Photo Illustration by Getty, Elena Scotti/Fusion

A new and very aggressive form of HIV has been discovered in Cuba by researchers from the University of Leuven in Belgium. The hybrid strain is what’s known as a circulating recombinant form (CRF), the result of multiple strains of HIV combining within a white blood cell and basically forming an evil Voltron strain—the strain has been dubbed CRF19. Left untreated, it can progress to full-blown AIDS within three years. Normally, untreated HIV progresses to AIDS in six to 10 years.

We chatted with one of the authors of the paper, Ricardo Khouri from the Rega Institute for Medical Research at the University of Leuven, and here’s what you need to know.

Men who have sex with men are at the highest risk.

Like all strains of HIV, the CRF19 strain has mostly affected Cuba’s gay male population. While the sample studied was 59 percent white (similar to the general population of Cuba), Khouri told Fusion that he saw no correlation between the strain and racial or ethnic background.

It all comes down to receptors.

Why does CRF19 progress so quickly? Khouri's research suggests that it enters white blood cells using a different receptor than other types of HIV—a receptor associated with accelerated disease progression. Khouri's team has also hypothesized that the new strain is so fit because it's made from superior pieces from other variants, giving it an evolutionary advantage.

Time is of the essence.

When it comes to treatment, there's good news and bad news. The good news is that CRF19 does respond to antiretroviral drugs. However, as Khouri explained: “The risk is that those patients with fast progression are diagnosed too late for therapy to be able to recover their immune system.”

Screening is the first step.

Khouri said that because the research is so new, there have not yet been any public initiatives specifically geared toward fighting CRF19. However, Cuba tracks cases of HIV infection very closely and tests for HIV frequently in the population.

It's pretty contained within Cuba.

Researchers believe CRF19 initially developed in sub-Saharan Africa, with a few cases reported there in the early nineties. And while the strain is reaching epidemic proportions in Cuba, Khouri said that, so far, it has not spread outside Cuba, with the exception of a few rare cases.