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  • Potential use of microarray patches for vaccine delivery in low- and middle-income countries

    Peyraud, N; Zehrung, D; Jarrahian, C; Frivold, C; Orubu, T; Giersing, B (Elsevier, 2019-06-28)
    Microarray patches (MAPs), also referred to as microneedle patches, are a novel methodology that have the potential to overcome barriers to vaccine delivery in low- and middle-income countries (LMICs), and transform the way that vaccines are delivered within immunization programs. The World Health Organization’s Initiative for Vaccine Research and its partners are working to understand how MAPs could ease vaccine delivery and increase equitable access to vaccines in LMICs. Global stakeholders have been engaged to evaluate technical, economic, and programmatic challenges; to validate assumptions where possible; and to propose areas of focus to facilitate future vaccine-MAP product development. This report summarizes those learnings.
  • Sub-national variation in measles vaccine coverage and outbreak risk: a case study from a 2010 outbreak in Malawi.

    Kundrick, A; Huang, Z; Carran, S; Kagoli, M; Grais, RF; Hurtado, N; Ferrari, M (BioMed Central, 2019-06-15)
    Background Despite progress towards increasing global vaccination coverage, measles continues to be one of the leading, preventable causes of death among children worldwide. Whether and how to target sub-national areas for vaccination campaigns continues to remain a question. We analyzed three metrics for prioritizing target areas: vaccination coverage, susceptible birth cohort, and the effective reproductive ratio (RE) in the context of the 2010 measles epidemic in Malawi. Methods Using case-based surveillance data from the 2010 measles outbreak in Malawi, we estimated vaccination coverage from the proportion of cases reporting with a history of prior vaccination at the district and health facility catchment scale. Health facility catchments were defined as the set of locations closer to a given health facility than to any other. We combined these estimates with regional birth rates to estimate the size of the annual susceptible birth cohort. We also estimated the effective reproductive ratio, RE, at the health facility polygon scale based on the observed rate of exponential increase of the epidemic. We combined these estimates to identify spatial regions that would be of high priority for supplemental vaccination activities. Results The estimated vaccination coverage across all districts was 84%, but ranged from 61 to 99%. We found that 8 districts and 354 health facility catchments had estimated vaccination coverage below 80%. Areas that had highest birth cohort size were frequently large urban centers that had high vaccination coverage. The estimated RE ranged between 1 and 2.56. The ranking of districts and health facility catchments as priority areas varied depending on the measure used. Conclusions Each metric for prioritization may result in discrete target areas for vaccination campaigns; thus, there are tradeoffs to choosing one metric over another. However, in some cases, certain areas may be prioritized by all three metrics. These areas should be treated with particular concern. Furthermore, the spatial scale at which each metric is calculated impacts the resulting prioritization and should also be considered when prioritizing areas for vaccination campaigns. These methods may be used to allocate effort for prophylactic campaigns or to prioritize response for outbreak response vaccination.
  • Oral cholera vaccination in hard-to-reach communities, Lake Chilwa, Malawi

    Grandesso, F; Rafael, F; Chipeta, S; Alley, I; Saussier, C; Nogareda, F; Burns, M; Lechevalier, P; Page, AL; Salumu, L; Pezzoli, L; Mwesawina, M; Cavailler, P; Mengel, M; Luquero, FJ; Cohuet, S (The World Health Organization, 2018-12-01)
    To evaluate vaccination coverage, identify reasons for non-vaccination and assess satisfaction with two innovative strategies for distributing second doses in an oral cholera vaccine campaign in 2016 in Lake Chilwa, Malawi, in response to a cholera outbreak.
  • Oral cholera vaccination in hard-to-reach communities, Lake Chilwa, Malawi

    Grandesso, F; Rafael, F; Chipeta, S; Alley, I; Saussier, C; Nogareda, F; Burns, M; Lechevalier, P; Page, AL; Salumu, L; Pezzoli, L; Mwesawina, M; Cavailler, P; Mengel, M; Luquero, FJ; Cohuet, S (World Health Organization, 2018-09-27)
  • Reactive and pre-emptive vaccination strategies to control hepatitis E infection in emergency and refugee settings: A modelling study

