14 DAY TRIAL // A new study by researchers in the United States suggests that more than 40 percent of people who were bitten by cats go on to develop some form of depression later on. The main reason for this, the study suggests, is infections with a microbe that lives in the guts of pet cats.
People infected with this microbe, known as Toxoplasma gondii (T gondii), are more likely to commit suicide following bouts of depression than people who are not infected, statistics show. The new study was led by researchers at the University of Michigan, the Daily Mail reports.
One of the main implications of the investigation is that cat owners who have been bitten by their pets should be screened for depression at some point. According to the data presented in the new study, bitten cat owners were 500 percent more likely to develop depression than other people.
To arrive at this conclusion, U-M scientists surveyed the cases of around one million people. Four in ten bite victims went on to develop at least some of the symptoms associated with depression. In men, the risk was quantified at 24.2 percent, while 47 percent of women showed signs of the disorder.
This difference could suggest that men may benefit from a protection mechanism that is non-existent, or less efficient, in women. Within the average population, the team adds, the depression rate levels off somewhere around 8.8 percent, so there is definitely a causal link between cat bites and this condition.
A similar effect was recorded when it came to dog bits as well, except that the values were a lot smaller, around 28.7 percent. Scientists with the group are quick to point out that the results of their research do not necessarily imply that cat bites cause depression.
“It may seem counter-intuitive to consider screening in someone who seeks treatment for an acute injury from a household pet, but our findings suggest that it could be beneficial. Although we found an association between bites and depression, our work does not show that cat bites cause depression,” says the leader of the study, U-M investigator Dr. David Hanauer.
Other scientists, including King's College London biological psychiatry professor Dr. Carmine Pariante, agree that more work is needed to certify this link. “Essentially, they found that people who had cats were more likely to have depression. One explanation, for example, might be that people who are lonely are more likely to have a pet, and be more prone to depression,” the expert concludes.