By Tia Ghose, Staff Writer

Published: 09/27/2013 12:07 PM EDT on LiveScience


Bubonic plague, the deadly scourge that wiped out half of Europe during the Middle Ages, still lurks in pockets of the globe, new research suggests.


Although plague is now rare in Europe, it recently sickened more than 10,000 people in Congo over a decade, and cases still occasionally emerge in the Western United States, according to a study published Sept. 16 in the American Journal of Tropical Medicine and Hygiene.


The plague bacteria, Yersinia pestis, had lain dormant[1] in China's Gobi Desert for centuries. But in the 1300s, it emerged with a vengeance, fanning out via trade routes from Asia to Europe and killing millions of people along the way. The plague was transmitted by fleas harbored by rats, which flourished in the overcrowded, filthy cities of the Middle Ages. By the end of the 1500s, between a third and half of Europe's population had died from the Black Death. [Pictures of a Killer: Plague Gallery[2] ]


Even during the 1900s, the plague still killed millions of people, but since then, the advent of better hygiene in cities and swift treatment with antibiotics has reduced this erstwhile killer into a rare disease.


Still present


Still, plague outbreaks still flare up[3] around the world.



According to the new study, which tallied the reported cases of plague around the world between 2000 and 2009, more than 20,000 people became infected during that time. People contracted the disease via rodents, bad camel meat and sick herding dogs, the report said. Cases in Libya and Algeria re-emerged after decades of absence.


The biggest burden was in Africa: in Congo 10,581 people contracted plague, followed by Madagascar with 7,182 cases and Zambia with 1,309 cases.


"These events, although showing progress, suggest that plague will persist in rodent reservoirs mostly in African countries burdened by poverty and civil unrest, causing death when patients fail to receive prompt antimicrobial treatment," the authors wrote in their paper.


In the United States during that time period, 56 people contracted the plague and seven died. The cases occurred mainly because plague has become endemic in squirrels and wild rodents in the American West. Two of the fatalities were scientists: one who had conducted an autopsy on a wild mountain lion[4] , and another who worked with plague bacteria in the lab.


Despite being a hotbed of plague in times past, Europe logged very few cases of the disease in the past decade. That may be because European cities keep their rodent populations in check, so the potential hosts for plague aren't as prevalent, the researchers said.


Follow Tia Ghose on Twitter[5] and Google+ [6] . Follow LiveScience @livescience [7] , Facebook [8] & Google+ [9] . Original article on LiveScience [10] .



Copyright 2013 LiveScience, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. ]]>

Also on HuffPost:




Loading Slideshow...



  • Bubonic Plague


    Yes, the black plague -- responsible for <a href="http://www.smithsonianmag.com/people-places/mall_aug99.html?c=y&page=2" target="_hplink">killing 56 million people in Europe the 14th century</a> -- is still around, but it isn't as deadly or prevalent as it was in Medieval times. Dr. Robert Gaynes, an infectious disease expert at Emory University and author of the book <a href="http://estore.asm.org/viewItemDetails.asp?ItemID=1036" target="_hplink">Germ Theory: Medical Pioneers in Infectious Diseases</a>, said that people contract the disease when they gain access to previously undistrubed ecosystems, thereby making "these types of diseases become evident as a result of animal contact."

    These days, the disease is most commonly spread by bites from fleas that are infected with Yersinia pestis. When the bacteria enters into a person's skin, it leads to headache, chills, and <a href="http://www.bt.cdc.gov/agent/plague/factsheet.asp" target="_hplink">swollen lymph glands</a>, according to the CDC. Early <a href="http://www.bt.cdc.gov/agent/plague/factsheet.asp" target="_hplink">treatment with antibiotics</a> is essential for survival, as the disease can cause respiratory failure and shock if left untreated.

    Every year, about 1,000 to 3,000 <a href="http://healthland.time.com/2011/05/10/first-case-of-bubonic-plague-in-2011-appears-in-new-mexico/" target="_hplink">bubonic plague cases</a> occur around the world, with 10 to 20 of those cases in the United States, <em>TIME</em> reported. The first 2011 case of bubonic plague was confirmed in May in a New Mexico man.

    The reason is murky for why black plague seems to be less deadly today than in the Medieval times, Weinberg said, but it probably has to do with more rats and unclean living conditions back then, as well as a lack of appropriate medicines. In addition, the bacteria back then may be different from the current form, he added.




  • Scarlet Fever


    <a href="http://www.medicinenet.com/scarlet_fever/article.htm#history" target="_hplink">Scarlet fever</a> was among the rash of diseases that commonly afflicted people in the 19th century (alongside yellow fever, rubella and measles), according to MedicineNet. Scarlet fever most often afflicts children, causing rash and fever.

    Fortunately, scarlet fever is a lot less common today than it was centuries ago, but it still can be deadly. Today, we now know that scarlet fever is just a form of group A streptococcus (strep), Weinberg said. But instead of just turning into a regular case of strep throat, scarlet fever manifests as a red skin rash.

