Justin R Ortiz

University of Maryland, Baltimore | UMB

In 2017, WHO convened a working group of global experts to develop the Preferred Product Characteristics (PPC) for Next-Generation Influenza Vaccines. PPCs are intended to encourage innovation in vaccine development. They describe WHO preferences for parameters of vaccines, in particular their indications, target groups, implementation strategies,...

Objectives The aim of this systematic review was to assess incidence rates of laboratory-confirmed influenza (LCI) outcomes among infants under 6 months of age. Design Systematic literature search and review of indexed studies in PubMed, EMBASE, the Cochrane Library and CINAHL Plus from inception to 19 April 2017. Setting Population-based estimat...

From 2014 to 2017, the World Health Organization convened a working group to evaluate influenza disease burden and vaccine efficacy to inform estimates of maternal influenza immunization program impact. The group evaluated existing systematic reviews and relevant primary studies, and conducted four new systematic reviews. There was strong evidence...

Maternal influenza vaccination prevents influenza illness in both mothers and newborns. Results from some recent studies have suggested that influenza vaccination might also prevent adverse pregnancy outcomes, such as preterm birth. However, it is challenging to conduct epidemiologic studies to evaluate the benefits to the fetus of maternal influen...

The emergence of a novel strain of influenza virus A (H1N1) in April 2009 focused attention on influenza surveillance capabilities worldwide. In consultations before the 2009 outbreak of influenza subtype H1N1, the World Health Organization had concluded that the world was unprepared to respond to an influenza pandemic, due in part to inadequate gl...

In a population-based birth cohort study of respiratory syncytial virus surveillance in the United States, 897/1,680 (53.4%) children were infected during infancy; 25 (2.8%) of those were hospitalized. Among symptomatic infants, 143/324 (44.1%) had lower respiratory tract infections. These data provide benchmarks to monitor effects of maternal vacc...

Importance Acute respiratory tract infections are the leading cause of emergency department visits and hospitalizations in US children, with highest risks in the first 2 months after birth. Out-of-home childcare settings increase the spread of respiratory tract infections. The study team hypothesized that access to state-paid family leave could red...

Glucagon-like peptide-1 (GLP-1) is a gastrointestinal regulatory hormone that stimulates insulin release from the pancreas. While GLP-1 receptor agonists (GLP-1 RAs) have traditionally been utilized to address insulin resistance, their potential application in treating polycystic ovary syndrome (PCOS) has recently garnered attention. This study aim...

Background Although antivirals remain important for the treatment COVID-19, methods to assess treatment efficacy are lacking. Here, we investigated the impact of remdesivir on viral dynamics and their contribution to understanding antiviral efficacy in the multicenter ACTT-1 clinical trial that randomized patients to remdesivir or placebo. Methods...

Background Adults ≥ 65 years of age have suboptimal influenza vaccination responses compared to younger adults due to age‐related immunosenescence. Two vaccines were specifically developed to enhance protection: MF59‐adjuvanted trivalent influenza vaccine (aIIV3) and high‐dose egg‐based trivalent influenza vaccine (HD‐IIV3e). Methods In a retrospe...

Policymakers often rely on impact and cost-effectiveness evaluations to inform decisions about the introduction of health interventions in low- and middle-income countries (LMICs); however, cost-effectiveness results for the same health intervention can differ by the choice of parameter inputs, modelling assumptions, and geography. Anticipating the...

Background: Influenza A (H7N9) has caused multiple disease waves with evidence of strain diversification. Optimal influenza A (H7N9) prime-boost vaccine strategies are unknown. Methods: We recruited participants who had received monovalent inactivated A/Shanghai/2/2013 (H7N9) vaccine (MIV) approximately 5 years earlier, as follows: MIV with MF59...

Respiratory syncytial virus (RSV) is the predominant cause of acute lower respiratory infection (ALRI) in young children worldwide, yet no licensed RSV vaccine exists to help prevent the millions of illnesses and hospitalizations and tens of thousands of young lives taken each year. Monoclonal antibody (mAb) prophylaxis exists for prevention of RSV...

Background The mammalian cell-based quadrivalent inactivated influenza vaccine (IIV4c) has advantages over egg-based quadrivalent inactivated influenza vaccine (IIV4e), as production using cell-derived candidate viruses eliminates the opportunity for egg-adaptation. This study estimated the relative vaccine effectiveness (rVE) of IIV4c vs IIV4e in...

