H.contortus survives in warm and moist conditions. Transmission periods are usually considered to be between 15-37 ◦C (Van Wyke and Reynecke 2011). The R0 model predicts when climate is going to be suitable for parasite transmission.
South Africa Climate:
A variable climate because if the large range of latitude and topography. Much of South Africa is in a temperate climate however there are deserts zones in the north west in addition to steppe zones in the north and north east. There are also some tropical regions to the east. This varying climate should be taking into considering when viewing our country wide Haemonchus graph. There is likely to be lower rainfall in areas particularly in the south and south west of South Africa due to climate change.