The Lancet

Researchers conduct an MRI on a mummy from Egypt, in search of evidence of clogged arteries.

From the Andes to Alaska and ancient Egypt, people suffered from hardening of the arteries even 4,000 years ago, researchers reported on Sunday, suggesting heart disease may not be the fault of modern living, after all.

The team looked at mummies preserved in the cold or dry heat and found fully a third had clear evidence of clogged arteries. The findings, presented at a meeting of the American College of Cardiology and also published in the Lancet medical journal, build on earlier studies that looked at ancient Egyptian mummies.

Signs of artery disease in Egyptian mummies was believed to support the idea that a life of leisure, with plenty of rich food, is the main cause of heart disease. This broader study, however, found signs of heart disease in the remains of people who would have been far from wealthy or idle.

“The fact that we found similar levels of atherosclerosis in all of the different cultures we studied, all of whom had very different lifestyles and diets, suggests that atherosclerosis may have been far more common in the ancient world than previously thought,” says cardiologist Randall Thompson of of Saint Luke’s Mid America Heart Institute in Kansas City, who led the study.

“A common assumption is that the rise in levels of atherosclerosis is predominantly lifestyle-related, and that if modern humans could emulate pre-industrial or even pre-agricultural lifestyles, that atherosclerosis, or at least its clinical manifestations, would be avoided,” Thompson added.

The Lancet/Randall Thompson

This mummy shows signs of heart disease, researchers, found

“Our findings seem to cast doubt on that assumption, and at the very least, we think they suggest that our understanding of the causes of atherosclerosis is incomplete, and that it might be somehow inherent to the process of human aging.”

Thompson’s team looked at 137 different mummies, using MRI scans to find the signs of calcification that mark artery disease. Calcium builds up in the “plaques” that clog arteries, making them hard and also making it easy to spot them on scans.

The mummies came from Peru, where bodies often mummified naturally when left in cold, dry caves high in the mountains; from the southwestern U.S, where dry air can mummify bodies; from the Aleutian Islands of Alaska, where the cold can mummify remains; and from Egypt.

The Lancet/Randall Thompson

Randall Thompson of Saint Luke's Mid America Heart Institute in Kansas City and colleagues found clear signs of heart disease in a third of 137 mummies they studied from around the world.

About 38 percent of the mummies from Egypt had signs of atherosclerosis. A quarter of the mummies from Peru did, 40 percent of ancestors of Pueblo Indians from the U.S. Southwest and three out of the five Unangans from the Aleutian Islands.

“None of the cultures were known to be vegetarian. Physical activity was probably prominent in all these of civilizations without animal or vehicle transport,” the researchers wrote.

But they would have eaten very different diets. “Indigenous food plants varied greatly over the wide geographical distance between these regions of the world. Fish and game were present in all of the cultures, but protein sources varied from domesticated cattle among the Egyptians to an almost entirely marine diet among the Unangans,” the researchers wrote.

The Aleutian Islanders would have led a hard life, venturing out on kayaks to hunt seal and to fish, and they lived in underground homes to escape the extreme cold weather. Andean peoples would have been fit, and also unlikely to have lived easy lives.

What did they have in common? Probably a lot of untreated infections, the researchers said.

“All four populations lived at a time when infections would have been a common aspect of daily life and the major cause of death. Antibiotics had yet to be developed and the environment was non­hygienic.”

Doctors know that infection can be linked to heart and artery disease. One marker of heart disease is inflammation, as measured by a compound called C-reactive protein. Could infection have somehow kept arteries inflamed and prone to clogging?

“This would be consistent with the accelerated atherosclerosis experienced by modern-day patients with rheumatoid arthritis and systemic lupus erythematosus (commonly known as lupus),” the researchers wrote.

A study published in the new England Journal of Medicine in 2003 found about 37 percent of patients with lupus had atherosclerosis.

Heart disease is the No. 1 killer of Americans, causing about a quarter of all deaths. And half of these are linked to cardiovascular disease, much of it so-called hardening of the arteries, according to the Centers for Disease Control and Prevention.

It's hard to say how common atherosclerosis is in the population as compared to the mummies, because few Americans get full-body scans that would show it, but a study last year of Afghanistan and Iraq veterans who died or were killed showed 8.5 percent had atherosclerosis in or around the heart, compared to 77 percent of Korean war veterans and 45 percent of Vietnam War veterans. Doctors believe widely used medications to lower cholesterol may have been a factor in the different rates.

Related links:

• Mummies show that even rich Egyptians were in poor health  
• Egyptian mummy's curse was blocked arteries  
• Heart disease found in Egyptian mummies
• Egyptian mummy shows signs of a rare, painful disease  
• 'Maiden' Inca mummy had a lung infection  
• Hallucinogens found in Andean mummy's hair  

Daniel Streicker / ASTMH Press

Vampire bats in an abandoned mine in Huanuco, Peru. Researchers are investigating whether some Amazonian villagers may have survived rabies infections, which have a nearly 100 percent fatality rate.

