Impact of a targeted typhoid vaccination campaign following cyclone Tomas, Republic of Fiji, 2010.
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ABSTRACT:
SUBMITTER: Scobie HM
PROVIDER: S-EPMC4047725 | biostudies-literature | 2014 Jun
REPOSITORIES: biostudies-literature
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Impact of a targeted typhoid vaccination campaign following cyclone Tomas, Republic of Fiji, 2010.
Scobie Heather M HM Nilles Eric E Kama Mike M Kool Jacob L JL Mintz Eric E Wannemuehler Kathleen A KA Hyde Terri B TB Dawainavesi Akanisi A Singh Sheetalpreet S Korovou Samuel S Jenkins Kylie K Date Kashmira K
The American journal of tropical medicine and hygiene 20140407 6
After a category 4 cyclone that caused extensive population displacement and damage to water and sanitation infrastructure in Fiji in March 2010, a typhoid vaccination campaign was conducted as part of the post-disaster response. During June-December 2010, 64,015 doses of typhoid Vi polysaccharide vaccine were administered to persons ≥ 2 years of age, primarily in cyclone-affected areas that were typhoid endemic. Annual typhoid fever incidence decreased during the post-campaign year (2011) relat ...[more]
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Project description:IntroductionHepatitis E (HEV) genotypes 1 and 2 are the common cause of jaundice and acute viral hepatitis that can cause large-scale outbreaks. HEV infection is associated with adverse fetal outcomes and case fatality risks up to 31% among pregnant women. An efficacious three-dose recombinant vaccine (Hecolin) has been licensed in China since 2011 but until 2022, had not been used for outbreak response despite a 2015 WHO recommendation. The first ever mass vaccination campaign against hepatitis E in response to an outbreak was implemented in 2022 in Bentiu internally displaced persons camp in South Sudan targeting 27,000 residents 16-40 years old, including pregnant women.MethodsWe conducted a vaccination coverage survey using simple random sampling from a sampling frame of all camp shelters following the third round of vaccination. For survey participants vaccinated in the third round in October, we asked about the onset of symptoms experienced within 72 hours of vaccination. During each of the three vaccination rounds, passive surveillance of adverse events following immunisation (AEFI) was put in place at vaccination sites and health facilities in Bentiu IDP camp.ResultsWe surveyed 1,599 individuals and found that self-reported coverage with one or more dose was 86% (95% CI 84-88%), 73% (95% CI 70-75%) with two or more doses and 58% (95% CI 55-61%) with three doses. Vaccination coverage did not differ significantly by sex or age group. We found no significant difference in coverage of at least one dose between pregnant and non-pregnant women, although coverage of at least two and three doses was 8 and 14 percentage points lower in pregnant women. The most common reasons for non-vaccination were temporary absence or unavailability, reported by 60% of unvaccinated people. Passive AEFI surveillance captured few mild AEFI, and through the survey we found that 91 (7.6%) of the 1,195 individuals reporting to have been vaccinated in October 2022 reported new symptoms starting within 72 hours after vaccination, most commonly fever, headache or fatigue.ConclusionsWe found a high coverage of at least one dose of the Hecolin vaccine following three rounds of vaccination, and no severe AEFI. The vaccine was well accepted and well tolerated in the Bentiu IDP camp community and should be considered for use in future outbreak response.
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Project description:IntroductionWorld Health Organization has prequalified the use of typhoid conjugate vaccine (TCV) in children over six months of age in typhoid endemic countries. We assessed the cost-effectiveness of introducing TCV separately for urban and rural areas of India.MethodsA decision analytic model was developed, using a societal perspective, to compare long-term costs and outcomes (3% discount rate) in a new-born cohort of 100,000 children immunized with or without TCV. Three vaccination scenarios were modelled, assuming the protective efficacy of TCV to last for 5, 10 and 15 years following immunization. Incidence of typhoid infection estimated under 'National Surveillance System for Enteric Fever' (NSSEFI)' was used. The prices of vaccine and cost of service delivery were included for vaccination arm. Both health system cost and out-of-pocket expenditures for treatment of typhoid illness and its complications was included.ResultsTCV introduction in urban areas would result in prevention of 17% to 36% typhoid cases and deaths. With exclusion of indirect costs, the incremental cost per QALY gained was ₹ 151,346 (54,730-307,975), ₹ 61,710 (-5250 to 163,283) and ₹ 45,188 (-17,069 to 141,093) for scenario 1, 2 and 3 respectively. While, with inclusion of indirect costs, all 3 scenarios were cost saving. Further, in rural areas, TCV is estimated to reduce the typhoid cases and deaths by 19% to 36%, with ICER (incremental cost per QALY gained) ranging from ₹ 2340 (1316-4370) to ₹ 3574 (2057 - 6691) thousand (inclusive of indirect costs) among the 3 vaccination scenarios.ConclusionFrom a societal perspective, introduction of TCV is a cost saving strategy in urban India. Further, due to low incidence of typhoid infection, introduction of TCV is not cost-effective in rural settings of India.
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Project description:Given recent downward trends in daily rates of COVID-19 vaccinations, it is important to reassess strategies to reach those most vulnerable. The success and efficacy of vaccination campaigns for other respiratory illnesses, such as influenza, may help inform messaging around COVID-19 vaccinations. This cross-sectional study examines the individual-level factors associated with, and the spatial distribution of, predictors of COVID-19 severity, and uptake of influenza and hepatitis B (as a negative control) vaccines across NYC. Data were obtained from the 2018 Community Health Survey (CHS), including self-reported influenza and hepatitis B vaccine uptake, diabetes, asthma, hypertension, body mass index (BMI), age, race/ethnicity, educational attainment, borough, and United Hospital Fund (UHF) neighborhood of residence. A CDC-defined COVID-19 severity risk score was created with variables available in the CHS, including diabetes, asthma, hypertension, BMI ≥ 30 kg/m2 , and age ≥65 years old. After adjustment, there was a significant positive association between COVID-19 severity risk score and influenza vaccine uptake (1: ORadj = 1.49, 95% CI 1.28-1.73; 2: ORadj = 1.99; 95% CI: 1.65-2.41; 3+: ORadj = 2.89; 95% CI: 2.32-3.60, compared to 0). Hepatitis B vaccine uptake was significantly inversely associated with COVID-19 severity risk score (1: ORadj = 0.67; 95% CI: 0.57-0.79; 2: ORadj = 0.54; 95% CI: 0.44-0.66; 3+: ORadj = 0.45; 95% CI: 0.36-0.56, compared to 0). The influenza vaccination campaign template is effective at reaching those most at risk for serious COVID-19 and, if implemented, may help reach the most vulnerable that have not yet been vaccinated against COVID-19.
| S-EPMC8662223 | biostudies-literature