The socioeconomic status of many of the worlds population is closely tied to malnutrition; subsequent lack of micronutrients may lead to increased risk of infection and death due to leptospirosis infection. Micronutrients such as iron, calcium, and magnesium represent important areas for future research. History
The disease was first described by Adolf Weil in 1886 when he reported an "acute infectious disease with enlargement of spleen, jaundice, and nephritis." Before Weils description, the disease was known as "rice field jaundice" in ancient Chinese text, "autumn fever", "seven-day fever", and "nanukayami fever" in Japan; in Europe and Australia, the disease was associated with certain occupations and given names such as "cane-cutters disease", "swine-herds disease", and "Schlammfieber" (mud fever). It has been known historically as "black jaundice", or "dairy farm fever" in New Zealand. Leptospirosis was postulated as the cause of an epidemic among Native Americans along the coast of what is now New England during 1616–19. The disease was most likely brought to the New World by Europeans.Leptospira was first observed in 1907 in a post mortem kidney tissue slice by Arthur Stimson using silver deposition staining technique. He called the organism Spirocheta interrogans because the bacteria resembled a question mark. In 1908, a Japanese research group led by Ryukichi Inada and Yutaka Ito first identified this bacterium as the causative agent of leptospirosis and noted its presence in rats in 1916. Japanese coal mine workers frequently contracted leptospirosis. In Japan, the organism was named Spirocheta icterohaemorrhagiae.
It produces particularly high rates of breast cancer among younger women with mutated genes, and despite being rare, 4% of women with breast cancer under age 30 have a mutation in this gene. PTEN:  Mutations cause Cowden syndrome, which produces hamartomas (benign polyps) in the colon, skin growths, and other clinical signs, as well as an increased risk for many cancers. CDH1:  Mutations are associated with lobular breast cancer and gastric cancer. STK11:  Mutations produce Peutz–Jeghers syndrome. It is extremely rare, and creates a predisposition to breast cancer, intestinal cancer, and pancreatic cancer. CHEK2:  Approximately one out of 40 northern Europeans have a mutation in this gene, making it a common mutation. It is also one of the most frequently mutated genes after BRCA among Hispanics in the United States. Considered a moderate-risk mutation, it may double or triple the carriers lifetime risk of breast cancer, and also increase the risk of colon cancer and prostate cancer. ATM:  Mutations cause ataxia telangectasia; female carriers have approximately double the normal risk of developing breast cancer. PALB2:  Studies vary in their estimate of the risk from mutations in this gene and the frequency of mutations in this gene may be different among different populations. It may be moderate risk, or as high as BRCA2.Approximately 45% of HBOC cases involve unidentified genes, or multiple genes. Prevention
People with BRCA1 and BRCA2 mutations are recommended to have a transvaginal ultrasound 1-2 times per year. Screening with CA-125 is also recommended.