Timely vaccination with valid doses in a high coverage country, Oman

Area of Science:

• Public Health
• Pediatrics
• Epidemiology

Background:

• Oman demonstrates high national immunization coverage rates.
• However, the timeliness and validity of vaccine administration require further assessment.
• This study aims to provide a comprehensive understanding of immunization program performance by evaluating these aspects.

Purpose of the Study:

• To evaluate the timeliness and validity of routine childhood vaccinations in Oman.
• To identify factors affecting vaccination timeliness and validity.
• To offer insights for improving immunization program performance.

Main Methods:

• A cross-sectional survey utilized WHO cluster sampling across all Omani governorates and districts.
• Data from 17,501 children under five were collected via the Epicollect5 app and verified with health records.
• Descriptive statistics, chi-square tests, and WHO operational definitions assessed coverage, validity, timeliness, and dropout rates.

Main Results:

• Crude vaccination coverage was high (94.4-99.9%), with 98.7% of children fully immunized.
• Only 78% of children received valid vaccinations, with invalid rates increasing with age.
• Vaccination timeliness decreased with age, showing notable delays at 18 months, and significant district-level variations were observed.

Conclusions:

• While Oman achieves high vaccination coverage, a significant proportion of children receive invalid vaccine doses.
• There is an urgent need to educate parents and healthcare providers on the importance of timely and valid vaccine administration.
• Improving assessment of mild illnesses and prompt vaccination can enhance complete and valid immunization rates.