Acute hepatitis B notification rates in Flanders, Belgium, 2009 to 2017

Area of Science:

• Public Health
• Infectious Disease Epidemiology
• Vaccinology

Background:

• Belgium implemented universal infant hepatitis B vaccination and a catch-up program for 10-13 year olds in 1999.
• The study focuses on Flanders, a region with historically low hepatitis B endemicity.

Purpose of the Study:

• To assess the impact of hepatitis B prevention and control strategies on acute hepatitis B notification rates.
• To analyze trends in hepatitis B notification rates across different age groups and demographic populations in Flanders from 2009 to 2017.

Main Methods:

• An observational study utilizing mandatory hepatitis B notifications to the Agency for Care and Health in Flanders.
• Collection of demographic data and identification of risk factors associated with acute hepatitis B cases.
• Analysis of notification rates per 100,000 population over the study period (2009-2017).

Main Results:

• Acute hepatitis B notification rates in Flanders declined from 1.6 to 0.7 per 100,000 population between 2009 and 2017.
• Significant decreases were observed across all age groups, including a notable drop in young children (0-4 years).
• Sexual activity was the primary transmission route (30.7%), with an increasing trend in men who have sex with men (MSM) post-2014; five cases of mother-to-child transmission were reported.

Conclusions:

• Current hepatitis B prevention and control strategies have been effective in lowering overall notification rates in Flanders.
• There is an ongoing need for intensified prevention and control measures targeting specific adult risk groups, particularly MSM, to address persistent transmission routes.