Vox reader Burak Ova asks: What is HIV and what is AIDS? How is it transmitted? What are the prevention methods? Is there a cure?

Human immunodeficiency virus (HIV) killed millions of people every year in the early 2000s during the height of the AIDS pandemic. Now, some two decades later, scientific advancements and public health interventions have transformed one of the deadliest diseases into something manageable, where a regular dose of medication nearly prevents its spread altogether.

So you’re right to wonder whether we’ve squashed AIDS, at least to the point where people don’t have to worry about it.

HIV is a particularly tricky virus. When it infects a person, the virus infects and kills a specific type of blood cell (called a T cell) that fights infections. This weakens the immune system and also prevents the immune system from killing HIV. If left untreated, an HIV infection develops into a severe disease called acquired immunodeficiency syndrome (AIDS). At that point, the virus has completely destroyed the immune system — this makes people more susceptible to a wide range of infections with little protection.

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HIV spreads through contaminated bodily fluids, usually during sex or when people share needles. Scientists now believe that HIV first spread to humans from infected chimpanzees in Cameroon in Central Africa. The virus spread slowly and sporadically among humans, finding its way to modern-day Kinshasa, the Democratic Republic of Congo’s bustling capital city. From there, the virus went global, and in 1981, the Centers for Disease Control and Prevention first documented several cases of what would come to be known as HIV.

Since those fateful days, almost 90 million people around the world have been infected with HIV, and more than 40 million have died from the disease. At one point, almost 5 million people became infected with HIV each year, and some 2 million people died annually from it.

Today, the outcomes are much better. In 2023, some 600,000 people died from HIV, while just over 1 million people were newly infected with the disease. Scientists and public health officials have developed a slew of medications and........

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