Study design and sample collection
The study design and sampling collection are described in detail
elsewhere (Falzon et al., 2019). Briefly, four LMs and neighbouring SHs
were selected in each county (Figure 1), where each LM was closely
associated with a cattle or pig SH. At each LM, 10 animals (six cattle,
three goats, and one sheep) were selected via systematic random
sampling. We attempted to select six cattle, three goats, and one sheep
during each visit, though the number of animals sampled did not always
follow the above ratio as it was occasionally challenging to get consent
from owners of small ruminants. Signed consent was sought from the
animal owners or traders accompanying sampled animals, and a short
questionnaire was administered to capture demographic and animal
ownership details. Animals were then physically restrained and, after a
general clinical examination, blood was drawn by a qualified
veterinarian from the jugular vein using a vacutainer. Nasal swabs and
faecal samples were also collected. Any external parasites present on
the hide of the selected animals were removed with gloved hands and
placed into falcon tubes containing 70% ethanol. At cattle and pig SHs,
a similar procedure was followed. In addition to ticks, lice and fleas
were collected if present on sampled animals. Sample bottles and blood
tubes were barcoded and transported to the field lab in Busia in a cool
box with ice packs. Arthropods were stored at -40°C at the International
Livestock Research Institute (ILRI) Department of Veterinary Services
lab in Busia before being shipped on dry ice to the Martin Lüscher
Emerging Infectious Diseases (ML-EID) laboratory at the International
Centre of Insect Physiology and Ecology (icipe) where they were
stored at -80°C.