Cholera: a re-emerging infection.

There is a global resurgence of cholera'. It is becoming an increasingly important public health challenge as the number of countries affected by this infection continues to increase. The current seventh pandemic is caused by V. cholerae 01, biotype EI Tor. This pandemic began in 1961 in Sulawesi, Indonesia and by 1966 has spread to other countries of Southeast Asia, Bangladesh, India, the former USSR, Iran and Iraq. The pandemic reached West Africa in 1970 and in 1991 affected South America where cholera had been absent for more than a centuty. This pandemic instead of abating is showing signs of further increasing. Nearly 120 countries had reported indigenous cases of cholera to WHO since 1991, and nearly half of those countries (including Malaysia) have reported cholera for at least five of the last eight years. In 1998, there was a dramatic increase in the number of cholera cases worldwide with the total number of cases almost twice that in 1997'. In Asia large increases in number of cases were reported from Afghanistan, India, Cambodia, Malaysia, Nepal and Sri Lanka. The number of cases of cholera in Malaysia from 1970 1998 is shown in Figure I.