A team of Spanish researchers has carried out a study – driven by the Ministry of Health, Consumption and Social Welfare – in order to establish the prevalence of antibodies against hepatitis C virus (HCV) infection in the population general Spanish, as well as the prevalence of active infection with HCV and the factors associated with these prevalences.
A study similar to the present one had already been carried out in 1996, but the data had been clearly outdated both by the passage of time and by the epidemiological and therapeutic changes that have occurred in the last 20 years. The new study was conducted between May 2017 and May 2018.
The selected population was 9,103 people aged between 2 and 80 years. These people were randomly selected in health centers (mainly primary care centers) and in some cases a screening was done by health card number to complete certain age subgroups. The objective was for the sample to be representative of Spanish society, both in terms of age and country of origin.
Taking into account that the Spanish population in 2018 was 46,720,000 people, this would allow to conclude that in Spain there would be a total of 79,424 people with active infection with HCV. This represents a significant reduction in recent years, as more than 110,000 people managed to heal between 2015 and 2018 thanks to direct action antivirals. Of the 17 cases detected in the present study, 13 were aware that they lived with HCV, from which it could be concluded that 24% of people with HCV in Spain would not know that they are infected.
Given that no case of HCV infection was found below 20 years, most of the analyzes were carried out taking into account only the 7,565 people aged between 20 and 80 years.
The prevalence of antibodies against HCV was significantly higher in men (1.24%) than in women (0.46%). This prevalence increased with age, although two important peaks were found: people between 50 and 59 years old (where the prevalence was 1.56%) and those between 70 and 80 years old (where the prevalence was 1.63). %). These two peaks correspond to two very different contexts: the extensive use of intravenous drugs during the 1980s (at the peak of 50-59 years) and the extensive use of health or public health interventions under inadequate conditions to prevent transmission of HCV such as transfusions before 1990 and / or use non-sterile syringes before 1975 (at the peak of people between 70 and 80 years old). Although the prevalence of antibodies was higher in people born outside of Spain, the difference did not reach statistically significant values.
The percentage of people aged between 20 and 80 years born outside Spain in the study was 6.4%, clearly lower than the 16% observed in the general population. This could be due to the difficulties in access to the health system of immigrants who have been interposed in recent years, especially after the entry into force of Royal Decree-Law 16/2012. As the recruitment of participants occurred in the health field, it was not possible to have data on those who can not access the health system.
The results of this study can be a very important tool in order to quantify the cost of treating all people with HCV already diagnosed and to diagnose and treat the fourth who are still unaware of it. It can also be a negotiation tool with pharmaceutical companies to reduce the price of direct-acting antivirals in exchange for diagnosing and treating a greater number of people.
On the other hand, among the opportunities missed by the study, the fact of not having registered sexual orientations or providing detailed information on the use of drugs, two very important factors in the new cases of HCV infection linked, for example, to chemsex, stand out.