young adults aged <19 years in the United States; however, during 2010-2019, cases of acute hepatitis B plateaued or increased among adults aged ≥40 years. We conducted a topical review of surveillance strategies that will be critical to support the elimination of hepatitis B as a public health threat in the United States. In 2019, notifiable disease surveillance for acute hepatitis B showed continued transmission, especially among people who inject drugs and people with multiple sexual partners; rates were highest among people who were aged 30-59 years, non-Hispanic White, and living in rural areas. In contrast, newly reported cases of chronic hepatitis B (CHB) were highest among people who were aged 30-49 years, Asian or Pacific Islander, and living in urban areas. The National Health and Nutrition Examination Survey documented the highest CHB prevalence among non-US-born, non-Hispanic Asian people during 2013-2018; only one-third of people with CHB were aware of their infection. In the context of universal adult vaccination (2022) and screening (2023) recommendations for hepatitis B, better data are needed to support programmatic strategies to improve (1) vaccination rates among people with behaviors that put them at risk for transmission and (2) screening and linkage to care among non-US-born people. Surveillance for hepatitis B needs to be strengthened throughout the health care and public health systems.

Screening and Testing for Hepatitis B Virus Infection: CDC Recommendations - United States, 2023

Chronic hepatitis B virus (HBV) infection can lead to substantial morbidity and mortality. Although treatment is not considered curative, antiviral treatment, monitoring, and liver cancer surveillance can reduce morbidity and mortality. Effective vaccines to prevent hepatitis B are available. This report updates and expands CDC's previously published Recommendations for Identification and Public Health Management of Persons with Chronic Hepatitis B Virus Infection (MMWR Recomm Rep 2008;57[No. RR-8]) regarding screening for HBV infection in the United States. New recommendations include hepatitis B screening using three laboratory tests at least once during a lifetime for adults aged ≥18 years. The report also expands risk-based testing recommendations to include the following populations, activities, exposures, or conditions associated with increased risk for HBV infection: persons incarcerated or formerly incarcerated in a jail, prison, or other detention setting; persons with a history of sexually transmitted infections or multiple sex partners; and persons with a history of hepatitis C virus infection. In addition, to provide increased access to testing, anyone who requests HBV testing should receive it, regardless of disclosure of risk, because many persons might be reluctant to disclose stigmatizing risks.

Safety of measles, mumps, and rubella vaccine in adolescents and adults in the vaccine safety Datalink

Background

Measles, mumps, and rubella vaccine (MMR) is routinely administered to children; however, adolescents and adults may receive MMR for various reasons. Safety studies in adolescents and adults are limited. We report on safety of MMR in this age group in the Vaccine Safety Datalink.

Methods

We included adolescents (aged 9-17 years) and adults (aged ≥ 18 years) who received ≥ 1 dose of MMR from January 1, 2010-December 31, 2018. Pre-specified outcomes were identified by diagnosis codes. Clinically serious outcomes included anaphylaxis, encephalitis/myelitis, Guillain-Barré syndrome, immune thrombocytopenia, meningitis, and seizure. Non-serious outcomes were allergic reaction, arthropathy, fever, injection site reaction, lymphadenopathy, non-specific reaction, parotitis, rash, and syncope. All serious outcomes underwent medical record review. Outcome-specific incidence was calculated in pre-defined post-vaccination windows. A self-controlled risk interval design was used to determine the relative risk of each outcome in a risk window after vaccination compared to a more distal control window.

Results

During the study period, 276,327 MMR doses were administered to adolescents and adults. Mean age of vaccinees was 34.8 years; 65.8 % were female; 53.2 % of doses were administered simultaneously with ≥ 1 other vaccine. Serious outcomes were rare, with incidence ≤ 6 per 100,000 doses for each outcome assessed, and none had a significant elevation in incidence during the risk window compared to the control window. Incidence of non-serious outcomes per 100,000 doses ranged from 3.4 for parotitis to 263.0 for arthropathy. Other common outcomes included injection site reaction and rash (157.0 and 112.9 per 100,000 doses, respectively). Significantly more outcomes were observed during the risk window compared to the control window for all non-serious outcomes except parotitis. Some variability was observed by sex and age group.

