Indigenous malaria has been recorded as far north as 64°N latitude (Archangel in the former USSR) and as far south as 32°S latitude (Cordoba in Argentina). It has occurred in the Dead Sea area at 400 m below and at 2800 m above sea level in Cocha-Mbamba (Bolivia). Within these limits of latitude and altitude there are large areas free of malaria, which is essentially a focal disease, because its transmission depends greatly on local environmental and other conditions.