Last data update: Jun 03, 2024. (Total: 46935 publications since 2009)
Records 1-30 (of 35 Records) |
Query Trace: Hajjeh R [original query] |
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A pediatric HIV outbreak in Pakistan
Hermez J , Ismail M , Morgan O , Pasha MS , Schenkel K , Doherty M , Tayyab M , Abdella YE , Sayed MA , Memon NM , Asghar RJ , Rahim M , Sheikh S , Ali H , Rabold EM , Fontaine R , Hutin Y , Hajjeh R . East Mediterr Health J 2024 30 (1) 60-67 Background: Following reports of an outbreak of HIV infection among children in Larkana District, Pakistan, an international team investigated the extent and cause of the outbreak between April and June 2019. Aims: To investigate the incidence of HIV among children in Larkana District, Pakistan and describe the distribution of cases by time, place and person. |
MenAfriNet: A network supporting case-based meningitis surveillance and vaccine evaluation in the meningitis belt of Africa
Patel JC , Soeters HM , Diallo AO , Bicaba BW , Kadade G , Dembele AY , Acyl MA , Nikiema C , Lingani C , Hatcher C , Acosta AM , Thomas JD , Diomande F , Martin S , Clark TA , Mihigo R , Hajjeh RA , Zilber CH , Ake F , Mbaeyi SA , Wang X , Moisi JC , Ronveaux O , Mwenda JM , Novak RT . J Infect Dis 2019 220 S148-s154 Meningococcal meningitis remains a significant public health threat, especially in the African meningitis belt where Neisseria meningitidis serogroup A historically caused large-scale epidemics. With the rollout of a novel meningococcal serogroup A conjugate vaccine (MACV) in the belt, the World Health Organization recommended case-based meningitis surveillance to monitor MACV impact and meningitis epidemiology. In 2014, the MenAfriNet consortium was established to support strategic implementation of case-based meningitis surveillance in 5 key countries: Burkina Faso, Chad, Mali, Niger, and Togo. MenAfriNet aimed to develop a high-quality surveillance network using standardized laboratory and data collection protocols, develop sustainable systems for data management and analysis to monitor MACV impact, and leverage the surveillance platform to perform special studies. We describe the MenAfriNet consortium, its history, strategy, implementation, accomplishments, and challenges. |
Perceptions and acceptability of an experimental Ebola vaccine among health care workers, frontline staff, and the general public during the 2014-2015 Ebola outbreak in Sierra Leone
Jalloh MF , Jalloh MB , Albert A , Wolff B , Callis A , Ramakrishnan A , Cramer E , Sengeh P , Pratt SA , Conteh L , Hajjeh R , Bunnell R , Redd JT , Ekstrom AM , Nordenstedt H . Vaccine 2019 37 (11) 1495-1502 INTRODUCTION: Experimental Ebola vaccines were introduced during the 2014-2015 Ebola outbreak in West Africa. Planning for the Sierra Leone Trial to Introduce a Vaccine against Ebola (STRIVE) was underway in late 2014. We examined hypothetical acceptability and perceptions of experimental Ebola vaccines among health care workers (HCWs), frontline workers, and the general public to guide ethical communication of risks and benefits of any experimental Ebola vaccine. METHODS: Between December 2014 and January 2015, we conducted in-depth interviews with public health leaders (N=31), focus groups with HCWs and frontline workers (N=20), and focus groups with members of the general public (N=15) in Western Area Urban, Western Area Rural, Port Loko, Bombali, and Tonkolili districts. Themes were identified using qualitative content analysis. RESULTS: Across all participant groups, not knowing the immediate and long-term effects of an experimental Ebola vaccine was the most serious concern. Some respondents feared that experimental vaccines may cause Ebola, lead to death, or result in other adverse events. Among HCWs, not knowing the level of protection provided by experimental Ebola vaccines was another concern. HCWs and frontline workers were motivated to help find a vaccine for Ebola to help end the outbreak. General public participants cited positive experiences with routine childhood immunization in Sierra Leone. DISCUSSION: Our formative assessment prior to STRIVE's implementation in Sierra Leone helped identify concerns, motivations, and information gaps among potential participants of an experimental Ebola vaccine trial, at the time when an unprecedented outbreak was occurring in the country. The findings from this assessment were incorporated early in the process to guide ethical communication of risks and benefits when discussing informed consent for possible participation in the vaccine trial that was launched later in 2015. |
Progress in vaccine-preventable and respiratory infectious diseases - first 10 Years of the CDC National Center for Immunization and Respiratory Diseases, 2006-2015
Schuchat A , Anderson LJ , Rodewald LE , Cox NJ , Hajjeh R , Pallansch MA , Messonnier NE , Jernigan DB , Wharton M . Emerg Infect Dis 2018 24 (7) 1178-1187 The need for closer linkages between scientific and programmatic areas focused on addressing vaccine-preventable and acute respiratory infections led to establishment of the National Center for Immunization and Respiratory Diseases (NCIRD) at the Centers for Disease Control and Prevention. During its first 10 years (2006-2015), NCIRD worked with partners to improve preparedness and response to pandemic influenza and other emergent respiratory infections, provide an evidence base for addition of 7 newly recommended vaccines, and modernize vaccine distribution. Clinical tools were developed for improved conversations with parents, which helped sustain childhood immunization as a social norm. Coverage increased for vaccines to protect adolescents against pertussis, meningococcal meningitis, and human papillomavirus-associated cancers. NCIRD programs supported outbreak response for new respiratory pathogens and oversaw response of the Centers for Disease Control and Prevention to the 2009 influenza A(H1N1) pandemic. Other national public health institutes might also find closer linkages between epidemiology, laboratory, and immunization programs useful. |
Attitudes about vaccines to prevent Ebola virus disease in Guinea at the end of a large Ebola epidemic: Results of a national household survey