Background The Global Influenza Hospital Surveillance Network (GIHSN) was established in 2012 to conduct coordinated worldwide influenza surveillance. Here we describe underlying comorbidities, symptoms, and outcomes in hospitalized patients with influenza. Methods Between November/2018 and October/2019, GIHSN included 19 sites in 18 countries usi...

Respiratory syncytial virus (RSV) is the most common cause of early childhood lower respiratory tract infection (LRTI) in low- and middle-income countries (LMICs). Maternal vaccines, birth-dose extended half-life monoclonal antibodies (mAbs), and pediatric vaccines are under development for prevention of respiratory syncytial virus (RSV) lower resp...

Background: Respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract infection (LRTI) in young children and is associated with subsequent recurrent wheezing illness and asthma (wheeze/asthma). RSV prevention may therefore reduce wheeze/asthma prevalence. Objectives: We estimated the contribution of RSV LRTI and the impact...

Background: We evaluated the associations between baseline influenza virus-specific hemagglutination inhibition (HAI) and microneutralization (MN) titers and subsequent symptomatic influenza virus infection in a controlled human infection study. Methods: We inoculated unvaccinated healthy adults aged 18 through 49 years with an influenza A/Calif...

Background Influenza A/H5N8 viruses infect poultry and wild birds in many countries. In 2021, the first human A/H5N8 cases were reported. Methods We conducted a phase I, cohort-randomized, double-blind, controlled trial of inactivated influenza A/H5N8 vaccine (clade 2.3.4.4c) administered with or without adjuvant. Cohort 1 subjects received either...

Background Influenza virus infection is associated with incident ischemic heart disease (IHD) events. Here, we estimate the global, regional, and national IHD mortality burden attributable to influenza. Methods We used vital registration data from deaths in adults ≥50 years (13.2 million IHD deaths as underlying cause) to assess the relationship b...

Background Influenza vaccines require yearly updates due to constant antigenic drift. Improvement of current vaccines requires a deep understanding of the pathogen as well as immunity to the virus. Controlled Human Infection Models (CHIM) provide opportunities to i) test new vaccine approaches in a controlled environment and, ii) better understand...

Background Mutations occurring during egg-based influenza vaccine production may affect vaccine effectiveness. The mammalian cell-based quadrivalent inactivated influenza vaccine (IIV4c) demonstrated improved protection relative to egg-based vaccines in prior seasons. This study estimated the relative vaccine effectiveness (rVE) of IIV4c versus sta...

Rationale: Influenza controlled human infection model (CHIM) studies can advance development of vaccines and therapeutics. Objectives: Our objective was to evaluate the associations between baseline challenge virus-specific hemagglutination inhibition (HAI) and microneutralization (MN) titers and subsequent symptomatic influenza virus infection. Me...

Traditional influenza vaccines may be less immunogenic in adults ≥ 65 years of age due to immunosenescence. Two influenza vaccines-MF59®-adjuvanted trivalent inactivated influenza vaccine (aIIV3) and high-dose influenza vaccine (HD-IIV3)-were developed to overcome this problem. We summarize estimates of the relative vaccine effectiveness (rVE) of a...

Background: Egg-based influenza vaccine production can lead to the accumulation of mutations that affect antigenicity. The mammalian cell-based inactivated quadrivalent influenza vaccine (IIV4c) may improve effectiveness compared with egg-based vaccines. This study estimated the relative vaccine effectiveness (rVE) of IIV4c versus egg-based inacti...

Introduction We conducted a systematic review of pediatric influenza vaccine efficacy trials to assess clinical outcome measures and whether the trials defined important public health endpoints. Material and methods We systematically identified phase 3 or 4 influenza vaccine randomized controlled trials among children ≤18 years of age with laborat...

The adaptation of influenza seed viruses in egg culture can result in a variable antigenic vaccine match each season. The cell-based quadrivalent inactivated influenza vaccine (IIV4c) contains viruses grown in mammalian cell lines rather than eggs. IIV4c is not subject to egg-adaptive changes and therefore may offer improved protection relative to...

Background Respiratory syncytial virus (RSV) is the most common cause of early childhood lower respiratory tract infection (LRTI) in low- and middle-income countries (LMICs). Maternal vaccines, birth-dose extended half-life monoclonal antibodies (mAbs), and pediatric vaccines are under development for prevention of respiratory syncytial virus (RSV)...

