Indonesian authorities began a major immunization campaign to vaccinate earthquake survivors on Wednesday after many complained aid had not arrived in their settlements.

According to government officials, health care workers would vaccinate more 130,000 children against measles. Another 1.3 million people would receive tetanus vaccines weeks after an earthquake that killed close to 6000 people in the country devastated their villages.

Although there have been no outbreaks of diseases, the World Health Organization (WHO) has expressed worries over isolated cases of tetanus infection.

WHO spokeswoman Harsaran Pandey tells Reuters, "Yesterday, we were given a figure of nine tetanus cases. And we also have been told there has been one death. We are waiting for a confirmation."

Previous WHO reports said many poor residents moved into poultry buildings, further deepening fears of possible bird flu contraction. Sanitation in the region is a major concern, given that many inhabitants now live in donated tents and tarpaulins outside.