RESUMO
BACKGROUND: Influenza vaccination is uncommon in low-resource settings. We evaluated aspects of operational feasibility of influenza vaccination programs targeting risk groups in the World Health Organization (WHO) African (AFR) and South-East Asian (SEAR) Regions. METHODS: We estimated routine immunization and influenza vaccination campaign doses, doses per vaccinator, and cold storage requirements for 1 simulated country in each region using evidence-based population distribution, vaccination schedule, and vaccine volumes. Influenza vaccination targeted persons <5 years, pregnant women, persons with chronic diseases, persons ≥65 years, and healthcare workers (HCW). For the AFR country, we compared vaccine volumes to actual storage capacities. RESULTS: Targeting HCW had a small operational impact, and subsequent findings exclude this group. During 3-month influenza vaccination campaigns, monthly doses delivered in the AFR country increased from 15.0% for ≥65 years to 93.1% for <5 years and in the SEAR country from 19.6% for pregnant women to 145.0% for persons with chronic diseases. National-level cold storage capacity requirements increased in the AFR country from 4.1% for ≥65 years to 20.3% for <5 years and in the SEAR country from 3.9% for pregnant women to 28.8% for persons with chronic diseases. Subnational-level cold storage capacity requirements increased in the AFR country from 5.9% for ≥65 years to 36.8% for <5 years and the SEAR country from 17.6% for pregnant women to 56.0% for persons with chronic diseases. CONCLUSIONS: Influenza vaccination of most risk groups will require substantial increases in doses, doses per vaccinator, and cold storage capacity in countries where infrastructure and resources are limited.
Assuntos
Vacinas contra Influenza , Influenza Humana , Estudos de Viabilidade , Feminino , Humanos , Programas de Imunização , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Gravidez , Estações do Ano , Vacinação , Organização Mundial da SaúdeRESUMO
BACKGROUND: SARS-CoV-2 vaccines will be deployed to countries with limited immunization systems. METHODS: We assessed the effect of deploying SARS-Cov-2 vaccines on cold storage capacity and immunization workload in a simulated WHO African Region country using region-specific data on immunization, population, healthcare workers (HCWs), cold storage capacity (quartile values for national and subnational levels), and characteristics of an approved SARS-CoV-2 vaccine. We calculated monthly increases in vaccine doses, doses per vaccinator, and cold storage volumes for four-month SARS-CoV-2 vaccination campaigns targeting risk groups compared to routine immunization baselines. RESULTS: Administering SARS-CoV-2 vaccines to risk groups would increase total monthly doses by 27.0% for ≥ 65 years, 91.7% for chronic diseases patients, and 1.1% for HCWs. Assuming median nurse density estimates adjusted for absenteeism and proportion providing immunization services, SARS-CoV-2 vaccination campaigns would increase total monthly doses per vaccinator by 29.3% for ≥ 65 years, 99.6% for chronic diseases patients, and 1.2% for HCWs. When we applied quartiles of actual African Region country vaccine storage capacity, routine immunization vaccine volumes exceeded national-level storage capacity for at least 75% of countries, but subnational levels had sufficient storage capacity for SARS-CoV-2 vaccines for at least 75% of countries. CONCLUSIONS: In the WHO African Region, SARS-CoV-2 vaccination campaigns would substantially increase doses per vaccinator and cold storage capacity requirements over routine immunization baselines. Pandemic vaccination campaigns would increase storage requirements of national-level stores already at their limits, but sufficient capacity exists at subnational levels. Immediate attention to strengthening immunization systems is essential to support pandemic responses.
Assuntos
Vacinas contra COVID-19/administração & dosagem , COVID-19/prevenção & controle , Programas de Imunização/organização & administração , Refrigeração , Carga de Trabalho , Adolescente , Adulto , África , Idoso , Criança , Pré-Escolar , Humanos , Pessoa de Meia-Idade , Vacinação , Organização Mundial da Saúde , Adulto JovemRESUMO
BACKGROUND: When available, SARS-CoV-2 vaccines will be deployed to countries with limited immunization systems. METHODS: We conducted an immunization capacity assessment of a simulated WHO African Region country using region-specific data on immunization, population, healthcare workers (HCWs), vaccine cold storage capacity (quartile values for national and subnational levels), and characteristics of influenza vaccines to represent future SARS-CoV-2 vaccines. We calculated monthly increases in vaccine doses, doses per vaccinator, and cold storage volumes for four-month SARS-CoV-2 vaccination campaigns targeting risk groups compared to routine immunization baselines. FINDINGS: Administering SARS-CoV-2 vaccines to risk groups would increase total monthly doses by 27.0% for ≥65 years, 91.7% for chronic diseases patients, and 1.1% for HCWs. Assuming median nurse density estimates adjusted for absenteeism and proportion providing immunization services, SARS-CoV-2 vaccination campaigns would increase total monthly doses per vaccinator by 29.3% for ≥65 years, 99.6% for chronic diseases patients, and 1.2% for HCWs. When we applied quartiles of actual African Region country vaccine storage capacity, routine immunization vaccine volumes exceeded national-level storage capacity for at least 75% of countries, but subnational levels had sufficient storage capacity for SARS-CoV-2 vaccines for at least 75% of countries. INTERPRETATION: In the WHO African Region, SARS-CoV-2 vaccination campaigns would substantially increase doses per vaccinator and cold chain capacity requirements over routine immunization baselines. Pandemic vaccination campaigns would add volume to national-level stores already at their limits, but sufficient capacity exists at subnational levels. Immediate attention to strengthening immunization systems is essential to support pandemic responses. FUNDING: None.
