Patterns of RNA virus infection and transmission within a wild simian zoonotic reservoir in Uganda

Patterns of RNA virus infection and transmission within a wild simian zoonotic reservoir in Uganda

James Lester

The context of viral transmission in Kibale National Park

Our reservoir of interest - Kibale red colobus

Viruses of interest: SIV and SFV

• SIV
  • Considerable variation in prevalence between populations, fluid transmission

  • Relatively low prevalences identified within Kibale RCB, as opposed to Taï and others

  • Associated with dominance rank in sooty mangabeys
• SFV
  • Consistently observed at high prevalence within RCB populations, salivary transmission
  • Maternal clustering identified within chimpanzees

Viruses of interest: SHFV(1/2) and SPgV

• SHFV(1/2)
  • Only recently identified in the wild, no previous epidemiology
  • Previously involved in research facility outbreaks, able to readily spread amongst infected hosts, not airborne
• SPgV
  • Similarly, only recently identified within wild-living primates, no previous epidemiology
  • Has a human analog - HPgV
  • Associated with presence of other blood-borne or sexually transmitted infections
  • Vertical transmission, either prenatal or during birth

Our approach

• Deep sequencing of blood samples from two red colobus troops
  • Allowing us to obtain full-length genomes for SHFV(1/2) and SPgV
  • Alongside clear identification of coinfections
  • Able to use sequencing not just as a diagnostic tool, but also to cluster infections
• Monthly behavioural scans for one of these groups over several consecutive days, with one focal red colobus troop
• Microsatellite data for each sampled individual

Our approach (cont.)

Key questions

• What are the demographic correlates of infection with these viruses?
• Do they associate with each other?
• Does infection with these viruses relate to patterns of behaviour?
• Can viral clustering be related to this?

Correlates of infection

Patterns of coinfection

Patterns of infection clustering

Behavioural correlates of infection

Behavioural correlates of infection clustering

Conclusions

• Indications of age-associated accumulation of infection in certain contexts - Particularly females
• Indications of both horizontal and (more tentatively) vertical transmission
• Co-infection with only the SHFV viruses indicated
• Association between agonistic, copulatory and associative behaviour and SHFV infection, not so for SPgV and SIV

Remaining questions and further work

• Low prevalence of SIV, and lack of association with dominance
• High SPgV prevalence with no association with dominance - Patterns of recovery and immunity?
• Why SHFV relates so strongly to patterns of agonism and other indications of social dominance?
• Requires further analysis of within-sample viral diversity
• Longitudinal viral sampling, for molecular clock calibration and potential dating of divergence

Acknowledgements