In 2002, the first reported outbreak of Hepatitis A virus infection involving mostly intravenous drug users occurred in Italy.
Dr Spada and colleagues attempted a thorough evaluation of the outbreak, including epidemiological, clinical and virological analyses.
The investigators conducted an epidemiological investigation, including a case-control study.
The investigative team identified the source and the modes of Hepatitis A transmission.
Hepatitis B and C viruses and human immunodeficiency virus (HIV) coinfections were clinically analyzed.
| The only associated risk factor was contact with a jaundiced person|
|Journal of Hepatology|
Sequence analysis of the VP1/2A junction of the Hepatitis A isolates was also performed.
The team found that of the 47 symptomatic cases, 35 were injecting drug users.
The only associated risk factor was contact, not related to injecting practices, with a jaundiced person .
Of the cases, the team noted that 58% were anti-Hepatitis C positive and 5% anti-HIV positive.
The investigators observed that 3 individuals died of acute liver failure, of which 2 were Hepatitis C-coinfected alcohol abusers, with underlying liver cirrhosis.
A further 1 patient who dies was Hepatitis C/HIV-coinfected.
Hepatitis A virus-RNA was found in 15 of the 24 tested patients, and genotype IB and IIIA were detected.
Dr Spada's team commented, “Hepatitis A was probably transmitted through the fecal-oral route, although parenteral transmission cannot be excluded.”
“The high fatality rate was probably due to severe underlying liver damage.”
“The occurrence of this outbreak highlights the need for routine Hepatitis A vaccination for injecting drug users.”