Now showing items 21-40 of 1620

    • Increasing pneumococcal vaccine uptake in older adults: a scoping review of interventions in high-income countries

      Kirubarajan, Abirami; Lynch, Meghan; Nasreen, Sharifa; Gebretekle, Gebremedhin B.; Fadel, Shaza A.; Crowcroft, Natasha S.; Allin, Sara (Springer Science and Business Media LLC, 2023-01-02)
      Background: There is low uptake of the pneumococcal vaccination in eligible older adults, even in high-income countries that offer routine and universal vaccination programs. Objective: To systematically characterize interventions aimed at improving pneumococcal vaccine uptake in older adults. Design: We conducted a scoping review following PRISMA-SCr guidelines of five interdisciplinary databases: Medline-Ovid, Embase, CINAHL, PsychInfo, and Cochrane Library. Databases were searched from January 2015 until April 2020. The interventions were summarized into three pillars according to the European Union Conceptional Framework for Action: information campaigns, prioritization of vaccination schemes, and primary care interventions. Results: Our scoping review included 39 studies that summarized interventions related to pneumococcal vaccine uptake for older adults, encompassing 2,481,887 study participants (945 healthcare providers and 2,480,942 older adults) across seven countries. Examples of interventions that were associated with increased pneumococcal vaccination rate included periodic health examinations, reminders and decision-making tools built into electronic medical records, inpatient vaccination protocols, preventative health checklists, and multimodal educational interventions. When comparing the three pillars, prioiritization of vaccination schemes had the highest evidence for improved rates of vaccination (n = 14 studies), followed by primary care interventions (n = 8 studies), then information campaigns (n = 5 studies). Conclusion: Several promising interventions were associated with improved outcomes related to vaccine uptake, although controlled study designs are needed to determine which interventions are most effective.
    • Is pregnancy a teachable moment to promote handwashing with soap among primiparous women in rural Bangladesh? Follow‐up of a randomised controlled trial

      Kamm, Kelly B.; Vujcic, Jelena; Nasreen, Sharifa; Luby, Stephen P.; Zaman, K.; El Arifeen, Shams; Ram, Pavani K. (Wiley, 2016-10-10)
      Objective: Promoting handwashing with soap to mothers of young children can significantly reduce diarrhoea and pneumonia morbidity among children, but studies that measured long-term behaviour after interventions rarely found improvements in handwashing habits. Expecting mothers may experience emotional and social changes that create a unique environment that may encourage adoption of improved handwashing habits. The objective of this study was to determine whether exposure to an intensive handwashing intervention in the perinatal period (perinatal arm) was associated with improved maternal handwashing behaviour vs. exposure to the same intervention after the end of the perinatal period (post-neonatal arm). Methods: We identified primiparous women previously enrolled a randomised controlled handwashing intervention trial (November 2010-December 2011) and observed handwashing behaviours at the home 1-14 months after completion of the RCT (January-May 2012). We observed maternal handwashing and estimated the prevalence ratio (PR) of maternal handwashing using log-binomial regression. Results: We enrolled 107 mothers in the perinatal arm and 105 mothers in the post-neonatal arm. Handwashing with soap at recommended times was low overall (4.6%) and comparable between arms (PR = 0.9, 95% CI 0.5, 1.5). Conclusions: This handwashing intervention was unable to develop and establish improved handwashing practices in primiparous women in rural Bangladesh. While pregnancy may present an opportunity and motivation to do so, further studies should assess whether social, individual and environmental influences overcome this motivation and prevent handwashing with soap among new mothers.
    • Estimating population-based incidence of community-acquired pneumonia and acute otitis media in children and adults in Ontario and British Columbia using health administrative data, 2005–2018: a Canadian Immunisation Research Network (CIRN) study

