Coverage rate and adverse reactions of National Immunization Program vaccines in children with spinal muscular atrophy: a cross-sectional retrospective cohort study

Abstract

Objective: To investigate the coverage rate and the adverse reactions of National Immunization Program vaccines in children with spinal muscular atrophy (SMA). Methods: A cross-sectional retrospective cohort study was carried out from July 2016 to June 2019, 192 children (116 boys and 76 girls) with SMA registered by Capital Institute of Pediatrics and 191 healthy children (115 boys and 76 girls) vaccinated in Chaoyang Olympic Village Community Health Service Center from July 2016 to December 2018 were included. Questionnaire survey was designed to investigate the vaccination coverage rate and associated adverse events. The t-test and χ(2) test were used to compare the difference between SMA patients and healthy children. Results: The coverage rate of age-appropriate immunization in SMA children was 62.0% (119/192) in general, and were 52.2% (12/23), 55.7% (68/122), and 83.0% (39/47) for SMA type 1-3 patients, respectively (χ(2)=12.23, P=0.002). The vaccination coverage rates of Bacillus Calmette-Guerin (BCG) vaccine, the 3(rd) dose of hepatitis B, the 3(rd) dose of polio, the 3(rd) dose of diphtheria-pertussis-tetanus, the 1(st) dose of meningococcal polysaccharide group A, the 1(st) dose of measles or measles and rubella vaccine, the 1(st) dose of Japanese encephalitis vaccine, hepatitis A, measles-mumps-rubella, and group A+C meningococcal polysaccharide vaccine were 100.0% (192 cases), 94.3% (181 cases), 81.8% (157 cases), 88.5% (170 cases), 83.9% (161 cases), 76.6% (147 cases), 80.2% (154 cases), 68.2% (131 cases), 69.8% (134 cases), 54.7% (105 cases), respectively. Among the 73 patients who did not have their planned immunization completed, 57 cases (78.1%) gave up the vaccination due to parents' concern of potential aggravation of their disease, and 16 cases (21.9%) had the plan discontinued by the immunization department because of the disease. Fever, local redness and swelling were the most common side-effects after vaccination both in SMA patients and healthy children (19.8% (38/192) vs. 18.8% (36/191) , χ(2)=0.055, P=0.815). The main abnormal reactions of vaccination were rash and neurovascular edema, without significant difference between these two groups (2.6% (5/192) vs. 3.7% (7/191), χ(2)=0.355, P=0.551). The coverage rate of Influenza and pneumococcal vaccine in SMA patients were 22.4% (43 cases) and 31.8% (61 cases), respectively. The incidence of pneumonia in the SMA patients decreased from 59.0% (23/39) to 41.0% (16/39) after vaccination. And none of the Influenza vaccinated patients had the flu in the year of vaccination. Conclusions: The coverage rate of National Immunization Program vaccines in the SMA children is low, especially in type 1 SMA patients, which is mainly due to their guardians' concern of potential adverse events, even though the incidence of adverse reactions is similar in SMA patients and healthy children. Influenza and pneumococcal vaccine can reduce the risk of pneumonia and flu in children with SMA effectively.