    With antibiotics, the disease is easily treated, though complications can occur that <a href="http://www.medicinenet.com/scarlet_fever/article.htm#history" target="_hplink">can lead to sepsis</a> (bacteria in the blood, tissue or bone), according to MedicineNet. Just this summer, Reuters reported that a Hong Kong kindergarten was closed after tests revealed that a child there may have <a href="http://www.reuters.com/article/2011/06/21/us-scarletfever-china-idUSTRE75K14Q20110621" target="_hplink">died from scarlet fever</a>. Scarlet fever is relatively common in that part of the world, but this year a Hong Kong health department spokesman told Reuters that there seem to be more cases of it this year than in past years.




  • Whooping Cough


    <a href="http://articles.sfgate.com/2011-09-20/bay-area/30178479_1_whooping-cough-booster-shots-childhood-vaccine" target="_hplink">Whooping cough</a>, caused by the Bordetella pertussis bacteria, was a common illness among children in the early 1900s, according to HealthCentral. However, when the vaccine for whooping cough was introduced in the 1940s, cases dropped. But while whooping cough cases are still dramatically lower than 50 years ago, there are still cases that persist today possibly because the vaccine against the disease doesn't provide lasting protection later in life, Weinberg said.

    Another reason is that older people seem to be able to carry whooping cough in their throats without actually getting sick (due to being vaccinated at a younger age), but that whooping cough is then passed on to infants who haven't yet been vaccinated against the disease, Gaynes said.

    "This problem has led to a recent recommendation by [the] CDC to have adults get TDAP once as adults (it contains pertussis in the vaccine) and not just a tetanus booster, which is needed every ten years," Gaynes told HuffPost.

    Recent research presented just last month shows that the <a href="http://articles.sfgate.com/2011-09-20/bay-area/30178479_1_whooping-cough-booster-shots-childhood-vaccine" target="_hplink">protection from the whooping cough vaccine</a> is decreased dramatically once a child reaches age 8 or 9, the <em>San Francisco Chronicle</em> reported.

    <a href="http://www.cdc.gov/features/pertussis/" target="_hplink">Whooping cough is very contagious</a> -- spread by cough and sneezing -- and is so named because of the sound people who have it make when they cough. Last year, 27,550 people had whooping cough in the United States, according to the CDC. The disease is the deadliest for babies, as it can lead to pneumonia, convulsions and even death.




  • Polio


    Polio, the paralysis-causing disease that afflicted former president Franklin D. Roosevelt, isn't completely gone from the world today. However, it has been eliminated from the western world, Weinberg said. The Mayo Clinic reports that the last known <a href="http://www.mayoclinic.com/health/polio/DS00572" target="_hplink">case of polio in the U.S.</a> was in 1979.

    Polio is still present in <a href="http://www.who.int/mediacentre/factsheets/fs114/en/" target="_hplink">Afghanistan, Pakistan, India and Nigeria</a>, where unrest and dangerous conditions can make it more difficult to get everyone vaccinated against the disease, according to the World Health Organization. Recently, the WHO reported that a dangerous strain of polio -- called wild poliovirus type 1 -- had <a href="http://www.huffingtonpost.com/2011/09/20/polio-china-pakistan_n_971787.html" target="_hplink">made its way from Pakistan to China</a>.

    Polio<a href="http://www.mayoclinic.com/health/polio/DS00572" target="_hplink"> causes paralysis</a> and can make it hard to breathe, the Mayo Clinic reported. It can even lead to death.




  • Gout


    Gout has been known throughout history as the "<a href="http://www.bl.uk/learning/langlit/booksforcooks/1700s/1700sfood.html" target="_hplink">disease of kings</a>" and the "rich man's disease," as it was most commonly seem among the gluttonous rich in the 1700 and 1800s, according to the British Library. Gout is considered an ancient form of <a href="http://www.cdc.gov/arthritis/basics/gout.htm" target="_hplink">inflammatory arthritis</a>, and is caused by metabolic disorder that has not been properly controlled. It occurs when uric acid crystals build up in tissues and fluids, thereby leading to a red, swollen joint that is very painful, according to the Centers for Disease Control and Prevention. The condition is most common in overweight men and women who have gone through menopause.

    Gout rates have <a href="http://arthritis.webmd.com/news/20101110/gout-cases-on-the-rise-in-u-s" target="_hplink">been on the rise</a> since the 1960s, with cases doubling between 1960 and 1990 and then continuing to rise through 2008, according to WebMD. More than 8 million Americans currently have gout.

    WebMD reported that the <a href="http://arthritis.webmd.com/news/20101110/gout-cases-on-the-rise-in-u-s" target="_hplink">rise in gout cases</a> may be due to people living longer, as the condition is seen in women only after they have passed menopause. In addition, "you can go years with hyperuricemia and no symptoms. But at some point, enough uric acid accumulates to have a flare-up of gout, so if you're living longer you are more likely to reach that threshold," gout expert Dr. John S. Sundy told WebMD.

    In addition, Gaynes speculated that it may not even be that gout rates are actually rising -- rather, detection and diagnosis may have improved throughout the years.