Hepatitis A in France: Key Figures and Findings for 2020

A decrease in the number of reported cases between 2019 and 2020, most likely due to the COVID-19 pandemic

• The year 2020, marked by the emergence and subsequent pandemic of SARS-CoV-2, saw a decrease in the number of reported cases of hepatitis A in France. In fact, 411 cases of acute hepatitis A were reported in 2020 (vs. 1,277 in 2019), with a reporting rate of 0.6 per 100,000 inhabitants (vs. 2.1 per 100,000 inhabitants in 2019).

• This decrease is largely due to the sharp drop in the number of cases linked to international travel, resulting from international travel restrictions imposed during part of 2020 (Figure 4), and most likely to the implementation of public health measures in response to the COVID-19 pandemic, which limited the spread of the hepatitis A virus (hand hygiene, closure of schools and restaurants, lockdowns, curfews).

• Changes in healthcare utilization, particularly the reduced tendency to seek medical care for mild symptoms, may also have contributed to this decline in the incidence of reported cases. Consequently, such low levels have never been recorded in 14 years of surveillance through mandatory reporting (Figure 1).

In 2020, the sex ratio was 1.0 (compared to an average sex ratio of 1.3 between 2006 and 2016, and 3.6 in 2017*). In total, 51% of cases in 2020 were women (Figure 2). The average age of reported cases was 35 years (ranging from 2 to 95 years). The age group with the highest incidence in 2020 was 6 to 15 years, as is typically observed (with the exception of 2017*).

In 2020, as in previous years, jaundice was reported in the majority of reported cases (61%), and nearly half of the cases were hospitalized (48%).

Hepatitis A in Metropolitan France and the Overseas Territories

Regarding geographic distribution, the highest reporting rate was observed in the overseas department of Mayotte, as in previous years. This rate stood at 30.5 per 100,000 inhabitants in 2020.

In the rest of the country, reporting rates ranged from 0 (in 32 departments where no cases were reported in 2020) to 1.5 per 100,000 inhabitants (Tarn-et-Garonne) (Map). By way of comparison, in 2019, only 6 departments reported no cases of hepatitis A during the year.

Hepatitis A: What were the main risk exposures in 2020?

In 2020, the epidemiology of hepatitis A, heavily influenced by the COVID-19 pandemic, showed that the main risk exposures in the 2 to 6 weeks before the onset of symptoms were:

• consumption of seafood (28% of cases);

• travel outside mainland France (21%);

• living in the household of a child under 3 years of age (20% of cases) (Figure 5).

By comparison, the main risk exposures in 2019 were a trip outside mainland France (47% of cases), the presence of known hepatitis A cases among close contacts (33% of cases), and living in a household with a child under 3 years of age (22% of cases).

Figures and maps