Infeksi Saluran Pernapasan Akut (ISPA) masih menjadi salah satu penyebab utama morbiditas pada anak balita, terutama di negara berkembang. Status imunisasi dasar dan riwayat berat lahir rendah (BBLR) merupakan faktor yang secara teoritis berhubungan dengan kejadian ISPA pada anak, namun belum adanya penelitian yang secara khusus mengevaluasi efek gabungan antara status imunisasi dasar dan riwayat berat lahir terhadap kejadian ISPA pada balita. Sehingga penelitian ini bertujuan untuk menganalisis hubungan antara kedua faktor tersebut dengan kejadian ISPA pada anak usia 12–59 bulan di DKI Jakarta baik secara terpisah (independent), maupun kombinasi (gabungan) berdasarkan data Survei Kesehatan Indonesia tahun 2023 dengan menggunakan desain cross-sectional. Sampel penelitian berjumlah 711 anak usia 12–59 bulan di DKI Jakarta yang memenuhi kriteria inklusi, yaitu memiliki data lengkap pada setiap variabel yang diteliti. Variabel dependen adalah kejadian ISPA, yaitu anak yang tercatat dalam 1 bulan terakhir didiagnosis ISPA oleh tenaga kesehatan dan atau memiliki gejala demam disertai batuk/pilek/nyeri tenggorok, sedangkan variabel independen utama meliputi status imunisasi dasar, riwayat berat lahir, dan variabel gabungan status imunisasi dasar dan riwayat berat lahir. Variabel kovariat terdiri atas usia anak, status gizi, ASI eksklusif, paparan asap rokok dalam rumah, usia ibu, pendidikan ibu, status pekerjaan ibu, dan status ekonomi. Analisis dilakukan secara univariat, bivariat dan multivariat menggunakan regresi generalized linear model dengan pendekatan backward elimination. Hasil penelitian menunjukkan prevalensi ISPA pada anak usia 12–59 bulan sebesar 37,6%. Setelah mengotrol faktor perancu, anak dengan imunisasi dasar tidak lengkap memiliki prevalensi ISPA 13% lebih tinggi dibandingkan anak dengan imunisasi lengkap (aPR=1,13; 95%CI: 0,93–1,39), namun tidak bermakna secara statistik. Anak dengan riwayat BBLR juga memiliki prevalensi ISPA 33% lebih tinggi dibandingkan dengan anak yang tidak BBLR (aPR=1,33; 95%CI: 0,95–1,88). Pada analisis variabel gabungan, kelompok anak dengan imunisasi lengkap dan riwayat BBLR memiliki prevalensi ISPA tertinggi (aPR=1,62; 95%CI: 0,93–2,83) dibandingkan degan kelompok imunisasi lengkap dan tidak BBLR. Penelitian ini menyimpulkan bahwa status imunisasi dasar dan riwayat BBLR menunjukkan kecenderungan peningkatan risiko ISPA meskipun tidak bermakna secara statistik. Upaya pencegahan ISPA tetap perlu difokuskan pada peningkatan cakupan imunisasi dasar dan pemantauan kelompok anak dengan riwayat BBLR.

Acute Respiratory Infection (ARI) remains one of the leading causes of morbidity among children under five, particularly in developing countries. Basic immunization status and a history of low birth weight (LBW) are theoretically associated with the incidence of ARI in children; however, limited research has specifically evaluated the combined effect of these two factors on ARI among under-five children. Therefore, this study aimed to analyze the association between basic immunization status and birth weight history with the incidence of ARI among children aged 12–59 months in DKI Jakarta using data from the 2023 Indonesian Health Survey through a cross-sectional design. The study sample consisted of 711 children aged 12–59 months in DKI Jakarta who met the inclusion criteria and had complete data for all study variables. The dependent variable was the incidence of ARI, defined as a child who, within the previous month, had been diagnosed with ARI by a healthcare professional and/or experienced symptoms of fever accompanied by cough, runny nose, or sore throat. The main independent variables included basic immunization status, birth weight history, and a combined variable of basic immunization status and birth weight history. Covariates consisted of child age, nutritional status, exclusive breastfeeding, exposure to cigarette smoke inside the house, maternal age, maternal education, maternal employment status, and socioeconomic status. Data were analyzed using univariate, bivariate, stratified, and multivariate analyses with generalized linear model regression and a backward elimination approach. The results showed that the prevalence of ARI among children aged 12–59 months was 37.6%. After adjusting for potential confounders, children with incomplete basic immunization had a 13% higher prevalence of ARI compared with fully immunized children (aPR = 1.13; 95% CI: 0.93–1.39), although the association was not statistically significant. Children with a history of LBW had a 33% higher prevalence of ARI compared with those without LBW (aPR = 1.33; 95% CI: 0.95–1.88). In the combined-variable analysis, children with complete immunization and a history of LBW had the highest prevalence of ARI (aPR = 1.62; 95% CI: 0.93–2.83) compared with children who had complete immunization and no history of LBW. This study concludes that incomplete basic immunization status and a history of LBW tend to increase the risk of ARI, although the associations were not statistically significant. Efforts to prevent ARI should continue to focus on improving basic immunization coverage and monitoring children with a history of LBW.