Real-world evidence (RWE) increasingly informs public health and healthcare decisions worldwide. A large database has been created (“Integrated Dataset”) that integrates primary care electronic medical records with pharmacy and medical claims data on >123 million US patients since 2014. This article describes the components of the Integrated Datase...

Background Influenza A/H7N9 viruses have pandemic potential. Methods We conducted an open-label, randomized, controlled trial of AS03-adjuvanted 2017 inactivated influenza A/H7N9 vaccine (H7N9 IIV) in healthy adults. Group 1 received H7N9 IIV and seasonal quadrivalent influenza vaccine (IIV4) simultaneously, followed by H7N9 IIV three weeks later....

Background: Age-related immunosenescence may impair the immune response to vaccination in older adults. Adjuvanted influenza vaccines are designed to overcome immune senescence in older adults. This study estimated the relative vaccine effectiveness (rVE) of MF59®-adjuvanted trivalent inactivated influenza vaccine (aIIV3) versus egg-derived quadriv...

Background Age-related immunosenescence may impair the immune response to vaccination in older adults. Adjuvanted influenza vaccines are designed to overcome immune senescence in older adults. This study estimated the relative vaccine effectiveness (rVE) of MF59®-adjuvanted trivalent inactivated influenza vaccine (aIIV3) versus egg-derived quadriva...

In this cohort study of hospitalized patients with linked medical record data, we developed International Classification of Diseases (ICD) criteria that accurately identified laboratory-confirmed, severe influenza hospitalizations (positive predictive value [PPV] 80%, 95% confidence interval [CI] 71–87%), which we validated through medical record d...

(Abstracted from JAMA 2021;325:2285–2293) Vaccination for seasonal influenza is an important health intervention, even for pregnant women. Influenza vaccination helps to reduce the risk of severe influenza illness for the mother and child.

Importance Low- and middle-income countries have a high burden of respiratory syncytial virus lower respiratory tract infections. A monoclonal antibody administered monthly is licensed to prevent these infections, but it is cost-prohibitive for most low- and middle-income countries. Long-acting monoclonal antibodies and maternal vaccines against re...

We sought to validate prognostic scores in coronavirus disease 2019 including National Early Warning Score, Modified Early Warning Score, and age-based modifications, and define their performance characteristics. Design: We analyzed prospectively collected data from the Adaptive COVID-19 Treatment Trial. National Early Warning Score was collected...

Importance Seasonal influenza vaccination in pregnancy can reduce influenza illness among pregnant women and newborns. Evidence is limited on whether seasonal influenza vaccination in pregnancy is associated with adverse childhood health outcomes. Objective To assess the association between maternal influenza vaccination during pregnancy and early...

Phase 3 randomized-controlled trials have provided promising results of COVID-19 vaccine efficacy, ranging from 50-95% against symptomatic disease as the primary endpoints, resulting in emergency use authorization/listing for several vaccines. However, given the short duration of follow-up during the clinical trials, strict eligibility criteria, em...

Background: Influenza vaccination is uncommon in low-resource settings. We evaluated aspects of operational feasibility of influenza vaccination programs targeting risk groups in the WHO African (AFR) and South-East Asian (SEAR) Regions. Methods: We estimated routine immunization and influenza vaccination campaign doses, doses per vaccinator, an...

Introduction As SARS-CoV-2 disproportionately affects adults, the COVID-19 pandemic vaccine response will rely on adult immunisation infrastructures. Aim To assess adult immunisation programmes in World Health Organization (WHO) Member States. Methods We evaluated country reports from 2018 on adult immunisation programmes sent to WHO and UNICEF....

COVID-19 vaccines are now being deployed as essential tools in the public health response to the global SARS-CoV-2 pandemic. Pregnant individuals are a unique subgroup of the population with distinctive considerations regarding risk and benefit that extend beyond themselves to their fetus/newborn. As a complement to traditional pharmacovigilance an...

Background SARS-CoV-2 vaccines will be deployed to countries with limited immunization systems. Methods We assessed the effect of deploying SARS-Cov-2 vaccines on cold storage capacity and immunization workload in a simulated WHO African Region country using region-specific data on immunization, population, healthcare workers (HCWs), cold storage...