Conclusion

Serious outcomes after MMR are rare in adolescents and adults, but vaccinees should be counseled regarding anticipated local and systemic non-serious adverse events.

Timing of Positive Hepatitis C Virus Test Results During and 1 Year Before Pregnancy

The incidence of hepatitis C virus (HCV) infection in reproductive-aged adults quadrupled during the past decade. Hepatitis C can progress to advanced liver disease and be transmitted perinatally. Highly effective curative hepatitis C treatment is available but is not recommended in pregnancy. Using the Surveillance for Emerging Threats to Mothers and Babies Network, we describe timing of positive RNA testing among pregnant people with HCV (HCV RNA detected during or within one year prior to pregnancy). Four US jurisdictions reported 1161 pregnancies during 2018-2021 among people with hepatitis C: 75.9% were multiparous; and 21.4% had their first peri-pregnancy HCV RNA detected prior to pregnancy, indicating potential missed treatment opportunities to improve maternal health and prevent perinatal transmission.

Kawasaki Disease Following the 13-valent Pneumococcal Conjugate Vaccine and Rotavirus Vaccines

BACKGROUND

Temporal associations between Kawasaki disease (KD) and childhood vaccines have been reported. Limited data on KD following 13-valent pneumococcal conjugate (PCV13) and rotavirus vaccines are available.

METHODS

We conducted a self-controlled risk interval study using Vaccine Safety Datalink electronic health record data to investigate the risk of KD following PCV13 and rotavirus vaccines in children <2 years of age who were born from 2006 to 2017. All hospitalized KD cases identified by International Classification of Diseases diagnosis codes that fell within predefined risk (days 1-28 postvaccination) and control (days 29-56 for doses 1 and 2, and days 43-70 for doses 3 and 4) intervals were confirmed by manual chart review.

RESULTS

During the study period, 655 cases of KD were identified by International Classification of Diseases codes. Of these, 97 chart-confirmed cases were within risk or control intervals. In analyses, the age-adjusted relative risk for KD following any dose of PCV13 was 0.75 (95% confidence interval, 0.47-1.21). Similarly, the age-adjusted relative risk for KD following any dose of rotavirus vaccine was 0.66 (95% CI, 0.40-1.09). Overall, there was no evidence of an elevated risk of KD following PCV13 or rotavirus vaccines by dose. In addition, no statistically significant temporal clustering of KD cases was identified during days 1 to 70 postvaccination.

CONCLUSIONS

PCV13 and rotavirus vaccination were not associated with an increased risk of KD in children <2 years of age. Our findings provide additional evidence for the overall safety of PCV13 and rotavirus vaccines.

Monitoring the safety of COVID-19 vaccines in pregnancy in the US

Pregnant persons are at increased risk of severe illness from COVID-19. The first COVID-19 vaccines in the U.S. were authorized for emergency use in December 2020 and pregnant persons were eligible and could get vaccinated despite scarce safety data in this population. To monitor the safety of COVID-19 vaccination during pregnancy, four surveillance systems are used by the Centers for Disease Control and Prevention (CDC). The Vaccine Adverse Event Reporting System is a national, passive system that captures reports of potential adverse events. V-safe is a novel, active system that uses text messaging and web-based surveys to provide health check-ins after vaccination; and enrolls eligible v-safe participants in the v-safe pregnancy registry. The Vaccine Safety Datalink is a collaboration between the CDC and nine integrated health care organizations which performs near-real time surveillance and traditional epidemiologic studies on pregnant vaccine recipients. The CDC is committed to timely and comprehensive monitoring of COVID-19 vaccine safety in pregnancy.