Irwin KL , Jalloh MF , Corker J , Alpha Mahmoud B , Robinson SJ , Li W , James NE , Sellu M , Jalloh MB , Diallo AA , Tracy L , Hajjeh R , VanSteelandt A , Bunnell R , Martel L , Raghunathan PL , Marston B . Vaccine 2017 35 6915-6923 INTRODUCTION: In 2014-2016, an Ebola epidemic devastated Guinea; more than 3800 cases and 2500 deaths were reported to the World Health Organization. In August 2015, as the epidemic waned and clinical trials of an experimental, Ebola vaccine continued in Guinea and neighboring Sierra Leone, we conducted a national household survey about Ebola-related knowledge, attitudes, and practices (KAP) and opinions about "hypothetical" Ebola vaccines. METHODS: Using cluster-randomized sampling, we selected participants aged 15+ years old in Guinea's 8 administrative regions, which had varied cumulative case counts. The questionnaire assessed socio-demographic characteristics, experiences during the epidemic, Ebola-related KAP, and Ebola vaccine attitudes. To assess the potential for Ebola vaccine introduction in Guinea, we examined the association between vaccine attitudes and participants' characteristics using categorical and multivariable analyses. RESULTS: Of 6699 persons invited to participate, 94% responded to at least 1 Ebola vaccine question. Most agreed that vaccines were needed to fight the epidemic (85.8%) and that their family would accept safe, effective Ebola vaccines if they became available in Guinea (84.2%). These measures of interest and acceptability were significantly more common among participants who were male, wealthier, more educated, and lived with young children who had received routine vaccines. Interest and acceptability were also significantly higher among participants who understood Ebola transmission modes, had witnessed Ebola response teams, knew Ebola-affected persons, believed Ebola was not always fatal, and would access Ebola treatment centers. In multivariable analyses of the majority of participants living with young children, interest and acceptability were significantly higher among those living with vaccinated children than among those living with unvaccinated children. DISCUSSION: The high acceptability of hypothetical vaccines indicates strong potential for introducing Ebola vaccines across Guinea. Strategies to build public confidence in use of Ebola vaccines should highlight any similarities with safe, effective vaccines routinely used in Guinea. |
Case-control vaccine effectiveness studies: Data collection, analysis and reporting results
Verani JR , Baqui AH , Broome CV , Cherian T , Cohen C , Farrar JL , Feikin DR , Groome MJ , Hajjeh RA , Johnson HL , Madhi SA , Mulholland K , O'Brien KL , Parashar UD , Patel MM , Rodrigues LC , Santosham M , Scott JA , Smith PG , Sommerfelt H , Tate JE , Victor JC , Whitney CG , Zaidi AK , Zell ER . Vaccine 2017 35 (25) 3303-3308 The case-control methodology is frequently used to evaluate vaccine effectiveness post-licensure. The results of such studies provide important insight into the level of protection afforded by vaccines in a 'real world' context, and are commonly used to guide vaccine policy decisions. However, the potential for bias and confounding are important limitations to this method, and the results of a poorly conducted or incorrectly interpreted case-control study can mislead policies. In 2012, a group of experts met to review recent experience with case-control studies evaluating vaccine effectiveness; we summarize the recommendations of that group regarding best practices for data collection, analysis, and presentation of the results of case-control vaccine effectiveness studies. Vaccination status is the primary exposure of interest, but can be challenging to assess accurately and with minimal bias. Investigators should understand factors associated with vaccination as well as the availability of documented vaccination status in the study context; case-control studies may not be a valid method for evaluating vaccine effectiveness in settings where many children lack a documented immunization history. To avoid bias, it is essential to use the same methods and effort gathering vaccination data from cases and controls. Variables that may confound the association between illness and vaccination are also important to capture as completely as possible, and where relevant, adjust for in the analysis according to the analytic plan. In presenting results from case-control vaccine effectiveness studies, investigators should describe enrollment among eligible cases and controls as well as the proportion with no documented vaccine history. Emphasis should be placed on confidence intervals, rather than point estimates, of vaccine effectiveness. Case-control studies are a useful approach for evaluating vaccine effectiveness; however careful attention must be paid to the collection, analysis and presentation of the data in order to best inform evidence-based vaccine policies. |
Case-control vaccine effectiveness studies: Preparation, design, and enrollment of cases and controls
Verani JR , Baqui AH , Broome CV , Cherian T , Cohen C , Farrar JL , Feikin DR , Groome MJ , Hajjeh RA , Johnson HL , Madhi SA , Mulholland K , O'Brien KL , Parashar UD , Patel MM , Rodrigues LC , Santosham M , Scott JA , Smith PG , Sommerfelt H , Tate JE , Victor JC , Whitney CG , Zaidi AK , Zell ER . Vaccine 2017 35 (25) 3295-3302 Case-control studies are commonly used to evaluate effectiveness of licensed vaccines after deployment in public health programs. Such studies can provide policy-relevant data on vaccine performance under 'real world' conditions, contributing to the evidence base to support and sustain introduction of new vaccines. However, case-control studies do not measure the impact of vaccine introduction on disease at a population level, and are subject to bias and confounding, which may lead to inaccurate results that can misinform policy decisions. In 2012, a group of experts met to review recent experience with case-control studies evaluating the effectiveness of several vaccines; here we summarize the recommendations of that group regarding best practices for planning, design and enrollment of cases and controls. Rigorous planning and preparation should focus on understanding the study context including healthcare-seeking and vaccination practices. Case-control vaccine effectiveness studies are best carried out soon after vaccine introduction because high coverage creates strong potential for confounding. Endpoints specific to the vaccine target are preferable to non-specific clinical syndromes since the proportion of non-specific outcomes preventable through vaccination may vary over time and place, leading to potentially confusing results. Controls should be representative of the source population from which cases arise, and are generally recruited from the community or health facilities where cases are enrolled. Matching of controls to cases for potential confounding factors is commonly used, although should be reserved for a limited number of key variables believed to be linked to both vaccination and disease. Case-control vaccine effectiveness studies can provide information useful to guide policy decisions and vaccine development, however rigorous preparation and design is essential. |
