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~New. ScientisL 24August. 1978 Major survey demonstrates virus link with human cancer Although a number of animall cancers are known to: be caused by viruses, the only instance of a human~ cancer virus that most expertscurrently, take seriouslyis. Epstein-Barr virus:. EBV, as it is known, belongs tothe.herpes virus family and is the cause of the reasonabl¢ commondisease., infectiouss mononuc leosis, which involves the non-mahgnant .protiferation of wbite blood celLS. But iq eertainparts of' Africa, the same virus is found inassodation with a.mallgnant white blood cell tumour-Burkitt's lym- phoma; Children with this tumour, whichisalmost.unheard of outsidee those regions of Afdca„have unusually large numbers of antib'odies againstEB V mtheir lilood- streams, and the virus's- DNA can actuallytle found in thetumour.e cells. Although this isstrong.evidence that the virus actually causes the tumour, it is only circumstantial and leavesoneim- portantquestion unansweredl almstt all African children are infected~., yet only about one in a 1000 develoosthe.tumoun Whatotherfactors.migtit be invol4ed? -Before biologists could make a serious starti on answering , thatt question, itt was ..essential to cronvihcethemselves that the associationn was causalandl not coind-dental-and! the way, to do that was byy a proper prospectiveepidemiologioal survey-a survey.in whicha verylargg number of' people are.screened for the snspeded; risk factorsliefores theyde-. • velop the disease. In Naturee this week (voFZ74, p 7S6)',Guy, de-The', of the Inter- natioual Agency for Research on Cancer in Lyan, with a team of associates„ re- ports the.resultsof a seven-year survey on42000 children under the.age of eight in thehigk-.risk arca of Uganda. In, fact, only 14 of thosee childrendevelope:d tumouTs--ratherfewer than the team expected.. But there were enough cases for the surveytoy establish that children who develop cancer do sao : after a Iong-standing. EBV infection and z that they have much larger numbers of, anti-EBV antibodies in their blood- d stteams thanmost'n other infected child- '0 ren, before.the.tumour develops..Or, as M.. A. Epstein, who was the co-discovererr of the virus inalymphomabiopsy in 1962 puts it,, a child with two times or more antibodies than are found in the.general population has 30 times the risk of developing the tumour-an association thatt is actually stronger than~ that between cigarette smokiagand lung ca!neer, nowacceptedw as one of tliee clearest casual relationships known in canoerresearch, But just ass all smokers do not develop lung cwncer,, all infected children do not develop Burkittslymphoma.. Thefirste obvious question to askiswhythe tumourr should be confined to certain geographical areas. And one of the best guesses so far is.that it may be because they are areas in which malaria is endemic. The idea that the virus and the malaria parasite maycollhborate iu,some way, toproduee the lymphoma has some.support inAheresults of laboratoryinvestigdtions on howtlie twoo organisms affect white blood cells... Bath, off them, it turnsouti cause the proli.feration, of one particular class ofl lymphocytes-the onee in which the viral DNA can be found ihlymphoma patients. Possibly the parasite, bypro- viding.more cells for the virus toenter, Cespite. 1Lee nwssiiesearch /or caus'alL viruses in human cancer, oniy Epstein-Barr virnuis.a strong candidate increasesthe.chance that one of those cells will be transformed byy the virus intoa.cancer cell (a transformation that'EBVis known to be ablee to effect in cultured cells). Butt thehnke withh mali,ria;., like the li¢kk with, the virus itselfi is far from absolute: aa very high proportion, of'African children have malaria and onlyy a very few off them develop Burkitt's lymphoma..TSatlinkmay become clearer as the resultt of a WHOcampaign~ to treat all.clnldren~in high-risk areas withantima.larial dt~ugs-if the linkk is real, thatshould result in.fewerlymphomas. And:nowthat it is firmly established, children at particularly high risk can beid'entified in ad4ance.by their anti-EBVantibodyV levels. It is therefore possible to think in terms of'developingf a vac- cine for the.vulnerable group. O