Some Amazonian villagers plagued by vampire bats may have survived rabies infections — something that doctors thought was virtually impossible. The scientists' discovery opens hopes of eventually developing an effective treatment for the nearly always fatal infection.

A study of people living in remote areas of Peru shows that about one in 10 appears to have been bitten by rabid bats, but lived to tell the tale. Rabies is almost universally fatal, with only five documented cases of people surviving. Teams at the Centers for Disease Control and Prevention are now looking further to see if people may survive the deadly virus more often than had been believed.

“They were infected,” said the CDC’s Brett Petersen, an epidemiologist who worked on the study. What’s not clear is whether the people who survived infection ever actually got sick.

Any mammal can get rabies, and the disease causes horrible symptoms as the virus attacks the nervous system. It can make an animal aggressive and violent and can cause severe pain. Victims eventually fall into a coma and die when they can no longer breathe properly.

“Rabies has the highest case fatality rate of any conventional infectious disease, approaching 100 percent,” Petersen and colleagues wrote in their report, published on Wednesday in the American Journal of Tropical Medicine and Hygiene. People can survive if vaccinated immediately after a bite or other exposure to rabies, but there is no real treatment for infection, with very rare exceptions.

The CDC team and officials with Peru’s health ministry traveled to a remote Amazon region where vampire bats regularly feed on cattle and people. It took two days to reach the area by boat.

“Many of [the people] have very basic housing. There are no real barriers for entry to bats. The bats are able to enter the house and have easy access to people,” Petersen said in a telephone interview. The teams interviewed 92 people and got blood samples from 63 of them.

More than half said they had been bitten by a bat at least once and 20 percent said they were bitten more than once a year. The blood tests showed something startling -- seven people, or 11 percent of those tested, had antibodies against rabies. These immune system proteins were the type that can neutralize a virus.

“This shows evidence that these people were exposed to rabies virus previously,” said the CDC’s Amy Gilbert, an epidemiologist who led the study.

It's undetermined whether these seven people had actually become sick. Early symptoms of rabies infection aren’t always clear and can resemble those of a cold or flu. The incubation period can be as long as three months. It might be, Gilbert said, that they were bitten and got a very low dose of the virus, perhaps not enough to make them sick. More study will be needed to find out.

“We know that not all viral introductions into the body will lead to clinical illness,” Gilbert said. A lot depends on how much virus gets in, what part of the body, how deep a bite was, and perhaps if other germs got in at the same time.

What is certain is, rabies is very deadly. “We are still talking about 99.999 percent of cases, approaching 100 percent,” Gilbert said.

The scientists aren't sure the villagers are actually immune to rabies, so the CDC team is recommending that all get vaccinated.

“What we know is that they did develop an antibody response. We don’t know what level of antibodies will provide complete protection,” Petersen said.

More outbreaks of rabies have been reported in the region in recent years, he added.

Rabies was once a global scourge, but widespread vaccination has made it very rare in countries such as the United States. The vaccine is very effective if given before symptoms develop. That's why doctors urge anyone bitten by an animal get medical attention right away. Most US cases – and there are just one or two a year at most – are caused by bat bites.

Globally, the World Health Organization says 55,000 people die of rabies every year, with dogs the source of 99 percent of these fatal bites. Five people have survived documented rabies infections -- all young girls who were given a complex treatment called the "Milwaukee protocol," which involves putting them into a medical coma.

"Our results open the door to the idea that there may be some type of natural resistance or enhanced immune response in certain communities regularly exposed to the disease," said Gilbert. "This means there may be ways to develop effective treatments that can save lives in areas where rabies remains a persistent cause of death."

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Tetra-amelia syndrome is an extremely rare genetic disorder that prevents growth of limbs. She looks like one determined kid.

Mariana Bazo / Reuters

A medical worker exercises with Yovana Yumbo Ruiz, 8, diagnosed with the Tetra-amelia syndrome, during a rehabilitation session at the clinic La Luz in Lima, Nov. 29, 2011.

Mariana Bazo / Reuters

Yovana Yumbo Ruiz, 8, diagnosed with the Tetra-amelia syndrome, lies on the floor during a rehabilitation session at the clinic La Luz in Lima, Nov. 29, 2011. Dr. Luis Rubio, the head of Yovana Yumbo Ruiz's medical case, is rehabilitating her with the hope of putting a bionic arm on her in the future.

Mariana Bazo / Reuters

Yovana Yumbo Ruiz, 8, diagnosed with the Tetra-amelia syndrome, draws on the floor during a rehabilitation session at the clinic La Luz in Lima, Nov. 29, 2011.

Mariana Bazo / Reuters

Dr Luis Rubio holds Yovana Yumbo Ruiz, 8, diagnosed with the Tetra-amelia syndrome, during a rehabilitation session at the clinic La Luz in Lima, Nov. 29, 2011.

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