[1] Univ Malaya, Dept Med Microbiol, Fac Med, Kuala Lumpur 50603, Malaysia
[2] Int Med Univ, Dept Life Sci, Sch Pharm, 126,Jalan Jalil Perkasa 19, Kuala Lumpur 57000, Malaysia
[3] Univ Malaya, Dept Med Microbiol, Fac Med, Kuala Lumpur 50603, Malaysia