Obligate intracellular pathogens depend on their host for growth yet must also evade detection by host defenses. Here we investigate host adaptation in two Microsporidia, the specialist Edhazardia aedis and the generalist Vavraia culicis, pathogens of disease vector mosquitoes. Genomic analysis and deep RNA-Seq across infection time courses reveal fundamental differences between these pathogens...

SUMMARYVertically transmitted parasites may have positive, neutral or negative effects on host fitness, and are also predicted to exhibit sex-specific virulence to increase the proportion or fitness of the transmitting sex. We investigated these predictions in a study on the survival and sex ratio of offspring of the amphipod Gammarus roeseli from females infected by the vertically transmitted ...

To gain knowledge about laboratory testing practices for parasitic diseases, in 2000 we surveyed 562 laboratories in 9 US states, and 455 (81%) responded. Most laboratories (59%) indicated that they send specimens off site for parasite screening, and most laboratories (89%) did not routinely test fecal specimens for Cryptosporidium species, Cyclospora cayetanensis, or microsporidia, unless test...

A double-blind placebo-controlled trial was conducted to assess the efficacy and safety of albendazole (400 mg twice daily for 3 weeks) for the treatment of Encephalitozoon intestinalis infection in patients with AIDS. Clearance of microsporidia from the intestinal tract was obtained in 4 of 4 patients in the albendazole group versus 0 of 4 in the control group (P = .01, one-sided Fisher's exac...

The taxon Archezoa was proposed to unite a group of very odd eukaryotes that lack many of the characteristics classically associated with nucleated cells, in particular the mitochondrion. The hypothesis was that these cells diverged from other eukaryotes before these characters ever evolved, and therefore they represent ancient and primitive eukaryotic lineages. The kingdom comprised four group...

We have developed a new micromethod to study the effect of drugs on microsporidia, using MRC5 fibroblasts infected by 10(5) spores of Encephalitozoon cuniculi. After 3 days of incubation with various concentrations of drugs, parasitic foci were counted in stained cultures. The inhibition of microsporidial growth exceeding 90% with albendazole (0.005 microgram/ml), fumagillin (0.001 microgram/ml...

The aphelids are a small group of intracellular parasitoids of common species of eukaryotic phytoplankton with three known genera Aphelidium, Amoeboaphelidium, and Pseudaphelidium, and 10 valid species, which form along with related environmental sequences a very diversified group. The phyla Microsporidia and Cryptomycota, and the class Aphelidea have recently been considered to be a deep branc...

Feces from 62 beavers (Castor canadensis) in Massachusetts were examined by fluorescence microscopy (IFA) and polymerase chain reaction (PCR) for Microsporidia species, Cryptosporidium spp., and Giardia spp. between January 2002 and December 2004. PCR-positive specimens were further examined by gene sequencing. Protist parasites were detected in 6.4% of the beavers. All were subadults and kits....

Infection of Aedes aegypti (L.) (Diptera: Culicidae) with Edhazardia aedis (Microsporidia: Culicosporidae) reduced mean human host attraction and landing/probing rates in female mosquitoes by 53 and 62%, respectively, compared with rates in microsporidia-free females. Infection with E. aedis reduced the average weight of unfed female mosquitoes by 4%, caused them to imbibe 23% less blood, and t...