METHODS: Vaccination impact was investigated with an age-structured, host-vector, serotype-specific compartmental model. Parameters related to vaccine efficacy and levels of dengue transmission were estimated using data collected during the phase III efficacy studies. Several vaccination programs, including routine vaccination at different ages with and without large catch-up campaigns, were investigated.
RESULTS: All vaccination programs explored translated into significant reductions in dengue cases at the population level over the first 10years following vaccine introduction and beyond. The most efficient age for vaccination varied according to transmission intensity and 9years was close to the most efficient age across all settings. The combination of routine vaccination and large catch-up campaigns was found to enable a rapid reduction of dengue burden after vaccine introduction.
CONCLUSION: Our analysis suggests that dengue vaccination can significantly reduce the public health impact of dengue in countries where the disease is endemic.
OBJECTIVES: To assess the test-retest reliability of the Parent Attitudes about Childhood Vaccines (PACV) questionnaire in Malay language; to determine the prevalence of vaccine hesitancy among parents and its associations with parents' socio-demographic characteristics.
METHODS: Forward and backward translation of PACV in Malay language was carried out. The reliability of the Malay-PACV questionnaire was tested among parents with children. The same questionnaire was used to study vaccine hesitancy among parents in a tertiary hospital in Kuala Lumpur. Information pertaining to socio-demographic characteristics, sources of information regarding vaccination and vaccine hesitancy were collected. Associations between vaccine hesitancy with socio-demographic factors were tested using Multivariable Logistic Regression.
RESULTS: The Spearman correlation coefficient and Cronbach alpha for total PACV was 0.79 (p<0.001) and 0.79 respectively. The intra-class correlation coefficients of the subscales ranged from 0.54 to 0.90 demonstrating fair to excellent reliability. A total of 63 (11.6%) parents were noted to be vaccine hesitant. In the univariate analyses, vaccine hesitancy was associated with unemployed parents, parents who were younger, had fewer children and non-Muslim. In the multivariate model, pregnant mothers expecting their first child were four times more likely to be vaccine hesitant compared to those who already had one or more children (aOR: 3.91, 95% CI: 1.74-8.79) and unemployed parents were also more likely to be vaccine hesitant (aOR: 1.97, 95% CI: 1.08-3.59). The internet (65.6%) was the main source of information on vaccination followed by brochures (56.9%).
CONCLUSION: The Malay-PACV questionnaire is reliable to be used. The prevalence of vaccine hesitancy among the multi-ethnic Malaysians was comparable with other populations. Pregnant mothers expecting their first child and unemployed parents were found to be more vaccine hesitant.
METHODS: A survey was distributed to national experts in infectious diseases and health-care authorities (March 2015-April 2016), collecting information on local recommendations, costs and perception of barriers for implementation.
RESULTS: Forty-nine of the 79 contacted countries (62% response rate) provided a complete analyzable data. RVI was recommended in 27/49 countries (55%). Although five countries have recommended RVI since 2006, a large number (16, 33%) included RVI in a National Immunization Schedule between 2012 and 2014. The costs of vaccination are covered by the government (39%), by the GAVI Alliance (10%) or public and private insurance (8%) in some countries. However, in most cases, immunization is paid by families (43%). Elevated cost of vaccine (49%) is the main barrier for implementation of RVI. High costs of vaccination (rs=-0.39, p=0.02) and coverage of expenses by families (rs=0.5, p=0.002) significantly correlate with a lower immunization rate. Limited perception of RV illness severity by the families (47%), public-health authorities (37%) or physicians (24%) and the timing of administration (16%) are further major barriers to large- scale RVI programs.
CONCLUSIONS: After 10years since its introduction, the implementation of RVI is still unacceptably low and should remain a major target for global public health. Barriers to implementation vary according to setting. Nevertheless, public health authorities should promote education for caregivers and health-care providers and interact with local health authorities in order to implement RVI.
METHODS: This retrospective population-based analysis estimated crude and standardized incidences of VLD and NLD in twelve hospitals in Brazil (n = 3), Mexico (n = 3), and Malaysia (n = 6) over a 1-year period before the introduction of the tetravalent dengue vaccine. Catchment areas were estimated using publicly available population census information and administrative data. The denominator population for incidence rates was calculated, and sensitivity analyses assessed the impact of important assumptions.
RESULTS: Total cases adjudicated as definite VLD were 5, 57, and 56 in Brazil, Mexico, and Malaysia, respectively. Total cases adjudicated as definite NLD were 103, 29, and 26 in Brazil, Mexico, and Malaysia, respectively. Crude incidence rates of cases adjudicated as definite VLD in Brazil, Mexico, and Malaysia were 1.17, 2.60, and 1.48 per 100,000 person-years, respectively. Crude incidence rates of cases adjudicated as definite NLD in Brazil, Mexico, and Malaysia were 4.45, 1.32, and 0.69 per 100,000 person-years, respectively.
CONCLUSIONS: Background incidence estimates of VLD and NLD obtained in Mexico, Brazil, and Malaysia could provide context for cases occurring after the introduction of the tetravalent dengue vaccine.