The Prevnar vaccine has had no serious or permanent side effects noted. However, there is a significant risk of a fever and a slight risk (2 percent) of a high fever over 102ºF. Our own daughter suffered from this side effect and despite our reassurances, our wife stopped giving her this vaccine after two doses when each dose was followed by a fever of 103ºF. There is also a one in four chance of a mild side effect such as redness, tenderness, or swelling at the injection site.
The Pneumovax is a very safe vaccine, with less than 1 percent of recipients developing anything more than a sore arm. Unfortunately, despite its safety, it is not effective in children under age two and thus cannot be used in infants.