NDM Prevalence by Geographic Region
NDM-producing bacteria demonstrate highest prevalence in the Indian subcontinent, Middle East, and the Balkans, with worldwide distribution but relatively lower rates in the United States and other high-income countries. 1, 2
Global Distribution Patterns
High-Prevalence Regions
The Indian subcontinent shows the highest prevalence of NDM-producing bacteria globally, which is particularly significant given that NDM was first identified in New Delhi, India in 2007. 1, 2
The Middle East and Balkans represent additional high-prevalence regions where NDM-producing organisms are endemic. 2
These geographic patterns reflect both local epidemiology and the role of international travel and healthcare-associated transmission in spreading NDM globally. 1
Lower-Prevalence Regions
In the United States, NDM cases remain relatively rare but are increasing, with only 13 cases reported as of 2012, though this number has continued to rise. 1, 3
High-income countries generally have lower prevalence compared to endemic regions, though surveillance systems in these countries are more robust. 4
Important Epidemiologic Considerations
International travel and hospitalization in endemic regions (particularly the Indian subcontinent) are significant risk factors for acquiring NDM-producing bacteria. 1
Underdeveloped countries likely have significant underreporting due to limited surveillance systems and diagnostic capabilities, meaning the true global prevalence is likely higher than documented. 4
Pakistan demonstrated a 19.5% prevalence of NDM genes among carbapenem-resistant gram-negative bacilli in hospitalized patients at a tertiary care center, illustrating the substantial burden in South Asian healthcare settings. 5
Species and Strain Distribution
Klebsiella pneumoniae and Escherichia coli are the predominant bacterial carriers of NDM genes, with specific sequence types being most prevalent (K. pneumoniae: ST11, ST14, ST15, ST147; E. coli: ST167, ST410, ST617). 2
NDM variants have been identified in over 60 bacterial species across 11 bacterial families, demonstrating the widespread dissemination potential of these resistance determinants. 2
Clinical Implications of Geographic Variation
Knowledge of regional resistance patterns is essential for empirical treatment decisions, as emphasized by international guidelines for managing infections in areas with varying NDM prevalence. 4
Healthcare facilities should flag medical records of patients with history of NDM colonization or infection, particularly those with travel history to endemic regions. 1
The plasmid-mediated nature of NDM genes (commonly on IncX3, IncFII, or IncC replicon types) facilitates rapid horizontal transmission between bacterial species and geographic spread. 2