This Woman Cured Her Cancer with an Insane Method

A sharp needle breaks skin and pierces the firm, dark tumor. Millions of viruses invade deep into the deadly cancer, kickstarting an experiment that had never been attempted before – Bypassing some of the most sacred safety nets in medicine. This is the story of Dr Beata Halassy, an expert virologist from Croatia who decided to cure her own cancer. Thanks to her help, we can tell it as accurately as possible. It had been a few years since Beata had been diagnosed with breast cancer - a pretty bad one.

After a surgery to remove as much of the cancer as possible she went through four cycles of pretty harsh chemotherapy. The goal was to eliminate every last cancer cell that was still hiding in her body. And the chemo did its job – all rapidly dividing cells in Beata's body died en masse – the cells of her immune system, hair and mucosa and digestive track died in droves. We’ll spare you the details, but it was not fun. Beata was sure that if this harsh treatment would not destroy the cancer completely, then nothing would.

Unfortunately at least one cell survived. After two years it came back again and was removed again. And again it came back, stronger, bigger and now even more dangerous than before. A hard dark mass that had begun invading Beata's muscles and skin, getting ready to spread all over her body. Stage 3B. If it was allowed to succeed, her chances of survival were very slim. This is where Beata decided to take care of this cancer herself, with the support of her colleagues – because they actually had a unique mix of expertise and resources.

Her plan was as simple as it was daring: They would breed viruses that they were deeply familiar with from her lab and inject them directly into her cancer. Why Viruses Love Cancer Like many medical advances this one was discovered by accident. In the early 20th century baffled doctors observed that the tumors of some cancer patients shrank when they got virus infections like influenza or measles. Which makes perfect sense if we understand how both work.

When regular cells are infected with a virus they fight back hard and without compromise: First they slow down, calming their internal machinery so the virus has a harder time taking them over and making copies of itself. Then they scream for the immune system to send anti-virus killers – which usually means that they will be killed themselves. And, if they can, they push their self-destruct button and take the virus with them. Cancer cells are unable to use any of these defenses, exactly because of the corruption that makes them cancer.

They are unhinged and hyperactive, eating and reproducing feverishly, unable to slow down. Cancer cells also can’t really call the immune system to help them out because it is trying really hard to kill them. Successful cancers actually build a protective zone around them that hides them from immune cells or even kills them. And lastly, their self-destruct button is broken. So, viruses are a horrible enemy for cancer cells, slaying them effortlessly. But much worse, once a virus starts killing, all of the ensuing death, virus- and tumor particles attract the immune system which then happily joins the massacre.

Virotherapy became an active field of research and a big hope for beating cancer. Unfortunately it turned out that using viruses to kill cancer is way harder than initially thought. You’ve got three very complex players trying to kill each other, fighting inside a living human being that somehow has to survive. Cancer is also very much not cooperative in its own destruction and often very hard to reach, especially if it has already spread throughout the body. And in the end, you need to kill every last cell to really slay it.

Cancer is also a living, evolving entity and doesn’t look exactly the same in two people. So it is extremely difficult to find virotherapies that work in many different patients. On top of all that, cancer is typically treated with chemotherapy first – often with incredible results and great survival rates. The author of this video is only alive because of chemo, so we are not talking it down at all. But one of its most brutal side effects is that it can severely weaken your immune system. And without your immune system at its A game, virotherapy can’t work properly because it is doing most of the slaughter.

As an expert virologist with extensive experience Dr Halassy knew all of this. So she developed a plan – she would take her chances, forgo another round of chemo and keep her immune system ready to fight. Beata would engineer her own anti-cancer virus mix and do her own virotherapy. Nobody had done anything like this before. Even with all of her experience and resources, this was not going to be easy. Viruses might actually be part of the solution here.

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If you want to discover all the services NordVPN offers go to NordVPN.com/Kurzgesagt to get 4 months extra on a 2-year plan - all risk-free with NordVPN's 30-day risk-free refund guarantee. Great, that’s sorted – now back to useful viruses! Beata’s Viruses In labs viruses are usually produced by injecting them into cell cultures, letting them multiply and then purifying the mix. Creating a liquid with mostly viruses but also some cell debris and garbage.

This is good enough for most lab experiments, but would never be allowed to be used in humans. Anything that goes into our bodies has to be clinical grade, way more pure to be as safe as possible. Beata decided the risk was acceptable for her. So her next big question was which virus to inject. The main thing she was looking for was a virus that specifically attacked the cell types the cancer emerged from. Ideally it should not cause a serious disease, because surviving cancer doesn’t help if you then die of ebola.

And this virus had to have been clinically tested in humans before. So for her first virus Beata and her colleagues chose… measles. Not the wild, dangerous type that killed about 100,000 people in 2024. The weakened and pathetic version we have been using in the measles vaccines for over 40 years. Beata went to work and, together with her team, produced her first dose: A syringe filled with about 600,000 measles viruses. The plan was to get an injection every few days, for the next few weeks and monitor closely what would happen to the cancer.