Measles in the 21st Century: Progress Toward Achieving and Sustaining Elimination

The global measles vaccination program has been extraordinarily successful in reducing measles-related disease and deaths worldwide. Eradication of measles is feasible because of several key attributes, including humans as the only reservoir for the virus, broad access to diagnostic tools that can rapidly detect measles-infectious persons, and availability of highly safe and effective measles-containing vaccines (MCVs). All 6 World Health Organization (WHO) regions have established measles elimination goals. Globally, during 2000–2018, measles incidence decreased by 66% (from 145 to 49 cases per million population) and deaths decreased by 73% (from 535 600 to 142 300), drastically reducing global disease burden. Routine immunization with MCV has been the cornerstone for the control and prevention of measles. Two doses of MCV are 97% effective in preventing measles, qualifying MCV as one of the most effective vaccines ever developed. Mild adverse events occur in <20% of recipients and serious adverse events are extremely rare. The economic benefits of measles vaccination are highlighted by an overall return on investment of 58 times the cost of the vaccine, supply chains, and vaccination. Because measles is one of the most contagious human diseases, maintenance of high (≥95%) 2-dose MCV coverage is crucial for controlling the spread of measles and successfully reaching measles elimination; however, the plateauing of global MCV coverage for nearly a decade and the global measles resurgence during 2018–2019 demonstrate that much work remains. Global commitments to increase community access to and demand for immunizations, strengthen national and regional partnerships for building public health infrastructure, and implement innovations that can overcome access barriers and enhance vaccine confidence, are essential to achieve a world free of measles.

Using maternal and neonatal data collection systems for coronavirus disease 2019 (COVID-19) vaccines active safety surveillance in low- and middle-income countries: an international modified Delphi study

Background: Given that pregnant women are now included among those for receipt coronavirus disease 2019 (COVID-19) vaccines, it is important to ensure that information systems can be used (or available) for active safety surveillance, especially in low- and middle-income countries (LMICs). The aim of this study was to build consensus about the use of existing maternal and neonatal data collection systems in LMICs for COVID-19 vaccines active safety surveillance, a basic set of variables, and the suitability and feasibility of including pregnant women and LMIC research networks in COVID-19 vaccines pre-licensure activities.  Methods: A three-stage modified Delphi study was conducted over three months in 2020. An international multidisciplinary panel of 16 experts participated. Ratings distributions and consensus were assessed, and ratings’ rationale was analyzed.  Results: The panel recommended using maternal and neonatal data collection systems for active safety surveillance in LMICs (median 9; disagreement index [DI] -0.92), but there was no consensus (median 6; DI 1.79) on the feasibility of adapting these systems. A basic set of 14 maternal, neonatal, and vaccination-related variables. Out of 16 experts, 11 supported a basic set of 14 maternal, neonatal, and vaccination-related variables for active safety surveillance. Seven experts agreed on a broader set of 26 variables.The inclusion of pregnant women for COVID-19 vaccines research (median 8; DI -0.61) was found appropriate, although there was uncertainty on its feasibility in terms of decision-makers’ acceptability (median 7; DI 10.00) and regulatory requirements (median 6; DI 0.51). There was no consensus (median 6; DI 2.35) on the feasibility of including research networks in LMICs for conducting clinical trials amongst pregnant women. Conclusions: Although there was some uncertainty regarding feasibility, experts recommended using maternal and neonatal data collection systems and agreed on a common set of variables for COVID-19 vaccines active safety surveillance in LMICs.

Preliminary Findings of mRNA Covid-19 Vaccine Safety in Pregnant Persons

BACKGROUND

Many pregnant persons in the United States are receiving messenger RNA (mRNA) coronavirus disease 2019 (Covid-19) vaccines, but data are limited on their safety in pregnancy.

