Fatimah S Dawood

Centers for Disease Control and Prevention | CDC · Influenza Division

Importance: Data about the risk of SARS-CoV-2 infection among children compared with adults are needed to inform COVID-19 risk communication and prevention strategies, including COVID-19 vaccination policies for children. Objective: To compare incidence rates and clinical characteristics of SARS-CoV-2 infection among adults and children and esti...

Background: RIV4 and cell-culture based inactivated influenza vaccine (ccIIV4) have not been compared to egg-based IIV4 in healthcare personnel, a population with frequent influenza vaccination that may blunt vaccine immune responses over time. We conducted a randomized trial among HCP aged 18-64 years to compare humoral immune responses to ccIIV4...

18,500 laboratory-confirmed deaths caused by the 2009 pandemic influenza A H1N1 were reported worldwide for the period April, 2009, to August, 2010. This number is likely to be only a fraction of the true number of the deaths associated with 2009 pandemic influenza A H1N1. We aimed to estimate the global number of deaths during the first 12 months...

Background Influenza vaccination during pregnancy prevents influenza among women and their infants but remains underused among pregnant women. We aimed to quantify the risk of antenatal influenza and examine its association with perinatal outcomes. Methods We did a prospective cohort study in pregnant women in India, Peru, and Thailand. Before the...

Background Scant data are available about global patterns of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread and global epidemiology of early confirmed cases of COVID-19 outside mainland China. We describe the global spread of SARS-CoV-2 and characteristics of COVID-19 cases and clusters before the characterisation of COVID-19 a...

This study evaluates the effectiveness of the respiratory syncytial virus vaccine against hospitalization for acute respiratory illness among US adults aged 60 years and older.

Background Assessing variant-specific COVID-19 vaccine effectiveness (VE) and severity can inform public health risk assessments and decisions about vaccine composition. BA.2.86 and its descendants, including JN.1 (referred to collectively as “JN lineages”), emerged in late 2023 and exhibited substantial divergence from co-circulating XBB lineages....

Background: Assessing COVID-19 vaccine effectiveness (VE) and severity of SARS-CoV-2 variants can inform public health risk assessments and decisions about vaccine composition. BA.2.86 and its descendants, including JN.1 (referred to collectively as "JN lineages"), emerged in late 2023 and exhibited substantial genomic divergence from co-circulatin...

This Viewpoint discusses recommendations from the US Centers for Disease Control and Prevention for newly licensed immunizations for respiratory syncytial virus in infants, children with high-risk conditions, and older adults.

Background Data on the characteristics of individuals with mild and asymptomatic infections with different SARS-CoV-2 variants are limited. We therefore compared the characteristics of individuals infected with ancestral, Beta and Delta SARS-CoV-2 variants in South Africa. Methods We conducted a prospective cohort study in a rural and an urban sit...

Respiratory syncytial virus (RSV) is the leading cause of hospitalization among infants in the United States. In August 2023, CDC's Advisory Committee on Immunization Practices recommended nirsevimab, a long-acting monoclonal antibody, for infants aged <8 months to protect against RSV-associated lower respiratory tract infection during their first...

In the United States, annual influenza vaccination is recommended for all persons aged ≥6 months. Using data from four vaccine effectiveness (VE) networks during the 2023-24 influenza season, interim influenza VE was estimated among patients aged ≥6 months with acute respiratory illness-associated medical encounters using a test-negative case-contr...

In September 2023, CDC's Advisory Committee on Immunization Practices recommended updated 2023-2024 (monovalent XBB.1.5) COVID-19 vaccination for all persons aged ≥6 months to prevent COVID-19, including severe disease. However, few estimates of updated vaccine effectiveness (VE) against medically attended illness are available. This analysis evalu...

Background Cesarean delivery rates have increased globally resulting in a public health concern. We estimate rates of cesarean deliveries among Thai women using the World Health Organization (WHO) Robson Classification system and compare rates by Robson group to the Robson guideline for acceptable rates to identify groups that might benefit most fr...

