This paper covers the epidemics of diabetes occurring due to immune stimulation (via vaccines) across different populations. A nice remark made at the end about obesity being seen in horses that have been vaccinated.

Classen, J.B. Evidence childhood epidemics of type 1 and type 2 diabetes are opposite extremes of an immune spectrum disorder induced by immune stimulants. Role of race and associated cortisol activity as a major determining factor of the type of diabetes. Diab Met Syndr: Clin Res Rev (2008), doi:10.1016/j.dsx.2008.10.010

Some quotes from this paper (you can download it below), first the abstract:

Design: Prior publications have provided evidence that type 1 and type 2 diabetes are opposite extremes of an immune spectrum disorder. Method: The risk of type 1 diabetes was correlated with the risk of type 2 diabetes in different races. Results: Races with high risk of developing type 2 diabetes have an decreased risk of developing type 1 diabetes (correlation coefficients -0.5 or -0.85 depending on age, p < 0.05). Maori, American Indians, Asians, Australian Aboriginals and US Black children have a higher risk of developing type 2 diabetes but a low risk of type 1 diabetes compared to White children. Conclusion: Population data is consistent with type 1 and type 2 diabetes being opposite ends of an immune spectrum disorder.

Also:

There are simultaneous epidemics of type 1 and type 2 diabetes/metabolic syndrome in children and a single cause is likely. Evidence has been presented that that type 1 diabetes and type 2 diabetes/metabolic syndrome are opposite extremes of an immune mediated disorder induced by a rise in iatrogenic immune stimulation [1,2]. The current data further supports previously published evidence that type 1 and type 2 diabetes are opposite ends of a immune spectrum disorder.

And also (and look at the remark in the last sentence):

The most productive way of stopping the simultaneous epidemics of type 1 diabetes and type 2 diabetes/metabolic syndrome is to prevent exposure to unnecessary immunological challenges. Previous papers have provided evidence that a single agent, BCG immunization, was associated with an increased risk of type 1 diabetes (an autoimmune disease) or type 2 diabetes depending on race [1]. BCG vaccination of school age Europeans was associated with an increased risk of developing type 1 diabetes while immunization of school age Japanese children was associated with an increased risk of type 2 diabetes. The discontinuation of BCG immunization in Japan was followed by a rapid decrease in type 2 diabetes. Similar declines in the incidence of type 1 diabetes in Denmark occurred following the discontinuation of the BCG vaccine [14]. Such steps will likely be fruitful in pets as well. Recently an epidemic of obesity has been recorded in primarily grass fed horses [15], creatures that are heavily immunized and where the etiology of the epidemic cannot be confused by the presence of fast food, sodas, television and video games.

Download the paper in PDF here.