    Cooper, BS; White, LJ; Siddiqui, R (Public Library of Science, 2018-09-25)
    Hepatitis E Virus (HEV) is the leading cause of acute viral hepatitis globally. Symptomatic infection is associated with case fatality rates of ~20% in pregnant women and it is estimated to account for ~10,000 annual pregnancy-related deaths in southern Asia alone. Recently, large and well-documented outbreaks with high mortality have occurred in displaced population camps in Sudan, Uganda and South Sudan. However, the epidemiology of HEV is poorly defined, and the value of different immunisation strategies in outbreak settings uncertain. We aimed to estimate the critical epidemiological parameters for HEV and to evaluate the potential impact of both reactive vaccination (initiated in response to an epidemic) and pre-emptive vaccination.
  • Safety of the rVSV ZEBOV vaccine against Ebola Zaire among frontline workers in Guinea

    Juan-Giner, A; Tchaton, M; Jemmy, JP; Soumah, A; Boum, Y; Faga, EM; Cisse, M; Grais, RF (Elsevier, 2018-09-25)
    As part of the ring vaccination trial in Guinea, Front Line Workers were invited to participate in a sub-study to provide additional information on the immunogenicity and safety of rVSVΔG/ZEBOV-GP. Here we summarize the information on the safety follow-up.
  • Progress and Challenges in Using Oral Cholera Vaccines to Control Outbreaks: The Médecins Sans Frontières Experience

    Ciglenecki, I; Azman, AS; Jamet, C; Serafini, M; Luquero, FJ; Cabrol, JC (Oxford University Press, 2018-09-14)
    The use of oral cholera vaccine (OCV) has increased since 2011, when Shanchol, the first OCV suitable for large-scale use, became available. Médecins Sans Frontières considers OCVs an essential cholera outbreak control tool and has contributed to generating new evidence on OCV use in outbreaks. We showed that large-scale mass campaigns are feasible during outbreaks, documented high short-term effectiveness and showed that vaccines are likely safe in pregnancy. We found that a single-dose regimen has high short-term effectiveness, making rapid delivery of vaccine during outbreaks easier, especially given the on-going global vaccine shortage. Despite progress, OCV has still not been used widely in some of the largest recent outbreaks and thousands of cholera deaths are reported every year. While working towards improving our tools to protect those most at-risk of cholera, we must strive to use all available effective interventions in efficient ways, including OCV, to prevent avoidable deaths today.
  • Oral cholera vaccine in cholera prevention and control, Malawi

    M'bangombe, M; Pezzoli, L; Reeder, B; Kabuluzi, S; Msyamboza, K; Masuku, H; Ngwira, B; Cavailler, P; Grandesso, F; Palomares, A; Beck, N; Shaffer, A; MacDonald, E; Senbete, M; Lessler, J; Moore, SM; Azman, AS (World Health Organization, 2018-06-01)
    With limited global supplies of oral cholera vaccine, countries need to identify priority areas for vaccination while longer-term solutions, such as water and sanitation infrastructure, are being developed.
  • Safety of a heat-stable rotavirus vaccine among children in Niger: Data from a phase 3, randomized, double-blind, placebo-controlled trial

    Coldiron, ME; Guindo, O; Makarimi, R; Soumana, I; Matar Seck, A; Garba, S; Macher, E; Isanaka, S; Grais, RF (Elsevier, 2018-05-08)
    Rotavirus remains a major cause of diarrhea among children under 5 years of age. The efficacy of RotaSIIL, a pentavalent rotavirus vaccine, was shown in an event-driven trial in Niger. We describe the two-year safety follow-up of this trial.
  • Highly targeted cholera vaccination campaigns in urban setting are feasible: The experience in Kalemie, Democratic Republic of Congo

    Massing, LA; Aboubakar, S; Blake, A; Page, AL; Cohuet, S; Ngandwe, A; Mukomena Sompwe, E; Ramazani, R; Allheimen, M; Levaillant, P; Lechevalier, P; Kashimi, M; de la Motte, A; Calmejane, A; Bouhenia, M; Dabire, E; Bompangue, D; Kebela, B; Porten, K; Luquero, F (Public Library of Science, 2018-05-07)
    Oral cholera vaccines are primarily recommended by the World Health Organization for cholera control in endemic countries. However, the number of cholera vaccines currently produced is very limited and examples of OCV use in endemic countries, and especially in urban settings, are scarce. A vaccination campaign was organized by Médecins Sans Frontières and the Ministry of Health in a highly endemic area in the Democratic Republic of Congo. This study aims to describe the vaccine coverage achieved with this highly targeted vaccination campaign and the acceptability among the vaccinated communities.
  • The new WHO decision-making framework on vaccine use in acute humanitarian emergencies: MSF experience in Minkaman, South Sudan

