Healthcare personnel acceptance and recommendations for influenza vaccine in twelve low- and middle-income countries: A pooled analysis from 2018 to 2020.

BACKGROUND: Although healthcare personnel (HCP) are targeted for influenza vaccination they typically underutilize vaccines especially in low- and middle-income countries. We explored knowledge, attitudes, and practices of HCP about seasonal influenza vaccines (SIV) to identify factors associated with and modifiable barriers to SIV uptake. METHODS: We pooled individual-level data from cross-sectional surveys about SIV conducted among health workers in 12 low- and middle- income countries during 2018-2020 (i.e., Albania, Armenia, Cote d'Ivoire, Kenya, Kyrgyzstan, Lao PDR, Lebanon, Morocco, North Macedonia, Tunisia, Tajikistan, and Uganda). Eleven countries used a standard protocol and questionnaire based on the Health Belief Model to measure perceptions of susceptibility and severity of influenza disease, benefits of, barriers to, and motivators for vaccination. We analyzed attitudes and perceptions among HCP, including acceptance of vaccine for themselves and willingness to recommend vaccines to patients, grouped by the presence/absence of a national influenza vaccination program. Models were adjusted for geographic region. RESULTS: Our analysis included 10,281 HCP from 12 countries representing four of the six World Health Organization regions: African, Eastern Mediterranean, European, and Western Pacific. The sample was distributed across low income (LIC) (3,183, 31 %), lower-middle (LMIC) (4,744, 46 %), and upper-middle income (UMIC) (2,354, 23 %) countries. Half (50 %) of the countries included in the analysis reported SIV use among HCP in both the year of and the year preceding data collection while the remainder had no influenza vaccination program for HCP. Seventy-four percent (6,341) of HCP reported that they would be willing to be vaccinated if the vaccine was provided free of charge. HCP in LICs were willing to pay prices for SIV representing a higher percentage of their country's annual health expenditure per capita (6.26 % [interquartile range, IQR: 3.13-12.52]) compared to HCP in LMICs and UMICs. HCP in countries with no SIV program were also willing to pay a higher percentage for SIV (5.01 % [IQR: 2.24-8.34]) compared to HCP in countries with SIV programs.. Most (85 %) HCP in our analysis would recommend vaccines to their patients, and those who would accept vaccines for themselves were 3 times more likely to recommend vaccines to their patients (OR 3.1 [95 % CI 1·8, 5·2]). CONCLUSION: Increasing uptake of SIV among HCP can amplify positive impacts of vaccination by increasing the likelihood that HCP recommend vaccines to their patients. Successful strategies to achieve increased uptake of vaccines include clear guidance from health authorities, interventions based on behavior change models, and access to vaccine free-of-charge.

Do pregnant persons want influenza vaccines? Knowledge, attitudes, perceptions, and practices toward influenza vaccines in 8 low- and middle-income countries.

BACKGROUND: While vaccination is the most effective way to prevent influenza infection and adverse outcomes, and despite WHO recommendations to vaccinate pregnant persons, access to seasonal influenza vaccines remains low. We explored knowledge, attitudes, and practices of pregnant persons about seasonal influenza vaccines to inform actions to improve vaccine uptake among this priority population. METHODS: We pooled individual-level data from cross-sectional surveys assessing pregnant persons' attitudes toward seasonal influenza vaccines in eight low- and middle-income countries during 2018-2019. The eight countries used a standard protocol and questionnaire to measure attitudes and intents toward influenza vaccination. We stratified by country-level (presence/absence of a national influenza vaccination program, country income group, geographic region) and individual-level factors. FINDINGS: Our analysis included 8,556 pregnant persons from eight low- and middle-income countries with and without seasonal influenza vaccination programs. Most pregnant persons (6,323, 74%) were willing to receive influenza vaccine if it was offered for free. Willingness differed by presence of an existing influenza vaccination program; acceptance was higher in countries without influenza vaccination programs (2,383, 89%) than in those with such programs (3,940, 67%, p < 0.001). INTERPRETATION: Most pregnant persons in middle-income countries, regardless of influenza vaccination program status, were willing to be vaccinated against influenza if the vaccine was provided free of charge. National investments in influenza vaccination programs may be well-received by pregnant persons, leading to averted illness both in pregnant persons themselves and in their newborn babies. FUNDING: US Centers for Disease Control and Prevention.

Costs and cost-effectiveness of influenza illness and vaccination in low- and middle-income countries: A systematic review from 2012 to 2022.