Repeat vaccination with egg-based influenza vaccines could preferentially boost antibodies targeting the egg-adapted epitopes and reduce immunogenicity to circulating viruses. In this randomized trial (Clinicaltrials.gov: NCT03722589), sera pre- and post-vaccination with quadrivalent inactivated egg-based (IIV4), cell culture-based (ccIIV4), and re...

Background Surveillance data from the Influenza Hospitalization Surveillance Network (FluSurv-NET) detected an increase over time in the proportion of hospitalized women of child-bearing age with laboratory-confirmed influenza who were pregnant. We sought to describe changes in patient characteristics to explain this observed trend. Methods FluSur...

Background Data on the characteristics of individuals with mild and asymptomatic infections with different SARS-CoV-2 variants are limited. We therefore compared the characteristics of individuals infected with ancestral, Beta and Delta SARS-CoV-2 variants in South Africa. Methods We conducted a prospective cohort study in a rural and an urban site...

Introduction: With the licensure of maternal RSV vaccines in Europe and USA, data are needed to better characterize the burden of respiratory syncytial virus (RSV)-associated acute respiratory infections (ARI) in pregnancy. This study aims to determine among pregnant individuals the proportion of ARI testing positive for RSV and RSV incidence rate...

During the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, multiple variants escaping preexisting immunity emerged, causing reinfections of previously exposed individuals. Here, we used antigenic cartography to analyze patterns of cross-reactivity among 21 variants and 15 groups of human sera obtained after primary infection...

We examined associations between mild or asymptomatic prenatal SARS‐CoV‐2 infection and preterm live birth in a prospective cohort study. During August 2020–October 2021, pregnant persons were followed with systematic surveillance for RT‐PCR or serologically confirmed SARS‐CoV‐2 infection until pregnancy end. The association between prenatal SARS‐C...

Background: Pregnant women with their infants are considered at higher risk for influenza-associated complications, and the World Health Organization (WHO) recommends influenza vaccination during pregnancy to protect them, including their infants (0–6 months). There are limited data on the influenza burden among pregnant women and their infants (0–...

Background Emerging data suggest second-generation influenza vaccines with higher hemagglutinin (HA) antigen content and/or different production methods may induce stronger antibody responses to HA than standard-dose egg-based influenza vaccines in adults. We compared antibody responses to high-dose egg-based inactivated (HD-IIV3), recombinant (RIV...

Background Early COVID-19 vaccine trials excluded pregnant persons resulting in limited data about immunogenicity and maternal-fetal antibody transfer, particularly by gestational timing of vaccination. Methods In this multi-center observational immunogenicity study, pregnant and non-pregnant women receiving COVID-19 vaccines were prospectively en...

Importance: Associations between prenatal SARS-CoV-2 exposure and neurodevelopmental outcomes have substantial public health relevance. A previous study found no association between prenatal SARS-CoV-2 infection and parent-reported infant neurodevelopmental outcomes, but standardized observational assessments are needed to confirm this finding. O...

Background We compared post-infection SARS-CoV-2 neutralizing antibody (nAb) responses among children and adults while the D614G-like strain and Alpha, Iota and Delta variants circulated. Methods During August 2020–October 2021, households with adults and children were enrolled in Utah, New York City, and Maryland. Participants collected weekly re...

We examined associations between mild or asymptomatic prenatal SARS-CoV-2 infection and preterm live birth in a prospective cohort study. During August 2020–October 2021, pregnant persons were followed with systematic surveillance for RT-PCR or serologically-confirmed SARS-CoV-2 infection until pregnancy end. The association between prenatal SARS-C...

Pregnant women with their infants are considered at higher risk for influenza-associated complications, and the WHO recommends influenza vaccination during pregnancy to protect them, including their infants (0-6 months). There are limited data on the influenza burden among pregnant women and their infants (0-6 months), and there is no routine influ...

Background We measured the immunogenicity of seasonal trivalent inactivated influenza vaccines (IIV3) among older Thai adults and the effect of one-year prior vaccination status on immune responses. Method Adults aged ≥65 years (n = 370) were vaccinated with Southern Hemisphere IIV3 in 2015. Hemagglutination inhibition assays were performed using...