The 17th International Congress on Infectious Diseases Workshop on Developing Infection Prevention and Control Resources for Low to Middle Income Countries
Sastry S , Masroor N , Bearman G , Hajjeh R , Holmes A , Memish Z , Lassmann B , Pittet D , Macnab F , Kamau R , Wesangula E , Pokharel P , Brown P , Daily F , Amer F , Torres J , O'Ryan M , Gunturu R , Bulabula A , Mehtar S . Int J Infect Dis 2017 57 138-143 Hospital acquired infections (HAIs) are a major concern to healthcare systems around the world. They are associated with significant morbidity and mortality, in addition to increased hospitalization costs. Recent outbreaks including MERS (Middle East Respiratory Syndrome) coronavirus and Ebola have highlighted the importance of infection control. Further, HAIs especially with multi-drug resistant gram negative rods (MDRO-GNRs) have become a top global priority. Though adequate approaches and guidelines have been in existence for many years and have sometimes proven effective in some countries, the implementation of such approaches in low and middle income countries (LMICs) is often restricted due to limited resources and underdeveloped infrastructure. While evidence based infection control principles and practices are universal, studies are needed to evaluate simplified approaches that can be better adapted to LMIC needs, in order to practically guide IPC practices. A group of experts from around the world attended a workshop held at the 17th International Congress on Infectious Diseases conference in Hyderabad, India, to discuss the existing IPC practices in LMICs, and how these can be best improved within the local context. |
Pneumonia prevention: Cost-effectiveness analyses of two vaccines among refugee children aged under two years, Haemophilus influenzae type b-containing and pneumococcal conjugate vaccines, during a humanitarian emergency, Yida camp, South Sudan
Gargano LM , Hajjeh R , Cookson ST . Vaccine 2017 35 (3) 435-442 By September 2013, war between Sudan and South Sudan resulted in >70,000 Sudanese refugees and high pneumonia incidence among the 20,000 refugees in Yida camp, South Sudan. Using Medecins Sans Frontieres (MSF)-provided data and modifying our decision-tree models, we estimated if administering Haemophilus influenzae type b (Hib)-containing (pentavalent vaccine, also with diphtheria pertussis and tetanus [DPT] and hepatitis B) and pneumococcal conjugate (PCV) vaccines were cost-effective against hospitalized pneumonia. Among children < 2 years old, compared with no vaccination, one- and two-doses of combined Hib-containing and PCV would avert an estimated 118 and 125 pneumonia cases, and 8.5 and 9.1 deaths, respectively. The cost per Disability-Adjusted-Life-Year averted for administering combined one- and two-doses was US$125 and US$209, respectively. MSF demonstrated that it was possible to administer these vaccines during an emergency and our analysis found it was highly cost-effective, even with just one-dose of either vaccine. Despite unknown etiology, there is strong field and now economic rationale for administering Hib and PCV during at least one humanitarian emergency. |
Secondary infections with Ebola virus in rural communities, Liberia and Guinea, 2014-2015
Lindblade KA , Nyenswah T , Keita S , Diallo B , Kateh F , Amoah A , Nagbe TK , Raghunathan P , Neatherlin JC , Kinzer M , Pillai SK , Attfield KR , Hajjeh R , Dweh E , Painter J , Barradas DT , Williams SG , Blackley DJ , Kirking HL , Patel MR , Dea M , Massoudi MS , Barskey AE , Zarecki SL , Fomba M , Grube S , Belcher L , Broyles LN , Maxwell TN , Hagan JE , Yeoman K , Westercamp M , Mott J , Mahoney F , Slutsker L , DeCock KM , Marston B , Dahl B . Emerg Infect Dis 2016 22 (9) 1653-5 Persons who died of Ebola virus disease at home in rural communities in Liberia and Guinea resulted in more secondary infections than persons admitted to Ebola treatment units. Intensified monitoring of contacts of persons who died of this disease in the community is an evidence-based approach to reduce virus transmission in rural communities. |
Risk factors for primary Middle East respiratory syndrome coronavirus illness in humans, Saudi Arabia, 2014
Alraddadi BM , Watson JT , Almarashi A , Abedi GR , Turkistani A , Sadran M , Housa A , Almazroa MA , Alraihan N , Banjar A , Albalawi E , Alhindi H , Choudhry AJ , Meiman JG , Paczkowski M , Curns A , Mounts A , Feikin DR , Marano N , Swerdlow DL , Gerber SI , Hajjeh R , Madani TA . Emerg Infect Dis 2016 22 (1) 49-55 Risk factors for primary Middle East respiratory syndrome coronavirus (MERS-CoV) illness in humans are incompletely understood. We identified all primary MERS-CoV cases reported in Saudi Arabia during March-November 2014 by excluding those with history of exposure to other cases of MERS-CoV or acute respiratory illness of unknown cause or exposure to healthcare settings within 14 days before illness onset. Using a case-control design, we assessed differences in underlying medical conditions and environmental exposures among primary case-patients and 2-4 controls matched by age, sex, and neighborhood. Using multivariable analysis, we found that direct exposure to dromedary camels during the 2 weeks before illness onset, as well as diabetes mellitus, heart disease, and smoking, were each independently associated with MERS-CoV illness. Further investigation is needed to better understand animal-to-human transmission of MERS-CoV. |
Pneumonia prevention during a humanitarian emergency: cost-effectiveness of haemophilus influenzae type B conjugate vaccine and pneumococcal conjugate vaccine in Somalia
