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Table 1 Summary of baseline (pre-control) modelled epidemiological scenarios

From: Modelling the impact of ivermectin on River Blindness and its burden of morbidity and mortality in African Savannah: EpiOncho projections

Pre-control endemicity Annual biting rate (ABR)§† Annual transmission potential (ATP)¶† Microfilarial prevalence in all ages Microfilarial prevalence in those aged ≥ 5 years Mean microfilarial intensity*in all ages (mf/mg) Mean microfilarial intensity*in those ≥ 20 yr (mf/mg)
Mesoendemic 7,300 88 40% 47% 11.2 18.7
Hyperendemic 15,470 373 60% 67% 23.9 40.0
Highly hyperendemic 85,800 4,290 80% 84% 58.9 98.0
  1. §Modelled annual biting rate (ABR): the average number of (S. damnosum s.str./S. sirbanum) bites to which a person is exposed during a whole year.
  2. Modelled annual transmission potential (ATP): the average number of infective larvae (L3) of O. volvulus potentially received during a whole year by a person exposed to the annual biting rate; model assumes perennial transmission.
  3. Both the ABR and ATP are for a proportion of vector blood meals of human origin equal to 0.3[21].
  4. Nodule prevalence (recorded by APOC) is converted to microfilarial load in this age range[36].
  5. *Arithmetic mean microfilarial load per mg of skin; note that this is different to the community microfilarial load (CMFL), which is the geometric mean microfilarial load per skin snip in those aged 20 years and above)[37].