Pets under microscope in bug study

About half of New Zealand households have at least two cats and a third have dogs.

Scientists looking for link between animals and spread of drug-resistant bacteria.

Scientists investigating the rising spread of drug-resistant bugs in our homes have thrown up a hairy potential culprit: our pet pooches and moggies.

In what's thought to be a world first, a team of researchers will survey dozens of Auckland households to seek out any link between ownership of cats and dogs and the spread of certain bacterium that can hold out against antibiotics.

Antibiotic resistance in bacteria is increasingly becoming a global threat to human health and in New Zealand there has been a recent rise in cases involving two particular types: E. coli and Klebsiella.

"Strains of the resistant bugs are spread through communities," said Massey University epidemiologist Dr Jackie Benschop, who is leading the collaborative project.

"We want to understand the dynamics of a small community, a family, to ultimately inform public interventions to reduce transmission."

What hasn't been clear is what is driving bacteria movement around households.

The fact that both E. coli and Klebsiella. are also found in our cats and dogs, as well as wild birds, has led scientists to look at animals as possible carriers.

Dr Benschop noted New Zealand has a high rate of pet ownership: about half of Kiwi households have at least two cats and a third have dogs.

One of our key messages is that the benefits of pet ownership, in terms of social and physical health, far outweigh the risks.

Dr Jackie Benschop

"So, for the first time, we are exploring the idea that pets could be a risk factor for people having these infections."

Over the space of a year, the team aim to survey around 175 homes in the Auckland region where there have been cases of infections, and compare them against a control group totalling 525 homes.

Along with distributing questionnaires, Dr Benschop's fellow researchers Zoe Grange and Leah Toombs-Ruane will use DNA sequencing of bacteria from human and animal faeces to better understand how spread is occurring between members of the household.

But Dr Benschop said there was every chance scientists might be barking up the wrong tree by pointing to cats and dogs.

"And even if we don't find bacterium moves much between pets and humans, that would be a finding in itself.

Further, she stressed the research shouldn't scare pet owners.

"One of our key messages is that the benefits of pet ownership, in terms of social and physical health, far outweigh the risks," Dr Benschop said.

Antiseptics may strengthen bacteria

Two Otago University micro-biologists have begun investigating whether an everyday compound used in antiseptics could be helping bacteria become more resistant to antibiotics.

In a new study, Dr Deborah Williamson and Professor Gregory Cook are focusing on a nasty bacterium called Staphylococcus aureus, which has a higher rate of infections in New Zealand than elsewhere in the developed world.

To treat skin infections and stop its spread, sufferers typically use antibiotic topical creams and wash their hands with antiseptics containing the synthetic compound chlorhexidine, or CHX. However, there has been concern about the potential increase in resistance to both antibiotics and antiseptics.

The scientists' Marsden Fund-supported research will investigate the role of CHX in promoting the development of antibiotic resistance, particularly in the context of Staphylococcus aureus.

Ultimately, their work could inform debate around the widespread use of antiseptics and find strategies to limit the spread of resistant Staphylococcus aureus.