Gargano LM , Hajjeh R , Cookson ST . Prehosp Disaster Med 2015 30 (4) 1-10 BACKGROUND: Pneumonia is a leading cause of death among children less than five years old during humanitarian emergencies. Haemophilus influenzae type b (Hib) and Streptococcus pneumoniae are the leading causes of bacterial pneumonia. Vaccines for both of these pathogens are available to prevent pneumonia. PROBLEM: This study describes an economic analysis from a publicly funded health care system perspective performed on a birth cohort in Somalia, a country that has experienced a protracted humanitarian emergency. METHODS: An impact and cost-effectiveness analysis was performed comparing: no vaccine, Hib vaccine only, pneumococcal conjugate vaccine 10 (PCV10) only, and both together administered through supplemental immunization activities (SIAs). The main summary measure was the incremental cost per disability-adjusted life-years (DALYs) averted. One-way sensitivity analysis was conducted for uncertainty in parameter values. RESULTS: Each SIA would avert a substantial number of cases and deaths. Compared with no vaccine, the DALYs averted by two SIAs for two doses of Hib vaccine was US $202.93 (lower and upper limits: $121.80-$623.52), two doses of PCV10 was US $161.51 ($107.24-$227.21), and two doses of both vaccines was US $152.42 ($101.20-$214.42). Variables that influenced the cost-effectiveness for each strategy most substantially were vaccine effectiveness, case fatality rates (CFRs), and disease burden. CONCLUSIONS: The World Health Organization (WHO) defines a cost-effective intervention as costing one to three times the per capita gross domestic product (GDP; in 2011, for Somalia=US $112). Based on the presented model, Hib vaccine alone, PCV10 alone, or Hib vaccine and PCV10 given together in SIAs are cost-effective interventions in Somalia. The WHO/Strategic Advisory Group of Experts decision-making factors for vaccine deployment appear to have all been met: the disease burden is large, the vaccine-related risk is low, prevention in this setting is more feasible than treatment, the vaccine duration probably is sufficient for the vulnerable period of the child's life, cost is reasonable, and herd immunity is possible. |
Evidence-based decision-making for vaccine introductions: overview of the ProVac International Working Group's experience
Jauregui B , Garcia AG , Bess Janusz C , Blau J , Munier A , Atherly D , Mvundura M , Hajjeh R , Lopman B , Clark AD , Baxter L , Hutubessy R , de Quadros C , Andrus JK . Vaccine 2015 33 Suppl 1 A28-33 INTRODUCTION: Pan American Health Organization's (PAHO) ProVac Initiative aims to strengthen countries' technical capacity to make evidence-based immunization policy. With financial support from the Bill and Melinda Gates Foundation, PAHO established the ProVac International Working Group (IWG), a platform created for two years to transfer the ProVac Initiative's tools and methods to support decisions in non-PAHO regions. METHODS: In 2011, WHO Regional Offices and partner agencies established the IWG to transfer the ProVac framework for new vaccine decision support, including tools and trainings to other regions of the world. During the two year period, PAHO served as the coordinating secretariat and partner agencies played implementing or advisory roles. RESULTS: Fifty nine national professionals from 17 countries received training on the use of economic evaluations to aid vaccine policy making through regional workshops. The IWG provided direct technical support to nine countries to develop cost-effectiveness analyses to inform decisions. All nine countries introduced the new vaccine evaluated or their NITAGs have made a recommendation to the Ministry of Health to introduce the new vaccine. DISCUSSION: Developing countries around the world are increasingly interested in weighing the potential health impact due to new vaccine introduction against the investments required. During the two years, the ProVac approach proved valuable and timely to aid the national decision making processes, even despite the different challenges and idiosyncrasies encountered in each region. The results of this work suggest that: (1) there is great need and demand for technical support and for capacity building around economic evaluations; and (2) the ProVac method of supporting country-owned analyses is as effective in other regions as it has been in the PAHO region. CONCLUSION: Decision support for new vaccine introduction in low- and middle-income countries is critical to guiding the efficient use of resources and prioritizing high impact vaccination programs. |
Cost-effectiveness analysis of the introduction of the pneumococcal conjugate vaccine (PCV-13) in the Egyptian national immunization program, 2013
Sibak M , Moussa I , El-Tantawy N , Badr S , Chaudhri I , Allam E , Baxter L , Abo Freikha S , Hoestlandt C , Lara C , Hajjeh R , Munier A . Vaccine 2015 33 Suppl 1 A182-91 INTRODUCTION: Pneumonia is one of the most important causes of morbidity and mortality in children under 5 in Egypt, and the Ministry of Health of Egypt is considering introducing pneumococcal conjugate vaccine (PCV) in its national immunization program. We performed an economic analysis to evaluate the cost-effectiveness of this vaccine in Egypt and to provide the decision-makers with needed evidence. METHODS: The analysis was done using the TRIVAC model. Data included demographic characteristics, burden of disease, coverage and efficacy of the vaccine, health resource utilization, and costs of pneumococcal disease vaccination and treatment. Whenever possible, we used national or regional data. Two alternatives were compared: (1) general vaccination of children younger than 5 years with the 13-valent pneumococcal conjugate vaccine (PCV13), using a three-dose schedule without booster, and (2) no vaccination. Outcomes of 10 cohorts from birth to 5 years were analyzed. The study was performed from the governmental perspective and selected public health providers. RESULTS: In comparison to no vaccine, the introduction of PCV13 would be cost-effective, with an incremental cost-effectiveness ratio of US$ 3916 per disability-adjusted life-year (DALY) averted (government perspective). The total incremental cost of the PCV vaccination program (10 cohorts) would be approximately US$ 1.09 billion. Over the 10 cohorts, the program would avert 8583 pneumococcal deaths - 42% of all pneumococcal-related deaths. CONCLUSION: The introduction of PCV13 would be a good value for money from the government perspective. It would represent a high-impact public health intervention for Egypt and respond to the National Immunization Technical Advisory Group (NITAG) resolution on reducing pneumonia burden and overall child mortality. Strengthening surveillance will be critical to generating high-quality national data, improving future economic analyses that support evidence-based decisions for introducing vaccines and public health interventions, and to monitoring their impact. |
