HFRS has been diagnosed accurately in this area, so we haven't known infected patients for longer follow-up. Nonetheless, there is a striking similarity in the results from several different medical centers, which suggests that chronic renal insufficiency is not an uncommon sequela among patients sick enough to be hospitalized during acute illness. We are continuing to examine these patients over time, and we are trying to determine if there is a correlation between seropositivity and chronic renal disease or hypertension among long-term residents of the area as seen in Baltimore.
To summarize, the past decade has yielded a wealth of new knowledge regarding hemorrhagic fever with renal syndrome. We now know that several different viruses are capable of causing clinically similar diseases, which are called collectively hemorrhagic fever with renal syndrome. These viruses are maintained in nature by chronically infected rodents, and they are distributed much more widely than once suspected. We are in a position to diagnose acute HFRS rapidly and accurately, and we have preliminary evidence to suggest that past hantaviral infection may be associated with subsequent development of chronic renal disease.
Providing the proof of this association represents an exceptional challenge, and the resources of the Follow-up Agency, the Department of Defense, and the Veterans Administration are especially well suited to answer this question definitively. Hantaviral infections can be acquired either overseas, including as part of military service, or right here in the United States, from local infected rats; but regardless of the source of infection, there is growing evidence that some patients will progress to chronic renal disease and perhaps end-stage kidney failure. It has been estimated that the United States spends more than $30 billion a year for medical care for kidney and urologic diseases, and about $3 billion is Medicare payments for dialysis and transplantation for people with end-stage kidney disease. If even a small portion of this burden is due to hantaviral infections, say, the 2% we found in our Baltimore dialysis units, then we, as a nation, are spending about $60 million a year on this disease. Clearly, we cannot afford to let this question remain unresolved.
1. Schmaljohn, C.S. Hasty, S.E. Dalrymple, J.M. LeDuc, J.W. Lee, H.W. von Bonsdorff, C.H. Brummer-Korvenkontio, M. Vaheri, A. Tsai, T.F. Regnery, H.L. Goldgaber, D. Lee, P.W. 1985 Antigenic and genetic properties of viruses linked to hemorrhagic fever with renal syndrome Science 227 : 1041-1044
2. Earle, D.P. 1954 Symposium on epidemic hemorrhagic fever Am. J. Med. 16 : 617-709
3. Lee, H.W. Lee, P.W. Johnson, K.M. 1978 Isolation of the etiologic agent of Korean hemorrhagic fever J. Infect. Dis. 137 : 298-308