BACKGROUND: Historically, lack of data on cost-effectiveness of influenza vaccination has been identified as a barrier to vaccine use in low- and middle-income countries. We conducted a systematic review of economic evaluations describing (1) costs of influenza illness; (2) costs of influenza vaccination programs; and (3) vaccination cost-effectiveness from low- and middle-income countries to assess if gaps persist that could hinder global implementation of influenza vaccination programs. METHODS AND FINDINGS: We performed a systematic search in Medline, Embase, Cochrane Library, CINAHL, and Scopus in January 2022 and October 2023 using a combination of the following key words: "influenza" AND "cost" OR "economic." The search included studies with publication years 2012 through 2022. Studies were eligible if they (1) presented original, peer-reviewed findings on cost of illness, cost of vaccination program, or cost-effectiveness of vaccination for seasonal influenza; and (2) included data for at least 1 low- or middle-income country. We abstracted general study characteristics and data specific to each of the 3 study types. Of 54 included studies, 26 presented data on cost-effectiveness, 24 on cost-of-illness, and 5 on program costs. Represented countries were classified as upper-middle income (UMIC; n = 12), lower-middle income (LMIC; n = 7), and low-income (LIC; n = 3). The most evaluated target groups were children (n = 26 studies), older adults (n = 17), and persons with chronic medical conditions (n = 12); fewer studies evaluated pregnant persons (n = 9), healthcare workers (n = 5), and persons in congregate living settings (n = 1). Costs-of-illness were generally higher in UMICs than in LMICs/LICs; however, the highest national economic burden, as a percent of gross domestic product and national health expenditure, was reported from an LIC. Among studies that evaluated the cost-effectiveness of influenza vaccine introduction, most (88%) interpreted at least 1 scenario per target group as either cost-effective or cost-saving, based on thresholds designated in the study. Key limitations of this work included (1) heterogeneity across included studies; (2) restrictiveness of the inclusion criteria used; and (3) potential for missed influenza burden from use of sentinel surveillance systems. CONCLUSIONS: The 54 studies identified in this review suggest an increased momentum to generate economic evidence about influenza illness and vaccination from low- and middle-income countries during 2012 to 2022. However, given that we observed substantial heterogeneity, continued evaluation of the economic burden of influenza illness and costs/cost-effectiveness of influenza vaccination, particularly in LICs and among underrepresented target groups (e.g., healthcare workers and pregnant persons), is needed. Use of standardized methodology could facilitate pooling across settings and knowledge sharing to strengthen global influenza vaccination programs.

Healthcare personnel in 2016-2019 prospective cohort infrequently got vaccinated, worked while ill, and frequently used antibiotics rather than antivirals against viral influenza illnesses.

Background: Uncertainty about risk of illness and the value of influenza vaccines negatively affects vaccine uptake among persons targeted for influenza vaccination. Methods: During 2016-2019, we followed a cohort of healthcare personnel (HCP) targeted for free-of-charge influenza vaccination in five Lima hospitals to quantify risk of influenza, workplace presenteeism (coming to work despite illness), and absenteeism (taking time off from work because of illness). The HCP who developed acute respiratory illnesses (ARI) (≥1 of acute cough, runny nose, body aches, or feverishness) were tested for influenza using reverse-transcription polymerase chain reaction (rt-PCR). Findings: The cohort (2968 HCP) contributed 950,888 person-days. Only 36 (6%) of 605 HCP who participated every year were vaccinated. The HCP had 5750 ARI and 147 rt-PCR-confirmed influenza illnesses. The weighted incidence of laboratory-confirmed influenza was 10.0/100 person-years; 37% used antibiotics, and 0.7% used antivirals to treat these illnesses. The HCP with laboratory-confirmed influenza were present at work while ill for a cumulative 1187 hours. Interpretation: HCP were frequently ill and often worked rather than stayed at home while ill. Our findings suggest the need for continuing medical education about the risk of influenza and benefits of vaccination and stay-at-home-while-ill policies.

Vaccine Effectiveness of CanSino (Adv5-nCoV) Coronavirus Disease 2019 (COVID-19) Vaccine Among Childcare Workers-Mexico, March-December 2021.

BACKGROUND: Beginning in March 2021, Mexico vaccinated childcare workers with a single-dose CanSino Biologics (Adv5-nCoV) coronavirus disease 2019 (COVID-19) vaccine. Although CanSino is currently approved for use in 10 Latin American, Asian, and European countries, little information is available about its vaccine effectiveness (VE). METHODS: We evaluated CanSino VE within a childcare worker cohort that included 1408 childcare facilities. Participants were followed during March-December 2021 and tested through severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse-transcription polymerase chain reaction or rapid antigen test if they developed any symptom compatible with COVID-19. Vaccination status was obtained through worker registries. VE was calculated as 100% × (1 - hazard ratio for SARS-CoV-2 infection in fully vaccinated vs unvaccinated participants), using an Andersen-Gill model adjusted for age, sex, state, and local viral circulation. RESULTS: The cohort included 43 925 persons who were mostly (96%) female with a median age of 32 years; 37 646 (86%) were vaccinated with CanSino. During March-December 2021, 2250 (5%) participants had laboratory-confirmed COVID-19, of whom 25 were hospitalized and 6 died. Adjusted VE was 20% (95% confidence interval [CI], 10%-29%) against illness, 76% (95% CI, 42%-90%) against hospitalization, and 94% (95% CI, 66%-99%) against death. VE against illness declined from 48% (95% CI, 33%-61%) after 14-60 days following full vaccination to 20% (95% CI, 9%-31%) after 61-120 days. CONCLUSIONS: CanSino vaccine was effective at preventing COVID-19 illness and highly effective at preventing hospitalization and death. It will be useful to further evaluate duration of protection and assess the value of booster doses to prevent COVID-19 and severe outcomes.