      Nasreen, Sharifa; Wang, Jun; Sadarangani, Manish; Kwong, Jeffrey C; Quach, Caroline; Crowcroft, Natasha S; Wilson, Sarah E; McGeer, Allison; Morris, Shaun K; Kellner, James D; et al. (BMJ, 2022-06-28)
      Background: There is a paucity of data on the burden of the full spectrum of community-acquired pneumonia (CAP) and acute otitis media (AOM) from outpatient and inpatient settings across the age spectrum. Methods: We conducted a population-based retrospective study in Ontario and British Columbia (BC), Canada, to estimate the incidence rate of CAP and AOM in children and adults over a 14-year period using health administrative databases. CAP and AOM cases were identified from outpatient physician consultation and hospitalisation data in both provinces, and from emergency department visit data in Ontario. Results: During 2005-2018, Ontario had 3 607 124 CAP, 172 290 bacterial CAP, 7814 pneumococcal pneumonia, and 8 026 971 AOM cases. The incidence rate of CAP declined from 3077/100 000 in 2005 to 2604/100 000 in 2010 before increasing to 2843/100 000 in 2018; bacterial CAP incidence rate also declined from 178/100 000 in 2005 to 112/100 000 in 2010 before increasing to 149/100 000 in 2018. The incidence rate of AOM decreased from 4192/100 000 in 2005 to 3178/100 000 in 2018. BC had 970 455 CAP, 317 913 bacterial CAP, 35 287 pneumococcal pneumonia and 2 022 871 AOM cases. The incidence rate of CAP in BC decreased from 2214/100 000 in 2005 to 1964/100 000 in 2010 before increasing to 2176/100 000 in 2018; bacterial CAP incidence rate increased from 442/100 000 in 2005 to 981/100 000 in 2018. The incidence rate of AOM decreased from 3684/100 000 in 2005 to 2398/100 000 in 2018. The incidence rate of bacterial CAP increased with age in older adults (≥65 years) with the highest burden in the oldest cohort aged ≥85 years both before and after 13-valent pneumococcal conjugate vaccine (PCV13) programme in both provinces. Hospitalised pneumococcal pneumonia decreased slightly but non-hospitalised pneumococcal pneumonia increased in BC during PCV13 period. No consistent direct benefit of PCV13 on CAP was observed in the paediatric population. Conclusions: There is a substantial burden of CAP and AOM in Ontario and BC. Indirect benefits from childhood PCV vaccination and polysaccharide vaccination of older adults have not substantially decreased the burden of pneumococcal pneumonia in older adults.
    • Effectiveness of COVID-19 Vaccines Over Time Prior to Omicron Emergence in Ontario, Canada: Test-Negative Design Study

      Chung, Hannah; Austin, Peter C; Brown, Kevin A; Buchan, Sarah A; Fell, Deshayne B; Fong, Cindy; Gubbay, Jonathan B; Nasreen, Sharifa; Schwartz, Kevin L; Sundaram, Maria E; et al. (Oxford University Press (OUP), 2022-09-07)
      Background: Waning protection from 2 doses of coronavirus disease 2019 (COVID-19) vaccines led to third dose availability in multiple countries even before the emergence of the Omicron variant. Methods: We used the test-negative study design to estimate vaccine effectiveness (VE) against any severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, any symptomatic infection, and severe outcomes (COVID-19-related hospitalizations or death) by time since second dose of any combination of BNT162b2, mRNA-1273, and ChAdOx1 between January 11, and November 21, 2021, for subgroups based on patient and vaccine characteristics. Results: We included 261 360 test-positive cases (of any SARS-CoV-2 lineage) and 2 783 699 individuals as test-negative controls. VE of 2 mRNA vaccine doses decreased from 90% (95% CI, 90%-90%) 7-59 days after the second dose to 75% (95% CI, 72%-78%) after ≥240 days against infection, decreased from 94% (95% CI, 84%-95%) to 87% (95% CI, 85%-89%) against symptomatic infection, and remained stable (98% [95% CI, 97%-98%] to 98% [95% CI, 96%-99%]) against severe outcomes. Similar trends were seen with heterologous ChAdOx1 and mRNA vaccine schedules. VE estimates for dosing intervals <35 days were lower than for longer intervals (eg, VE of 2 mRNA vaccines against symptomatic infection at 120-179 days was 86% [95% CI, 85%-88%] for dosing intervals <35 days, 92% [95% CI, 91%-93%] for 35-55 days, and 91% [95% CI, 90%-92%] for ≥56 days), but when stratified by age group and subperiod, there were no differences between dosing intervals. Conclusions: Before the emergence of Omicron, VE of any 2-dose primary series, including heterologous schedules and varying dosing intervals, decreased over time against any infection and symptomatic infection but remained high against severe outcomes.
    • Asthma exacerbation trajectories and their predictors in children with incident asthma

      Nasreen, Sharifa; Wilk, Piotr; Mullowney, Tara; Karp, Igor (Elsevier BV, 2019-09)
      Background: Asthma exacerbation trajectories in children after incident asthma diagnosis are understudied. Objective: To identify trajectories of asthma exacerbation and predictors of these trajectories in children with incident asthma. Methods: Children from the National Longitudinal Survey of Children and Youth, Canada, with incident asthma were followed-up for up to 12 years during childhood. Latent class growth modeling was used to identify distinct asthma exacerbation trajectory groups. Multinomial logistic regression was performed to identify predictors of trajectory group membership. Results: The mean age at asthma diagnosis among 403 children was 5.9 years. Three distinct trajectories were identified: low increasing (21.3% of children), medium decreasing (45.8% of children), and high decreasing (32.8% of children). Asthma attack probability increased gradually after diagnosis in low increasing group, decreased from moderate level after diagnosis to almost zero probability at the end of follow-up in the medium decreasing group, and decreased after diagnosis but remained higher in the high decreasing group than the other 2 groups at 12 years after diagnosis. Children having more siblings at home were more likely to belong to the medium decreasing and high decreasing trajectory groups, whereas children older at asthma diagnosis were less likely to belong to the medium decreasing and high decreasing trajectory groups than the low increasing trajectory group. Conclusion: Our results suggest that children with incident asthma follow 3 distinct trajectories of asthma exacerbations after asthma diagnosis. The trajectory group with initial moderate exacerbation probability has better long-term prognosis.
    • Background rates of adverse events of special interest for COVID-19 vaccines: A multinational Global Vaccine Data Network (GVDN) analysis

