สถาบันวิจัยวิทยาศาสตร์สาธารณสุข

NATIONAL INSTITUTE OF HEALTH OF THAILAND

Laboratory confirmation of rabies-suspected cases by nested RT-PCR using saliva, urines and cerebrospinal fluids

Authors : Sirima Pattamadilok, Sanit Kumperasart, Patcha Incomserb, Karun Suthivarakom and Pathom Sawanpanyalert

 

Affiliations:        National Institute of health, Department of Medical Science, Ministry of PublicHealth, Nonthaburi 11000 Thailand
 
Source:            Presented at : The XIIth International Congress of Virology, 27 JUL-1 AUG 2002, Paris, France
 
Language:        English
 
Abstract:
 
According to the surveillance system by Division of Epidemiology, Ministry of Public Health of Thailand, there were approximately 66.8 deaths of rabies per year during 1995 and 1999. Most cases were diagnosed by history of exposure and clinical findings without any laboratory confirmation. These may lead to improper treatment for the patients and incorrect conclusion regarding the magnitude and severity of rabies problems in Thailand. To ensure that the neurologic disorders of the patients are really caused by rabies infection, a nested reverse transcription polymerase chain reaction (RT-PCR) method is developed and used to confirm or rule out rabies in human intravitam. Four primers were used for amplication of a fragment of N gene. Twenty-two clinical samples: 11 saliva, 8 urines and 3 cerebrospinal fluids (CSF), were taken from 12 patients suspected of having rabies, during 2000-2001. The results showed that 8 of them could be confirmed to have rabies genome and they died later. The other 2 patients from whom rabies viral RNA in saliva and urine could not be detected recovered and stayed alive. However, the other 2 patients from whom rabies virus nucleic acid could not be detected either did not survive. These results indicated that RT-PCR method could be used to reasonably ensure that the patients diagnosed by clinical signs and sysptoms were infected by rabies virus. However, further improvements are needed for effective laboratory confirmation methods.