Last data update: May 13, 2024. (Total: 46773 publications since 2009)
Records 1-9 (of 9 Records) |
Query Trace: Nandy R[original query] |
---|
Implementing the immunization agenda 2030: A framework for action through coordinated planning, monitoring & evaluation, ownership & accountability, and communications & advocacy
Lindstrand A , Mast E , Churchill S , Rahimi N , Grevendork J , Brooks A , Magnus E , Nandy R , O'Brien KL . Vaccine 2023 In November 2020, the Seventy-Third World Health Assembly endorsed the Immunization Agenda 2030: A Global Strategy to Leave No One Behind (IA2030) in decision WHA73/(9). IA2030 defines what needs to happen to achieve the global vision of a world where everyone, everywhere, at every age fully benefits from vaccines for good health and well-being. | | IA2030 is a global strategy created for the global community and requiring broad ownership by all immunization and non-immunization stakeholders, including those involved in health system strengthening and disease-specific initiatives. While WHO was asked to lead the development of IA2030, all stakeholders co-created, co-developed and now co-own it. IA2030 has been designed to respond to the interests of each and every country, regardless of income level or geography. Recognizing that the most important actions for success must be taken by individual Member States, IA2030 aims to reinforce country ownership for planning and implementing effective and comprehensive vaccination programmes. |
Evolving epidemiology of poliovirus serotype 2 following withdrawal of the type 2 oral poliovirus vaccine
Macklin GR , O'Reilly KM , Grassly NC , Edmunds WJ , Mach O , Santhana Gopala Krishnan R , Voorman A , Vertefeuille JF , Abdelwahab J , Gumede N , Goel A , Sosler S , Sever J , Bandyopadhyay AS , Pallansch MA , Nandy R , Mkanda P , Diop OM , Sutter RW . Science 2020 368 (6489) 401-405 While there have been no cases of type-2 wild poliovirus for over 20 years, transmission of type-2 vaccine-derived poliovirus (VDPV2) and associated paralytic cases in several continents represent a threat to eradication. The withdrawal of the type-2 component of oral poliovirus vaccine (OPV2) was implemented in April 2016 to stop VDPV2 emergence and secure eradication of all poliovirus type 2. Globally, children born after this date have limited immunity to prevent transmission. Using a statistical model, we estimate the emergence date and source of VDPV2s detected between May 2016 and November 2019. Outbreak response campaigns with monovalent OPV2 are the only available method to induce immunity to prevent transmission. Yet, our analysis shows that using monovalent OPV2 is generating more paralytic VDPV2 outbreaks with the potential for establishing endemic transmission. The novel OPV2 is urgently required, alongside a contingency strategy if this vaccine does not materialize or perform as anticipated. |
Cessation of trivalent oral poliovirus vaccine and introduction of inactivated poliovirus vaccine - worldwide, 2016
Hampton LM , Farrell M , Ramirez-Gonzalez A , Menning L , Shendale S , Lewis I , Rubin J , Garon J , Harris J , Hyde T , Wassilak S , Patel M , Nandy R , Chang-Blanc D . MMWR Morb Mortal Wkly Rep 2016 65 (35) 934-938 Since the 1988 World Health Assembly resolution to eradicate poliomyelitis, transmission of the three types of wild poliovirus (WPV) has been sharply reduced. WPV type 2 (WPV2) has not been detected since 1999 and was declared eradicated in September 2015. Because WPV type 3 has not been detected since November 2012, WPV type 1 (WPV1) is likely the only WPV that remains in circulation. This marked progress has been achieved through widespread use of oral poliovirus vaccines (OPVs), most commonly trivalent OPV (tOPV), which contains types 1, 2, and 3 live, attenuated polioviruses and has been a mainstay of efforts to prevent polio since the early 1960s. However, attenuated polioviruses in OPV can undergo genetic changes during replication, and in communities with low vaccination coverage, can result in vaccine-derived polioviruses (VDPVs) that can cause paralytic polio indistinguishable from the disease caused by WPVs. Among the 721 polio cases caused by circulating VDPVs (cVDPVs*) detected during January 2006-May 2016, type 2 cVDPVs (cVDPV2s) accounted for >94%. Eliminating the risk for polio caused by VDPVs will require stopping all OPV use. The first stage of OPV withdrawal involved a global, synchronized replacement of tOPV with bivalent OPV (bOPV) containing only types 1 and 3 attenuated polioviruses, planned for April 18-May 1, 2016, thereby withdrawing OPV type 2 from all immunization activities. Complementing the switch from tOPV to bOPV, introduction of at least 1 dose of injectable, trivalent inactivated poliovirus vaccine (IPV) into childhood immunization schedules reduces risks from and facilitates responses to cVDPV2 outbreaks. All 155 countries and territories that were still using OPV in immunization schedules in 2015 have reported that they had ceased use of tOPV by mid-May 2016. As of August 31, 2016, 173 (89%) of 194 World Health Organization (WHO) countries included IPV in their immunization schedules. The cessation of tOPV use is a major milestone toward the global goal of eradicating polio; however, careful surveillance for polioviruses and prompt, aggressive responses to polio outbreaks are still needed to realize a polio-free world. |
