Vadim Pokrovsky stunned hundreds of students at a conference in Moscow last week when he reached into his pocket and took out a condom.

"And you, the young generation, how do you protect yourselves from HIV?" said Pokrovsky, the 61-year-old head of Russia's federal AIDS centre.

"I always have a condom on me. Today even a 90-year-old can contract the virus."

The audience fell silent for a moment before breaking into applause.

Despite the efforts of activists like Pokrovsky, the total number of registered HIV cases in Russia exceeded one million in late 2015, with authorities struggling to contain an epidemic that experts say could be curbed by increased funding and more awareness campaigns.

Pokrovsky has been openly critical of the Kremlin's policies promoting traditional family values, saying they have failed to halt the spread of the deadly virus.

"In 2015 alone, some 100,000 new HIV cases were reported in Russia," Pokrovsky told AFP.

"This is a very high rate, maybe the highest in Europe."

- Faithfulness vs condoms -

The Russian government's policy focuses on treatment while neglecting prevention drives such as sex education in schools, with the number of people infected with the virus soaring as a result, say experts.

A public health campaign in Moscow last year urged people to be faithful to their partners, rather than promoting condom use.

"Young people here often don't even know what HIV is and don't understand its dangers," said Moscow-based student Darya Belimova who joined Pokrovsky to address more than a thousand young people at the conference.

The gathering was part of the "Stop HIV/AIDS" prevention campaign spanning more than 200 universities.

And although the Russian health and education ministries support "Stop HIV/AIDS", activists and volunteers say they are fighting a lonely battle against Russia's AIDS epidemic as the virus increasingly affects the heterosexual population.

The World Health Organization last year said that Russia accounted for 60 percent of all HIV diagnoses in Europe in 2014, with heterosexual sex the main route of transmission of the virus which is spread through contact with contaminated body fluids.

The number of HIV-positive minors -- which stood at 9,792 in 2015 -- has also jumped 8.5 percent compared to the previous year.

In most of these cases an HIV-positive mother transmitted the virus to the child at birth, said Pokrovsky.

"In Russia, there is not enough public financing to support the fight against HIV at a national scale, and HIV prevention programmes for drug addicts practically don't exist," he said.

- 'Foreign agents' -

There are just a few dozen NGOs working to fight the epidemic, spread across 40 Russian cities.

"For Russia, this is a very small number," Pokrovsky said.

Organisations like the Andrey Rylkov Foundation -- which runs an outreach programme for drug users in Moscow, handing out clean needles and condoms -- receive no government funding.

The vast size of the country also presents a challenge for effective prevention, with far-flung corners of the federation like Siberia particularly badly affected.

Russia also bans methadone replacement therapy for drug addicts, which would allow users to avoid injections, eliminating the risk of contracting the virus from contaminated syringes.

Many Russian NGOs -- including those working on HIV prevention among drug addicts -- have been under increased pressure since the reelection of President Vladimir Putin to a third term in 2012.

Shortly after he was sworn in once again, the government passed a law allowing authorities to brand groups engaging in broadly-defined "political activity" that receive foreign funding as "foreign agents".

The legislation was passed soon after huge anti-Putin protests rocked Moscow, and Kremlin critics see the law as a way to muzzle the strongman's critics and tighten his grip on power.

In April, a court ordered that Sotsium, an HIV prevention NGO based in the southwestern city of Saratov, be labelled "foreign agents" after it received 1.5 million rubles ($22,400) in foreign funding to conduct a survey among drug addicts and people with HIV.

"Until recently, society wasn't really aware of the magnitude of the problem," said Sergei Smirnov, vice-chair of the Foundation for Social and Cultural Initiatives, the organisation behind the "Stop HIV/AIDS" campaign.

If the growth of HIV infections remains steady until 2021, Russia will face a so-called "generalised epidemic," the foundation warns.

An epidemic becomes "generalised" when HIV prevalence exceeds one percent in pregnant women nationwide, Pokrovsky said.

"This rate now stands at 0.8 percent," he said. "But if it increases, the risk of a serious epidemic is very high."