Objectives: To quantify the incidence of adverse events given COVID-19 vaccination and COVID-19 diagnosis in women of reproductive age; to examine pregnancy as a potential risk modifier.
Methods: An exposure-matched cohort study of >1 million women, 11 December 2020-30 September 2022, United States. COVID-19 vaccination, COVID-19 diagnoses, and medically-attended adverse events - including immunologic, neurologic, cerebrovascular, thromboembolic, cardiovascular, respiratory, thrombocytopenic and coagulative events - were identified from inpatient and outpatient medical claims.
Although immunization during pregnancy can protect mothers and their infants from vaccine-preventable morbidity and mortality, vaccination rates are often poor. We systematically reviewed the literature from inception to July 4, 2023, for randomized and non-randomized quasi-experimental studies estimating the effects of interventions to increase vaccination during pregnancy. Of 9331 studies screened, 36 met inclusion criteria, including 18 demand-side interventions, 11 supply-side interventions, and seven multi-level (demand and supply-side) interventions.
View Article and Find Full Text PDFBackground And Objectives: COVID-19 vaccination is recommended during pregnancy; however, evidence on the prevalence of major structural birth defects born to people vaccinated early in pregnancy (≤20 weeks of gestation) is limited. We compared the prevalence of major structural birth defects by COVID-19 vaccination status and key strata: insurance provider, clinically diagnosed SARS-CoV-2 infection during pregnancy, and concomitant administration of other maternal vaccines. We also compared, head-to-head, the prevalence of birth defects by brand (Moderna mRNA-1273 vs Pfizer-BioNTech BNT162b2).
View Article and Find Full Text PDFWestern Pac Surveill Response J
May 2025
Objective: Mortality surveillance was established in the state of Victoria just before the COVID-19 pandemic. Here, we describe the establishment of this surveillance system, justify the modelling approach selected, and provide examples of how the interpretation of changes in mortality rates during the pandemic was influenced by the model chosen.
Methods: Registered deaths occurring in Victoria from 1 January 2015 to 31 December 2020 were sourced from the Victoria Death Index.
Pediatr Infect Dis J
February 2025
Real-world data can be used to evaluate the postlicensure safety of vaccines during pregnancy. However, these studies often require special design considerations to minimize bias. We offer 4 recommendations for maximizing the use of real-world data for vaccine safety evaluations during pregnancy, including the application of robust methodology, standardized outcome definitions, global collaboration and platforms for data sharing.
View Article and Find Full Text PDFClin Infect Dis
March 2025
Background: Pregnant people are at risk of severe coronavirus disease 2019 (COVID-19) and associated complications. While withholding treatment from pregnant patients is not recommended, little is known about the frequency of antiviral medication use during pregnancy.
Methods: Using Medicaid and commercial insurance databases, we constructed a national claims-based cohort study of pregnant, recently pregnant, and nonpregnant female patients 18-49 years old with an outpatient diagnosis of COVID-19 between 21 December 2021 and 30 September 2022.
To estimate maternal COVID-19, influenza, and pertussis vaccine uptake during pregnancy by insurance type and identify factors characterizing those vaccinated and unvaccinated. We conducted a US cohort study of pregnant individuals (for pregnancies ending December 11, 2020-September 30, 2022) using insurance claims data. We calculated vaccination probability using Kaplan-Meier methods and identified factors associated with vaccination through binomial regression with inverse probability weights.
View Article and Find Full Text PDFObjectives: To compare serological evidence of prior severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection with linked coronavirus disease 2019 (COVID-19) case notification data in Victoria, Australia, and to determine SARS-CoV-2 neutralisation activity based on prior infection and vaccination history.
Design, Setting, Participants: Four cross-sectional serological surveys were conducted between 30 June and 31 October 2022 (a period of Omicron BA.4/BA.
J Gastroenterol Hepatol
November 2024
Background And Aim: Pregnancy is a key setting for engagement in chronic hepatitis B (CHB) care, due to the implications for transmission to the infant and antenatal diagnosis representing an opportunity for ongoing follow-up. This study aimed to identify the coverage and predictors of clinical care for women with CHB during and after pregnancy in a population-level cohort.
Methods: Notified CHB cases in Victoria, Australia, were linked with hospitalizations, medical services, and prescribing data, covering the period 1991-2018.
Background: Highly effective hepatitis C therapies are available in Australia. However, people living with hepatitis C face various barriers to accessing care and treatment.
Aims: To identify gaps in the cascade of care for hepatitis C and generate estimates of the number living with untreated infection according to population group, using a representative longitudinal study population.
Background: The Coronavirus Disease 2019 (COVID-19) pandemic led to extensive vaccination campaigns worldwide, including in Australia. Immunity waning and the emergence of new viral variants pose challenges to the effectiveness of vaccines. Our study aimed to assess the relative effectiveness (rVE) of 3 and 4 compared with 2 doses of COVID-19 vaccine.
View Article and Find Full Text PDFLancet Reg Health West Pac
September 2023
Background: Understanding mortality burden associated with communicable diseases is key to informing resource allocation, disease prevention and control efforts, and evaluating public health interventions. We quantified excess mortality among people notified with communicable diseases in Victoria, Australia.
Methods: Cases of communicable disease notified in Victoria between 1 January 1991 and 31 December 2021 were linked to the death registry.
Background And Aim: This study aimed to assess utilization of health-care services in people with decompensated cirrhosis (DC) or hepatocellular carcinoma (HCC) and a "late diagnosis" of hepatitis B or hepatitis C.
