Answer: No. Only vaccines that have been shown to be safe and effective when given together are administered at the same time. When new vaccines go through the extensive testing process, they are given along with all of the recommended childhood vaccines. Scientific studies assess the effect of giving these vaccines at the same time.
Children may receive several vaccines during the same clinic visit, but only after studies have shown that this is a safe practice. In order to receive a licence to combine vaccines, the manufacturer must also prove that the combined product does not make any of the vaccine components less effective or raise new safety concerns. Giving several vaccines at one time keeps children safe by protecting them against more diseases sooner. As an added benefit, it also reduces children's discomfort by reducing the number of injections they receive, and it saves parents the time and expense of additional office visits.