Assessing Onchocerca volvulus intensity of infection using mitochondrial sequence data
Skin snips were collected from people with epilepsy, incubated for 24 h in isotonic saline to allow emergence of microfilariae, and transferred to 80% ethanol. The ethanol solution containing the microfilariae was transferred into a 15ml falcon tube, filled to 15ml with MilliQ water, and centrifuged at 500g for 5min. Approximately 14 ml was aspirated carefully from the tube, leaving the microfilarial pellet in approximately 1 mL. This was transferred into a clean glass petri dish and each individual microfilaria was picked by aspiration using a pipette into 20 L lysis buffer. Sequencing libraries were constructed using the NEBUltra kit barcoded using unique dual indexes, according to the manufacturers instructions (New England Biolabs, Ipswitch, Massachusetts, USA).