Methods: Hepatitis B and C cases during 1997-2016 in Victoria, Australia, were linked with hospitalizations, deaths, liver cancer diagnoses, and medical services. A late diagnosis was defined as hepatitis B or hepatitis C notification occurring after, at the same time, or within 2 years preceding an HCC/DC diagnosis.
Background: Mother-to-child transmission (MTCT) of hepatitis B virus (HBV) remains one of the leading causes of transmission worldwide. An estimated 90 % of infants who are exposed to HBV and do not receive appropriate post exposure immunoprophylaxis will go on to develop chronic hepatitis B (CHB). In Australia, universal birth dose vaccination was adopted in 2000 and universal antenatal screening for hepatitis B was introduced in the 1990 s, however up to 10 % of women may have missed screening.
View Article and Find Full Text PDFAust J Prim Health
July 2023
Background: Standard care for pregnant women includes universal screening for hepatitis B, and administration of influenza and pertussis vaccination to women and hepatitis B infant vaccination. This study explored how perinatal services relating to the prevention of these vaccine-preventable diseases are delivered to women and their infants in Victoria, Australia.
Methods: Two online surveys investigated service delivery for the prevention of influenza, pertussis and hepatitis B to identify barriers to optimal care during January-June 2021; (1) The Birthing Hospitals Survey captured facility-level information about service delivery for influenza and pertussis vaccination, and interventions to prevent mother-to-child-transmission of chronic hepatitis B (CHB); and (2) The Healthcare Providers Survey captured individual staff perceptions and knowledge in community and hospital settings.
Objectives: To assess associations between SARS-CoV-2 infection and the incidence of hospitalisation with selected respiratory and non-respiratory conditions in a largely SARS-CoV-2 vaccine-naïve population .
Design, Setting, Participants: Self-control case series; analysis of population-wide surveillance and administrative data for all laboratory-confirmed COVID-19 cases notified to the Victorian Department of Health (onset, 23 January 2020 - 31 May 2021; ie, prior to widespread vaccination rollout) and linked hospital admissions data (admission dates to 30 September 2021).
Main Outcome Measures: Hospitalisation of people with acute COVID-19; incidence rate ratios (IRRs) comparing incidence of hospitalisations with defined conditions (including cardiac, cerebrovascular, venous thrombo-embolic, coagulative, and renal disorders) from three days before to within 89 days of onset of COVID-19 with incidence during baseline period (60-365 days prior to COVID-19 onset).
Background And Objectives: Infant influenza and pertussis disease causes considerable morbidity and mortality worldwide. We examined the effectiveness of maternal influenza and pertussis vaccines in preventing these diseases in infants.
Methods: This inception cohort study comprised women whose pregnancies ended between September 1, 2015, and December 31, 2017, in Victoria, Australia.
Background: Infectious diseases are a leading cause of hospitalization during childhood. The various mitigation strategies implemented to control the coronavirus disease (COVID-19) pandemic could have additional, unintended benefits for limiting the spread of other infectious diseases and their associated burden on the health care system.
Methods: We conducted an interrupted time-series analysis using population-wide hospitalization data for the state of Victoria, Australia.
Commun Dis Intell (2018)
November 2020
Background: Public health surveillance is crucial for supporting a rapid and effective response to public health emergencies. In response to the coronavirus disease (COVID-19) pandemic, an enhanced surveillance system of hospitalised COVID-19 patients was established by the Victorian Department of Health and Human Services (DHHS) and the Victorian Healthcare Associated Infection Surveillance System Coordinating Centre. The system aimed to reduce workforce capacity constraints and increase situational awareness on the status of hospitalised patients.
View Article and Find Full Text PDFObjectives: To assess variations by time of year and hospital in the uptake of influenza and pertussis vaccinations by pregnant women in Victoria; to identify factors associated with vaccination uptake.
Design, Setting: Retrospective analysis of data in the Victorian Perinatal Data Collection (VPDC), a population surveillance system for obstetric conditions, procedures, and pregnancy and birth outcomes.
Participants: Women whose pregnancies ended in a live or stillbirth during July 2015 - June 2017.
Aust N Z J Public Health
February 2019
Objectives: To review the use of data linkage by Australian state and territory communicable disease control units, and to identify barriers to and enablers of data linkage to inform communicable disease surveillance and control activities.
Methods: Semi-structured telephone interviews were carried out with one key informant from communicable disease control units in all eight Australian states and territories between October 2017 and January 2018.
Results: Key informants from all Australian states and territories participated in the interview.
Trop Med Infect Dis
January 2018
Dengue notifications have increased dramatically over the past seven years in Victoria, Australia-a trend which has been seen nationally and reflects increased cases internationally. We reviewed the epidemiology of dengue among Victorian travellers, changes in diagnostic methods and describe the burden placed on local health systems resulting from this disease of public health importance. Cases of dengue notified to the Department of Health and Human Services in Victoria, Australia, between 1 January 2010 and 31 December 2016 were included in this review.
View Article and Find Full Text PDFBackground: During a pertussis epidemic in 2009, the Department of Health, Victoria, Australia, implemented a cocoon program offering parents of new babies a funded-dose of pertussis-containing vaccine. We assessed vaccine effectiveness (VE) of the program in reducing pertussis infection in infants.
Methods: Using a matched case-control design, infants aged <12 months that were notified with pertussis between 1 January 2010 and 31 December 2011, and born during the time that the cocoon program was in place, were identified.