Obesity as an Infection

A new study sheds light on the possibility that obesity can be infectious. Yes, 'infectious' as in contagious. Before you laugh, read this:

Physiologist Leah Whigham of the University of Wisconsin-Madison and her colleagues inoculated young male chickens with three strains of adenovirus --- Ad-2, Ad-31 and Ad-37. She and her team then monitored the chickens for three and a half weeks, recording their food intake throughout. Though the infected chickens and noninfected controls consumed the same amount of food and were exposed to the same conditions, chickens carrying Ad-37 were found to have nearly three times as much fat in their guts and more than two times as much fat over their entire body at the end of the three-and-a-half week period. The other two virus strains appeared to have little effect on weight.

[Scientific American , 30 Jan 2006]

I got several questions. If it were true, what is the incubation period? Can the transmission happen from human to human? If I wash my hands and cover my mouth and nose when somebody obese is sneezing, can I avoid getting obese myself?

The virus concerned, Ad-37, is an adenovirus. It comes from the family of viruses known to transmit pharyngitis, pneumonia, most upper respiratory tract infections, and some eye problems. Transmission, as you know by now, is usually by inhalation of infected respiratory droplets.

Physiologist Leah Whigham pointed out that "Ad-37 is the third human adenovirus to increase adiposity in animals, but not all adenoviruses produce obesity." This is an interesting study and a good yet frightening theory if it were true.

I know it sounds amusing, but hey, look what happened to these guys. They were also laughed at when they first told the world that ulcer was caused by an infection. Definitely, more studies are needed to see if there is also human-to-human transmission of this 'obesity-infection' caused by Ad-37.