Spread of hepatitis C pinpointed

Scientists say they have, for the first time, worked out the pattern of spread of hepatitis C, showing early diagnosis is key to preventing epidemics.

A study in injecting drug users in Greece indicated that each infected person spread the disease to 20 others - 10 of these in the first two years.

The researchers said their results would help tackle the disease's spread.

Globally up to 180 million people live with the virus, most are unaware that they have it.

Those infected do not develop symptoms for up to 20 years and spread it to others without realising.

Study leader Dr Gkikas Magiorkinis, from Oxford University, said when people were infected with something such as flu it was very easy to work out where it had come from, because people knew they were infected within days.

But with hepatitis C, no-one has been able to pin down how the virus spreads, because cases occur months or years apart.

Genetic signature
To overcome this problem, the researchers looked at four hepatitis C epidemics in Greece, using data from 943 patients collected between 1995 and 2000.

But to provide more detail on how it spreads, they also included genetic information on the virus taken from 100 samples.

Plugging the details into a computer model, they calculated that injecting drug users were "super-spreaders", each transmitting the virus to 20 other people.

Most importantly they discovered that most of the transmissions occurred in the first couple of years, they report in PLoS Computational Biology.

- BBC.co.uk