12 medical conditions that can kill you in 24 hours or less

While heart attacks and strokes can, of course, lead to sudden death, when it comes to infectious diseases, many factors come into play that will determine if you get sick – and how sick you get. The good news? Infections that kill quickly are rare.

One of the world’s biggest killers, stroke kills more women than breast cancer and more men than prostate cancer, according to the Stroke Foundation. A stroke happens when a clot blocks a blood vessel in the brain (or the blood vessel ruptures), which cuts off oxygen to the brain. In the case of an ischemic stroke, clot-busting medications can be given to save your life – but typically within three hours. Find out the 6 signs of a stroke you might be ignoring.

The mosquito-borne illness can be found in parts of the world such as South America, Africa, and Asia. ‘A particular type of malaria parasite, called P. falciparum, can be life-threatening,’ says Dr. Citronberg, a director of infectious diseases in the US. He explains that the parasite quickly destroys red blood cells, which have the key role in delivering oxygen to your body tissues. If you are travelling overseas, he recommends seeing a travel medicine specialist or doctor who may recommend taking medications that prevent malaria. Check out these 10 conditions mosquitoes love – and some they don’t.

Dengue is another mosquito-borne infection that causes flu-like symptoms, and half the world’s population is at risk, according to the World Health Organisation. Symptoms include high fever, severe headache, and joint pain. However, the illness can develop into a complication called ‘severe dengue,’ which can be marked by severe abdominal pain and uncontrollable vomiting, which can turn deadly. A patient needs to seek help within 24 to 48 hours of the onset of these symptoms. ‘Unlike malaria, there is no medicine to prevent dengue. All you can do is use liberal amounts of mosquito repellent,’ says Dr. Citronberg. Read here to find out how to be less of a mosquito magnet.

Hundreds of thousands of people suffer from Sudden Cardiac Arrest each year, and without defibrillation and CPR less than a quarter survives. Unlike a heart attack, sudden cardiac death is often caused by an arrhythmia (where the heart beats abnormally). Every minute that passes between Sudden Cardiac Arrest and defibrillation is critical and reduces the chance of casualty survival by 10%.

Transmitted by the bite of an infected flea or through contact with another infected person, this ‘lung-based’ plague, which most commonly occurs in Africa, can be fatal in 18 to 24 hours if not quickly treated with antibiotics, per WHO. According to science, this is what a near-death experience feels like.

Meningococcal bacteria can cause a rare disease called meningococcemia. ‘This bacteria can circulate in the bloodstream and cause very rapid organ failure and death. I’ve seen patients come to the ER not feeling well and die eight hours later. It very aggressively destroys tissues, causes blood vessels to clot and limbs to die quickly,’ says Dr. Citronberg. ‘This is the single most feared infection,’ he says. Know that if you are without a spleen—an organ that helps protect your body from certain types of bacteria – you may be more at risk. The best treatment is actually prevention with vaccination, he says.

Ingesting food or water contaminated with the Vibrio cholerae bacteria can lead to watery diarrhea and severe dehydration. According to WHO, it can cause shock and kill someone within hours. An oral rehydration solution or IV fluids are necessary to treat the illness.

This life-threatening complication of diabetes (most often type 1) occurs when levels are so low that the body breaks down fat into ketones, which build up and make blood acidic. A headache, muscle stiffness, nausea, and rapid breathing are just some of the symptoms. Treatment – insulin and fluids – needs to be given promptly, or you can suffer from cerebral edema, cardiac arrest, or kidney failure. There’s a lot of misinformation surrounding diabetes. Read here to separate the myths from the truth.

Also called ‘flesh-eating strep infection’ or necrotising fasciitis, the infection is caused by a strain of the bacteria related to strep throat, says Dr. Citronberg. ‘A break in the skin via a cut can introduce bacteria that causes a rapidly progressive infection,’ he says. ‘It may start as a red bump, and in a few hours you can almost literally watch it spread in front of your eyes.’ For instance, if it starts on your foot, it would spread up your leg. Treatment involves quick identification, followed by antibiotics and surgery to remove the affected tissue. Just as with meningococcal bacteria, those without a spleen may be more at risk.

A bacterial infection coursing through your blood (sepsis, which is often associated with the bacteria that cause meningitis) can cause blood pressure to plummet, a condition called septic shock. If discovered, patients should head to the ICU, as prompt treatment is key. For every hour after that, the rate of survival decreases by 7.6 percent. Find out 18 ways to keep your blood pressure in check.