Vaccination coverage before and after primary health care implementation and trend of target diseases in Al Hassa, Saudi Arabia.

There were two objectives of this study. The first was to determine the impact of vaccination coverage in the first year of life on the trend of the expanded program of immunization (EPI) target diseases in Al Hassa. The second was to determine the impact of primary health care (PHC) implementation in Al Hassa on vaccination coverage. A correlation matrex was computed for all the variables to determine the correlation between vaccination coverage by type of vaccine and reported cases of EPI target diseases. A negative correlation was noticed between Bacillus Calmette Guerin (BCG), Oral Polio Vaccine (OPV), Diphtheria, Pertussis and Tetanus (DPT) and measles vaccine and reported cases of corresponding diseases. This negative correlation was significant (P = 0.043) between measles vaccine and reported measles cases. The average vaccination coverage in the first year of life based on the total number of births significantly increased in 1988 and 1989 compared to the preceding four years (P < 0.01). It is concluded that with increased vaccination coverage in the first year of life against EPI target diseases, the number of reported corresponding diseases decreased, and that PHC implementation improved the vaccination coverage in Al Hassa.