    Rull, M; Masson, S; Peyraud, N; Simonelli, M; Ventura, A; Dorion, C; Luquero, FJ; Uzzeni, F; Cigleneki, I (BioMed Central, 2018-03-26)
    The main causes of death during population movements can be prevented by addressing the population's basic needs. In 2013, the World Health Organization (WHO) issued a framework for decision making to help prioritize vaccinations in acute humanitarian emergencies. This article describes MSF's experience of applying this framework in addition to addressing key population needs in a displacement setting in Minkaman, South Sudan.
  • Single-Dose Cholera Vaccine in Response to an Outbreak in Zambia

    Ferreras, E; Chizema-Kawesha, E; Blake, A; Chewe, O; Mwaba, J; Zulu, G; Poncin, M; Rakesh, A; Page, AL; Stoitsova, S; Voute, C; Uzzeni, F; Robert, H; Serafini, M; Matapo, B; Eiros, JM; Quilici, ML; Pezzoli, L; Azman, AS; Cohuet, S; Ciglenecki, I; Malama, K; Luquero, FJ (Massachusetts Medical Society, 2018-02-08)
  • Infectious Disease Risk and Vaccination in Northern Syria after 5 Years of Civil War: The MSF Experience

    de Lima Pereira, A; Southgate, R; Ahmed, H; O'Connor, P; Cramond, V; Lenglet, A (Public Library of Science, 2018-02-02)
    In 2015, following an influx of population into Kobanê in northern Syria, Médecins Sans Frontières (MSF) in collaboration with the Kobanê Health Administration (KHA) initiated primary healthcare activities. A vaccination coverage survey and vaccine-preventable disease (VPD) risk analysis were undertaken to clarify the VPD risk and vaccination needs. This was followed by a measles Supplementary Immunization Activity (SIA). We describe the methods and results used for this prioritisation activity around vaccination in Kobanê in 2015.
  • Immunogenicity and Protection from a Single Dose of Internationally available killed oral Cholera Vaccine: a systematic review and meta-analysis

    Lopez, AL; Deen, J; Azman, AS; Luquero, FJ; Kanungo, S; Dutta, S; von Seidlein, L; Sack, DA (Oxford University Press, 2017-11-21)
    In addition to improved water supply and sanitation, the two-dose killed oral cholera vaccine (OCV) is an important tool for the prevention and control of cholera. We aimed to document the immunogenicity and protection (efficacy and effectiveness) conferred by a single OCV dose against cholera. The meta-analysis showed an estimated 73% and 77% of individuals seroconverted to the Ogawa and Inaba serotypes, respectively, after an OCV first dose. The estimates of single-dose vaccine protection from available studies are 87% at 2 months decreasing to 33% at 2 years. Current immunologic and clinical data suggest that protection conferred by a single dose of killed OCV may be sufficient to reduce short-term risk in outbreaks or other high-risk settings, which may be especially useful when vaccine supply is limited. However, until more data suggests otherwise, a second dose should be given as soon as circumstances allow to ensure robust protection.
  • Improving rotavirus vaccine coverage: Can newer-generation and locally produced vaccines help?

    Deen, J; Lopez, AL; Kanungo, S; Wang, XY; Anh, DD; Tapia, M; Grais, RF (Taylor & Francis, 2017-11-14)
    There are two internationally available WHO-prequalified oral rotavirus vaccines (Rotarix and RotaTeq), two rotavirus vaccines licensed in India (Rotavac and Rotasiil), one in China (Lanzhou lamb rotavirus vaccine) and one in Vietnam (Rotavin-M1), and several candidates in development. Rotavirus vaccination has been rolled out in Latin American countries and is beginning to be deployed in sub-Saharan African countries but middle- and low-income Asian countries have lagged behind in rotavirus vaccine introduction. We provide a mini-review of the leading newer-generation rotavirus vaccines and compare them with Rotarix and RotaTeq. We discuss how the development and future availability of newer-generation rotavirus vaccines that address the programmatic needs of poorer countries may help scale-up rotavirus vaccination where it is needed.
  • Carriage Prevalence and Serotype Distribution of Streptococcus Pneumoniae Prior to 10-Valent Pneumococcal Vaccine Introduction: A Population-Based Cross-Sectional Study in South Western Uganda, 2014

