In areas without malaria, Burkitts lymphoma is rare. Now it is appearing in AIDS patients. EB virus is also associated with nasopharyngeal carcinoma, in southeast Asia B. Infectious Mononucleosis - also caused by EB virus, evidently in developed countries children get infected early and develop Ab. Most serious complication is splenomegaly. Get lots of abnormal lymphocytes - mononuclear cells.
B cells produce several kinds of heterophile antibodies which can be tested for in screening assays.
C. Yellow fever - arbovirus, injected into skin by mosquito. Virus spread to lymph nodes, then liver, spleen, kidney and heart. Fever, chills, headache, backache - then nausea, vomiting and jaundice. Still endemic in Central America, Africa and South America. Monkeys are reservoir, Aedes mosquito is vector.