Gram-negative bacteria: prevention, surveillance and epidemiology

The characteristics, management and surveillance of Gram-negative bacteria such as Escherichia coli, Klebsiella and Pseudomonas aeruginosa.

There are many different types of Gram-negative bacteria. Some live in the intestine harmlessly, while others may cause a variety of diseases.

Bacteria that are normally harmless in their normal environment can cause problems if they grow in other parts of the body and can cause a range of infections with differing severity and associated mortality. One of the most serious infections Gram-negatives can cause bloodstream infections.

Gram-negative bacteria such as Escherichia coli, Klebsiella spp. and Pseudomonas aeruginosa are the leading causes of healthcare associated bloodstream infections.

Gram-negative bacteria can be resistant to antibiotics and in some cases will be multi-resistant rendering most available antibiotics useless. Some of the antibiotic resistance mechanisms are on mobile genetic elements, such as plasmids, which allow the genes that encode resistance to spread more easily, and importantly, between different bacterial species.

Diagnosis, prevention and management

Guidance on preventing healthcare associated Gram-negative bacterial bloodstream infections is available from the NHS Improvement website.

Read NHS Improvement’s ambition to halve healthcare associated Gram-negative bloodstream infections

Submit data

Use the enhanced surveillance form to report mandatory surveillance of Gram-negative bacteria.


In November 2016, the government announced plans to reduce infections across the NHS. This includes plans to reduce the number of healthcare associated Gram-negative bloodstream infections by 50%, by financial year 2020 to 2021. In response to this, PHE expanded their collection of Gram-negative blood stream infections from E. coli bacteraemia (mandated to be reported in June 2011) to include Pseudomonas aeruginosa and Klebsiella spp.

Some of our mandatory surveillance publications will also change from October 2017. See Gram-negative bacteraemia infections updates on the HCAI Data Capture System (DCS) Help and Support page for details.

Official statistics compliance

PHE produces official statistics on healthcare associated infections (HCAI) mandatory surveillance in accordance with the code of practice, and they are designated as national statistics.

User engagement

The stakeholder engagement summary collates evidence from mandatory HCAI surveillance statistics users and provides:

  • a summary of how the statistics are used
  • views on how provision of the statistics meets the needs of users
  • our actions in response to user feedback

PHE updates these document as user feedback is received.

Read minutes of the HCAI mandatory surveillance stakeholder engagement forum.

Published 1 August 2017