      Phillips, A.; Jiang, Y.; Walsh, D.; Andrews, N.; Artama, M.; Clothier, H.; Cullen, L.; Deng, L.; Escolano, S.; Gentile, A.; et al. (Elsevier BV, 2023-10)
      Background: The Global COVID Vaccine Safety (GCoVS) project was established in 2021 under the multinational Global Vaccine Data Network (GVDN) consortium to facilitate the rapid assessment of the safety of newly introduced vaccines. This study analyzed data from GVDN member sites on the background incidence rates of conditions designated as adverse events of special interest (AESI) for COVID-19 vaccine safety monitoring. Methods: Eleven GVDN global sites obtained data from national or regional healthcare databases using standardized methods. Incident events of 13 pre-defined AESI were included for a pre-pandemic period (2015-19) and the first pandemic year (2020). Background incidence rates (IR) and 95% confidence intervals (CI) were calculated for inpatient and emergency department encounters, stratified by age and sex, and compared between pre-pandemic and pandemic periods using incidence rate ratios. Results: An estimated 197 million people contributed 1,189,652,926 person-years of follow-up time. Among inpatients in the pre-pandemic period (2015-19), generalized seizures were the most common neurological AESI (IR ranged from 22.15 [95% CI 19.01-25.65] to 278.82 [278.20-279.44] per 100,000 person-years); acute disseminated encephalomyelitis was the least common (<0.5 per 100,000 person-years at most sites). Pulmonary embolism was the most common thrombotic event (IR 45.34 [95% CI 44.85-45.84] to 93.77 [95% CI 93.46-94.08] per 100,000 person-years). The IR of myocarditis ranged from 1.60 [(95% CI 1.45-1.76) to 7.76 (95% CI 7.46-8.08) per 100,000 person-years. The IR of several AESI varied by site, healthcare setting, age and sex. The IR of some AESI were notably different in 2020 compared to 2015-19. Conclusion: Background incidence of AESIs exhibited some variability across study sites and between pre-pandemic and pandemic periods. These findings will contribute to global vaccine safety surveillance and research.
    • Effectiveness of mRNA COVID-19 Monovalent and Bivalent Vaccine Booster Doses Against Omicron Severe Outcomes Among Adults Aged ≥50 Years in Ontario, Canada: A Canadian Immunization Research Network Study

      Grewal, Ramandip; Buchan, Sarah A; Nguyen, Lena; Nasreen, Sharifa; Austin, Peter C; Brown, Kevin A; Gubbay, Jonathan; Lee, Nelson; Schwartz, Kevin L; Tadrous, Mina; et al. (Oxford University Press (OUP), 2023-10-05)
      We estimated the effectiveness of booster doses of monovalent and bivalent mRNA COVID-19 vaccines against Omicron-associated severe outcomes among adults aged ≥50 years in Ontario, Canada. Monovalent and bivalent mRNA COVID-19 booster doses provided similar strong initial protection against severe outcomes. Uncertainty remains around waning of protection from these vaccines.
    • Background incidence rates of adverse events of special interest related to COVID-19 vaccines in Ontario, Canada, 2015 to 2020, to inform COVID-19 vaccine safety surveillance

