Burden of disease and associated complications of hepatitis a in children and adults in Mexico: A retrospective database study

BACKGROUND: Hepatitis A virus (HAV) infection is a leading cause of viral hepatitis in children, yet the HAV vaccine is not included in the national immunization program (NIP) in Mexico. This study addresses an identified evidence gap of the burden of hepatitis A disease, complications, and associated costs in Mexico by analyzing surveillance and healthcare data. Data review included disease morbidity (incidence and hospitalization), mortality, and healthcare resource utilization costs. METHODS: In this observational, retrospective database study, we conducted a systematic screening, extraction, and analysis of outcome data from the national surveillance system in Mexico from January 2000 to December 2019. RESULTS: During the analysis period (2000–2019), the average incidence rate/year of HAV cases was 14.7 (5.4–21.5) per 100,000 inhabitants. Children 1–9 years of age (YoA) had the highest average incidence rate/year with 47.8 (14.7–74.5). The average hospitalization rate/year due to HAV infection was 5.8% (2.9–9.6%). Although the highest burden of HAV continued to be in children (1–9 YoA), an increase in incidence and hospitalizations (with complications) in older age groups (≥ 10–64 YoA) was observed. The annual average fatality rate was estimated to be 0.44% (0.26–0.83%) of which 28.8% of deaths were concentrated in adults ≥ 65 YoA. The total direct costs of medical attention due to HAV and related complications were estimated at $382 million Mexican pesos. CONCLUSION: The overall results suggest an uptrend in HAV infections in adolescents/adults compared to children in Mexico. Therefore, as the overall incidence risk of HAV infection decreases, the mean age of infection increases. This consequently increases the risk of severity and complications in older age groups, thus increasing the demand for healthcare resources. Our findings provide evidence for including the inactivated HAV vaccine in the Mexican NIP.