Many household dogs are carrying MRSA

Posted Jan 26, 2017 by Tim Sandle
Community transferred and acquired MRSA is a growing concern, especially for those admitted to hospital. One common reservoir for the antibiotic-resistant bacteria are domestic dogs. A new study reveals the extent of the problem.
A touching moment with a dog.
A touching moment with a dog.
Noël Zia Lee (CC BY 2.0)
Transfer of methicillin resistant Staphylococcus aureus (MRSA) in the community is an important matter of public health concern. Several studies have identified dogs kept by people as pets as carriers of MRSA. These studies have focused on the nose, which is an obvious site to monitor for the bacterium. However, according to one research group, the oral cavity should be screened as well. By ignoring this area, Texas State University researchers argue, the extent of MRSA carried by the dog population in the U.S. has been underestimated.
The reason why the mouth is important, the researchers state in an article for Infection Control Tips, is because many dogs will lick the face or skin of their owner (a common sign of a dog expressing affection).
To assess the impact, the researchers sampled 63 pet dogs by taking mouth swabs. Two dogs were found to be carrying MRSA, which means just over three percent of the sample population. In fact, results relating to the oral cavity of dogs produced results indicating a higher recovery rate of MRSA than from samples if the nares.
Applying statistics and extrapolating the findings, the data could signal up to one in 10 dogs as MRSA carriers. This will, nonetheless, depend on the geographical area. With geography, other studies have shown a 1 percent carrier rate in Ireland; a nine percent carrier rate in the U.K.; and zero carrier rate in Slovenia, in relation to dogs. Due to relatively small sample sizes, the studies will be somewhat limited.
MRSA is the bacterium responsible for difficult-to-treat infections in humans. The organism, through a combination of gene transfer and natural selection, has developed multi- resistance to common beta-lactam antibiotics. MRSA is a major health concern in hospitals, prisons, and nursing homes, especially for patients with open wounds, or who require the fitting of invasive devices. Those at greatest risk will have weakened immune systems. The main disease manifestations are infection (sepsis), toxic shock syndrome, and necrotizing pneumonia.
The researchers not only raise concerns about pets but also dogs used in hospitals. Several healthcare facilities use therapy dogs (these are dogs in healthcare facilities to meet and greet patients or residents). Such animals could pose a direct risk debilitated residents.