Global invasive bacterial vaccine-preventable diseases surveillance - 2008-2014
Murray J , Agocs M , Serhan F , Singh S , Deloria-Knoll M , O'Brien K , Mwenda JM , Mihigo R , Oliveira L , Teleb N , Ahmed H , Wasley A , Videbaek D , Wijesinghe P , Thapa AB , Fox K , Paladin FJ , Hajjeh R , Schwartz S , Beneden CV , Hyde T , Broome C , Cherian T . MMWR Morb Mortal Wkly Rep 2014 63 (49) 1159-62 Meningitis and pneumonia are leading causes of morbidity and mortality in children globally infected with Streptococcus pneumoniae (pneumococcus), Neisseria meningitidis, and Haemophilus influenzae causing a large proportion of disease. Vaccines are available to prevent many of the common types of these infections. S. pneumoniae was estimated to have caused 11% of deaths in children aged <5 years globally in the pre-pneumococcal conjugate vaccine (PCV) era. Since 2007, the World Health Organization (WHO) has recommended inclusion of PCV in childhood immunization programs worldwide, especially in countries with high child mortality. As of November 26, 2014, a total of 112 (58%) of all 194 WHO member states and 44 (58%) of the 76 member states ever eligible for support from Gavi, the Vaccine Alliance (Gavi), have introduced PCV. Invasive pneumococcal disease (IPD) surveillance that includes data on serotypes, along with meningitis and pneumonia syndromic surveillance, provides important data to guide decisions to introduce PCV and monitor its impact. |
Cost-effectiveness of Haemophilus influenzae Type b conjugate vaccine in low- and middle-income countries: regional analysis and assessment of major determinants
Griffiths UK , Clark A , Hajjeh R . J Pediatr 2013 163 S50-S59 e9 OBJECTIVES: To estimate the cost-effectiveness of Haemophilus influenzae type b (Hib) conjugate vaccine in low- and middle-income countries and identify the model variables, which are most important for the result. STUDY DESIGN: A static decision tree model was developed to predict incremental costs and health impacts. Estimates were generated for 4 country groups: countries eligible for funding by the GAVI Alliance in Africa and Asia, lower middle-income countries, and upper middle-income countries. Values, including disease incidence, case fatality rates, and treatment costs, were based on international country estimates and the scientific literature. RESULTS: From the societal perspective, it is estimated that the probability of Hib conjugate vaccine cost saving is 34%-53% in Global Alliance for Vaccines and Immunization eligible African and Asian countries, respectively. In middle-income countries, costs per discounted disability adjusted life year averted are between US$37 and US$733. Variation in vaccine prices and risks of meningitis sequelae and mortality explain most of the difference in results. For all country groups, disease incidence cause the largest part of the uncertainty in the result. CONCLUSIONS: Hib conjugate vaccine is cost saving or highly cost-effective in low- and middle-income settings. This conclusion is especially influenced by the recent decline in Hib conjugate vaccine prices and new data revealing the high costs of lost productivity associated with meningitis sequelae. |
Impact and cost-effectiveness of Haemophilus influenzae type b conjugate vaccination in India
Clark AD , Griffiths UK , Abbas SS , Rao KD , Privor-Dumm L , Hajjeh R , Johnson H , Sanderson C , Santosham M . J Pediatr 2013 163 S60-72 OBJECTIVE: To estimate the potential health impact and cost-effectiveness of nationwide Haemophilus influenzae type b (Hib) vaccination in India. STUDY DESIGN: A decision support model was used, bringing together estimates of demography, epidemiology, Hib vaccine effectiveness, Hib vaccine costs, and health care costs. Scenarios favorable and unfavorable to the vaccine were evaluated. State-level analyses indicate where the vaccine might have the greatest impact and value. RESULTS: Between 2012 and 2031, Hib conjugate vaccination is estimated to prevent over 200 000 child deaths (approximately 1% of deaths in children <5 years of age) in India at an incremental cost of US$127 million per year. From a government perspective, state-level cost-effectiveness ranged from US$192 to US$1033 per discounted disability adjusted life years averted. With the inclusion of household health care costs, cost-effectiveness ranged from US$155-US$939 per discounted disability adjusted life year averted. These values are below the World Health Organization thresholds for cost effectiveness of public health interventions. CONCLUSIONS: Hib conjugate vaccination is a cost-effective intervention in all States of India. This conclusion does not alter with plausible changes in key parameters. Although investment in Hib conjugate vaccination would significantly increase the cost of the Universal Immunization Program, about 15% of the incremental cost would be offset by health care cost savings. Efforts should be made to expedite the nationwide introduction of Hib conjugate vaccination in India. |
Impact of Haemophilus influenzae Type b conjugate vaccine in Mongolia: prospective population-based surveillance, 2002-2010
Scott S , Altanseseg D , Sodbayer D , Nymadawa P , Bulgan D , Mendsaikhan J , Watt JP , Slack MP , Carvalho MG , Hajjeh R , Edmond KM . J Pediatr 2013 163 S8-S11 OBJECTIVES: Bacterial meningitis is associated with high mortality and long-term complications. This study assessed the impact of Haemophilus influenzae type b (Hib) conjugate vaccine on childhood bacterial meningitis in Ulaanbaatar, Mongolia. STUDY DESIGN: Prospective, active, population-based surveillance for suspected meningitis in children aged 2-59 months was conducted (February 2002-January 2011) in 6 hospitals. Clinical data, blood, and cerebrospinal fluid were collected. The impact of Hib conjugate vaccine was assessed by comparing Hib and all cause meningitis data in the 3 years preceding pentavalent conjugate vaccine implementation (2002-2004) with 3 years postimplementation (2008-2010). RESULTS: Five hundred eleven cases of suspected meningitis were identified from 2002-2011. Pentavalent conjugate vaccine coverage in December 2005 in Ulaanbaatar city was 97%. The proportion of suspected cases confirmed as Hib meningitis decreased from 25% (50/201) in the prevaccination era to 2% (4/193) in the postvaccination era (P < .0001). The annual incidence of Hib decreased from 28 cases per 100 000 children in 2002-2005 to 2 per 100 000 in 2008-2010 (P < .0001). CONCLUSIONS: This article demonstrates the marked impact of Hib conjugate vaccine introduction on meningitis in Mongolia. It is important to sustain this surveillance system to monitor the long-term impact of Hib conjugate vaccine, as well as other interventions such as pneumococcal and meningococcal vaccines. |
