[1] Amrita Inst Med Sci, Dept Gen Med, Kochi, Kerala, India
[2] Amrita Inst Med Sci, Div Infect Dis, Kochi, Kerala, India
[3] Amrita Inst Med Sci, Dept Infect Control & Epidemiol, Kochi, Kerala, India
[4] Amrita Inst Med Sci, Dept Microbiol, Kochi, Kerala, India
[5] Epsom & St Heliers NHS Trust, Dept Geriatr & Gen Med, Epsom, Surrey, England