Sequencing of common antibiotics may prevent drug resistant bacteria

Drug-resistant bacteria has become widespread. The World Health Organization (WHO) in 2014 made a plea for nations to monitor antibiotic resistance as there are serious public health consequences that can beginning to occur. A global survey showed alarmingly high rates of drug-resistant E-Coli and other bacteria that are capable of causing serious infections.

A recent study published by an international team based out of the University of Exeter in the UK has shown that alternating common antibiotics may prevent drug resistance. For many years, researchers have focused on using a combination of antibiotics as ‘cocktails’ with the thinking that a synergistic combination may be one answer to this growing problem.

In this recent study, the investigators used erythromycin and doxycycline to treat a test-tube model of resistant E-Coli. The antibiotics were given individually, in combination, and then in sequence. When given in certain sequences, they found that the infection was cleared. In most cases, the antibiotics given individually or combined failed to work. The researchers believe that specific doses of antibiotics combined with a specific sequence can make the bacteria sensitive and reduce risk of resistance.

As this was an experimental model, further research is needed to look at different combinations of drugs, doses and sequences.

Only two new classes of antibiotics have been introduced in the last 30 years. There is an urgent need to develop new drugs and while at the same time minimizing the prescribing and over utilization of antibiotics. Recently, the CDC announced that a drug-resistant form of the bacteria Shigella has caused illness in over 240 people since May 2014. 90% of the samples tested were resistant to the antibiotic Cipro. With more than 2 million cases of antibiotic resistant infections in the U.S. annually, rapid development of technologies to identify and characterize resistant bacteria has become a priority.

References:

Fuentes-Hernandez A., Plucain J., Gori F., et al. Using a sequential regimen to eliminate bacteria at sublethal antibiotic dosages. PLOS Biology. 2015 April 8;13 (4).

National Action Plan for Combating Antibiotic-Resistant Bacteria- https://www.whitehouse.gov/sites/default/files/docs/national_action_plan_for_combating_antibotic-resistant_bacteria.pdf