Recovery of a second instar Gasterophilus larva in a human infant: a case report.

We report a case in an infant of horse bot fly myiasis that was unusual because the maggot had developed to the second instar (of three potential instars). This represents the first report of such late development in a human. The case occurred in a rural area of the Pacific northwest (Washington) in late summer.

Reduction of tracheal mite parasitism of honey bees by swarming.

Based on population dynamics, tracheal mite (Acarapis woodi) parasitism of colonies of honey bees (Apis mellifera) appears to be, potentially at least, regulatory and stable. Empirical and theoretical considerations suggest, however, that intracolony population dynamics of mite-honey bee worker seem to be unstable in managed situations where honey bee worker population is allowed to grow unchecked. Experimental studies showed that tracheal mite population levels increased in a managed honey bee colony but were impaired in one in which brood rearing was interrupted by loss of the queen. Mite densities but not prevalence were lowered in experimental swarms kept from rearing brood. We propose that swarming reduces mite density within a colony, therefore implicating modern techniques of hive management in the sudden historical appearance of the mite on the Isle of Wight.

Honey bee mortality due to tracheal mite parasitism.

We demonstrate, by truncating the expected negative binomial distribution, that the tracheal mite parasite, Acarapis woodi, causes mortality in the European honey bee, Apis mellifera, but, that this mortality can be documented only during periods of low mite densities (mites per bee). At high mite densities, this technique no longer reveals mite-induced mortality. We suggest that this paradox results from a reduction in the mortality threshold at high mite densities, concealing mortality from our truncation procedures. Longitudinal comparisons of hive and forager bee cohorts, nevertheless, suggests mortality at all levels of infestation. We propose that persistent parasitism overcomes a colony's ability to compensate for losses, leading to its sudden decline and death.

Epidemiology of honey bee parasites.

The epidemiology of honey bee parasites has been somewhat neglected, but Lynn Royce and Philippe Rossignol describe their unique characteristics. Indeed, it appears that a parasite of social insects has in essence to adapt to two hosts: first, the individual worker within a colony, the numbers of which grow linearly and second, to the colony itself, the actual reproductive 'organism'. Transmission also has vertical and horizontal components. Analysis of tracheal mite populations in particular suggests that intracolony parasite levels are regulated by the swarming behavior of their hosts. Ironically, current and highly productive methods of honey bee management with movable hives curb swarming and may contribute to increasing the spread and the impact of some parasites. This insight may result in changing management practices to reduce the detrimental effects of bee parasites.