      Nasreen, Sharifa; Calzavara, Andrew; Buchan, Sarah A.; Thampi, Nisha; Johnson, Caitlin; Wilson, Sarah E.; Kwong, Jeffrey C. (Elsevier BV, 2022-05)
      Background: Background incidence rates are critical in pharmacovigilance to facilitate identification of vaccine safety signals. We estimated background incidence rates of 11 adverse events of special interest related to COVID-19 vaccines in Ontario, Canada. Methods: We conducted a population-based retrospective observational study using linked health administrative databases for hospitalizations and emergency department visits among Ontario residents. We estimated incidence rates of Bell's palsy, idiopathic thrombocytopenia, febrile convulsions, acute disseminated encephalomyelitis, myocarditis, pericarditis, Kawasaki disease, Guillain-Barré syndrome, transverse myelitis, acute myocardial infarction, and anaphylaxis during five pre-pandemic years (2015-2019) and 2020. Results: The average annual population was 14 million across all age groups with 51% female. The pre-pandemic mean annual rates per 100,000 population during 2015-2019 were 191 for acute myocardial infarction, 43.9 for idiopathic thrombocytopenia, 28.8 for anaphylaxis, 27.8 for Bell's palsy, 25.0 for febrile convulsions, 22.8 for acute disseminated encephalomyelitis, 11.3 for myocarditis/pericarditis, 8.7 for pericarditis, 2.9 for myocarditis, 2.0 for Kawasaki disease, 1.9 for Guillain-Barré syndrome, and 1.7 for transverse myelitis. Females had higher rates of acute disseminated encephalomyelitis, transverse myelitis and anaphylaxis while males had higher rates of myocarditis, pericarditis, and Guillain-Barré syndrome. Bell's palsy, acute disseminated encephalomyelitis, and Guillain-Barré syndrome increased with age. The mean rates of myocarditis and/or pericarditis increased with age up to 79 years; males had higher rates than females: from 12 to 59 years for myocarditis and ≥12 years for pericarditis. Febrile convulsions and Kawasaki disease were predominantly childhood diseases and generally decreased with age. Conclusions: Our estimated background rates will permit estimating numbers of expected events for these conditions and facilitate detection of potential safety signals following COVID-19 vaccination.
    • Effectiveness of Coronavirus Disease 2019 Vaccines Against Hospitalization and Death in Canada: A Multiprovincial, Test-Negative Design Study

      Nasreen, Sharifa; Febriani, Yossi; Velásquez García, Héctor Alexander; Zhang, Geng; Tadrous, Mina; Buchan, Sarah A; Righolt, Christiaan H; Mahmud, Salaheddin M; Janjua, Naveed Zafar; Krajden, Mel; et al. (Oxford University Press (OUP), 2022-08-17)
      Background: A major goal of coronavirus disease 2019 (COVID-19) vaccination is to prevent severe outcomes (hospitalizations and deaths). We estimated the effectiveness of messenger RNA (mRNA) and ChAdOx1 COVID-19 vaccines against severe outcomes in 4 Canadian provinces between December 2020 and September 2021. Methods: We conducted this multiprovincial, retrospective, test-negative study among community-dwelling adults aged ≥18 years in Ontario, Quebec, British Columbia, and Manitoba using linked provincial databases and a common study protocol. Multivariable logistic regression was used to estimate province-specific vaccine effectiveness against COVID-19 hospitalization and/or death. Estimates were pooled using random-effects models. Results: We included 2 508 296 tested participants, with 31 776 COVID-19 hospitalizations and 5842 deaths. Vaccine effectiveness was 83% after a first dose and 98% after a second dose against both hospitalization and death (separately). Against severe outcomes, effectiveness was 87% (95% confidence interval [CI], 71%-94%) ≥84 days after a first dose of mRNA vaccine, increasing to 98% (95% CI, 96%-99%) ≥112 days after a second dose. Vaccine effectiveness against severe outcomes for ChAdOx1 was 88% (95% CI, 75%-94%) ≥56 days after a first dose, increasing to 97% (95% CI, 91%-99%) ≥56 days after a second dose. Lower 1-dose effectiveness was observed for adults aged ≥80 years and those with comorbidities, but effectiveness became comparable after a second dose. Two doses of vaccines provided very high protection for both homologous and heterologous schedules and against Alpha, Gamma, and Delta variants. Conclusions: Two doses of mRNA or ChAdOx1 vaccine provide excellent protection against severe outcomes.
    • Newborn and Early Infant Outcomes Following Maternal COVID-19 Vaccination During Pregnancy

