Immunization is one of the most powerful and cost-effective of all health interventions. It prevents debilitating illness and disability, and saves millions of lives every year. It is also key to achieving the Millennium Development Goals (MDGs) – commitments made by world leaders in 2000 to reduce poverty and improve human development. The contribution of immunization is especially critical to achieving the goal to reduce deaths among children under five years old (MDG 4).1 The cold chain system introduced by World Health Organization (WHO) is a system to transport and store vaccine in the potent condition starting from the time it is manufactured to the time it is administered to patients in specified temperature range of (2-8℃). In many countries, studies found that improper vaccine storage and handling were cited as possible causes of many measles outbreaks in early 1990's)1. In Malaysia, measles cases increased drastically with incidence rates of 11.48 and 26.59 per 100,000 populations despite wide coverage of immunization in 1999 (86.6%) and 2000 (88%) ). In these two years, measles outbreak took place all around the country including urban and rural areas. The Ministry of Health has suggested that the outbreak were due to primary vaccine failure and failure to vaccinate, causing accumulation of susceptible individuals.2
