Making the world better, one answer at a time. Rich soil is made up of sand, silt, clay and organic matter (compost) in various stages of decomposition. Humus is the stable remains of decayed organic matter, carbon remains of unknown sorts that attach themselves to clay to improve soil structure. Humus has the ability to increase the soil's water retention, buffer PH , and helps the plant use nutrients although humus is not fertilizer but humic acids and humins.
Diseases carried by rats include, but are not limited too, the following: Bubonic plague â Rats are the primary source of plague infection in human populations. This horrific disease is spread to humans from rats by fleas. It's present in rodents throughout the western United States, and in many other parts of the world (see map).
Background. Plague is an acute, contagious, febrile illness transmitted to humans by the bite of an infected rat flea. Human-to-human transmission is rare except during epidemics of pneumonic plague. The disease is caused by the plague bacillus, rod-shaped bacteria referred to as Yersinia pestis.Yersinia is named in honor of Alexander Yersin, who successfully isolated the bacteria in 1894 during the pandemic that began in China in the 1860s.t can harbor fleas infected with Yersinia pestis, the plague bacillus. Image courtesy of the Centers for Disease Control and Prevention (CDC), Atlanta, Ga. Rock squirrel in extremis coughing blood-streaked sputum related to pneumonic plague.