No evidence for sylvatic cycles of chikungunya, dengue and Zika viruses in African green monkeys (Chlorocebus aethiops sabaeus) on St. Kitts, West Indies.

BACKGROUND: Dengue, chikungunya and Zika viruses (DENV, CHIKV and ZIKV) are transmitted in sylvatic transmission cycles between non-human primates and forest (sylvan) mosquitoes in Africa and Asia. It remains unclear if sylvatic cycles exist or could establish themselves elsewhere and contribute to the epidemiology of these diseases. The Caribbean island of St. Kitts has a large African green monkey (AGM) (Chlorocebus aethiops sabaeus) population and is therefore ideally suited to investigate sylvatic cycles. METHODS: We tested 858 AGM sera by ELISA and PRNT for virus-specific antibodies and collected and identified 9704 potential arbovirus vector mosquitoes. Mosquitoes were homogenized in 513 pools for testing by viral isolation in cell culture and by multiplex RT-qPCR after RNA extraction to detect the presence of DENV, CHIKV and ZIKVs. DNA was extracted from 122 visibly blood-fed individual mosquitoes and a polymorphic region of the hydroxymethylbilane synthase gene (HMBS) was amplified by PCR to determine if mosquitoes had fed on AGMs or humans. RESULTS: All of the AGMs were negative for DENV, CHIKV or ZIKV antibodies. However, one AGM did have evidence of an undifferentiated Flavivirus infection. Similarly, DENV, CHIKV and ZIKV were not detected in any of the mosquito pools by PCR or culture. AGMs were not the source of any of the mosquito blood meals. CONCLUSION: Sylvatic cycles involving AGMs and DENV, CHIKV and ZIKV do not currently exist on St. Kitts.

Whole genome analysis provides evidence for porcine-to-simian interspecies transmission of rotavirus-A.

We report here whole genome analysis of a porcine rotavirus-A (RVA) strain RVA/Pig-wt/KNA/ET8B/2015/G5P[13] detected in a diarrheic piglet, and nearly whole genome (except for VP4 gene) analysis of a simian RVA strain RVA/Simian-wt/KNA/08979/2015/G5P[X] detected in a non-diarrheic African green monkey (AGM) on the island of St. Kitts, Caribbean region. Strain ET8B exhibited a G5-P[13]-I5-R1-C1-M1-A8-N1-T7-E1-H1 genotype constellation that was identical to those of Brazilian porcine RVA G5P[13] strains RVA/Pig-wt/BRA/ROTA01/2013/G5P[13] and RVA/Pig-wt/BRA/ROTA07/2013/G5P[13], the only porcine G5P[13] RVAs that have been analyzed for the whole genome so far. Phylogenetically, all the 11 gene segments of ET8B were closely related to those of porcine and porcine-like human RVAs within the respective genotypes. Although the porcine G5P[13] RVAs exhibited identical genotype constellations, ET8B did not appear to share common evolutionary pathways with the Brazilian porcine G5P[13] RVAs. Interestingly, the VP2, VP3, VP6, VP7, and NSP1-NSP5 genes of simian RVA strain 08979 were closely related to those of porcine and porcine-like human RVA strains, exhibiting 99%-100% nucleotide sequence identities to cognate genes of co-circulating porcine RVA strain ET8B. On the other hand, the VP1 of 08979 appeared to be genetically divergent from porcine and human RVAs within the R1 genotype, and its exact origin could not be ascertained. Taken together, these observations suggested that simian strain 08979 might have been derived from interspecies transmission events involving transmission of ET8B-like RVAs from pigs to AGMs. In St. Kitts, AGMs often stray from the wild into livestock farms. Therefore, it may be possible that the AGM acquired the infection from a pig farm on the island. To our knowledge, this is the first report on detection of porcine-like RVAs in monkeys. Also, the present study is the first to report whole genomic analysis of a porcine RVA strain from the Caribbean region.

Nocardia cyriacigeorgica as the causative agent of mandibular osteomyelitis (lumpy jaw) in a cat.

An unusual case of osteomyelitis caused by Nocardia cyriacigeorgica infection and resulting in mandibular osteomyelitis and cellulitis (lumpy jaw) is described in a young cat. A 1-cm hard nodular mass was an incidental finding in the right mandible of a 14-month-old cat during routine physical examination. The lesion was fast growing, reaching up to 6 cm in its largest dimension over a 5-week period. A core biopsy of the affected mandible revealed foci of osteolysis, woven bone formation, and a few large clusters of filamentous bacteria surrounded by fine eosinophilic amorphous material bordered by neutrophils, plasma cells, macrophages, and occasional multinucleated giant cells. Pure cultures of acid-fast variable, Gram-positive filamentous bacteria were recovered on blood and chocolate agar plates at 48-hr postinoculation. On amplification and sequencing of the 16S ribosomal RNA and 65-kDa heat shock protein genes, the microorganisms were identified as N. cyriacigeorgica, within the actinomycetes.