Havana, Feb 18 (IANS/EFE): Cuban health authorities have detected patients infected with a new strain of the human immunodeficiency virus (HIV), which progresses far quicker to acquired immune deficiency syndrome (AIDS), Cuban state television has reported.

A study conducted by the Pedro Kouri Institute of Tropical Medicine in Havana showed that in some cases HIV took between eight and ten years to advance to AIDS, while in others the same happened in less than three years, the channel reported Tuesday.

Institute spokeswoman Vivian Kouri said researchers studied three groups of patients and for the first time found a variant of the HIV strain -- known as CRF 19 and which advances more rapidly to AIDS -- circulating in Cuba.

The new variant is believed to have originated in Africa, however, its prevalence in Cuba is quite significant as it accounts for about 17 to 19 percent of patients, said Kouri.

She also said that none of the HIV strains in Cuba were found to have a higher resistance to anti-retroviral drugs and that all of them had a similar possibility of effective treatment.

However, the report warned that the rapid spread of HIV infections from the new strain would increase the risk of patients getting gravely affected by the virus without even them realising that they were infected.

In Cuba, almost 22,000 cases of HIV have been registered since the beginning of the epidemic in 1986, and more than 18,000 of those infected are still alive, according to an official data.