The World Health Organisation (WHO) estimates that hundreds of millions of patients around the world are affected by healthcare-associated infection (HAI).
HAI, it said on its website, results in "prolonged hospital stays, long-term disability, increased resistance of micro-organisms to antimicrobials, massive additional costs for health systems, high costs for patients and their family, and unnecessary deaths".
But the true global burden "remains unknown because of the difficulty in gathering reliable data".
The WHO said most countries lack surveillance systems for HAI. The lack of uniform criteria for HAI makes comparisons difficult too.
It estimates that one in 10 patients worldwide would catch a bug while in hospital.
A spokesman for the Ministry of Health said only a few countries have attempted national studies such as the one Singapore conducted.
But since methodology and patient population would be different, it does not make sense to compare Singapore's results with theirs, the spokesman said.
She added: "The intent of the study is to determine the local baseline prevalence of healthcare-associated infections and antimicrobial use in Singapore acute-care hospitals, as well as to identify priority areas for intervention.
"The findings of the study are meant to help hospitals prioritise interventions and the subsequent study will provide a better understanding of the causes and cost of healthcare-associated infections and antimicrobial use in Singapore."