METHODS

From December 14, 2020, to February 28, 2021, we used data from the "v-safe after vaccination health checker" surveillance system, the v-safe pregnancy registry, and the Vaccine Adverse Event Reporting System (VAERS) to characterize the initial safety of mRNA Covid-19 vaccines in pregnant persons.

RESULTS

A total of 35,691 v-safe participants 16 to 54 years of age identified as pregnant. Injection-site pain was reported more frequently among pregnant persons than among nonpregnant women, whereas headache, myalgia, chills, and fever were reported less frequently. Among 3958 participants enrolled in the v-safe pregnancy registry, 827 had a completed pregnancy, of which 115 (13.9%) resulted in a pregnancy loss and 712 (86.1%) resulted in a live birth (mostly among participants with vaccination in the third trimester). Adverse neonatal outcomes included preterm birth (in 9.4%) and small size for gestational age (in 3.2%); no neonatal deaths were reported. Although not directly comparable, calculated proportions of adverse pregnancy and neonatal outcomes in persons vaccinated against Covid-19 who had a completed pregnancy were similar to incidences reported in studies involving pregnant women that were conducted before the Covid-19 pandemic. Among 221 pregnancy-related adverse events reported to the VAERS, the most frequently reported event was spontaneous abortion (46 cases).

CONCLUSIONS

Preliminary findings did not show obvious safety signals among pregnant persons who received mRNA Covid-19 vaccines. However, more longitudinal follow-up, including follow-up of large numbers of women vaccinated earlier in pregnancy, is necessary to inform maternal, pregnancy, and infant outcomes.

Vaccine Safety Datalink infrastructure enhancements for evaluating the safety of maternal vaccination

BACKGROUND

Identifying pregnancy episodes and accurately estimating their beginning and end dates are imperative for observational maternal vaccine safety studies using electronic health record (EHR) data.

METHODS

We modified the Vaccine Safety Datalink (VSD) Pregnancy Episode Algorithm (PEA) to include both the International Classification of Disease, ninth revision (ICD-9 system) and ICD-10 diagnosis codes, incorporated additional gestational age data, and validated this enhanced algorithm with manual medical record review. We also developed the new Dynamic Pregnancy Algorithm (DPA) to identify pregnancy episodes in real time.

RESULTS

Around 75% of the pregnancy episodes identified by the enhanced VSD PEA were live births, 12% were spontaneous abortions (SABs), 10% were induced abortions (IABs), and 0.4% were stillbirths (SBs). Gestational age was identified for 99% of live births, 89% of SBs, 69% of SABs, and 42% of IABs. Agreement between the PEA-assigned and abstractor-identified pregnancy outcome and outcome date was 100% for live births, but was lower for pregnancy losses. When gestational age was available in the medical record, the agreement was higher for live births (97%), but lower for pregnancy losses (75%). The DPA demonstrated strong concordance with the PEA and identified pregnancy episodes ⩾6 months prior to the outcome date for 89% of live births.

CONCLUSION

The enhanced VSD PEA is a useful tool for identifying pregnancy episodes in EHR databases. The DPA improves the timeliness of pregnancy identification and can be used for near real-time maternal vaccine safety studies.

PLAIN LANGUAGE SUMMARY

Improving identification of pregnancies in the Vaccine Safety Datalink electronic medical record databases to allow for better and faster monitoring of vaccination safety during pregnancy Introduction: It is important to monitor of the safety of vaccines after they have been approved and licensed by the Food and Drug Administration, especially among women vaccinated during pregnancy. The Vaccine Safety Datalink (VSD) monitors vaccine safety through observational studies within large databases of electronic medical records. Since 2012, VSD researchers have used an algorithm called the Pregnancy Episode Algorithm (PEA) to identify the medical records of women who have been pregnant. Researchers then use these medical records to study whether receiving a particular vaccine is linked to any negative outcomes for the woman or her child.Methods: The goal of this study was to update and enhance the PEA to include the full set of medical record diagnostic codes [both from the older International Classification of Disease, ninth revision (ICD-9 system) and the newer ICD-10 system] and to incorporate additional sources of data about gestational age. To ensure the validity of the PEA following these enhancements, we manually reviewed medical records and compared the results with the algorithm. We also developed a new algorithm, the Dynamic Pregnancy Algorithm (DPA), to identify women earlier in pregnancy, allowing us to conduct more timely vaccine safety assessments.Results: The new version of the PEA identified 2,485,410 pregnancies in the VSD database. The enhanced algorithm more precisely estimated the beginning of pregnancies, especially those that did not result in live births, due to the new sources of gestational age data.Conclusion: Our new algorithm, the DPA, was successful at identifying pregnancies earlier in gestation than the PEA. The enhanced PEA and the new DPA will allow us to better evaluate the safety of current and future vaccinations administered during or around the time of pregnancy.

