Table 4 Group 1 (Trekkers) - Subjects arriving at each laboratory and reasons for absence from laboratory

No of Trekkers Arriving at Laboratory

198

197

195

190

Reason for Absence from Laboratory

- gender, age, expedition day

nil absent

Respiratory Tract infection (1)

M, age 73, Day 1

Abcess (1)

M, age 49, Day 3

AMS (1)

F, age 55, Day 3

AMS (1)

F, Age 39, Day 10

Angina (1)

F, age 60, Day 7

Respiratory Tract Infection (1)

M, age 68, Day 7

Diarrhoea and Vomiting (1)

F, age 59, Day 10

Recurrent Cluster Headache (1)

M, age 62, Day 8