Virus/antibiotic combo recruited to kill resistant bacteria

Sometimes, viruses can help us. According to a new study, a combination of antibiotics and a bacteria-killing virus eradicates harmful bacteria better than either one is capable of doing on its own. The research was carried out by scientists from the Université de Montpellier in France, and the University of Pittsburgh in the US.

For the study, the team set out to develop an alternative treatment for infections caused by an antibiotic-resistant bacteria known as Mycobacterium abscessus. It can cause severe damage to human lungs – especially in people with cystic fibrosis – and is related to the bacteria that cause leprosy and tuberculosis.

The scientists conducted their experiments on zebrafish that had been genetically engineered to both carry the genetic mutation which causes cystic fibrosis, and to mimic how the human immune system responds to bacterial infections. Twelve days after those fish had been exposed to M. abscessus bacteria, they developed serious infections with abscesses, and only 20 percent of them ultimately survived.

Next, a new batch of fish were injected with a bacteriophage (a bacteria-killing virus) nicknamed "Muddy." When those fish were exposed to M. abscessus, they had fewer of the abscesses, and a 40-percent survival rate. Another group of fish, that weren't treated with Muddy but that were treated with the antibiotic rifabutin, had the same rate of survival.

However, when yet another batch of fish were treated with both Muddy and rifabutin, they had far fewer abscesses than any of the other groups, and 70 percent of them survived. It is now hoped that after further experiments are conducted, the treatment could be extended to humans in clinical trials.