Comparison of Parental Report of Influenza Vaccination to Documented Records in Children Hospitalized With Acute Respiratory Illness, 2015-2016

Parent-daughter agreement about HPV vaccination status in Kenya and Malawi

BACKGROUND

As more countries introduce the HPV vaccine, it is important to understand the validity of vaccination measures. This is especially true in low- and middle-income countries (LMICs) where public health monitoring of vaccination data may have delays or gaps, so alternative measurement approaches are often necessary. Parental report is a common approach for measuring routine childhood vaccination, but it has not been evaluated for HPV vaccination in LMICs.

METHODS

We conducted household surveys in Kenya (n = 146) and Malawi (n = 98) with parents/guardians and their daughters who were age-eligible for HPV vaccination. We compared parents'/guardians' reports of HPV vaccination status to daughters' reports; the latter was assumed to be the "gold standard" measure.

RESULTS

88 % of Kenyan parents/guardians and 82 % of Malawian parents/guardians agreed with their daughters' reported HPV vaccination status. It was more common for parents/guardians to under-report (i.e., to say their daughter was unvaccinated but the girl said she had received dose(s)) than the inverse. Agreement with one's daughter was higher among parents/guardians who reported data from vaccination cards versus using recall, and among parents/guardians who expressed more versus less confidence in their knowledge. We did not find many differences in accuracy of report by parent/guardian characteristics, although in Kenya there were small and statistically significant negative associations with parental age, household income, and more girls in the household (the latter was also significantly negatively associated with report accuracy in Malawi).

CONCLUSIONS

In countries where surveys will commonly be used to measure HPV vaccination status, we found very high agreement of parents/guardians with their daughters' reported receipt of the vaccine. These results are similar to findings from the literature about routine childhood vaccination measurement. This suggests that researchers, clinicians, and practitioners can use parent/guardian-reported HPV vaccination of their daughter as a relatively good proxy of her own reported immunization status especially in settings without universal use of vaccination cards or registries.

Concordance between parent-reported and documented COVID-19 vaccination status among hospitalized children and adolescents: Implications for vaccine effectiveness estimates, May 2021-October 2023

BACKGROUND

During the U.S. COVID-19 Public Health Emergency (PHE), healthcare providers were required to report all administered COVID-19 vaccines in Immunization Information Systems (IIS), a key data source for vaccine effectiveness (VE) evaluations. Expiration of the PHE and commercialization of COVID-19 vaccines raised concerns about IIS data completeness. Parental report is an alternative source of vaccination data but might be inaccurate.

METHODS

Using VE surveillance network data during May 2021-October 2023, we compared parent-reported and documented COVID-19 vaccine doses for patients aged 5-18 years admitted to 35 hospitals in 25 states, overall and by case/control status. We calculated percent agreement, kappa, sensitivity, specificity, and positive and negative predictive value (NPV) of parental report. We compared proportions of patients with discordant vaccination history by demographics and incident SARS-CoV-2 infection status. We estimated VE separately using parental report and independently documented sources.

RESULTS

Among 3262 patients, agreement between parent-reported and documented COVID-19 vaccination doses was 88 % (kappa = 0.77). Most discordant pairs (346/390) were because of parental over-reporting of doses. Among patients documented as unvaccinated, most (specificity = 90 %) were reported as such by parents; nearly all reported as unvaccinated by parents had no documented vaccination (NPV = 99 %). Discordance decreased with shorter admission-to-interview intervals and varied regionally from 8 % in the Midwest to 16 % in the West. Proportions of discordant reports were similar between patients with and without SARS-CoV-2 infection (11 % vs 13 %). Median days from last vaccine dose to hospital admission was 167 (IQR: 86-288). VE of two doses (99 % original formula) against COVID-19-related hospitalization was 58 % using documented sources and 60 % using parental report.

CONCLUSIONS

Parental report of COVID-19 vaccination agreed strongly with documented sources, especially among unvaccinated patients. Despite discrepancies from parental overreporting, VE estimates from both sources were similar. As reliance on parental report increases, reducing admission-to-interview time is important for accurate vaccination history.

Ascertainment of vaccination status by self-report versus source documentation: Impact on measuring COVID-19 vaccine effectiveness

BACKGROUND

During the COVID-19 pandemic, self-reported COVID-19 vaccination might facilitate rapid evaluations of vaccine effectiveness (VE) when source documentation (e.g., immunization information systems [IIS]) is not readily available. We evaluated the concordance of COVID-19 vaccination status ascertained by self-report versus source documentation and its impact on VE estimates.

