The Effect of Manuka Honey on MRSA

Studies of Manuka honey and its potential to down-regulate methicillin-resistant Staphylococcus aureus bacteria (MRSA), a gram-negative strain, have proven this honey’s ability to kill antibiotic-resistant bacteria.


Gram-negative bacteria are resistant to many drugs and have become increasingly resistant to most antibiotics. MRSA is spread frequently among patients in hospitals causing severe infections in wounds, surgical sites, infections in the blood as well as pneumonia.

The Good and the Bad About Antibiotics

From the time Penicillin was discovered in 1928 it has served us well. When antibiotics became pharmaceutical drugs in the US around 1940, infectious diseases could be stopped promptly. They worked so well that eventually prescriptions were given indiscriminately for viruses and other non-bacterial health issues. Antibiotics, however, are only effective in killing bacteria.

Antibiotics sweepingly kill good bacteria while in the process of destroying the bad. Therefore, random prescribing of antibiotics can lead to other diseases while afflicting the beneficial bacteria in the gut. The CDC has recognized this as a serious problem and provided guidelines to the medical profession to curb the use of antibiotics.

With Staphylococcus aureus’ built-in ability to find increasingly new ways to resist drugs and pass along the genetic material that allows other bacteria to become resistant, it became urgent to stop the opportunistic bacteria of the gram-negative strain. Medical researchers began looking at natural products to circumvent crafty microbial tendencies. Manuka honey was the substance of choice and study.

Manuka Honey

Bees collect this honey from the Manuka bush indigenous to New Zealand. The nectar of Manuka flowers contains a powerful chemical, Leptosperin, not found in any other flower or honey.

The microbial healing efficacy of Manuka honey is created from hydrogen peroxide, which when in contact with body fluids, is released through the enzyme glucose oxidase. Hydrogen peroxide is an effective antiseptic; however, contrary to other honeys, Manuka honey even heals without the release of hydrogen peroxide. This was tested with catalase, another enzyme, to remove the hydrogen peroxide. The special non-peroxide Manuka honey’s antibacterial activity is the UMF – Unique Manuka Factor. There are grades of UMF given in numbers. Any number greater than 10 is recommended as medicine for its antibacterial effects.

In addition to S. aureus, when tested, this UMF factor was found to be effective against a wide range of bacteria.

PubMed’s abstract is of a study by authors Jenkins RE and Cooper R, in the Journal of Antimicrobial Chemotherapy; Synergy between oxacillin and Manuka honey sensitizing methicillin-resistant Staphylococcus aureus to oxacillin.

This study showed that Manuka honey and oxacillin collaborated to inhibit MRSA. Interestingly, Manuka honey reversed MRSA’s resistance to the antibiotic by down-regulating mecR1, a cellular component responding to a variable, in this case the antibiotic, thus restoring susceptibility to antibiotics in MRSA.

Another abstract from Microbiology, by Maddocks SE, et al published by PubMed shows Manuka honey inhibits the development of Streptococcus pyogenes biofilms and causes reduced expression of fibronectin binding proteins.

S. pyogenes is a bacteria infiltrating wounds where it starts infections, destroys skin grafts and becomes a sticky polysaccharide covering the wound. Once the cover is formed, the bacteria is trapped and, when new bacteria are produced, it stays within the sticky cover. Biofilms are highly protective of bacteria under their cover and are as resistant to antibiotics applied to destroy S. pyogenes.

Manuka honey, known for its antimicrobial property, was used in this study as well. Manuka honey was first used in a test experiment with biofilm and plankton-type bacteria cultures, which resulted in bactericidal effects on both, but less so for the biofilm.

A higher concentration of Manuka honey, for a period of 24 hours, showed bacterial cell death in the biofilm layer as well as dissociation of cells from the biofilm. Less than destructive concentrations of Manuka honey prevented binding of Streptococcus pyogenes to human tissue protein fibronectin, responsible for cell adhesion, growth and critical in wound healing. It did not inhibit binding to fibrinogen, necessary in blood clotting.

Findings from this study indicate that Manuka honey has potential in the topical treatment of wounds infected with Streptococcus pyogenes.