Vaccines are linked to a wide variety of injuries from skin rashes to death. Like all drugs, vaccines can be dangerous. Compiling information about health conditions associated with vaccination is a major step to educating the public that there is indeed a risk of injury.
Most doctors would say that the risk of developing a condition like nerve damage is greater if you develop a disease like the flu then if you take the flu shot. This type of logic is faulty on the grounds that we simply do not have a measure of the true risk of developing a vaccine related injury. Independent large scale studies looking at the risk of vaccine injury are conducted with either flawed insurance database information or by using the Vaccine Adverse Event Reporting System (VAERS).
Every condition and drug has a code for insurance billing purposes. Researchers will look for the relevant codes for vaccines and a condition in a database and calculate the risk. This method is generally accepted yet fundamentally flawed. Not all conditions and drugs are coded correctly. For example, you can have someone get their third and final Gardasil shot two months before she goes to the hospital with nerve damage. If the doctor already charged the vaccine to insurance months or years ago then it is likely not show up as a vaccine injury. Also people who receive vaccines at free clinics or drug stores are excluded from this database.
Finally, most researchers agree that a database like VAERS is not suitable for true epidemiological study. The database provides not only little back up medical information, it is a completely voluntary system. VAERS is only meant to provide a signal that a real study needs to be conducted.
In order to measure the true risk of vaccine injury more healthcare providers and injured people need to file a report with VAERS. It is the only way to get properly funded studies on this topic.