Testicular immunology
Mumps is a viral disease which causes swelling of the salivary glands and testes. The mumps virus lives in the upper respiratory tract and spreads through direct contact with saliva. Prior to widespread vaccination programs, it was a common childhood disease. Mumps is generally not serious in children, but in adults, where sperm have matured in the testis, it can cause more severe complications, such as infertility.
Tropical medicine
Tuberculosis (TB) is an infectious bacterial disease that can affect any part of the body, though it primarily affects the lungs. It is a disease that affects the poor and weak, and is far more common in developing countries. TB can either be in its latent or active form. TB can be latent for years, sometimes over a decade. Though TB research receives a mere 1/6th the funding of HIV research, the disease has killed more people in the last 200 years than any other infectious disease. According to the Liverpool School of Tropical Medicine, an estimated 9 million people were infected with TB in the year 2013 alone. That same year 1.5 million people died from TB. Of those 1.5 million, 360,000 were HIV positive. Tuberculosis is extremely expensive to treat, and treatments are now becoming ineffective due to drug-resistant TB strains. In the year 2016, 1.3 million people died from TB. An additional 374,000 people died who were co-infected with both TB and HIV. Research has shown that if the subject is infected with HIV, the risk of latent TB becoming active TB is between 12 and 20 times higher.