Mqurice, You might like this one:
Is the cat already out of the bag? Mainland China is now playing civet catch-up, but there are some indications that they may be late. Last season SARS CoVs were not only isolated from 6 civet cats, but also one raccoon dog. The sharing of a mutation C26523T between a masked palm civet isolate (SZ16) and the raccoon dog isolate (SZ13), suggests that the civet may have infected the raccoon dog.
The index case in Guangzhou for this season seems to trace back to another lineage with linkage to the masked palm civets and Beijing has ordered the slaughter of 10,000 civets. However, if the 99% homology in the N gene of the latest isolate means that there are 10-11 mutations in the 1068 nucleotides sequenced, then it seems likely that yet another animal has jumped into the line of transmission. The N gene is well conserved and most human isolates from last seasons had 100% identity with N gene in the masked palm civet isolate. None had anything like 10-11 mutations. If the current isolate really has that many mutations, then it seems likely that this case was infected by SARS CoV from another species, possibly coronavirus positive rats. Previously detected coronaviruses in rats (which were class II) had little homology with SARS CoVs. However, these rats could conceivably have a SARS CoV-like infection (a standard SARS CoV test would not detect the class II rat CoV, which is most closely related to murine hepatitis virus and more distantly related to human OC43 coronavirus which causes colds in humans). If the rats in the apartment were tested, it seems likely that the test would have been for SARS CoV and unlikely that such a test would detect a class II rat coronavirus.
Thus, the positive coronavirus test clearly raises the possibility that SARS CoV infected rats actually caused this infection and the rats may in fact have been oreviously infected with SARS CoVs from civets. In the Amoy Gardens outbreak, SARS CoV was found in 4 cats, 1 dog, and 4 rats and lab experiments have shown that cats and ferrets can transmit the SARS CoV to cage mates.
At this point more data is required on the rats in the apartment as well as others who have SARS-like conditions, now and in the past, because as has been shown in earlier tests on this Guangzhou index case, the mutated SARS CoV is not always detected by the current SARS CoV tests.
China Orders 10,000 Civet Cats Killed In Guangdong
DOW JONES NEWSWIRES
BEIJING (AP)--China Monday ordered some 10,000 civet cats in wildlife markets killed in its southern province of Guangdong after genetic tests suggested a link to a suspected SARS case.
All wildlife markets in Guangdong were ordered to close, Feng Liuxiang, deputy director of the province's health department, said on national television. Civets are served in wild game restaurants in Guangdong.
The announcement came after researchers at Hong Kong University said they found similarities between a virus found in the cats and in a suspected SARS patient in Guangdong, suggesting the disease might have jumped from animals.
"We will take resolute measures to close all the wildlife markets in Guangdong and to kill the civet cats," Feng said on the national noon newscast of China Central Television. |