Background Few studies have examined influenza vaccine effectiveness (VE) among women during pregnancy in middle-income countries. We used data from a prospective cohort of women who were pregnant in Peru to estimate effectiveness of the 2018 Southern Hemisphere influenza vaccine. Methods Women at <28 weeks gestation were enrolled from four tertia...

Background: Studies suggest infants may be at increased risk of severe coronavirus disease 2019 (COVID-19) relative to older children, but few data exist regarding the incidence of COVID-19 episodes and associated risk factors. We estimate incidence rates and describe characteristics associated with medically attended COVID-19 episodes among infan...

Background: Millions of children have tested positive for SARS-CoV-2, and over 1000 children have died in the US. However, vaccination rates for children 5 to 11 years old are low. Methods: Starting in August 2020, we conducted a prospective SARS-CoV-2 household surveillance study in Spanish and English-speaking households in New York City and U...

Background During the COVID-19 pandemic, human parainfluenza type 3 (HPIV-3) and respiratory syncytial virus (RSV) circulation increased as non-pharmaceutical interventions were relaxed. Using data from 175 households (n = 690 members) followed between November 2020–October 2021, we characterized HPIV-3 and RSV burden in children aged 0-4 years and...

We performed whole-genome sequencing of SARS-CoV-2 from prospectively identified cases in three longitudinal household cohorts. In a majority of multi-infection households, SARS-CoV-2 consensus sequences were indistinguishable, and they differed by 1 to 2 mutations in the rest.

For public health research such as vaccine uptake or effectiveness assessments, self-reported coronavirus disease 2019 (COVID-19) vaccination status may be a more efficient measure than verifying vaccination status from medical records if agreement between sources is high. We assessed agreement between self-reported and medical record–documented CO...

We conducted weekly surveillance for SARS-CoV-2 infection among a sample of households with ≥1 child aged 0-17 years from selected Utah counties. A Cox proportional hazards model approach was used to calculate infection hazard rate and vaccine effectiveness. Findings show that the recommended primary series of COVID-19 vaccine was effective against...

Influenza testing and case-confirmation rates in pregnant populations have not been reported during the coronavirus disease 2019 (COVID-19) pandemic. Using electronic medical record data from a cohort of nearly 20,000 pregnancies in the United States, this retrospective cohort study examines the frequency of acute respiratory or febrile illness enc...

Early warning and response surveillance (EWARS) systems were widely used during the early COVID-19 response. Evaluating the effectiveness of EWARS systems is critical to ensuring global health security. We describe the Centers for Disease Control and Prevention (CDC) global COVID-19 EWARS (CDC EWARS) system and the resources CDC used to gather, man...

Objective Studies suggest infants may be at increased risk of severe COVID-19 relative to older children, but few data exist regarding the incidence of COVID-19 episodes and associated risk factors. We estimate incidence rates and describe characteristics associated with medically attended COVID-19 episodes among infants younger than 6 months of ag...

Background Estimates of SARS-CoV-2 seroprevalence in young children and risk factors for seropositivity are scarce. Using data from a prospective cohort study of households during the pre-COVID-19 vaccine period, we estimated SARS-CoV-2 seroprevalence by age and evaluated risk factors for SARS-CoV-2 seropositivity. Methods The SARS-CoV-2 Epidemiol...

Importance: Few studies have prospectively assessed SARS-CoV-2 community infection in children aged 0 to 4 years. Information about SARS-CoV-2 incidence and clinical and virological features in young children could help guide prevention and mitigation strategies. Objective: To assess SARS-CoV-2 incidence, clinical and virological features, and s...

Background Antibody responses to non-egg-based standard-dose cell-culture influenza vaccine (containing 15 µg hemagglutinin (HA)/component) and recombinant vaccine (containing 45 µg HA/component) during consecutive seasons have not been studied in the United States. Methods In a randomized trial of immunogenicity of quadrivalent influenza vaccines...

