Spread of hepatitis C pinpointed

Scientists say they’ve, for the primary time, worked out the pattern of spread of hepatitis C, showing early diagnosis is essential to preventing epidemics.

A study in injecting drug users in Greece indicated that every infected person spread the disease to twenty others – 10 of those within the first two years.

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

Globally as much as 180 million people live with the virus, most are unaware that they’ve it.

Those infected don’t develop symptoms for as much as two decades and spread it to others without realising.

Study leader Dr Gkikas Magiorkinis, from Oxford University, said when people were infected with something along with flu it was really easy to see where it had come from, because people knew they were infected within days.

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

Genetic signature

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

But to produce more detail on the way it spreads, in addition they included genetic information at the virus taken from 100 samples.

Plugging the main points right into a computer model, they calculated that injecting drug users were “super-spreaders”, each transmitting the virus to twenty people.

Most importantly they found that the majority of the transmissions occurred inside the first couple of years, they report in PLoS Computational Biology.

The researchers said that folks were more infectious at inside the early days of catching hepatitis C because they’d higher levels of virus.

The evidence they’ve produced suggests programmes targeting the diagnosis and treatment of hepatitis C in high-risk groups as early as possible would prevent many new infections and associated health care costs a few years down the road.

About 20% of these infected will develop cancer or liver scarring after two decades of infection, at which point the sole treatment is liver transplantation, which costs about £100,000 ($160,000).

Dr Magiorkinis, who did the work in collaboration with the University of Athens and Imperial College London, said the model had helped build a “solid argument” to enhance early diagnosis and antiviral treatment in drug users.

“Figuring out what number of people usually are infected by each super-spreader of Hepatitis C, in addition how soon they are going to be infected, was a puzzle for over two decades,” he said.

“Our research has resolved this issue and paves the style for a modelling study to teach what sort of public health interventions could really make a difference.”

He added the approach would be useful in other infections equivalent to HIV.

HIV in gay men ‘refuses to fall’

By James Gallagher Health and science reporter, BBC News

Huge improvements in treating and testing for HIV have didn’t curb infections in gay and bisexual men in England and Wales, a study suggests.

New infections were static at about 2,300 a year between 2001 and 2010, despite rises in early diagnosis and much more people taking medication.

Scientists, writing within the Lancet Infectious Diseases, said there have been a return of risky sexual practice.

Campaigners said there have been “real challenges” in HIV prevention.

There is concern concerning the spread of HIV in men who’ve sex with other men. The Health Protection Agency’s latest report said HIV had reached an “all-time high” during this group, with increasingly more new cases reported per annum.

Infections

Working out the collection of new infections yearly is complicated, as a lot of people are undiagnosed and there is mostly a long delay between someone being infected and determining.

Researchers on the Medical Research Council Biostatistics Unit, in Cambridge, estimated when people were infected in response to the state in their immune system.

Their study showed little difference between the spread of HIV in 2001 and 2010.

“We found the selection of new infections remained quite stable over the last decade, there has been no evidence of a decline,” researcher Dr Daniela De Angelis told the BBC.

In that point the choice of gay or bisexual men being tested in clinics went from 16,000 to 59,000 a year, the time from infection to diagnosis fell from four years to only over three and the numbers taking antiretroviral therapy went from 69% to 80%.

Unsafe sex

Dr De Angelis said: “Perhaps a resurgence of unsafe sexual practice can be fuelling the spread of HIV or maybe testing isn’t very targeted.”

The Health Protection Agency said it was “seriously concerned” in regards to the level of transmission and that unsafe sex was “one of the most plausible explanation” for the findings.

The organisation’s head of HIV surveillance, Dr Valerie Delpech, said: “Men who’ve sex with men should get an HIV and STI [sexually transmitted infections] screen a minimum of annually, and each three months if having unprotected sex with new or casual partners – and we urge clinicians to take every opportunity to provide the test to this group.”

Sir Nick Partridge, the executive executive at Terrence Higgins Trust, which campaigns on sexual health, said: “These findings highlight the genuine challenges faced by HIV prevention work, which need much greater attention.”

He said that spending on safer sex campaigns had “fallen dramatically” over the last 10 years and “we must challenge the assumptions some gay men make about HIV and re-energise gay communities to tackle a genuine and growing threat to their sexual health”.

Yusef Azad, the director of policy on the National Aids Trust, said: “Around seven gay or bisexual men an afternoon within the UK are becoming HIV.

“Prevention services thus far were under-resourced, and not using a clear specialize in outcomes or effectiveness.

“They sometimes don’t address the cultural and structural drivers of HIV transmission amongst gay and bisexual men – including drug use, mental health issues and the gay scene.”