While we will have an emergency medical kit with us, and the satelite phone enables remote medical assistance, there can be cases where lack of immediate help can lead to serious consequences. To reduce the risk of medical emergencies, all participants are requested to have a checkup before the trip. The former are deadly, but are rare and easily avoidable. They leave distinct tracks in the sand, do not actively seek humans, and typically stay dormant in the cooler autumn to spring months. Though both my and other's experience is that only tracks are seen, live snakes very rarely, we will have antivenom with us, just in case.
Scorpions are more common, but less deadly.
Though they tend to shy humans, occasionally they crawl under tents or into one's shoes outside, so it's wise to shake one's shoes in the morning before putting them on. The Western Desert was the scene of one of the fiercest fighting in WW II., and the northern coast and the Qattara depression was heavily mined. Though most were cleared along the coast, inland any number may remain. Given this situation, all parts of the Qattara depression outside travelled roads and tracks are better left in peace. The Long Range Desert Group was also active further south, and they have mined most of the tracks leading to Kufra and Uweinat on the Libyan side.