Strengthening the evidence base for health programming in humanitarian crises
Ager A , Burnham G , Checchi F , Gayer M , Grais RF , Henkens M , Massaquoi MB , Nandy R , Navarro-Colorado C , Spiegel P . Science 2014 345 (6202) 1290-2 Given the growing scale and complexity of responses to humanitarian crises, it is important to develop a stronger evidence base for health interventions in such contexts. Humanitarian crises present unique challenges to rigorous and effective research, but there are substantial opportunities for scientific advance. Studies need to focus where the translation of evidence from noncrisis scenarios is not viable and on ethical ways of determining what happens in the absence of an intervention. Robust methodologies suited to crisis settings have to be developed and used to assess interventions with potential for delivery at scale. Strengthening research capacity in the low- to middle-income countries that are vulnerable to crises is also crucial. |
Rapid monitoring in vaccination campaigns during emergencies: the post-earthquake campaign in Haiti
Rainey JJ , Sugerman D , Brennan M , Cadet JR , Ernsly J , Lacapere F , Danovaro-Holliday MC , Mubalama JC , Nandy R . Bull World Health Organ 2013 91 (12) 957-62 PROBLEM: The earthquake that struck Haiti in January 2010 caused 1.5 million people to be displaced to temporary camps. The Haitian Ministry of Public Health and Population and global immunization partners developed a plan to deliver vaccines to those residing in these camps. A strategy was needed to determine whether the immunization targets set for the campaign were achieved. APPROACH: Following the vaccination campaign, staff from the Ministry of Public Health and Population interviewed convenience samples of households - in specific predetermined locations in each of the camps - regarding receipt of the emergency vaccinations. A camp was targeted for "mop-up vaccination" - i.e. repeat mass vaccination - if more than 25% of the children aged 9 months to 7 years in the sample were found not to have received the emergency vaccinations. LOCAL SETTING: Rapid monitoring was implemented in camps located in the Port-au-Prince metropolitan area. Camps that housed more than 5000 people were monitored first. RELEVANT CHANGES: By the end of March 2010, 72 (23%) of the 310 vaccinated camps had been monitored. Although 32 (44%) of the monitored camps were targeted for mop-up vaccination, only six of them had received such repeat mass vaccination when checked several weeks after monitoring. LESSONS LEARNT: Rapid monitoring was only marginally beneficial in achieving immunization targets in the temporary camps in Port-au-Prince. More research is needed to evaluate the utility of conventional rapid monitoring, as well as other strategies, during post-disaster vaccination campaigns that involve mobile populations, particularly when there is little capacity to conduct repeat mass vaccination. |
Economic evaluation of a Child Health Days strategy to deliver multiple maternal and child health interventions in Somalia
Vijayaraghavan M , Wallace A , Mirza IR , Kamadjeu R , Nandy R , Durry E , Everard M . J Infect Dis 2012 205 Suppl 1 S134-40 INTRODUCTION: Child Health Days (CHDs) are increasingly used by countries to periodically deliver multiple maternal and child health interventions as time-limited events, particularly to populations not reached by routine health services. In countries with a weak health infrastructure, this strategy could be used to reach many underserved populations with an integrated package of services. In this study, we estimate the incremental costs, impact, cost-effectiveness, and return on investment of 2 rounds of CHDs that were conducted in Somalia in 2009 and 2010. METHODS: We use program costs and population estimates reported by the World Health Organization and United Nations Children's Fund to estimate the average cost per beneficiary for each of 9 interventions delivered during 2 rounds of CHDs implemented during the periods of December 2008 to May 2009 and August 2009 to April 2010. Because unstable areas were unreachable, we calculated costs for targeted and accessible beneficiaries. We model the impact of the CHDs on child mortality using the Lives Saved Tool, convert these estimates of mortality reduction to life years saved, and derive the cost-effectiveness ratio and the return on investment. RESULTS: The estimated average incremental cost per intervention for each targeted beneficiary was $0.63, with the cost increasing to $0.77 per accessible beneficiary. The CHDs were estimated to save the lives of at least 10,000 or 500,000 life years for both rounds combined. The CHDs were cost-effective at $34.00/life year saved. For every $1 million invested in the strategy, an estimated 615 children's lives, or 29,500 life years, were saved. If the pentavalent vaccine had been delivered during the CHDs instead of diphtheria-pertussis-tetanus vaccine, an additional 5000 children's lives could have been saved. CONCLUSIONS: Despite high operational costs, CHDs are a very cost-effective service delivery strategy for addressing the leading causes of child mortality in a conflict setting like Somalia and compare favorably with other interventions rated as health sector "best buys" in sub-Saharan Africa. |
