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.
Salmonellosis, or salmonella, is another bacterial illness that both domestic and wild rats carry. Like leptospirosis, it is spread to humans through contact with urine and feces. In humans, salmonellosis causes gastrointestinal problems such as diarrhea, stomach cramps and fever.
Scanning electron micrograph of Yersinia pestis, which causes bubonic plague, on proventricular spines of a Xenopsylla cheopis flea. NIAID. Yersinia pestis (sometimes spelled Yersina) is the name of the bacteria that causes the bubonic plague.. pestis is primarily the cause of disease in a wide variety of rodents, including marmots, ground squirrels, gerbils, and prairie dogs, and, most famously, rats, specifically the black rat (Rattus rattus) (and almost certainly not the brown rat (R. norvegicus), despite what you might have heard).