AMR Dipstick Test

Why in news ?

• Scientists at THSTI Faridabad developed a low-cost dipstick assay to detect antimicrobial resistance (AMR) genes in sewage, enabling rapid population-level surveillance in a major public health threat area.
• Study published in Nature Communications (Dec 2025) validated the test across 381 sewage sites in six Indian States, confirming sewage as a major AMR reservoir and transmission pathway.
• The assay costs only ₹400–550 per test, versus ₹9,000+ for shotgun sequencing, making large-scale AMR monitoring feasible for resource-constrained public health systems.

Basics and background

• Antimicrobial resistance (AMR) occurs when microbes evolve mechanisms to survive drugs, making infections harder to treat and increasing morbidity, mortality, and healthcare costs globally.
• AMR is driven by antibiotic misuse in humans, livestock, and agriculture, plus pharmaceutical effluents and poor wastewater treatment infrastructure, especially in densely populated developing countries.
• Sewage surveillance captures community-level signals from households, hospitals, farms, and industries, offering early-warning insights into antibiotic use and resistance trends.

Scientific and technological dimension

• The dipstick works like a rapid diagnostic test, detecting amplified resistance genes from sewage DNA using PCR-based amplification and visible colour-band readouts.
• Each dipstick detects 16 resistance genes and provides results within two hours, enabling time-efficient, field-friendly surveillance without advanced laboratory infrastructure.
• The platform is upgradeable within three days if new resistance genes emerge globally, ensuring adaptability to evolving microbial threats.

Public health and governance dimension

• India is recognised as a global AMR hotspot by WHO, with high infectious disease burden and widespread antibiotic access without prescriptions.
• AMR threatens procedures like surgeries, chemotherapy, and organ transplants, where effective antibiotics are critical for infection prevention.
• Low-cost surveillance supports India’s National Action Plan on AMR (NAP-AMR) goals on monitoring and containment.

Economic dimension

• AMR could cause 10 million deaths annually by 2050 globally and reduce global GDP by 2–3.5%, according to international estimates.
• Affordable surveillance reduces long-term healthcare costs by enabling targeted interventions and rational antibiotic stewardship.
• Low-cost diagnostics are vital for LMICs, where high-end genomic surveillance is financially unsustainable.

Social and ethical dimension

• Sewage surveillance is considered ethically acceptable since it monitors communities anonymously without targeting individuals, avoiding privacy and consent concerns.
• Helps protect vulnerable populations who suffer disproportionately from drug-resistant infections due to limited healthcare access.
• Encourages a One Health approach, integrating human, animal, and environmental health.

Data and evidence

• Researchers analysed sewage from 381 locations across Assam, Haryana, Jharkhand, UP, Uttarakhand, and West Bengal, confirming widespread antibiotic residues and resistance genes.
• India has some of the highest antibiotic consumption rates globally, increasing selection pressure for resistant microbes.
• Only a fraction of wastewater in India undergoes effective treatment, facilitating AMR spread.

Limitations and cautions

• Detection of a gene signals possibility of resistance, not presence of a live pathogenic organism; genes alone do not cause disease.
• AMR expression varies by gene combinations and ecological context, requiring cautious interpretation.
• Dipsticks complement but do not replace culture-based and genomic surveillance.

Way forward

• Integrate dipstick surveillance into routine urban wastewater monitoring under public health and Jal Shakti frameworks.
• Link results to antibiotic stewardship programmes and regulation of pharmaceutical effluents.
• Expand AMR labs and genomic surveillance for confirmatory analysis.
• Strengthen wastewater treatment infrastructure under AMR containment strategy.
• Promote global data sharing aligned with WHO Global AMR Surveillance System (GLASS).

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