Adverse Outcomes in Pregnant Women Hospitalized With Respiratory Syncytial Virus Infection: A Case Series

We identified 10 women hospitalized with respiratory syncytial virus infection during pregnancy. Diagnoses included pneumonia/atelectasis (5), respiratory failure (2), and sepsis (2). Six had obstetrical complications during hospitalization, including 1 induced preterm birth. One required intensive care unit admission and mechanical ventilation. Four infants had complications at birth.

Association of Inadvertent 9-Valent Human Papillomavirus Vaccine in Pregnancy With Spontaneous Abortion and Adverse Birth Outcomes

IMPORTANCE

The 9-valent human papillomavirus (9vHPV) vaccine is recommended for individuals through age 26 years and may be administered to women up to age 45 years. Data on 9vHPV vaccine exposures during pregnancy are limited.

OBJECTIVE

To evaluate the associations between 9vHPV vaccine exposures during pregnancy or peripregnancy and selected pregnancy and birth outcomes (spontaneous abortion [SAB], preterm birth, small-for-gestational age [SGA] birth, and major structural birth defect).

DESIGN, SETTING, AND PARTICIPANTS

This cohort study analyzed data from 7 participating health systems in the Vaccine Safety Datalink. The cohort comprised pregnancies among girls and women aged 12 to 28 years that ended between October 26, 2015, and November 15, 2018. Singleton pregnancies that ended in a live birth, stillbirth, or SAB were included.

EXPOSURES

Vaccine exposure windows were distal (9vHPV or 4vHPV vaccine administered from 22 to 16 weeks before last menstrual period [LMP]), peripregnancy (9vHPV vaccine administered from 42 days before LMP until LMP), and during pregnancy (9vHPV vaccine administered from LMP to 19 completed weeks' gestation). Primary comparisons were (1) girls and women with 9vHPV vaccine exposures during pregnancy vs those with 4vHPV or 9vHPV distal vaccine exposures, (2) girls and women with vaccine exposures peripregnancy vs those with 4vHPV or 9vHPV distal vaccine exposures, and (3) girls and women with 9vHPV vaccine exposures during pregnancy or peripregnancy vs those with 4vHPV or 9vHPV distal vaccine exposure.

MAIN OUTCOMES AND MEASURES

Spontaneous abortions were confirmed based on medical record review and adjudication. Preterm and SGA births were identified from electronic health record and birth data. Major structural birth defects were based on diagnostic codes using a validated algorithm. Inverse probability weighting was used to balance the covariates. Time-dependent covariate Cox proportional hazards regression models and Poisson regression were used to estimate the associations between 9vHPV vaccine exposures and pregnancy and birth outcomes.

