WC-rBS (marketed as "Dukoral") is a monovalent inactivated vaccine containing killed whole cells of V. cholerae O1 plus additional recombinant cholera toxin B subunit. BivWC (marketed as "Shanchol" and "mORCVAX") is a bivalent inactivated vaccine containing killed whole cells of V. cholerae O1 and V. cholerae O139. mORCVAX is only available in Vietnam. Bacterial strains of both Inaba and Ogawa serotypes and of El Tor and Classical biotypes are included in the vaccine. Dukoral is taken orally with bicarbonate buffer, which protects the antigens from the gastric acid. The vaccine acts by inducing antibodies against both the bacterial components and CTB. The antibacterial intestinal antibodies prevent the bacteria from attaching to the intestinal wall, thereby impeding colonisation of V. cholerae O1. The anti-toxin intestinal antibodies prevent the cholera toxin from binding to the intestinal mucosal surface, thereby preventing the toxin-mediated diarrhoeal symptoms.A live, attenuated oral vaccine (CVD 103-HgR or Vaxchora), derived from a serogroup O1 classical Inaba strain, was approved by the US FDA in 2016. Injectable
Although rarely in use, the injected cholera vaccines are effective for people living where cholera is common. They offer some degree of protection for up to two years after a single shot, and for three to four years with annual booster. They reduce the risk of death from cholera by 50 percent in the first year after vaccination. Side effects
Both of the available types of oral vaccine are generally safe. Mild abdominal pain or diarrhea may occur. They are safe in pregnancy and in those with poor immune function.
The New England Journal of Medicine published in 2007 that orchidopexy performed before puberty resulted in a significantly reduced risk of testicular cancer than if done after puberty.The risk of malignancy in the undescended testis is four to 10 times higher than that in the general population and is about one in 80 with a unilateral undescended testis and one in 40 to one in 50 for bilateral undescended testes. The peak age for this tumor is 15–45 years old. The most common tumor developing in an undescended testis is a seminoma (65%); in contrast, after orchiopexy, seminomas represent only 30% of testicular tumors. Causes
In most full-term infant boys with cryptorchidism but no other genital abnormalities, a cause cannot be found, making this a common, sporadic, unexplained (idiopathic) birth defect. A combination of genetics, maternal health, and other environmental factors may disrupt the hormones and physical changes that influence the development of the testicles. Severely premature infants can be born before descent of testes. Low birth weight is also a known factor. A contributing role of environmental chemicals called endocrine disruptors that interfere with normal fetal hormone balance has been proposed. The Mayo Clinic lists "parents exposure to some pesticides" as a known risk factor. Risk factors may include exposure to regular alcohol consumption during pregnancy (five or more drinks per week, associated with a three-fold increase in cryptorchidism when compared to nondrinking mothers. Cigarette smoking is also a known risk factor.