Effect of gentle stroking and vocalization on behaviour, mucosal immunity and upper respiratory disease in anxious shelter cats. 

Cats in shelters have health benefits from gentle stroking and quiet talk

Source: N. Gourkow, S.C. Hamon, C.J.C. Phillips 
Preventive Veterinary Medicine vol 117 November 2014 pp 266-275   

 A study of cats seen as anxious when they arrived at an animal shelter shows that ‘gentling’, or gently stroking and talking to them, can help calm them and bring other health benefits. The study involved  139 cats entering the British Columbia Society for the Prevention of Cruelty to Animals’ Vancouver branch. The cats were divided into two groups. One group was stroked and talked to for 10 minute sessions, four times a day over 10 days, while a control group was given no additional attention from humans. 

The research team rated the cats’ moods as either anxious or frustrated, or (negative), or content (positive), and found that gentled cats were less likely to show anxiety and frustration. The gentled cats also had higher levels of immunoglobins than the control cats, indicating that the gentled cats’ immune systems were working better, despite the stress of being in a shelter. Gentled cats were also less likely to test positive for infectious diseases such as cat flu (feline calcivirus and feline herpesvirus) and for bacterial infections  (Bordetella bronchiseptica  Mycoplasma felis, and Chlamydophila felis), while the control group showed an increase in cats testing positive over the ten day period.

This study shows that gently stroking and talking to cats can reduce their anxiety levels, and bring health benefits such as lower susceptibility to cat flu.