Background Identifying SARS-CoV-2 infections during peripartum hospitalizations is important to guide care, implement prevention measures, and understand infection burden. Methods This cross-sectional analysis used electronic health record data from hospitalizations during which pregnancies ended (peripartum hospitalizations) among a cohort of pre...

Background The reliability of sequence-based inference of SARS-CoV-2 transmission is not clear. Sequence data from infections among household members can define the expected genomic diversity of a virus along a defined transmission chain. Methods SARS-CoV-2 cases were identified prospectively among 2,369 participants in 706 households. Specimens w...

Background Households are common places for spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We investigated factors associated with household transmission and acquisition of SARS-CoV-2. Methods Households with children ages <18 years were enrolled into prospective, longitudinal cohorts and followed August 2020─August 2021 i...

Background Pregnant individuals are at increased risk of COVID-19 hospitalization and death, and primary and booster COVID-19 vaccination is recommended for this population. Methods Among a cohort of pregnant individuals who received prenatal care at three healthcare systems in the United States, we estimated the cumulative incidence of hospitaliz...

Findings from this analysis indicate that (1) self-collection of flocked and foam MTS and saliva samples is feasible in both adults and children, (2) foam MTS with VTM and saliva are both viable and reasonable alternatives to traditional flocked MTS in VTM for SARS-CoV-2 detection, and (3) these sample types may be stored and transported at ambient...

Background: Healthcare personnel (HCP) are a priority group for annual influenza vaccination. Few studies have assessed the validity of recall of prior influenza vaccination status among HCP, especially for more than one preceding season. Methods: Using data from a randomized controlled trial of influenza vaccination among 947 HCP from two US he...

Background: SARS-CoV-2 infections are frequently milder in children than adults, suggesting that immune responses may vary with age. However, information is limited regarding SARS-CoV-2 immune responses in young children. Methods: We compared Receptor Binding Domain binding antibody (RBDAb) titers and SARS-CoV-2 neutralizing antibody titers meas...

Background By August, 2021, South Africa had been affected by three waves of SARS-CoV-2; the second associated with the beta variant and the third with the delta variant. Data on SARS-CoV-2 burden, transmission, and asymptomatic infections from Africa are scarce. We aimed to evaluate SARS-CoV-2 burden and transmission in one rural and one urban com...

Background: Pregnant women may be at increased risk for severe influenza-associated outcomes. Objective: To describe characteristics and outcomes of hospitalized pregnant women with influenza. Design: Repeated cross-sectional study. Setting: The population-based U.S. Influenza Hospitalization Surveillance Network during the 2010-2011 through...

SARS-CoV-2 infections are frequently milder in children than adults, suggesting that immune responses may vary with age. However, information is limited regarding SARS-CoV-2 immune responses in young children. We compared Receptor Binding Domain binding antibody (RBDAb) and SARS-CoV-2 neutralizing antibody (neutAb) in children aged 0-4 years, 5-17...

Objective The aim of the study was to evaluate pregnant women's attitudes toward COVID-19 illness and vaccination and identify factors associated with vaccine acceptability. Study Design This was a cross-sectional survey among pregnant women enrolled in a prospective COVID-19 cohort study in Salt Lake City, UT, Birmingham, AL, and New York, NY, fro...

Background There are limited data on influenza vaccine effectiveness (IVE) in preventing laboratory-confirmed influenza illness among healthcare personnel (HCP). Methods HCP with direct patient contact working full-time in hospitals were followed during three influenza seasons in Israel (2016–2017 to 2018–2019) and Peru (2016 to 2018). Trivalent i...

Background Data about the risk of SARS-CoV-2 infection among pregnant individuals are needed to inform infection prevention guidance and counseling for this population. Methods We prospectively followed a cohort of pregnant individuals during August 2020–March 2021 at three U.S. sites. The three primary outcomes were incidence rates of any SARS-Co...

