"In the Middle East and North Africa, the HIV epidemic has been on the rise for the past decade," said Aleksandar Sasha Bodiroza, HIV/AIDS adviser at the United Nations Population Fund (UNFPA).
"The number of people needing treatment in the region has spiked from approximately 45,000 in 2001 to nearly 160,000 in 2010," Bodiroza said.
"This has put the Middle East and North Africa among the top two regions globally with the fastest growing HIV epidemic."
A United Nations report released this month said the number of people becoming infected with HIV has slowed worldwide, with AIDS-related deaths also on the decline as access to treatment becomes more widespread.
But the Arab world has been slow to catch up. Here, HIV contraction rates and AIDS-related deaths are increasing as public awareness, government response and access to adequate medical services have been slow to progress.
While there is little reliable data on the Middle East and North Africa, the United Nations estimates between 350,000 and 570,000 people live with the HIV virus in the region, home to a population estimated at more the 367 million.
One study, published recently on the open-access Public Library of Science, put infection rates among men who have sex with men at 5.7 percent in Egypt's capital Cairo -- and at 9.3 percent in the Sudanese capital Khartoum.
And while some countries have begun to take small steps towards fighting a growing but hushed problem, shame and stigma show very little sign of waning in a region where same-sex relationships and premarital sex are often a crime.
That stigma has become a fact of life for one young man in Beirut, reached through a group that provides free support for people who are HIV-positive or suffer from AIDS.
"If I were to sum it up in one word, I would say my life is one big secret," said the 29-year-old, who has known he is HIV-positive for three years.
"While I came out to my family a long time ago, this is something I have not shared with them. I could never burden them with that."
Infection is typically concentrated among high-risk groups, including injecting drug users, men who have sex with men and sex workers and their clients.
"Life for someone carrying the HIV virus is very difficult... they suffer an inability to talk about the disease freely with people who are close to them, and we have cases where individuals were kicked out of the family," said Brigitte Khoury, clinical psychologist at the American University of Beirut Medical Centre.
"So while some families do offer support, it's mainly a life of secrecy, deception and living in fear of the worst."
That fear, experts say, is often what keeps HIV-positive individuals from seeking treatment.
"Stigma and discrimination are among the primary reasons that people living with HIV or key populations at higher risk of HIV infection do not have access to essential HIV services," Bodiroza said.
"These two factors also limit the ability of governments and civil society to provide services."
Many states in the Arab world require that foreigners take an AIDS test before issuing visas or residency permits.
Making headlines this month was the case of a South African journalist who was deported from Qatar after being diagnosed with HIV and sacked by the satellite network Al-Jazeera.
Section27, a public interest legal group based in South Africa, has asked the country's delegation to the International Labor Organization to file a complaint against Qatar.
But some more liberal countries in the region have begun to publicize the problem, with a media campaign in Egypt and Lebanon hitting the airwaves and billboards last month.
The "Let's Talk" campaign, which runs until the end of December, is organised by UNFPA in partnership with the two countries' health ministries, and encourages people to be tested.
The campaign, which in Lebanon stars a former beauty queen and wildly popular band Mashrou3 Leila, also supplies a list of free and anonymous testing centers for both countries.
But despite the tentative progress, experts say governments are less likely than ever to turn their attention to the rising epidemic in a region gripped by political upheaval.
"The common thread that links all countries in the region is the impact of stigma and discrimination, which are (among) the primary reasons that people living with HIV or at-risk populations do not have access to essential services," said Bodiroza.
"Without strong leadership, it is unlikely that these issues will be fully or properly addressed."