    Nackers, F; Cohuet, S; le Polain de Waroux, O; Langendorf, C; Nyehangane, D; Ndazima, D; Nanjebe, D; Karani, A; Tumwesigye, E; Mwanga-Amumpaire, J; Scott, J; Grais, R (Elsevier, 2017-08-04)
    Information on Streptococcus pneumoniae nasopharyngeal (NP) carriage before the pneumococcal conjugate vaccine (PCV) introduction is essential to monitor impact. The 10-valent PCV (PCV10) was officially introduced throughout Ugandan national childhood immunization programs in 2013 and rolled-out countrywide during 2014. We aimed to measure the age-specific Streptococcus pneumoniae carriage and serotype distribution across all population age groups in the pre-PCV10 era in South Western Uganda.
  • Did the Ebola Outbreak Disrupt Immunisation Services? A Case Study from Liberia

    Wesseh, C; Najjemba, R; Edwards, J; Owiti, P; Tweya, H; Bhat, P (International Union Against Tuberculosis and Lung Disease, 2017-06-21)
    Setting: All health facilities providing routine immunisation services in Liberia. Objective: To compare the number of routine facility-based and outreach immunisations and measles cases before, during and after the Ebola outbreak. Design: A descriptive cross-sectional study. Results: Immunisation coverage for fully immunised children before the Ebola outbreak was 73%. Immunisation coverage for all antigens declined by half compared to baseline during the outbreak. These findings were similar in facility-based and outreach immunisations. During the outbreak, the proportion of fully immunised children dropped by respectively 58%, 33% and 39% in the most, moderately and least Ebola-affected counties. Immunisation rate of recovery in the post-Ebola period was respectively 82%, 21% and 9% in the most, moderately and least affected counties compared to the Ebola-outbreak period. Outreach immunisation recovered slowly compared to facility-based immunisation. The mean number of measles cases reported per month was 12 pre-Ebola, 16 Ebola and 60 post-Ebola. Conclusion: This study provides insights into the possible impact of an Ebola outbreak on countrywide immunisation. The outbreak weakened a struggling national immunisation programme, and post-outbreak recovery took significant time, which likely contributed to the measles epidemic. Recommendations for the improvement of immunisation services that could limit further preventable epidemics in Liberia and similar contexts at risk for Ebola are provided.
  • Neighborhood-Targeted and Case-Triggered Use of a Single Dose of Oral Cholera Vaccine in an Urban Setting: Feasibility and Vaccine Coverage

    Parker, L; Rumunu, J; Jamet, C; Kenyi, Y; Lino, R; Wamala, J; Mpairwe, A; Muller, V; Llosa, A; Uzzeni, F; Luquero, F; Ciglenecki, I; Azman, A (Public Library of Science, 2017-06-08)
    In June 2015, a cholera outbreak was declared in Juba, South Sudan. In addition to standard outbreak control measures, oral cholera vaccine (OCV) was proposed. As sufficient doses to cover the at-risk population were unavailable, a campaign using half the standard dosing regimen (one-dose) targeted high-risk neighborhoods and groups including neighbors of suspected cases. Here we report the operational details of this first public health use of a single-dose regimen of OCV and illustrate the feasibility of conducting highly targeted vaccination campaigns in an urban area.
  • Vaccination Against Cholera in Juba - Authors' Reply

    Ciglenecki, I; Azman, AS; Rumunu, J; Cabrol, JC; Luquero, FJ (Elsevier, 2017-05-01)
  • Economic Impact of Thermostable Vaccines

    Lee, BY; Wedlock, PT; Haidari, LA; Elder, K; Potet, J; Manring, R; Connor, DL; Spiker, ML; Bonner, K; Rangarajan, A; Hunyh, D; Brown, ST (Elsevier, 2017-04-25)
    While our previous work has shown that replacing existing vaccines with thermostable vaccines can relieve bottlenecks in vaccine supply chains and thus increase vaccine availability, the question remains whether this benefit would outweigh the additional cost of thermostable formulations.

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