TITLE:
Effectiveness of COVID-19 Vaccine Doses in Children: Case of Lake Region Economic Bloc-Kenya
AUTHORS:
Shem Otoi Sam, Naomy Onyuka, Michael Audi, Khama Rogo
KEYWORDS:
Children Vaccination, Doses, Effectiveness
JOURNAL NAME:
Open Journal of Modelling and Simulation,
Vol.11 No.3,
July
31,
2023
ABSTRACT: Introduction: Vaccination of children has experienced delays due to
paucity of information regarding safety, effectiveness, immunogenicity, and
reactogenicity. Age wise approval prioritized 12 - 17
years and later 5 - 11 years. Those below 5
years possess na?ve immunity and not considered. In Lake Region Economic Bloc
children aged 12 - 17 variably received 1, 2,
and 3 doses of vaccine. This analysis looks into effectiveness of the doses
administered. Method: Data providers from 84 LREB facilities submitted
patients’ vaccination data to Power BI supported dashboard between June 24,
2021 and July 30, 2022. Data of 12 - 17 years old was mined, analyzed and
visualized. Sample sizes considered for analysis were 0 dose, n = 8132; 1 dose, n = 271; 2
doses, n = 402, and 3 doses, n = 90. Data used in the analysis was facility
operational and not from experimental design. Relative risk analysis of
children who received 0, 1, 2, and 3 doses was done using Odds Ratio run on R
software. Results: The relative risk of infection to a child with one
dose against unvaccinated counterpart is 0.92 (95% CI, 0.61 - 1.43).
Likewise the relative risk of infection to a child aged 12 - 17 years with 2 doses against another who received
no dose is 0.87 (95% CI, 0.63 - 1.24). A child with 3
doses is 46% (95% CI, 27% - 84%) less likely to get
infected compared to another not vaccinated. Also, the relative risk between
having 2 doses and 1 dose for a child aged 12 - 17
years is 0.95 (95%
CI, 0.55 - 1.6). For the same age
group the relative risk of having 3 doses of vaccines against 1 dose is 51%
(95% CI, 26% - 100%). In addition, a
child who receives 3
doses of vaccine is 53% (95% CI, 28% - 100%)
less likely to experience breakthrough infection compared to another with 2
doses. Whereas 1st dose offers (5%) marginal protection advantage
over the 2nd dose, the 3r dose offers 49% and 47% more protection
over 1st and 2nd doses, respectively, because of
incremental reduced risk of infection gained from previous doses. During the
period, 15 children at risk were admitted with COVID-19 infections in various
regional hospitals, one had 3 doses but confounded with severe comorbidity. Conclusion: We found that 2nd dose had marginal protection over the 1st dose. However, the 3rd dose offers extensive protection compared to 1st and 2nd doses, and protects more against hospitalization. Children
at risk should receive 3 doses of vaccines.