Gram-negative bacteria

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Recently, a multi-centre survey carried out by the ICMR to spot the trend in antibiotic resistance across the country showed Acinetobacter baumannii, a gram-negative bacteria known to cause infection in the blood, urinary tract and lungs among others, was resistant to high-end antibiotics.
- Antimicrobial Resistance: It occurs when bacteria, viruses, fungi and parasites change over time and no longer respond to medicines, making infections harder to treat and increasing the risk of disease spread.
The survey found 5% samples of Acinetobacter baumannii tested in 2021 were resistant to carbapenems, a high-end antibiotic.

Gram-negative bacteria are classified by the color they turn after a chemical process called Gram staining is used on them.
- Gram-negative bacteria stain red when this process is used.
- Gram-positive bacteria stain blue.
Gram-negative bacteria are enclosed in a protective capsule. This capsule helps prevent white blood cells (which fight infection) from ingesting the bacteria. Under the capsule, gram-negative bacteria have an outer membrane that protects them against certain antibiotics, such as penicillin.
When disrupted, this membrane releases toxic substances called endotoxins. Endotoxins contribute to the severity of symptoms during infections with gram-negative bacteria.
Gram-negative bacteria cause infections including pneumonia, bloodstream infections, wound or surgical site infections, and meningitis in healthcare settings.