      Jorgensen, Sarah C. J.; Drover, Samantha S. M.; Fell, Deshayne B.; Austin, Peter C.; D’Souza, Rohan; Guttmann, Astrid; Buchan, Sarah A.; Wilson, Sarah E.; Nasreen, Sharifa; Schwartz, Kevin L.; et al. (American Medical Association (AMA), 2023-12-01)
      Importance: The study team previously showed that maternal mRNA COVID-19 vaccination during pregnancy confers protection against SARS-CoV-2 infection and COVID-19-related hospital admission in newborns and young infants. In this study, the study team evaluated newborn and early infant safety outcomes following maternal messenger RNA (mRNA) COVID-19 vaccination during pregnancy, for which there is limited comparative epidemiological evidence. Objective: To determine if maternal mRNA COVID-19 vaccination during pregnancy is associated with adverse newborn and early infant outcomes. Design, setting, and participants: This population-based retrospective cohort study took place in Ontario, Canada, using multiple linked health administrative databases. Singleton live births with an expected delivery date between May 1, 2021, and September 2, 2022, were included. Data were analyzed from January 2023 through March 2023. Exposure: Maternal mRNA COVID-19 vaccination (1 or more doses) during pregnancy. Main outcomes and measures: Severe neonatal morbidity (SNM), neonatal death, neonatal intensive care unit (NICU) admission, neonatal readmission, and hospital admission up to 6 months of age. The study team calculated inverse probability of treatment weighted risk ratios (RRs) and fit weighted Cox proportional hazards regression models comparing outcomes in infants of mothers who received COVID-19 vaccination during pregnancy with those who received no COVID-19 vaccine doses before delivery. Results: In total, 142 006 infants (72 595 male [51%]; mean [SD] gestational age at birth, 38.7 [1.7] weeks) were included; 85 670 were exposed to 1 or more COVID-19 vaccine doses in utero (60%). Infants of vaccinated mothers had lower risks of SNM (vaccine exposed 7.3% vs vaccine unexposed 8.3%; adjusted RR [aRR], 0.86; 95% CI, 0.83-0.90), neonatal death (0.09% vs 0.16%; aRR, 0.47; 95% CI, 0.33-0.65), and NICU admission (11.4% vs 13.1%; aRR, 0.86; 95% CI, 0.83-0.89). There was no association between maternal vaccination during pregnancy and neonatal readmission (5.5% vs 5.1%; adjusted hazard ratio, 1.03; 95% CI, 0.98-1.09) or 6-month hospital admission (8.4% vs 8.1%; adjusted hazard ratio, 1.01; 95% CI, 0.96-1.05). Conclusions and relevance: In this population-based cohort study in Ontario, Canada, maternal mRNA COVID-19 vaccination during pregnancy was associated with lower risks of SNM, neonatal death, and NICU admission. In addition, neonatal and 6-month readmissions were not increased in infants of mothers vaccinated during pregnancy.
    • Novel multiplex assay platforms to detect influenza A hemagglutinin subtype‐specific antibody responses for high‐throughput and in‐field applications

      Li, Zhu‐Nan; Trost, Jessica F.; Weber, Kimberly M.; LeMasters, Elizabeth H.; Nasreen, Sharifa; Esfandiari, Javan; Gunasekera, Angelo H.; McCausland, Megan; Sturm‐Ramirez, Katharine; Wrammert, Jens; et al. (Wiley, 2017-04-05)
      Background: Detections of influenza A subtype-specific antibody responses are often complicated by the presence of cross-reactive antibodies. We developed two novel multiplex platforms for antibody detection. The multiplexed magnetic fluorescence microsphere immunoassay (MAGPIX) is a high-throughput laboratory-based assay. Chembio Dual Path Platform (DPP) is a portable and rapid test that could be used in the field. Methods: Twelve recombinant globular head domain hemagglutinin (GH HA1) antigens from A(H1N1)pdm09 (pH1N1), A(H2N2), A(H3N2), A(H5N1), A(H7N9), A(H9N2), A(H13N9), B/Victoria lineage, B/Yamagata lineage viruses, and protein A control were used. Human sera from U.S. residents either vaccinated (with H5N1 or pH1N1) or infected with pH1N1 influenza viruses and sera from live bird market workers in Bangladesh (BDPW) were evaluated. GH HA1 antigens and serum adsorption using full ectodomain recombinant hemagglutinins from A(pH1N1) and A(H3N2) were introduced into the platforms to reduce cross-reactivity. Results: Serum adsorption reduced cross-reactivity to novel subtype HAs. Compared to traditional hemagglutination inhibition or microneutralization assays, when serum adsorption and the highest fold rise in signals were used to determine positivity, the correct subtype-specific responses were identified in 86%-100% of U.S. residents exposed to influenza antigens through vaccination or infection (N=49). For detection of H5N1-specific antibodies in sera collected from BDPW, H5 sensitivity was 100% (six of six) for MAGPIX, 83% (five of six) for DPP, H5 specificity was 100% (15/15), and cross-reactivity against other subtype was 0% (zero of six) for both platforms. Conclusion: MAGPIX and DPP platforms can be utilized for high-throughput and in-field detection of novel influenza virus infections.
    • Understanding community perceptions, social norms and current practice related to respiratory infection in Bangladesh during 2009: a qualitative formative study

