In America and Australia serious losses of adult bees have occurred for which no satisfactory cause could be assigned, the symptoms being similar to those described for Isle of Wight disease and Nosema-disease. Nosema apis is known to occur in these countries and may be partly responsible for this damage, though the presence of Nosema has not been demonstrated in all cases.
It is thus seen that there are a number of disorders in which the adult bees die in numbers, exhibiting a variety of symptoms. In some cases organisms are known to be associated with, and are perhaps the cause of, the disease. In others the cause can not be designated with certainty. None of these disorders is characterized by any outward symptom definitely diagnostic for that disease.
In all cases the stricken bees are unable to fly and die in numbers. It is possible, as suggested by several investigators, that inability of the bees to fly and various other conditions accompanying their death and cited as symptoms of different diseases, may represent merely the final stage in the weakening of the bees due to whatever cause.
These disorders, nearly all of obscure etiology, are characterized by a variety of symptoms and are known to the beekeeper under a wide variety of names. Besides those conditions supposedly due to old age, exposure, insufficient or improper food, or poisoning, may be mentioned dysentery, diarrhoea, Ruhr, May-sickness, May-pest, June-sickness, paralysis, palsy, trembling, dizziness, vertigo, spring dwindling, disappearing disease, dropsy, Sandlauferei, Fussgangerei, Isle of Wight disease, Nosema-disease, Aspergillusmycosis and "paratyphoid."
Source: The Normal and Pathological Histology of the Ventriculus of the Honey-Bee, with SpecialReference to Infection with Nosema apis. The Journal of Parasitology, Vol. 9, No. 3 (Mar., 1923), pp. 109-140
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Cold Ambient Temperature Promotes Nosema spp. Intensity in Honey Bees (Apis mellifera). Insects 8, no. 1 (2017): 20.
Abstract: Interactions between parasites and environmental factors have been implicated in the
loss of managed Western honey bee (=HB, Apis mellifera) colonies. Although laboratory data
suggest that cold temperature may limit the spread of Nosema ceranae, an invasive species and now
ubiquitous endoparasite of Western HBs, the impact of weather conditions on the distribution of this
microsporidian in the field is poorly understood.
Discussion
Molecular analyses confirmed previous studies [27,28], stating that N. ceranae is the predominant
Nosema species in Swiss honey bee colonies.
In this study, Nosema spp. intensities showed a trend to higher levels in winter and early spring;
this seasonal pattern was consistent for both years. These findings contradict previous reports stating
higher intensities in spring (e.g., [49]), but are in line with a recent study from Taiwan that found a peak
of honey bee worker midgut N. ceranae intensity in winter,
The study demonstrates that low ambient temperature can be advantageous for a parasite
population, assuming that higher spore loads enhance future transmission. It also highlights the
importance of studying such associations in the field, and not only under laboratory conditions.
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