RESULTS

The final cohort included 1493 pregnancies among girls and women with a mean (SD) maternal age of 23.9 (2.9) years. Of these pregnancies, 445 (29.8%) had exposures to the 9vHPV vaccine during pregnancy, 496 (33.2%) had exposures to the 9vHPV vaccine peripregnancy, and 552 (37.0%) had 4vHPV or 9vHPV distal vaccine exposures. The 9vHPV vaccine administered during pregnancy was not associated with increased risk for SAB (hazard ratio, 1.12; 95% CI, 0.66-1.93) compared with distal vaccine exposures. Findings were similar for 9vHPV vaccine exposures peripregnancy (relative risk [RR], 0.72; 95% CI, 0.42-1.24). Among live births (n = 1409), 9vHPV vaccine exposures during pregnancy were not associated with increased risks for preterm birth (RR, 0.73; 95% CI, 0.44-1.20) or SGA birth (RR, 1.31; 95% CI, 0.78-2.20). Results were similar regarding the association between 9vHPV vaccine exposures peripregnancy and preterm birth (RR, 0.72; 95% CI, 0.45-1.17) and SGA birth (RR, 1.10; 95% CI, 0.65-1.88). Birth defects were rare in all exposure groups, occurring in about 1% of live births with available infant data.

CONCLUSIONS AND RELEVANCE

This study found that 9vHPV vaccine exposures during or around the time of pregnancy were uncommon and not associated with SABs or selected adverse birth outcomes. These findings can inform counseling for inadvertent 9vHPV vaccine exposures.

2763. Uptake and Safety of Measles-Mumps-Rubella (MMR) Vaccine in Adolescents and Adults in the Vaccine Safety Datalink

Background

MMR vaccine is given routinely to young children but may be given at other ages. We described MMR use in adolescent and adult populations in the Vaccine Safety Datalink (VSD) and estimated the incidence of medically-attended outcomes after MMR to inform future studies estimating vaccine-associated risk.

Methods

The study population included adolescents (9–17 years) and adults (≥18 years) in VSD who received at least one MMR vaccine from 2010 through 2016. Outcomes were pre-specified based on previous vaccine safety studies and categorized as clinically serious (anaphylaxis, encephalitis/myelitis, GBS, meningitis, seizure) or non-serious (allergic reaction, arthropathy, fever, injection site reaction, lymphadenopathy, nonspecific reaction, parotitis, rash, syncope). Outcomes were identified by searching for ICD-9 and ICD-10 diagnosis codes in post-vaccination exposure windows. Medical records were reviewed for all serious outcomes to verify incident diagnoses. Incidence and 95% confidence intervals were calculated for validated serious and all non-serious outcomes.

Results

146,503 adolescents and adults received 162,992 MMR vaccines during the study period. The mean age at vaccination was 33.7 years, 65% were female, and 53% received at least one other vaccine simultaneously. Demographic and vaccination characteristics varied across age groups (Table 1). The analysis of post-vaccination outcomes included 162,053 MMR vaccinations. The incidence of validated serious outcomes was low, ranging from 0 to 6.8 per 100,000 vaccinations. Only one serious outcome (anaphylaxis) was noted to be vaccine-associated in the medical record. Incidence of clinically non-serious outcomes varied from 0.4 to 56.0 per 10,000 vaccinations. Injection site reactions were more common among adolescents (118.1 per 10,000 vaccinations), who also had a higher frequency of simultaneous vaccination (80%).

Conclusion

Clinically serious outcomes were rare following MMR vaccination. Rates of clinically non-serious outcomes varied but were similar to or lower than previous reports in children. This descriptive analysis did not evaluate the association between MMR and adverse events. Future analysis with an appropriate comparison group is needed for risk estimation.

Disclosures

All authors: No reported disclosures.

Uptake and safety of hepatitis A vaccination during pregnancy: A Vaccine Safety Datalink study

INTRODUCTION

Infection with hepatitis A virus (HAV) during pregnancy, although uncommon, is associated with gestational complications and pre-term labor. Hepatitis A vaccine (HepA) is recommended for anyone at increased risk for contracting hepatitis A, including women at risk who are also pregnant. Limited data are available on the safety of maternal HepA vaccination.

OBJECTIVES

Assess the frequency of maternal HepA receipt and evaluate the potential association between maternal vaccination and pre-specified maternal and infant safety outcomes.