Laboratory characterization of measles virus infection in previously vaccinated and unvaccinated individuals
Hickman CJ , Hyde TB , Sowers SB , Mercader S , McGrew M , Williams NJ , Beeler JA , Audet S , Kiehl B , Nandy R , Tamin A , Bellini WJ . J Infect Dis 2011 204 Suppl 1 S549-58 Waning immunity or secondary vaccine failure (SVF) has been anticipated by some as a challenge to global measles elimination efforts. Although such cases are infrequent, measles virus (MeV) infection can occur in vaccinated individuals following intense and/or prolonged exposure to an infected individual and may present as a modified illness that is unrecognizable as measles outside of the context of a measles outbreak. The immunoglobulin M response in previously vaccinated individuals may be nominal or fleeting, and viral replication may be limited. As global elimination proceeds, additional methods for confirming modified measles cases may be needed to understand whether SVF cases contribute to continued measles virus (MeV) transmission. In this report, we describe clinical symptoms and laboratory results for unvaccinated individuals with acute measles and individuals with SVF identified during MeV outbreaks. SVF cases were characterized by the serological parameters of high-avidity antibodies and distinctively high levels of neutralizing antibody. These parameters may represent useful biomarkers for classification of SVF cases that previously could not be confirmed as such using routine laboratory diagnostic techniques. |
Should outbreak response immunization be recommended for measles outbreaks in middle- and low-income countries? An update
Cairns KL , Perry RT , Ryman TK , Nandy RK , Grais RF . J Infect Dis 2011 204 Suppl 1 S35-46 BACKGROUND: Measles caused mortality in >164,000 children in 2008, with most deaths occurring during outbreaks. Nonetheless, the impact and desirability of conducting measles outbreak response immunization (ORI) in middle- and low-income countries has been controversial. World Health Organization guidelines published in 1999 recommended against ORI in such settings, although recently these guidelines have been reversed for countries with measles mortality reduction goals. METHODS: We searched literature published during 1995-2009 for papers reporting on measles outbreaks. Papers identified were reviewed by 2 reviewers to select those that mentioned ORI. World Bank classification of country income was used to identify reports of outbreaks in middle- and low-income countries. RESULTS: We identified a total of 485 articles, of which 461 (95%) were available. Thirty-eight of these papers reported on a total of 38 outbreaks in which ORI was used. ORI had a clear impact in 16 (42%) of these outbreaks. In the remaining outbreaks, we were unable to independently assess the impact of ORI. CONCLUSIONS: These findings generally support ORI in middle- and low-income countries. However, the decision to conduct ORI and the nature and extent of the vaccination response need to be made on a case-by-case basis. |
Challenges in measuring measles case fatality ratios in settings without vital registration
Cairns KL , Nandy R , Grais RF . Emerg Themes Epidemiol 2010 7 (4) (19 July 2010) Measles, a highly infectious vaccine-preventable viral disease, is potentially fatal. Historically, measles case-fatality ratios (CFRs) have been reported to vary from 0.1% in the developed world to as high as 30% in emergency settings. Estimates of the global burden of mortality from measles, critical to prioritizing measles vaccination among other health interventions, are highly sensitive to the CFR estimates used in modeling; however, due to the lack of reliable, up-to-date data, considerable debate exists as to what CFR estimates are appropriate to use. To determine current measles CFRs in high-burden settings without vital registration we have conducted six retrospective measles mortality studies in such settings. This paper examines the methodological challenges of this work and our solutions to these challenges, including the integration of lessons from retrospective all-cause mortality studies into CFR studies, approaches to laboratory confirmation of outbreaks, and means of obtaining a representative sample of case-patients. Our experiences are relevant to those conducting retrospective CFR studies for measles or other diseases, and to those interested in all-cause mortality studies. |
- Page last reviewed:Feb 1, 2024
- Page last updated:May 13, 2024
- Content source:
- Powered by CDC PHGKB Infrastructure