Sensitisation of Forest workers to the oligosaccharide galactose alpha-1, 3-galactose (alpha-gal) is strongly associated with tick bites but not with evidence of tick borne infections

The authors report on the results of IgE assays for galactose alpha-1, 3-galactose (alpha-gal) among forest workers in the region around Balyostock in North East Poland [1]. The patients were being seen for evaluation of possible tick-borne infections primarily tick-borne encephalitis and Lyme disease. The reason for carrying out assays for IgE to a -gal was because of recognition that in many areas of the world tick bites can induce sensitisation to this oligosaccharide which in turn is associated with an unusual form of delayed allergic reactions to red meat [2]. The results show a significant association between a history of tick bites and IgE to a -gal [3]. In addition, in keeping with previous studies they found no association between evidence of a tick borne infection and positive IgE to a -gal [1,4,5]. Our data on serological evidence of Rickettsial organisms among patients with AGS in two areas of the United States showed a high prevalence of positive sera among patients and controls [6]. The most likely explanation of that result is that the positive serology reflects ‘ infection ’ with Rickettsia amblyomii which is a common symbiont of the Lone Star tick but is not really a pathogen. What matters here is that none of the published results provide evidence that the pathogens carried by ticks con-tribute to a -gal sensitisation. There are several features of the report from Dr. Rutkowski and his colleagues that require comment. In particular, there is now evidence that subjects with sensitisation as judged by IgE ab, but no symptoms are at risk for two distinct clinical complications.