Wild, Laboratory, and Pet Rats-Induced Seoul Hantavirus Disease Worldwide

Rat-borne Seoul hantaviruses are only just being recognized globally as important human pathogens, even though they have been studied and isolated on 4 different continents (Asia, Europe, the Americas, and Africa) since the early 1980s. Recent reports from Europe and the USA described Seoul hantavirus infection in pet rats and their breeders or owners, suggesting the potential emergence of a “new” public health problem. Wild and laboratory rat-induced Seoul hantavirus infections have, however, been described since the early eighties, due to the omnipresence of the rodent reservoir, the brown rat Rattus norvegicus. Recent studies showed no fundamental differences between pathogenicity and phylogeny of pet rat-Seoul hantaviruses and their formerly described wild or laboratory rat counterparts. The paucity of diagnosed Seoul virus-induced disease in the West is in striking contrast to the thousands of cases recorded since the 1980s in the Far-East, particularly in China. This review of four continents (Asia, Europe, America, and Africa) puts this “emerging infection” in historic perspective, concluding there is an urgent need for greater medical awareness of Seoul virus-induced human pathology in many parts of the world. Given the mostly milder and atypical clinical presentation, sometimes with preserved normal kidney function, the importance of simple urine examination is stressed, since initial, massive but transient proteinuria and microhematuria are rarely lacking. With increasingly sophisticated technology and enhanced clinical awareness, many specific hantaviruses are now recognized; however, SEOV remains the globally most widely distributed hantavirus.