METHODS

Hospitalized adults (≥18 years) admitted to 18 U.S. medical centers March-June 2021 were enrolled, including COVID-19 cases and SARS-CoV-2 negative controls. Patients were interviewed about COVID-19 vaccination. Abstractors simultaneously searched IIS, medical records, and other sources for vaccination information. To compare vaccination status by self-report and documentation, we estimated percent agreement and unweighted kappa with 95% confidence intervals (CIs). We then calculated VE in preventing COVID-19 hospitalization of full vaccination (2 doses of mRNA product ≥14 days prior to illness onset) independently using data from self-report or source documentation.

RESULTS

Of 2520 patients, 594 (24%) did not have self-reported vaccination information to assign vaccination group; these patients tended to be more severely ill. Among 1924 patients with both self-report and source documentation information, 95.0% (95% CI: 93.9-95.9%) agreement was observed, with a kappa of 0.9127 (95% CI: 0.9109-0.9145). VE was 86% (95% CI: 81-90%) by self-report data only and 85% (95% CI: 81-89%) by source documentation data only.

CONCLUSIONS

Approximately one-quarter of hospitalized patients could not provide self-report COVID-19 vaccination status. Among patients with self-report information, there was high concordance with source documented status. Self-report may be a reasonable source of COVID-19 vaccination information for timely VE assessment for public health action.

Vaccine Effectiveness Against Influenza Hospitalization and Emergency Department Visits in 2 A(H3N2) Dominant Influenza Seasons Among Children <18 Years Old-New Vaccine Surveillance Network 2016-2017 and 2017-2018

Studies have shown egg-adaptive mutations in influenza vaccine strains that might have impaired protection against circulating A(H3N2) influenza viruses during the 2016-2017 and 2017-2018 seasons. We used the test-negative design and multivariable models to assess vaccine effectiveness against influenza-associated hospitalization and emergency department visits among children (<18 years old) during the 2016-2017 and 2017-2018 seasons. Effectiveness was 71% (95% confidence interval, 59%-79%), 46% (35%-55%), and 45% (33%-55%) against A(H1N1)pdm09, A(H3N2), and B viruses respectively, across both seasons. During high-severity seasons with concerns for vaccine mismatch, vaccination offered substantial protection against severe influenza outcomes requiring hospitalization or emergency department visits among children.

Influenza clinical testing and oseltamivir treatment in hospitalized children with acute respiratory illness, 2015-2016

BACKGROUND

Antiviral treatment is recommended for all hospitalized children with suspected or confirmed influenza, regardless of their risk profile. Few data exist on adherence to these recommendations, so we sought to determine factors associated with influenza testing and antiviral treatment in children.

METHODS

Hospitalized children <18 years of age with acute respiratory illness (ARI) were enrolled through active surveillance at pediatric medical centers in seven cities between 11/1/2015 and 6/30/2016; clinical information was obtained from parent interview and chart review. We used generalized linear mixed-effects models to identify factors associated with influenza testing and antiviral treatment.

RESULTS

Of the 2299 hospitalized children with ARI enrolled during one influenza season, 51% (n = 1183) were tested clinically for influenza. Clinicians provided antiviral treatment for 61 of 117 (52%) patients with a positive influenza test versus 66 of 1066 (6%) with a negative or unknown test result. In multivariable analyses, factors associated with testing included neuromuscular disease (aOR = 5.35, 95% CI [3.58-8.01]), immunocompromised status (aOR = 2.88, 95% CI [1.66-5.01]), age (aOR = 0.93, 95% CI [0.91-0.96]), private only versus public only insurance (aOR = 0.78, 95% CI [0.63-0.98]), and chronic lung disease (aOR = 0.64, 95% CI [0.51-0.81]). Factors associated with antiviral treatment included neuromuscular disease (aOR = 1.86, 95% CI [1.04, 3.31]), immunocompromised state (aOR = 2.63, 95% CI [1.38, 4.99]), duration of illness (aOR = 0.92, 95% CI [0.84, 0.99]), and chronic lung disease (aOR = 0.60, 95% CI [0.38, 0.95]).

CONCLUSION

Approximately half of children hospitalized with influenza during the 2015-2016 influenza season were treated with antivirals. Because antiviral treatment for influenza is associated with better health outcomes, further studies of subsequent seasons would help evaluate current use of antivirals among children and better understand barriers for treatment.