And so the experiment began. The needle was pushed directly into her cancer. A dark, hard tumor, growing and thriving. At first, nothing seemed to be happening. But after the second dose of tens of thousands of viruses, the tumor suddenly exploded, almost doubling in size, and became more spikey, aggressive looking. After two more injections the tumor began to shrink and constrict. What was happening inside Beata's body? Let’s go back in time.

After the first injection the viruses could not believe their luck. They had found the most amazing hunting grounds and they went to work, infecting, killing, multiplying. Cancer cells were screaming in panic and dying by the millions. The tumor turned into a battleground, leaking the broken parts of dead cells and countless new born viruses. Until this moment the cancer had been protected by a chemical defense zone around itself, hiding from the immune system. No anti-cancer cell could cross it.

But the measles massacre shattered the protection. There is nothing that makes your immune system more aggressive than evidence of cells being killed. Death is always an emergency. And with that much death and virus parts leaking into healthy tissue Beata’s immune system suddenly jolted awake in shock. Not only was there an enormous virus infection that somehow had been able to fester … no there was something else.... A hidden archenemy, suddenly ripped from the shadows and without protection.

Beata’s immune system chose violence. Like angry angels of death, millions of immune cells invaded the tumor furiously fighting and killing viruses and cancer. This sudden influx of cells is what caused Beata’s tumour to swell so explosively. What followed was an epic and unhinged massacre. Viruses killed defenseless cancer cells, virus hunter cells gobbled up viruses and cancer killers exploded cancer cells left and right, while cancer cells still fought back and deactivated immune cells where they could.

Every few days fresh injections followed, saturating Beata’s cancer with at least 80 million viruses in total, keeping the massacre going. There was one problem though: the immune system was too good at its job – soon Beata would be totally immune against measles and likely eradicate the virus, which might end the therapy before it finished. So after a few weeks Beata started injecting a second virus: VSV, a pretty harmless relative of rabies that causes mild flu symptoms in the extremely rare cases a human catches it.

Within a day after the first VSV injection, Beata fell ill with a fever and chills. But amazingly these would remain her only side effects during the entire experiment. Her immune system was freshly offended and once again hurled itself into the tumor with new found anger. The massacre continued – as unhinged as before. After two months of injections the tumor was only a shadow of its former self – 63% smaller, it had turned soft and lost its density. And critically: it had completely stopped any advances into the muscle and skin tissue.

Now surgeons removed the weakened tumor and examined it in the lab – half of its mass was immune cells still angrily bashing cancer cells to death. Beata had beat her own cancer. To be sure no survivors could grow back her doctors treated her with additional anti-cancer drugs for a year – but at the time of the making of this video it has been six years and her cancer has not returned. It seems that Dr Halassy has cured herself for good. Why don't we treat patients more often this way?

Beata’s decision to inject herself with viruses earned her much admiration and applause but also a ton of criticism from medical ethicists – mostly because the viruses and methods she used were not approved for use in humans. Which begs the question: why is it so hard for patients like her to access experimental treatments? Well, the reality is that many things in life are not really right or wrong but exist on a trade-off slider. There is no correct decision, just which payoffs do you want to accept.

In this case, if you make medical trials easy, fast and cheap then there will be experiments that will seriously harm a few people – but on average you will make more progress, faster. Which will potentially save more lives in the end. If you make medical trials hard, very slow and expensive, on average you will harm fewer people and can be pretty confident that new therapies are pretty safe. But you also hugely slow down medical progress and even completely prevent some new therapies. In today's world the slider is firmly on this side.

So as a result, many novel cancer therapies are usually only given to people who have exhausted all other conventional therapies and whose cancer is very advanced. As a last resort of sorts. At the time of making this video, over 100 studies are actively testing viruses against cancer in humans, but the vast majority are restricted to late-stage cancers. And this slows down progress – because it means that new therapies are tested in people whose body and immune systems are already severely weakened while their cancer is at the height of its strength.

So perhaps it is time to give viruses a chance earlier in the process: when the cancer is only getting started, and the body is not yet weakened by more aggressive treatments. To be crystal clear – virotherapy is not and won’t be the cure to cancer. Cancer is hundreds of different diseases and the best therapy depends on the type, location and how far it has spread. But in the best case virotherapy could be much less toxic and as effective or better than chemo – especially in combination with other therapies.

Another weapon in our arsenal. So what can we take away from Dr Halassy’s story? Her goal was to save her own life in the face of a terminal threat. It was not without risk, but she succeeded. And in the process, she hoped to inspire more research on virotherapy as early options for patients – to save other lives like hers. But she was also in a pretty unique position to try this experiment – and since she was doing it on herself, she didn’t need to go through the processes that would usually have slowed it down or forbidden it.

In 2026, 6 years after Beata’s treatment, over a dozen studies are underway to test viruses as early-stage cancer therapies. And in our book this is hugely great news. If you want to keep learning about biology and science, we've got the perfect poster series for you! Fill your walls with knowledge every aspiring scientist should have at a glance – from our Periodic Table Poster to our World Map Poster. Or dive into complex topics like evolution and human history, packed with fascinating details you'll keep discovering over time.

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