METHODS

A retrospective cohort of pregnancies in the Vaccine Safety Datalink (VSD) resulting in live births from 2004 through 2015 was included. Pregnancies with HepA exposure were compared to those with other vaccine exposures, and to those with no vaccine exposures. Risk factors for contracting hepatitis A were identified up to one-year prior to or during the pregnancy using ICD-9 codes. Maternal and fetal adverse events were evaluated according to maternal HepA exposure status. Adjusted odds ratio (OR) were used to describe the association.

RESULTS

Among 666,233 pregnancies in the study period, HepA was administered at a rate of 1.7 per 1000 (n = 1140), most commonly within the first six weeks of pregnancy. Less than 3% of those exposed to HepA during pregnancy had an ICD-confirmed risk factor. There were no significant associations between HepA exposure during pregnancy and gestational hypertension, gestational diabetes, pre-eclampsia/eclampsia, cesarean delivery, pre-term delivery, and low birthweight. There was a statistically significant association between HepA exposure during pregnancy and small-for-gestational age (SGA) infants (aOR 1.32, [95% CI 1.09, 1.60], p = 0.004).

CONCLUSIONS

The rate of maternal HepA vaccination was low and rarely due to documented risk factors for vaccination. HepA vaccination during pregnancy was not associated with an increased risk for a range of adverse events examined among pregnancies resulting in live births, but an identified association between maternal HepA and SGA infant outcomes, while likely due to unmeasured confounding, warrants further exploration.

Estimation of the Incidence of Guillain-Barré Syndrome During Pregnancy in the United States

Guillain-Barré syndrome (GBS) is an adverse event of interest after vaccination, yet few data are available for background rates during pregnancy. We confirmed 2 cases of incident GBS and estimated an incidence of 2.8 confirmed GBS cases per million person-years (95% confidence interval, 0.5-9.3), indicating rare occurrence. Our findings will help inform safety assessments of Zika vaccines in pregnant populations.

The role of the sonic hedgehog signalling pathway in patients with midline defects and congenital hypopituitarism

INTRODUCTION

The Gli family of zinc finger (GLI) transcription factors mediates the sonic hedgehog signalling pathway (HH) essential for CNS, early pituitary and ventral forebrain development in mice. Human mutations in this pathway have been described in patients with holoprosencephaly (HPE), isolated congenital hypopituitarism (CH) and cranial/midline facial abnormalities. Mutations in Sonic hedgehog (SHH) have been associated with HPE but not CH, despite murine studies indicating involvement in pituitary development.

OBJECTIVES/METHODS

We aimed to establish the role of the HH pathway in the aetiology of hypothalamo-pituitary disorders by screening our cohort of patients with midline defects and/or CH for mutations in SHH, GLI2, Shh brain enhancer 2 (SBE2) and growth-arrest specific 1 (GAS1).

RESULTS

Two variants and a deletion of GLI2 were identified in three patients. A novel variant at a highly conserved residue in the zinc finger DNA-binding domain, c.1552G > A [pE518K], was identified in a patient with growth hormone deficiency and low normal free T4. A nonsynonymous variant, c.2159G > A [p.R720H], was identified in a patient with a short neck, cleft palate and hypogonadotrophic hypogonadism. A 26·6 Mb deletion, 2q12·3-q21·3, encompassing GLI2 and 77 other genes, was identified in a patient with short stature and impaired growth. Human embryonic expression studies and molecular characterisation of the GLI2 mutant p.E518K support the potential pathogenicity of GLI2 mutations. No mutations were identified in GAS1 or SBE2. A novel SHH variant, c.1295T>A [p.I432N], was identified in two siblings with variable midline defects but normal pituitary function.

CONCLUSIONS

Our data suggest that mutations in SHH, GAS1 and SBE2 are not associated with hypopituitarism, although GLI2 is an important candidate for CH.