In 1348, Pope Clement VI’s physician wrote the following as the “Black Death” hit Avignon: “It was so contagious, especially that accompanied by spitting of blood, that not only by staying together, but even by looking at one another people caught it…The father did not visit his son, nor the son the father. Charity was dead and hope was crushed.” (From Deadly Companions by Dorothy H. Crawford)
Scientists have long suspected that the bacterium Yersinia pestis,which causes bubonic plague, caused the Black Death that killed over 30% of Europe’s population in 1347 and continued to burn through Europe for the next three hundred years. Two teams of scientists reported this week that not only was Yersinia pestis definitely the microbe that caused the Black Death, but that bubonic plague has its roots in China, where it has lived in fleas in the wild rodent populations for thousands of years. Humans are an accidental host of this deadly bacterium, but in three major waves it decimated the populations of Europe, Asia and Africa, causing the most dramatic fall in population ever recorded.
Y. pestis is carried by fleas, who are made ravenous by the bacteria and jump from rodent (often rats) to rodent looking for warm blood and injecting thousands of bacteria with each bite. As rats die, the fleas sense the cooling blood and jump to new victims. If the victim is human, they will probably be infected with bubonic plague and, if untreated with antibiotics (which they didn’t have during the middle ages), stand a pretty good chance of dying. If the infection goes to the victim’s lungs and they infect someone else by coughing on them, that person is as good as dead.
Bubonic plague eventually died out in Europe, but not before infected rats stowed away on ships traveling to the United States in the 1890s, where they arrived in San Francisco and quickly infected the squirrel population. Over 50 kinds of rodents in the Western U.S., Canada and Mexico are potential hosts for Y. pestisis and the bacteria is still surviving in these populations, from California to Colorado. Fortunately, as long as the disease stays in wild rodents and away from urban rat populations, it probably won’t cause many cases of plague in the U.S.A. (there were only 15 in 2006.) We’re lucky to live in the age of antibiotics, which can treat most cases of plague today.
What should you do if you don’t want to catch the “Black Death?” Avoid wild rodents like the plague.
Sandwiched between oil spills and militant lairs in the paper this morning, I found hope for millions of people.
The New York Times reported that a new drug therapy offers hope to children and adults suffering from a relatively common genetic flaw that causes autism and mild to severe retardation. According to the article, one child in five thousand is born with Fragile X Syndrome, which is the most common inherited cause of mental retardation. (Down Syndrome is not inherited.) Fragile X patients appear to experience an overload of brain signalling and the drug, manufactured by Novartis, appears to help by slowing down this excessive talk between brain cells. Researcher hope this will allow patients to form memories, learn and develop more normally. If further studies bolster these initial trials, performed in adults, the drug may also hope for patients with autism not caused by Fragile X. “This is perhaps the most promising therapeutic discovery ever for a gene-based behavioral disease,” said Dr. Edward M. Scolnick.
I found lots of interesting tidbits in today’s Science Times!
In science news, my son was fascinated to learn that ABE, a pioneering undersea robotic explorer, appears to have implodedunder about 10,000 feet of water while searching for hydrothermal vents in the sea of southern Chile. We also read that “Fearless Felix” Baumgartner is going to jump from a helium balloon in the stratosphere, 120,000 feet above earth in an attempt to be the first skydiver to break the speed of sound.
In health news, The Science Times today tells us that a study showed that when soda prices went up, consumers health improved. (Not that surprising, really.) There was an interesting article about new research showing that taking an anti-inflammatory related to aspirin helped Type 2 diabetes patients manage their disease and even lower their blood sugar. This seems to be further evidence that inflammation plays a role in diabetes. There is also a good article about Dr. Thomas Frieden,the new director of the Centers for Disease Control and Prevention in Alanta. I was happy to read that he’s reorganizing the agency to give scientists better access to top leadership and popping into research labs on a regular basis to see what’s going on.