And health systems in many countries were struggling with the current vaccines they were trying to deliver.

If it works, the combination vaccine could be a major advance from current vaccines, which require multiple injections.

Unfortunately, today's public health officials do not encourage a well-rounded debate on the risks of current vaccines.

The current vaccine is ineffective for children under age 2.

The current vaccine would not be expected to protect against "bird flu" influenza.

No one knows how long the immunity induced by the current vaccine will last.

The current vaccine is made from whole pertussis bacteria cells that have been killed.

For many diseases, current vaccines fail to offer complete protection.

World Health officials estimate that it costs $10 to $15 to fully immunize a child with current vaccines, a total of $1.5 billion year.

None of these people can be given the current vaccine, which uses a live virus.