Background By March 2021, South Africa experienced two waves of SARS-CoV-2 infections; the second associated with emergence of Beta variant. We estimated the burden and transmission of SARS-CoV-2 over the two waves. Methods We conducted a prospective cohort study during July 2020-March 2021 in one rural and one urban community. Mid-turbinate nasal...

Background Seasonal influenza vaccination uptake among young children in Thailand is low despite national recommendation for vaccination. We implemented a knowledge, attitude/perception, and practice survey to understand determinants of influenza vaccination in children aged six months to two years. Methods Using a cross-sectional design, we inter...

Context: Children are at increased risk of influenza-related complications. Public health agencies recommend 2 doses of influenza vaccine for children 6 months through 8 years of age receiving the vaccine for the first time. Objective: To systematically review studies comparing vaccine effectiveness (VE) and immunogenicity after 1 or 2 doses of...

Background We conducted a cross-sectional study of pregnant women with acute respiratory illness during delivery hospitalizations during influenza season to describe clinical testing for respiratory viruses and infection prevention practices. Methods Women had nasal swabs tested for influenza and other respiratory viruses. Among 91 enrolled women,...

Objective: Evaluate pregnant women's attitudes toward COVID-19 illness and vaccination and identify factors associated with vaccine acceptability. Study Design: Cross-sectional survey among pregnant women enrolled in a prospective COVID-19 cohort study in Salt Lake City, UT, Birmingham, AL, and New York, NY, August 9-December 10, 2020. Women were e...

Background Adults with cardiopulmonary conditions may be at increased risk of influenza and respiratory syncytial virus (RSV) infection, but it is not well‐established and few data are available from middle‐income countries. Methods Using data from a prospective cohort study of influenza vaccine effectiveness, we estimated and compared the inciden...

Pneumococcal carriage studies are important for vaccine introduction and treatment strategies. Pneumococcal carriage rates estimated in this cohort study among children in a rural community of northern India. Between August 2012 and August 2014, trained nurses made weekly home visits to screen enrolled children aged <10 years for acute upper or low...

Introduction: We evaluated knowledge, attitudes, and practices (KAP) related to influenza and influenza vaccination among pregnant women in three selected countries. Methods: During 2017, pregnant women seeking antenatal care at hospitals at participating sites were enrolled. We described characteristics and responses to KAP questions. We also eval...

Background: We assessed performance of participant-collected mid-turbinate nasal swabs compared to study staff-collected mid-turbinate nasal swabs for the detection of respiratory viruses among pregnant women in Bangkok, Thailand. Methods: We enrolled pregnant women aged ≥18 years and followed them throughout the 2018 influenza season. Women wit...

We assessed EV‐D68 epidemiology and phylogenetics among children aged ≤9 years hospitalized with severe acute respiratory illnesses at five sites in Panama and El Salvador during 2012‐2013. Respiratory specimens positive for enterovirus or rhinovirus were tested by real‐time RT‐PCR for EV‐D68, and partial VP1 gene sequences were determined. Of 715...

Background We compared cord blood antibody titers in unvaccinated pregnant women to those vaccinated with seasonal influenza vaccine during the 2nd and the 3rd trimesters. Methods Pregnant women had cord blood collected at delivery for hemagglutination inhibition assay against vaccine reference viruses: A/California/07/2009 (H1N1)pdm09, A/Switzerl...

Background The World Health Organization (WHO) recommends case definitions for influenza surveillance that are also used in public health research, though their performance has not been assessed in many risk groups, including pregnant women in whom influenza may manifest differently. We evaluated the performance of symptom-based definitions to dete...

Introduction and Objectives: Despite a growing population of persons aged >60 years in middle-income countries, few data are available on the burden of influenza among older adults in India. We conducted a prospective multi-site cohort study among community dwelling adults aged >60 years to estimate the incidence of influenza-associated acute respi...

Background The Estudio Vacuna de Influenza Peru (VIP) cohort aims to describe the frequency of influenza virus infection, identify predictors of vaccine acceptance, examine the effects of repeated influenza vaccination on immunogenicity, and evaluate influenza vaccine effectiveness among HCP. Methods The VIP cohort prospectively followed HCP in Li...