RESUMO
The 2016 mid-term review of the Global Measles-Rubella Strategic Plan 2012-20 for achieving measles-rubella elimination concluded that the full potential of strategies and activities to strengthen routine immunization (RI) service delivery had not been met. In December 2017, we contacted WHO and partner agency immunization staff in all six WHO Regions who identified 23 countries working on measles or rubella elimination that have implemented examples of recommended activities to improve RI, adapted to their needs. Among those examples, opportunities to strengthen RI through implementing supplementary immunization activities (SIAs) were reported most frequently, including advocacy for immunization and educational activities targeted at the public and skills training targeted at health professionals. The expansion of cold chain capacity to accommodate supplies required for SIAs facilitated widening RI service delivery to reach more communities, introduce new vaccines, and reduce the risk of vaccine stock-outs. Substantial numbers of under-vaccinated children, according to the national immunization schedule, have been identified during SIAs, but it is not possible to confirm whether these children actually received missing RI doses. Micro-planning exercises for SIAs have generated data that permitted the revision of catchment populations for fixed site and outreach RI services. Some countries reported using the opportunity afforded by measles/rubella elimination to strengthen overall vaccine-preventable disease surveillance and outbreak preparedness and to introduce mandatory school-entry vaccination requirements covering other vaccines in addition to measles and rubella. Unfortunately, we were unable to obtain information regarding the cost, impact or sustainability of these activities. The evaluation of the many other strategies that have been deployed in recent years to strengthen RI systems and raise vaccination coverage was beyond the scope of this survey. We conclude by providing recommendations to encourage more countries to adapt and implement a comprehensive set of RI-strengthening activities in association with the MR elimination goal.
Assuntos
Erradicação de Doenças , Programas de Imunização/organização & administração , Sarampo/prevenção & controle , Rubéola (Sarampo Alemão)/prevenção & controle , Adolescente , Criança , Pré-Escolar , Surtos de Doenças/prevenção & controle , Feminino , Pessoal de Saúde , Humanos , Programas de Imunização/legislação & jurisprudência , Esquemas de Imunização , Masculino , Vacina contra Sarampo/administração & dosagem , Vacina contra Rubéola/administração & dosagem , Instituições Acadêmicas , Vacinação , Cobertura Vacinal/estatística & dados numéricos , Organização Mundial da SaúdeAssuntos
Surtos de Doenças/prevenção & controle , Vacina contra Sarampo/administração & dosagem , Sarampo/diagnóstico , Sarampo/mortalidade , Adolescente , Anticorpos Antivirais/análise , Líquidos Corporais/imunologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Humanos , Esquemas de Imunização , Lactente , Sarampo/imunologia , Boca/imunologia , Sensibilidade e Especificidade , Testes Sorológicos , Zâmbia/epidemiologiaRESUMO
INTRODUCTION: In seven southern African countries (Botswana, Lesotho, Malawi, Namibia, South Africa, Swaziland and Zimbabwe), following implementation of a measles mortality reduction strategy starting in 1996, the number of annually reported measles cases decreased sharply to less than one per million population during 2006-2008. However, during 2009-2010, large outbreaks occurred in these countries. In 2011, a goal for measles elimination by 2020 was set in the World Health Organization (WHO) African Region (AFR). We reviewed the implementation of the measles control strategy and measles epidemiology during the resurgence in the seven southern African countries. METHODS: Estimated coverage with routine measles vaccination, supplemental immunization activities (SIA), annually reported measles cases by country, and measles surveillance and laboratory data were analyzed using descriptive analysis. RESULTS: In the seven countries, coverage with the routine first dose of measles-containing vaccine (MCV1) decreased from 80% to 65% during 1996-2004, then increased to 84% in 2011; during 1996-2011, 79,696,523 people were reached with measles vaccination during 45 SIAs. Annually reported measles cases decreased from 61,160 cases to 60 cases and measles incidence decreased to <1 case per million during 1996-2008. During 2009-2010, large outbreaks that included cases among older children and adults were reported in all seven countries, starting in South Africa and Namibia in mid-2009 and in the other five countries by early 2010. The measles virus genotype detected was predominantly genotype B3. CONCLUSION: The measles resurgence highlighted challenges to achieving measles elimination in AFR by 2020. To achieve this goal, high two-dose measles vaccine coverage by strengthening routine immunization systems and conducting timely SIAs targeting expanded age groups, potentially including young adults, and maintaining outbreak preparedness to rapidly respond to outbreaks will be needed.