evaluating vaccination delay in infants during covid-19 outbreak in yazd

Background: one of the potential consequences of covid-19 is the interruption of childhood vaccination. the aim of this study is to investigate the frequency of vaccination delay in children during the covid-19 outbreak in yazd, iran. methods: in this cross-sectional study in 2020, 667 children living in yazd were enrolled through multi-stage sampling method. date of birth, vaccination dates of 2-, 4-, and 6- months of age, gender, family size, birth order and municipal area were extracted from the integrated system information block (sib) system. data were analyzed using spss software version 22.results: among 667 infants, 322 (48.3%) were girls and 345 (51.7%) were boys. in total, 53.5% of children had delay in vaccination at 2-month of age, 54%, at 4-month, and 45% at 6-month regarding vaccination appointment. moreover, the dangerous delay was 3% in vaccination rounds for 2-month-olds, 5.4% for 4-month-olds, and 1.7% for 6-month-olds. at all the three appointments, there was a statistically significant difference between both the family size (p-value: 0.025, 0.017 and 0.004, respectively) and birth order (p-value: 0.015, 0.007 and 0.013, respectively) regarding vaccination delay. conclusion: despite the high frequency of one or more than one day delay for 2-, 4-, and 6-month-old infants regarding vaccination appointments, dangerous delay in the mentioned times was relatively infrequent. meanwhile, family size and birth order were two influential factors respecting vaccination delay in children. it is essential to raise awareness among families, particularly those with larger size and higher number of children about the importance of timely vaccination.