      Nizame, Fosiul A; Nasreen, Sharifa; Unicomb, Leanne; Southern, Dorothy; Gurley, Emily S; Arman, Shaila; Kadir, Mohammad A; Azziz-Baumgartner, Eduardo; Luby, Stephen P; Winch, Peter J (Springer Science and Business Media LLC, 2011-12-04)
      Background: Respiratory infections are the leading cause of childhood deaths in Bangladesh. Promoting respiratory hygiene may reduce infection transmission. This formative research explored community perceptions about respiratory infections. Methods: We conducted 34 in-depth interviews and 16 focus group discussions with community members and school children to explore respiratory hygiene related perceptions, practices, and social norms in an urban and a rural setting. We conducted unstructured observations on respiratory hygiene practices in public markets. Results: Informants were not familiar with the term "respiratory infection"; most named diseases that had no relation to respiratory dysfunction. Informants reported that their community identified a number of 'good behaviors' related to respiratory hygiene, but they also noted, and we observed, that very few people practiced these. All informants cited hot/cold weather changes or using cold water as causes for catching cold. They associated transmission of respiratory infections with close contact with a sick person's breath, cough droplets, or spit; sharing a sick person's utensils and food. Informants suggested that avoiding such contact was the most effective method to prevent respiratory infection. Although informants perceived that handwashing after coughing or sneezing might prevent illness, they felt this was not typically feasible or practical. Conclusion: Community perceptions of respiratory infections include both concerns with imbalances between hot and cold, and with person-to-person transmission. Many people were aware of measures that could prevent respiratory infection, but did not practice them. Interventions that leverage community understanding of person-to-person transmission and that encourage the practice of their identified 'good behaviors' related to respiratory hygiene may reduce respiratory disease transmission.
    • Early Detection of Pandemic (H1N1) 2009, Bangladesh

      Azziz-Baumgartner, Eduardo; Rahman, Mustafizur; Al Mamun, Abdullah; Haider, Mohammad Sabbir; Zaman, Rashid Uz; Karmakar, Polash Chandra; Nasreen, Sharifa; Muneer, Syeda Mah-E; Homaira, Nusrat; Goswami, Doli Rani; et al. (Centers for Disease Control and Prevention (CDC), 2012-01)
      To explore Bangladesh's ability to detect novel influenza, we examined a series of laboratory-confirmed pandemic (H1N1) 2009 cases. During June-July 2009, event-based surveillance identified 30 case-patients (57% travelers); starting July 29, sentinel sites identified 252 case-patients (1% travelers). Surveillance facilitated response weeks before the spread of pandemic (H1N1) 2009 infection to the general population.
    • Impact of an Intensive Perinatal Handwashing Promotion Intervention on Maternal Handwashing Behavior in the Neonatal Period: Findings from a Randomized Controlled Trial in Rural Bangladesh

      Ram, Pavani Kalluri; Nasreen, Sharifa; Kamm, Kelly; Allen, Jelena; Kumar, Swapna; Rahman, Mohammad Anisur; Zaman, K.; El Arifeen, Shams; Luby, Stephen P. (Hindawi Limited, 2017)
      One-quarter of neonatal deaths are attributed to infections. Maternal handwashing with soap may prevent neonatal sepsis. We examined impact of intensive handwashing promotion on handwashing behavior of mothers of neonates. In Matlab, Bangladesh, we randomly allocated pregnant women at 28-32 weeks' gestation to intensive handwashing promotion or control. Behavior change communicators used a participatory approach to motivate maternal handwashing with soap and provided soap and handwashing stations. In the neonatal period, we observed soap and water at handwashing places and, at the end of the neonatal period, we estimated impact on maternal handwashing by structured observation. Among 253 women enrolled, intervention households were between 5.7 and 15.2 times as likely as control households to have soap and water present at the handwashing station in the baby's sleeping area. Intervention mothers washed hands with soap 4.1 times as frequently as controls (95% CI 2.55-6.59); handwashing with soap at recommended times was infrequent in both intervention (9%) and control (2%) groups. Intensively promoting handwashing with soap resulted in increased availability of soap and water at handwashing places, but only a modest increase in maternal handwashing with soap. Novel approaches to motivating handwashing behavior to protect newborns should be developed and evaluated.
    • Maternal mRNA covid-19 vaccination during pregnancy and delta or omicron infection or hospital admission in infants: test negative design study

