Spontaneous reports of primary ovarian insufficiency after vaccination: A review of the vaccine adverse event reporting system (VAERS).

BACKGROUND: Since 2012, reports of primary ovarian insufficiency (POI) temporally associated with receipt of human papillomavirus (HPV) vaccine have been published leading to questions about a potential causal association. A Vaccine Safety Datalink study did not find an increased risk for POI after vaccination. We reviewed the Vaccine Adverse Event Reporting System (VAERS) to describe POI reports. METHODS: We searched VAERS, a U.S. passive surveillance system, for domestic POI reports received from 01/01/1990 to 12/31/2017 after any vaccination. The search used both Medical Dictionary for Regulatory Activity Preferred Terms and a text-based search for POI and its symptoms. All reports were reviewed, and the American College of Obstetricians and Gynecologists (ACOG) guidelines for POI diagnosis were applied. Data mining for disproportionate reporting was conducted. RESULTS: Six hundred fifty-two reports met the search criteria and clinical review identified 19 POI reports. Most reports (n = 16) were received between 2013 and 2017. The median age at vaccination was 14.5 years (range 10-25 years) and the median interval between first dose of vaccination and reporting the event to VAERS was 43 months (range 4-132 months; mean 59.6 months). Four reports met ACOG diagnostic criteria; one with an underlying cause (47XXX chromosomal abnormality) reported. Eleven reports documented menstrual irregularity ≥ 3 months; 5 had ≥ 1 laboratory test result used to diagnose POI. Eighteen of 19 reports described receipt of HPV vaccine with or without other vaccines. Other vaccines reported were meningococcal conjugate vaccine, hepatitis A, varicella and tetanus toxoid, reduced diphtheria toxoid and acellular pertussis. Disproportionate reporting was found for three relevant coding terms after HPV vaccination. CONCLUSIONS: POI is rarely reported to VAERS. Most reports contained limited diagnostic information and were submitted after published cases of POI following HPV vaccination. Results of our review do not suggest a safety concern.

Is there any harm in administering extra-doses of vaccine to a person? Excess doses of vaccine reported to the Vaccine Adverse Event Reporting System (VAERS), 2007-2017.

BACKGROUND: The administration of an extra dose of a vaccine may occur due to a programmatic error (e.g., vaccination error) when there is need to provide one of the antigens of a combination vaccine not readily available as a single antigen, or when there is need to provide immunization in a person with uncertain vaccination histories (e.g., refugees). There is little data available on the safety of an extra dose of vaccine. OBJECTIVE: To assess for the presence of adverse events (AEs) most commonly reported following the administration of excess doses of vaccine in the Vaccine Adverse Event Reporting System (VAERS). METHODS: We searched VAERS for US reports where an excess dose of vaccine was administered to a person received from 1/1/2007 through 1/26/2018. We reviewed medical records for all serious reports and a random sample of non-serious reports. The most common AEs among reports of excess dose of vaccine administered were compared with the corresponding AEs for all vaccines reported to VAERS during the same period. RESULTS: Out of 366,815 total VAERS reports received, 5067 (1.4%) reported an excess dose of vaccine was administered; 3898 (76.9%) did not describe an adverse health event (AHE). The most common vaccines reported were trivalent inactivated influenza (15.4%), varicella (13.9%), hepatitis A (11.4%), and measles, mumps, rubella, varicella (11.1%). Among reports where only AHEs were reported, the most common were pyrexia (12.8%), injection site erythema (9.7%), injection site pain (8.9%), and headache (6.6%). The percentage of AHEs among these reports was comparable to all reports submitted to VAERS during the same study period. CONCLUSION: More than three-fourths of reports of an excess dose of vaccine did not describe an AHE. Among reports where an AHE event was reported, we did not observe any unexpected conditions or clustering of AEs.

Assessing the safety of hepatitis B vaccination during pregnancy in the Vaccine Adverse Event Reporting System (VAERS), 1990-2016.

BACKGROUND: The safety of hepatitis B vaccination during pregnancy has not been well studied. OBJECTIVE: We characterized adverse events (AEs) after hepatitis B vaccination of pregnant women reported to the Vaccine Adverse Event Reporting System (VAERS), a spontaneous reporting surveillance system. METHODS: We searched VAERS for AEs reports involving pregnant women who received hepatitis B vaccine from January 1, 1990-June 30, 2016. All reports and available medical records were reviewed by physicians. Observed AEs were compared to expected AEs and known rates of pregnancy outcomes to assess for any unexpected safety concern. RESULTS: We found 192 reports involving pregnant women following hepatitis B vaccination of which 110 (57.3%) described AEs; 12 (6.3%) were classified as serious; one newborn death was identified in a severely premature delivery, and there were no maternal deaths. Eighty-two (42.7%) reports did not describe any AEs. Among pregnancies for which gestational age was reported, most women were vaccinated during the first trimester, 86/115 (74.7%). Among reports describing an AE, the most common pregnancy-specific outcomes included spontaneous abortion in 23 reports, preterm delivery in 7 reports, and elective termination in 5 reports. The most common non-pregnancy specific outcomes were general disorders and administration site conditions, such as injection site and systemic reactions, in 21 reports. Among 22 reports describing an AE among infants born to women vaccinated during pregnancy, 5 described major birth defects each affecting different organ systems. CONCLUSION: Our analysis of VAERS reports involving hepatitis B vaccination during pregnancy did not identify any new or unexpected safety concerns.

Using Probabilistic Record Linkage of Structured and Unstructured Data to Identify Duplicate Cases in Spontaneous Adverse Event Reporting Systems.