This is a Brighton Collaboration Case Definition of the term “Acute Respiratory Distress Syndrome - ARDS” to be utilized in the evaluation of adverse events following immunization. The Case Definition was developed by a group of experts convened by the Coalition for Epidemic Preparedness Innovations (CEPI) in the context of active development of va...

Background: We report results of Years 2 and 3 of consecutive cluster-randomized controlled trials of trivalent inactivated influenza vaccine (IIV3) in Senegal. Methods: We cluster-randomized (1:1) 20 villages to annual vaccination with IIV3 or inactivated poliovirus vaccine (IPV) of age-eligible residents (6 months - 10 years). The primary outcom...

Introduction As the SARS-CoV-2 pandemic disproportionately affects older adults, future pandemic vaccine response will rely on existing adult immunization infrastructures. Methods We evaluated the 2018 WHO/UNICEF Joint Reporting Form on Immunization for country reports on adult immunization programs. We described countries with programs and used m...

Final report of ACCT-1

Data on influenza vaccine immunogenicity in children are limited from tropical developing countries. We recently reported significant, moderate effectiveness of a trivalent inactivated influenza vaccine (IIV) in a controlled, cluster-randomized trial in children in rural Senegal during 2009, a year of H3N2 vaccine mis-match (NCT00893906). We report...

Background: After SARS-CoV-2 vaccines become available, they will be deployed to many countries with limited immunization systems. Methods: We conducted a cold chain capacity assessment of a simulated country in the WHO African Region. We combined region-specific data regarding immunization, population, healthcare workforce, and cold storage capac...

Background Although a positive association has been established, it is unclear whether lower respiratory tract infections (LRTIs) with respiratory syncytial virus (RSV) cause chronic wheezing illnesses. If RSV-LRTI were causal, we would expect RSV-LRTI prevention to reduce the incidence of chronic wheezing illnesses in addition to reducing acute di...

Background: Since 2011, the Global Influenza Hospital Surveillance Network (GIHSN) has used active surveillance to prospectively collect epidemiological and virological data on patients hospitalized with influenza virus infection. Here, we describe influenza virus strain circulation in the GIHSN participant countries during 2017-2018 season and ex...

Background Previous attempts to characterise the burden of chronic respiratory diseases have focused only on specific disease conditions, such as chronic obstructive pulmonary disease (COPD) or asthma. In this study, we aimed to characterise the burden of chronic respiratory diseases globally, providing a comprehensive and up-to-date analysis on ge...

Background Maternal influenza immunisation can reduce morbidity and mortality associated with influenza infection in pregnant women and young infants. We aimed to determine the vaccine efficacy of maternal influenza immunisation against maternal and infant PCR-confirmed influenza, duration of protection, and the effect of gestational age at vaccina...

Background Although several therapeutic agents have been evaluated for the treatment of coronavirus disease 2019 (Covid-19), none have yet been shown to be efficacious. Methods We conducted a double-blind, randomized, placebo-controlled trial of intravenous remdesivir in adults hospitalized with Covid-19 with evidence of lower respiratory tract in...

Ecologic models of influenza burden may be confounded by other exposures that share winter seasonality. We evaluated the effects of air pollution and other environmental exposures in ecologic models estimating influenza-associated hospitalizations. We linked hospitalization data, viral surveillance, and environmental data, including temperature, re...

Background: Since 2011, the Global Influenza Hospital Surveillance Network (GIHSN) has used active surveillance to prospectively collect epidemiological and virological data on patients hospitalized with influenza virus infection. Here, we describe influenza virus strain circulation in the GIHSN participant countries during 2017–2018 season and exa...

Respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract infection (LRTI) and hospitalization in infants and children globally. Many observational studies have found an association between RSV LRTI in early life and subsequent respiratory morbidity, including recurrent wheeze of early childhood (RWEC) and asthma. Conversely,...

Background: Standard-dose, seasonal, trivalent, inactivated influenza vaccine induces moderate-to-low haemagglutination-inhibition antibody responses in people living with HIV. This study assessed the immunogenicity and safety of different dosing schedules of inactivated influenza vaccine in pregnant women living with HIV in South Africa. Methods...

Background: WHO identifies pregnant women to be at increased risk for severe outcomes from influenza virus infections and recommends that they be prioritized for influenza vaccination. The evidence supporting this, however, is inconsistent. Ecologic studies in particular suggest more severe outcomes from influenza infection during pregnancy than s...