Bacterial meningitis surveillance in the Eastern Mediterranean Region, 2005-2010: successes and challenges of a regional network
Teleb N , Pilishvili T , Van Beneden C , Ghoneim A , Amjad K , Mostafa A , Estighamati AR , Smeo MN , Barkia A , Elkhatib M , Mujaly A , Ashmony H , Jassim KA , Hajjeh RA . J Pediatr 2013 163 S25-31 OBJECTIVE: To describe epidemiology of bacterial meningitis in the World Health Organization Eastern Mediterranean Region countries and assist in introduction of new bacterial vaccines. STUDY DESIGN: A laboratory-based sentinel surveillance was established in 2004, and up to 10 countries joined the network until 2010. Personnel at participating hospitals and national public health laboratories received training in surveillance and laboratory methods and used standard clinical and laboratory-confirmed case definitions. RESULTS: Over 22 000 suspected cases of meningitis were reported among children ≤5 years old and >6600 among children >5 years old. In children ≤5 years old, 921 of 13 125 probable cases (7.0%) were culture-confirmed. The most commonly isolated pathogens were S pneumoniae (27% of confirmed cases), N meningitidis (22%), and H influenzae (10%). Among culture-confirmed case-patients with known outcome, case-fatality rate was 7.0% and 12.2% among children ≤5 years old and those >5 years old, respectively. Declining numbers of Haemophilus influenzae type b meningitis cases within 2 years post-Haemophilus influenzae type b conjugate vaccine introduction were observed in Pakistan. CONCLUSIONS: Bacterial meningitis continues to cause significant morbidity and mortality in the Eastern Mediterranean Region. Surveillance networks for bacterial meningitis ensure that all sites are using standardized methodologies. Surveillance data are useful to monitor impact of various interventions including vaccines, but maintaining data quality requires consistent reporting and regular technical support. |
TRIVAC decision-support model for evaluating the cost-effectiveness of Haemophilus influenzae type b, pneumococcal and rotavirus vaccination
Clark A , Jauregui B , Griffiths U , Janusz CB , Bolanos-Sierra B , Hajjeh R , Andrus JK , Sanderson C . Vaccine 2013 31 Suppl 3 C19-29 The TRIVAC decision support model has been used widely in Latin America and other regions to help national teams evaluate the cost-effectiveness of Haemophilus influenzae type b (Hib) vaccine, pneumococcal conjugate vaccine (PCV) and rotavirus vaccine (RV). We describe the structure and functioning of this model, and identify the parameters with the greatest influence on the results. The TRIVAC model is a spreadsheet software program that calculates incremental cost-effectiveness ratios (ICERs) and other indicators for three childhood vaccines (Hib, PCV and RV) utilising parameters such as demography, disease burden, vaccine costs, vaccine coverage, vaccine efficacy, health service utilisation and costs. There is a good deal of uncertainty about the local values of many of the parameters that have most influence on the cost-effectiveness of these new vaccines. Cost-effectiveness models can be used to explore the implications of different values of these parameters. However, for such models to be seen as relevant and helpful by decision-makers, they need to be transparent, flexible, easy to use, and embedded in a process which is owned and led by national teams. In this paper the key drivers of cost-effectiveness in the model are identified by one-way sensitivity analyses, run for each vaccine in 147 countries. The data used are mainly from standard international sources and the published literature. The primary indicator was the discounted cost per Disability Adjusted Life-Year (DALY) averted, from a government perspective, over a 20-year period (2013-2032). For all three vaccines, the ICER was most sensitive to changes in relative coverage (the coverage of the children who would have become diseased or, more importantly, died if the population had not been vaccinated, as a % of overall national coverage) and the herd effect multiplier. Other influential parameters for all three vaccines were: the incidence and case fatality of disease, the baseline trend in disease mortality in the absence of vaccination, vaccine efficacy, vaccine price and the % decline in vaccine price per year. Important vaccine-specific parameters included the cost of Hib meningitis sequelae, PCV serotype coverage and the rotavirus gastro-enteritis (RVGE) admission rate. While vaccine efficacy, herd effects, disease mortality and vaccine price are commonly cited as important drivers of cost-effectiveness, this analysis highlights the potentially important influence of relative coverage, a parameter rarely considered in models of vaccine impact and cost-effectiveness. |
Mortality and neurodevelopmental outcomes of acute bacterial meningitis in children aged <5 years in Pakistan
Khowaja AR , Mohiuddin S , Cohen AL , Khalid A , Mehmood U , Naqvi F , Asad N , Pardhan K , Mulholland K , Hajjeh R , Zaidi AK , Shafqat S . J Pediatr 2013 163 S86-S91 e1 OBJECTIVE: Significant neurodevelopmental sequelae are known to occur after acute bacterial meningitis (ABM). This study determined the burden of such sequelae in Pakistani children aged <5 years to guide policies for Haemophilus influenzae type b (Hib) and pneumococcal vaccination. STUDY DESIGN: Cases of ABM were recruited from hospital-based surveillance and assigned to 1 of 3 etiologic groups (Hib, Streptococcus pneumoniae, or unknown etiology). Two age-matched controls were recruited for each case. Six months after enrollment, each case underwent neurologic history and examination, neurodevelopmental evaluation, and neurophysiological hearing test. Controls were assessed in parallel. RESULTS: Of 188 cases, 64 (34%) died. Mortality among subgroups were 7 (27%), 14 (28%), and 43 (39%) for Hib, Streptococcus pneumoniae, and unknown etiology, respectively. Eighty cases and 160 controls completed the assessments. Sequelae among cases included developmental delay (37%), motor deficit (31%), hearing impairment (18.5%), epilepsy (14%), and vision impairment (14%). Sequelae were higher after pneumococcal meningitis (19, 73%) compared with Hib meningitis (8, 53%). Compared with controls, cases were at significantly higher risk for all sequelae (P < .0001). CONCLUSIONS: ABM causes a substantial long-term burden of poor neurodevelopmental outcomes. Hib and pneumococcal vaccines are very effective interventions to prevent meningitis and its disabling sequelae. |