INTRODUCTION: Duplicate case reports in spontaneous adverse event reporting systems pose a challenge for medical reviewers to efficiently perform individual and aggregate safety analyses. Duplicate cases can bias data mining by generating spurious signals of disproportional reporting of product-adverse event pairs. OBJECTIVE: We have developed a probabilistic record linkage algorithm for identifying duplicate cases in the US Vaccine Adverse Event Reporting System (VAERS) and the US Food and Drug Administration Adverse Event Reporting System (FAERS). METHODS: In addition to using structured field data, the algorithm incorporates the non-structured narrative text of adverse event reports by examining clinical and temporal information extracted by the Event-based Text-mining of Health Electronic Records system, a natural language processing tool. The final component of the algorithm is a novel duplicate confidence value that is calculated by a rule-based empirical approach that looks for similarities in a number of criteria between two case reports. RESULTS: For VAERS, the algorithm identified 77% of known duplicate pairs with a precision (or positive predictive value) of 95%. For FAERS, it identified 13% of known duplicate pairs with a precision of 100%. The textual information did not improve the algorithm's automated classification for VAERS or FAERS. The empirical duplicate confidence value increased performance on both VAERS and FAERS, mainly by reducing the occurrence of false-positives. CONCLUSIONS: The algorithm was shown to be effective at identifying pre-linked duplicate VAERS reports. The narrative text was not shown to be a key component in the automated detection evaluation; however, it is essential for supporting the semi-automated approach that is likely to be deployed at the Food and Drug Administration, where medical reviewers will perform some manual review of the most highly ranked reports identified by the algorithm.

Safety of influenza A (H1N1) 2009 live attenuated monovalent vaccine in pregnant women.

OBJECTIVE: To characterize maternal and infant outcomes for pregnant women who received live H1N1 influenza vaccine and had no reported adverse events. METHODS: We identified Vaccine Adverse Event Reporting System reports, which described receipt of live H1N1 vaccine during pregnancy without an indication of an adverse event at the time of the report during October 2009 to June 2010. We reviewed the initial reports and obtained pregnancy outcome and infant data through 6 months of age from medical records. We reviewed the numbers and characteristics of pregnancy complications and infant outcomes including major birth defects and medically important infant conditions. Rates of spontaneous abortion, preterm birth, and major birth defects and their 95% confidence intervals were calculated. RESULTS: The Vaccine Adverse Event Reporting System received 113 reports stating receipt of live H1N1 vaccine during pregnancy with no adverse events reported. We obtained follow-up maternal records on 95 of the 113 (84%) live H1N1 reports (40.2% were vaccinated in the first trimester) and found: 87 live births (two twin pregnancies) and no maternal deaths occurred. Number and rates of pregnancy-specific adverse events included: 10 (10.5%, 5.8-18.3) spontaneous abortions; four (4.7%, 1.8-11.4) preterm deliveries at 35-36 weeks of gestation; three (3.4%, 1.2-9.7) infants had one or more major birth defects noted at birth: one cleft palate, one cleft lip, and one microtia (underdeveloped or absent external ear). Seven neonates and infants were hospitalized for medically important conditions. One infant death occurred in a 2.5-month-old boy as a result of pertussis. CONCLUSION: Rates of spontaneous abortion, preterm birth, and major birth defects in pregnant women who received live H1N1 vaccine were similar to or lower than published background rates. No concerning patterns of medical conditions in infants were identified. LEVEL OF EVIDENCE: : III.

Adverse event reports after tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccines in pregnant women.

OBJECTIVE: We sought to characterize reports to the Vaccine Adverse Event Reporting System (VAERS) of pregnant women who received tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine (Tdap). STUDY DESIGN: We searched VAERS for reports of pregnant women who received Tdap from Jan. 1, 2005, through June 30, 2010. We conducted a clinical review of reports and available medical records. RESULTS: We identified 132 reports of Tdap administered to pregnant women; 55 (42%) described no adverse event (AE). No maternal or infant deaths were reported. The most frequent pregnancy-specific AE was spontaneous abortion in 22 (16.7%) reports. Injection site reactions were the most frequent non-pregnancy-specific AE found in 6 (4.5%) reports. One report with a major congenital anomaly (gastroschisis) was identified. CONCLUSION: During a time when Tdap was not routinely recommended in pregnancy, review of reports to VAERS in pregnant women after Tdap did not identify any concerning patterns in maternal, infant, or fetal outcomes.

Adverse events following administration to pregnant women of influenza A (H1N1) 2009 monovalent vaccine reported to the Vaccine Adverse Event Reporting System.

OBJECTIVE: The objective of the study was to evaluate and summarize reports to the Vaccine Adverse Event Reporting System (VAERS), a spontaneous reporting system, in pregnant women who received influenza A (H1N1) 2009 monovalent vaccine to assess for potential vaccine safety problems. STUDY DESIGN: We reviewed reports of adverse events (AEs) in pregnant women who received 2009-H1N1 vaccines from Oct. 1, 2009, through Feb. 28, 2010. RESULTS: VAERS received 294 reports of AEs in pregnant women who received 2009-H1N1 vaccine: 288 after inactivated and 6 after the live attenuated vaccines. Two maternal deaths were reported. Fifty-nine women (20.1%) were hospitalized. We verified 131 pregnancy-specific outcomes: 95 spontaneous abortions (<20 weeks); 18 stillbirths (≥20 weeks); 7 preterm deliveries (<37 weeks); 3 threatened abortions; 2 preterm labor; 2 preeclampsia; and 1 each of fetal hydronephrosis, fetal tachycardia, intrauterine growth retardation, and cleft lip. CONCLUSION: Review of reports to VAERS following H1N1 vaccination in pregnant women did not identify any concerning patterns of maternal or fetal outcomes.