In an undiagnosed case of hemorrhagic disease in China, Marjorie Pollack, a ProMED editor, used GIDEON to help figure out the differential diagnosis. From the ProMED note:
Using the database of the Global Infectious Disease and Epidemiology Network (GIDEON ) to see possible etiologies for a hemorrhagic fever syndrome in China, the most likely diagnosis would be Old World hantavirus infection (57 percent probability), followed by _Streptococcus suis_ infection (40 percent), leptospirosis (1.8 percent) and Crimean-Congo hemorrhagic fever (CCHF — less than one percent probability).
According to the GIDEON database, hantaviruses are endemic in 28 of the 32 provinces, with most cases occurring in the eastern and northeastern provinces (where Shandong is located). Hantaan virus is endemic to Hubei, Heilongjiang, Jiangxi, Jilin and Shanxi. (Fang LQ, Li CY, Yang H, Wu XM, Yang H, Chen HX, Li XW, Cao WC [Using geographic information system to study the association between epidemic areas and main animal hosts of hemorrhagic fever with renal syndrome in China.] Zhonghua Liu Xing Bing Xue Za Zhi 2004 Nov ;25(11):929-33.
– 52.2 percent of infections in Hubei are caused by Hantaan virus, and 31.5 percent by Seoul virus.
– Most infections in Shandong province are caused by Seoul virus. (Wang ZQ, Wang YL, Fu JH, Zhao L, Sun CY, Zhang XQ, Zhang YX, Fan SZ, Wang ND [Molecular analysis of hantavirus isolated from Shandong province]. Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi 2003 Jun ;17(2):121-3.)
– Seoul virus was identified in humans and rodents (_Rattus norvegicus_ and _Mus musculus_) in Beijing during 2003 to 2005. (Zuo SQ, Zhang PH, Jiang JF, Zhan L, Wu XM, Zhao WJ, Wang RM, Tang F, Dun Z, Cao WC. Seoul virus in patients and rodents from Beijing, China. Am J Trop Med Hyg 2008 May ;78(5):833-7.
A new Puumala virus subtype, most closely related to strains from Japan and South Korea, has been isolated from bank voles in Northeast China. (2007 publication) (Tang LH, Zhang QF, Xiu MH, Gu GW, Bo S, Yang XD, Liang MF, Li DX [Identification of a new Puumala hantavirus subtype in rodents from China] Bing Du Xue Bao 2007 Jul ;23(4):320-5. The abstract does not give any information about human infection by it.
ProMED-mail has reported on hantavirus outbreaks in China earlier this year in Inner Mongolia (see Hantavirus infection – Taiwan ex China (Inner Mongolia) 20080119.0249), and in prior years (see references below)
According to the GIDEON database, CCHF has been reported from the southwestern desert region in Xinjiang province and is referred to as Xinjiang fever. Hence it would be a significant geographic change were this outbreak to be due to CCHF. There is also mention that 10 to 20 percent of sheep, goats and cattle in Sichuan are seropositive — so movement of livestock from the southwest to other provinces may very well move the disease geographically.
One should not forget the earlier major outbreaks of _Streptococcus suis_ in China in 2005. A recurrence of the problem is possible.
It is noteworthy that according to the question and answer part of the referred media report, there is mention that the cases to date have been in predominantly in men, suggesting that exposure may well be occupational, which places both hantavirus infection and _Streptococcus suis_ as leading possibilities for the etiologic agent for this outbreak. The outbreak is occurring in a rural zone where there is a high likelihood of exposure of males to rodents and to the porcine population during usual occupational activities in an agricultural zone.