Progress towards demonstrating the impact of Haemophilus influenzae Type b conjugate vaccines globally
Hajjeh R , Mulholland K , Schuchat A , Santosham M . J Pediatr 2013 163 S1-3 Prior to the introduction of vaccines, Haemophilus influenzae type b (Hib) was the most common cause of bacterial meningitis and an important cause of severe pneumonia in children <5 years of age. Hib conjugate vaccines were introduced in developed countries during the early 1990s, resulting in a virtual elimination of Hib disease.1 However, the introduction of Hib vaccine in developing countries was delayed significantly due to multiple barriers, with major obstacles being the lack of local data on disease burden and the lack of awareness of the potential impact of the vaccine. In 2002, a group of scientific experts and public health officials gathered in Arizona, US, to discuss the epidemiology and control of Hib disease and recommended a multifaceted approach to overcome barriers for Hib vaccine introduction.2 In 2005, the GAVI Alliance funded the Hib Initiative, a consortium of public and private institutions (Johns Hopkins School of Public Health, the World Health Organization [WHO], the London School for Hygiene and Tropical Medicine, and the US Centers for Diseases Control and Prevention) to assist countries eligible for GAVI funding in making evidence-based decisions regarding the introduction of Hib vaccines into national immunizations programs. The Hib Initiative adopted a strategy based on improved communications, coordination with key partners at country, regional, and global levels, and supporting selected research studies to address gaps in Hib knowledge, particularly studies that could provide evidence and capacity to sustain vaccine programs beyond the period of GAVI support. Fortunately, significant progress in introduction of Hib vaccines has occurred over the last few years with all GAVI countries, having either introduced the vaccine already or are expected to introduce in 2013.3 | There frequently is tension in implementation programs regarding the appropriate role for research. The Hib Initiative focused on critical issues and geographic locations where scientific gaps remained and where strengthened capacity and systems could bridge to long term impacts. A decade after the Arizona meeting, the proceedings of which were reported in The Journal of Pediatrics, many scientific gaps have been filled, but a few questions still need to be answered.2 This Supplement features a number of projects that were supported by the Hib Initiative and that provide valuable lessons for meningitis and pneumonia control and accelerate uptake of new and underutilized vaccines. |
Effectiveness of Haemophilus influenzae type b conjugate vaccine on radiologically-confirmed pneumonia in young children in Pakistan
Khowaja AR , Mohiuddin S , Cohen AL , Mirza W , Nadeem N , Zuberi T , Salam B , Mubarak F , Rizvi B , Husen Y , Pardhan K , Khan KM , Raza SJ , Zuberi HK , Mustafa S , Sheikh SH , Nizamani A , Lohana H , Mulholland K , Zell E , Hajjeh R , Bosan A , Zaidi AK . J Pediatr 2013 163 S79-S85 e1 OBJECTIVE: The effectiveness of Haemophilus influenzae type b (Hib) vaccine in preventing severe pneumonia in Asian children has been questioned, and many large Asian countries yet to introduce Hib conjugate vaccine in immunization programs. The primary objective of this study was to assess Hib conjugate vaccine effectiveness (VE) on radiologically-confirmed pneumonia in children born after introduction of Hib conjugate vaccine in Pakistan. STUDY DESIGN: A matched case-control study enrolled cases of radiologically-confirmed pneumonia in several hospitals serving low-income populations during 2009-2011. Cases were matched by age and season with 3 hospital and 5 neighborhood controls. Pneumonia was diagnosed using standardized World Health Organization criteria for chest radiograph interpretation. Matched OR were estimated for VE. RESULTS: A total of 1027 children with radiologically-confirmed pneumonia were enrolled; 975 cases, 2925 hospital controls, and 4875 neighborhood controls were analyzed. The coverage for 3 doses of diphtheria-tetanus-pertussis-hepatitis B-Hib conjugate vaccine was 13.7%, 18%, and 22.7% in cases, hospital controls and neighborhood controls, respectively. Estimated Hib VE for radiologically-confirmed pneumonia was 62% with 3 doses of vaccine using hospital controls and 70% using neighborhood controls. CONCLUSIONS: Hib conjugate vaccine prevented a significant fraction of radiologically-confirmed pneumonia in children in Pakistan. Maximizing impact on child survival needs improved immunization coverage. |
Evaluation of the effectiveness of Haemophilus influenzae type b conjugate vaccine introduction against radiologically-confirmed hospitalized pneumonia in young children in Ukraine
Pilishvili T , Chernyshova L , Bondarenko A , Lapiy F , Sychova I , Cohen A , Flannery B , Hajjeh R . J Pediatr 2013 163 S12-8 OBJECTIVE: Haemophilus influenzae type b (Hib) conjugate vaccine was included into the national vaccination schedule of Ukraine in 2006. The objective of this study was to demonstrate the effectiveness of Hib conjugate vaccine against radiologically-confirmed hospitalized pneumonia in children. STUDY DESIGN: Children <2 years old with radiologically confirmed pneumonia admitted to 11 participating hospitals in Kiev and Dnepropetrovsk between April 2007 and June 2009 were included in a case-control evaluation. Four controls were matched to each case by date of birth (within 14 days) and outpatient clinic. We estimated ORs for vaccination and vaccine effectiveness ((1 - OR)*100%) using conditional logistic regression, adjusting for comorbid conditions and contraindications for vaccination. RESULTS: We enrolled 188 case-children and 735 controls. Median age was 16 months (range 4-24 months). Fifty-one percent of cases and 67% of controls received ≥1 doses of Hib conjugate vaccine; 26% of cases and 37% of controls received ≥3 doses. The effectiveness of ≥1 dose Hib conjugate vaccine was estimated at 45% (95% CI 18%-63%). CONCLUSIONS: Our study showed that Hib infections are important causes of hospitalized radiologically confirmed pneumonia in young children in Ukraine. |
