Though the virus has not yet been identified, several causes - including SARS, as many in the country feared - have been ruled out.
ເຖິງແມ່ນວ່າເຊື້ອໄວຣັດນີ້ຍັງບໍ່ທັນໄດ້ຖືກລະບຸຕົວ, ສາເຫດຫຼາຍຢ່າງ - ລວມທັງໂຣກ SARS, ໃນຂະນະທີ່ຫຼາຍປະເທດຢ້ານກົວ - ໄດ້ຖືກປະຕິເສດ.