      Jorgensen, Sarah C J; Hernandez, Alejandro; Fell, Deshayne B; Austin, Peter C; D’Souza, Rohan; Guttmann, Astrid; Brown, Kevin A; Buchan, Sarah A; Gubbay, Jonathan B; Nasreen, Sharifa; et al. (BMJ, 2023-02-08)
      Objective: To estimate the effectiveness of maternal mRNA covid-19 vaccination during pregnancy against delta and omicron severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection and hospital admission in infants. Design: Test negative design study. Setting: Community and hospital testing in Ontario, Canada. Participants: Infants younger than six months of age, born between 7 May 2021 and 31 March 2022, who were tested for SARS-CoV-2 between 7 May 2021 and 5 September 2022. Intervention: Maternal mRNA covid-19 vaccination during pregnancy. Main outcome measures: Laboratory confirmed delta or omicron infection or hospital admission of the infant. Multivariable logistic regression estimated vaccine effectiveness, with adjustments for clinical and sociodemographic characteristics associated with vaccination and infection. Results: 8809 infants met eligibility criteria, including 99 delta cases (4365 controls) and 1501 omicron cases (4847 controls). Infant vaccine effectiveness from two maternal doses was 95% (95% confidence interval 88% to 98%) against delta infection and 97% (73% to 100%) against infant hospital admission due to delta and 45% (37% to 53%) against omicron infection and 53% (39% to 64%) against hospital admission due to omicron. Vaccine effectiveness for three doses was 73% (61% to 80%) against omicron infection and 80% (64% to 89%) against hospital admission due to omicron. Vaccine effectiveness for two doses against infant omicron infection was highest with the second dose in the third trimester (53% (42% to 62%)) compared with the first (47% (31% to 59%)) or second (37% (24% to 47%)) trimesters. Vaccine effectiveness for two doses against infant omicron infection decreased from 57% (44% to 66%) between birth and eight weeks to 40% (21% to 54%) after 16 weeks of age. Conclusions: Maternal covid-19 vaccination with a second dose during pregnancy was highly effective against delta and moderately effective against omicron infection and hospital admission in infants during the first six months of life. A third vaccine dose bolstered protection against omicron. Effectiveness for two doses was highest with maternal vaccination in the third trimester, and effectiveness decreased in infants beyond eight weeks of age.
    • Effectiveness of mRNA COVID-19 vaccine booster doses against Omicron severe outcomes

      Grewal, Ramandip; Nguyen, Lena; Buchan, Sarah A.; Wilson, Sarah E.; Nasreen, Sharifa; Austin, Peter C.; Brown, Kevin A.; Fell, Deshayne B.; Gubbay, Jonathan B.; Schwartz, Kevin L.; et al. (Springer Science and Business Media LLC, 2023-03-07)
      We estimated the effectiveness of booster doses of monovalent mRNA COVID-19 vaccines against Omicron-associated severe outcomes among adults in Ontario, Canada. We used a test-negative design to estimate vaccine effectiveness (VE) against hospitalization or death among SARS-CoV-2-tested adults aged ≥50 years from January 2 to October 1, 2022, stratified by age and time since vaccination. We also compared VE during BA.1/BA.2 and BA.4/BA.5 sublineage predominance. We included 11,160 cases and 62,880 tests for test-negative controls. Depending on the age group, compared to unvaccinated adults, VE was 91–98% 7–59 days after a third dose, waned to 76–87% after ≥240 days, was restored to 92–97% 7–59 days after a fourth dose, and waned to 86–89% after ≥120 days. VE was lower and declined faster during BA.4/BA.5 versus BA.1/BA.2 predominance, particularly after ≥120 days. Here we show that booster doses of monovalent mRNA COVID-19 vaccines restored strong protection against severe outcomes for at least 3 months after vaccination. Across the entire study period, protection declined slightly over time, but waned more during BA.4/BA.5 predominance.
    • Barriers to and motivators of handwashing behavior among mothers of neonates in rural Bangladesh

      Parveen, Shahana; Nasreen, Sharifa; Allen, Jelena V.; Kamm, Kelly B.; Khan, Shifat; Akter, Shirina; Lopa, Tajnin Marin; Zaman, K.; El Arifeen, Shams; Luby, Stephen P.; et al. (Springer Science and Business Media LLC, 2018-04-11)
      Background: To design a maternal handwashing intervention for the newborn period, this qualitative study explored drivers of handwashing among mothers and other caregivers of neonates and infants in two rural areas of Bangladesh. Methods: We conducted 40 semi-structured observation sessions to observe handwashing behaviors of primiparous and multiparous mothers of neonates, and to understand the contextual factors that facilitated or hampered those behaviors. We then conducted 64 interviews with mothers of neonates and mothers of infants and 6 group discussions with mothers of infants, other female caregivers and fathers to explore perceptions, beliefs, and practices related to handwashing in the neonatal period. Based on a conceptual model and the Theory of Reasoned Action/Theory of Planned Behavior, we developed a conceptual model a priori, we performed thematic analysis to explain determinants of maternal handwashing behaviors. Results: We conducted 200 h of observation among mothers of neonates. The age range of participating mothers varied between 17 and 25 years and their maximum education was up to 10th grade of schooling. Mothers, other female caregivers and fathers perceived a need to wash hands with or without soap before eating or before feeding a child by hand to prevent diarrhea. Mothers expressed the importance of washing their hands before holding a baby but were rarely observed doing so. All respondents prioritized using soap for visible dirt or feces; otherwise, water alone was considered sufficient. Lack of family support, social norms of infrequent handwashing, perceptions of frequent contact with water as a health threat and mothers' restricted movement during first 40 days of neonate's life, and childcare and household responsibilities adversely impacted handwashing behavior. Conclusions: Addressing emotive drivers of handwashing within existing social norms by engaging family members, ensuring handwashing facilities and clarifying neonatal health threats may improve maternal handwashing behavior in the neonatal period.
    • Seroprevalence of Antibodies against Highly Pathogenic Avian Influenza A (H5N1) Virus among Poultry Workers in Bangladesh, 2009

