As folate is vital in the first trimester of pregnancy for healthy fetal development, the use of antifolates is strongly contraindicated in pregnancy and carries significant teratogenic risk. Low doses of methotrexate can deplete folate stores and cause side-effects that are similar to folate deficiency.
Cause of Adult Mumps. Adult mumps is caused by an infection with the mumps virus, which is found worldwide. The mumps virus is an RNA (ribonucleic acid) virus from the family Paramyxovirus of the genus Rubulavirus. The mumps virus only infects humans.
Before the vaccine, mumps was the most common cause of both meningitis (inflammation of the lining of the brain and spinal cord) and acquired deafness in the U.S. In men, mumps can infect the testicles, which can lead to infertility. Rubella is also known as German measles.