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

Parasit Vectors. 2020 Oct 30;13(1):540. doi: 10.1186/s13071-020-04419-1.

Abstract

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.

Keywords: Arboviruses; Blood-meal analysis; Chikungunya; Dengue; Mosquitoes; Non-human primates; Sylvatic cycles; Zika.

MeSH terms

  • Aedes / genetics
  • Aedes / virology
  • Animals
  • Antibodies, Viral / blood
  • Chikungunya Fever / transmission*
  • Chikungunya Fever / veterinary*
  • Chikungunya virus / genetics
  • Chikungunya virus / immunology
  • Chlorocebus aethiops / virology*
  • Dengue / transmission*
  • Dengue / veterinary*
  • Dengue Virus / genetics
  • Dengue Virus / immunology
  • Female
  • Humans
  • Hydroxymethylbilane Synthase / genetics
  • Mosquito Vectors / genetics
  • Mosquito Vectors / virology
  • Saint Kitts and Nevis
  • Zika Virus / genetics
  • Zika Virus / immunology
  • Zika Virus Infection / transmission*
  • Zika Virus Infection / veterinary*

Substances

  • Antibodies, Viral
  • Hydroxymethylbilane Synthase