Call to action on World Pneumonia Day
Hajjeh R , Whitney CG . Emerg Infect Dis 2012 18 (11) 1898-9 This month, on November 12, the world will recognize the fourth annual World Pneumonia Day. First launched in 2009 by a coalition of global health leaders (1), World Pneumonia Day aims to raise awareness about pneumonia's toll on the world's children and to promote interventions to protect against, treat, and prevent the disease. Pneumonia continues to be the leading killer of young children around the world, causing approximately 14% of all deaths in children 1 month to 5 years of age (2). It is a critical disease for countries to conquer in order to reach Millennium Development Goal 4: reducing the child mortality rate by two thirds from 1990 to 2015 (3). Most children who die from pneumonia live in developing countries, where such factors as malnutrition, crowding, and lack of access to quality health care increase the risk for death. Pneumonia kills few children in industrialized countries, although it remains among the top 10 causes of deaths in the United States, for example, because of deaths in older adults (4). |
Accelerating introduction of new vaccines: barriers to introduction and lessons learned from the recent Haemophilus influenzae type b vaccine experience
Hajjeh R . Philos Trans R Soc Lond B Biol Sci 2011 366 (1579) 2827-32 Adoption of new vaccines in developing countries is critical to reducing child mortality and meeting Millennium Development Goal 4. However, such introduction has historically suffered from significant delays that can be attributed to various factors including (i) lack of recognition of the value of a vaccine, (ii) factors related to weak health systems, and (iii) policy considerations. Recently, the Global Alliance for Vaccines and Immunization (GAVI) supported efforts to accelerate the introduction of Haemophilus influenzae type b (Hib) vaccines in developing countries, which resulted in a significant surge in vaccine adoption by these countries. The experience with Hib vaccines, as well as similar efforts by GAVI to support the introduction of new pneumococcal and rotavirus vaccines, provides a strategy for new vaccine adoption that is reviewed in this paper, providing a useful model to help accelerate the uptake of other life-saving vaccines. This strategy addresses barriers for vaccine adoption by focusing on three major areas: (i) communications to increase awareness about the various factors needed for evidence-based decisions that meet a country's health goals; (ii) research activities to answer key questions that support vaccine introduction and long-term programme sustainability; and (iii) coordination with the various stakeholders at global, regional and country levels to ensure successful programme implementation. |
International Conference on Emerging Infectious Diseases, 2010
Marano N , Smith TL , Hajjeh RA , McDonald M , Bridges CB , Martin SA , Chorba T . Emerg Infect Dis 2010 16 (11) e1 The seventh International Conference on Emerging Infectious Diseases (ICEID) was held in Atlanta, Georgia, USA, July 11-14, 2010. The conference goal was to bring together public health professionals to encourage exchange of scientific and public health information on global emerging infectious disease issues. The conference was organized by the Centers for Disease Control and Prevention (CDC), American Society for Microbiology, the Council of State and Territorial Epidemiologists, the Association of Public Health Laboratories, and the World Health Organization; additional support was provided by 40 other multidisciplinary public health partners. |
Methodology and measurement of the effectiveness of Haemophilus influenzae type b vaccine: systematic review
O'Loughlin RE , Edmond K , Mangtani P , Cohen AL , Shetty S , Hajjeh R , Mulholland K . Vaccine 2010 28 (38) 6128-36 The use of the highly effective Haemophilus influenzae type b (Hib) conjugate vaccine has increased globally. We review the benefits and limitations of studies measuring Hib vaccine effectiveness (VE). We critically examine the case-control approach by assessing the similarities and differences in methodology and findings and discuss the need for future Hib VE studies. In the absence of good surveillance data, vaccine effectiveness studies can play an important role, particularly with the increasing use of pneumococcal vaccine that has not been well tested under field conditions in less developed countries. However, the effectiveness of Hib vaccine has been well documented so the need for future VE Hib studies is minimal. |
Global use of Haemophilus influenzae type b conjugate vaccine
Ojo LR , O'Loughlin RE , Cohen AL , Loo JD , Edmond KM , Shetty SS , Bear AP , Privor-Dumm L , Griffiths UK , Hajjeh R . Vaccine 2010 28 (43) 7117-22 Haemophilus influenzae type b (Hib) conjugate vaccines have been underutilized globally. We report progress in global use of Hib vaccines included in national immunization schedules. The number of countries using Hib vaccine increased from 89/193 (46%) in 2004 to 158/193 (82%) by the end of 2009. The increase was greatest among low-income countries eligible for financial support from the GAVI Alliance [13/75 (17%) in 2004, 60/72 (83%) by the end of 2009], and can be attributed to various factors. Additional efforts are still needed to increase vaccine adoption in lower middle income countries [20/31 (65%) by the end of 2009]. |
Supporting new vaccine introduction decisions: Lessons learned from the Hib Initiative experience
Hajjeh RA , Privor-Dumm L , Edmond K , O'Loughlin R , Shetty S , Griffiths UK , Bear AP , Cohen AL , Chandran A , Schuchat A , Mulholland EK , Santosham M . Vaccine 2010 28 (43) 7123-9 The introduction of Haemophilus influenzae type b (Hib) vaccine in developing countries has suffered from a long delay. Between 2005 and 2009, a surge in Hib vaccine adoption took place, particularly among GAVI-eligible countries. Several factors contributed to the increase in Hib vaccine adoption, including support provided by the Hib Initiative, a project funded by the GAVI Alliance in 2005 to accelerate evidence-informed decisions for use of Hib vaccine. This paper reviews the strategy adopted by the Hib Initiative and the lessons learned in the process, which provide a useful model to accelerate uptake of other new vaccines. |
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