      Nasreen, Sharifa; Uddin Khan, Salah; Azziz-Baumgartner, Eduardo; Hancock, Kathy; Veguilla, Vic; Wang, David; Rahman, Mahmudur; Alamgir, A. S. M.; Sturm-Ramirez, Katharine; Gurley, Emily S.; et al. (Public Library of Science (PLoS), 2013-09-05)
      We conducted a cross-sectional study in 2009 to determine the seroprevalence and risk factors for highly pathogenic avian influenza A (H5N1) [HPAI H5N1] virus antibodies among poultry workers at farms and live bird markets with confirmed/suspected poultry outbreaks during 2009 in Bangladesh. We tested sera by microneutralization assay using A/Bangladesh/207095/2008 (H5N1; clade 2.2.2) virus with confirmation by horse red blood cell hemagglutination inhibition and H5-specific Western blot assays. We enrolled 212 workers from 87 farms and 210 workers from three live bird markets. One hundred and two farm workers (48%) culled poultry. One hundred and ninety-three farm workers (91%) and 178 market workers (85%) reported direct contact with poultry that died during a laboratory confirmed HPAI H5N1 poultry farm outbreak or market poultry die-offs from suspected HPAI H5N1. Despite exposure to sick poultry, no farm or market poultry workers were seropositive for HPAI H5N1 virus antibodies (95% confidence interval 0-1%).
    • Observed Practices and Perceived Advantages of Different Hand Cleansing Agents in Rural Bangladesh: Ash, Soil, and Soap

      Nizame, Fosiul A.; Unicomb, Leanne; Luby, Stephen P.; Arman, Shaila; Winch, Peter J.; Nasreen, Sharifa; Halder, Amal K. (American Society of Tropical Medicine and Hygiene, 2015-06-03)
      Bangladeshi communities have historically used ash and soil as handwashing agents. A structured observation study and qualitative interviews on the use of ash/soil and soap as handwashing agents were conducted in rural Bangladesh to help develop a handwashing promotion intervention. The observations were conducted among 1,000 randomly selected households from 36 districts. Fieldworkers observed people using ash/soil to wash their hand(s) on 13% of occasions after defecation and on 10% after cleaning a child's anus. This compares with 19% of people who used soap after defecation and 27% after cleaning a child who defecated. Using ash/soil or soap was rarely (< 1%) observed at other times recommended for handwashing. The qualitative study enrolled 24 households from three observation villages, where high usage of ash/soil for handwashing was detected. Most informants reported that ash/soil was used only for handwashing after fecal contact, and that ash/soil could clean hands as effectively as soap.
    • Prevalent high-risk respiratory hygiene practices in urban and rural Bangladesh

      Nasreen, S.; Azziz-Baumgartner, E.; Gurley, E. S.; Winch, P. J.; Unicomb, L.; Sharker, M. A. Y.; Southern, D.; Luby, S. P. (Wiley, 2010-03-30)
      Objectives: To identify existing respiratory hygiene risk practices, and guide the development of interventions for improving respiratory hygiene. Methods: We selected a convenience sample of 80 households and 20 schools in two densely populated communities in Bangladesh, one urban and one rural. We observed and recorded respiratory hygiene events with potential to spread viruses such as coughing, sneezing, spitting and nasal cleaning using a standardized assessment tool. Results: In 907 (81%) of 1122 observed events, households' participants coughed or sneezed into the air (i.e. uncovered), 119 (11%) into their hands and 83 (7%) into their clothing. Twenty-two per cent of women covered their coughs and sneezes compared to 13% of men (OR 2.6, 95% CI 1.6-4.3). Twenty-seven per cent of persons living in households with a reported monthly income of >72.6 US$ covered their coughs or sneezes compared to 13% of persons living in households with lower income (OR 3.2, 95% CI 1.6-6.2). In 956 (85%) of 1126 events, school participants coughed or sneezed into the air and 142 (13%) into their hands. Twenty-seven per cent of coughs/sneezes in rural schools were covered compared to 10% of coughs/sneezes in urban schools (OR 2.3, 95% CI 1.5-3.6). Hand washing was never observed after participants coughed or sneezed into their hands. Conclusion: There is an urgent need to develop culturally appropriate, cost-effective and scalable interventions to improve respiratory hygiene practices and to assess their effectiveness in reducing respiratory pathogen transmission.