Vaccinations

Vaccinations are an incredibly safe and effective way to protect children and adults from serious infections. A weakened or inactive version of the pathogen is given to stimulate an immune response. This immune response leads to immunity to the full version of the pathogen, reducing the risk and severity of infection with that pathogen.

Inactivated vaccines involve giving a killed version of the pathogen. They cannot cause an infection and are safe for immunocompromised patients, although they may not have an adequate response. Examples are:

• Polio
• Flu vaccine
• Hepatitis A
• Rabies

Subunit and conjugate vaccines only contain parts of the organism used to stimulate an immune response. They also cannot cause infection and are safe for immunocompromised patients. Examples of subunit and conjugate vaccines are:

• Pneumococcus
• Meningococcus
• Hepatitis B
• Pertussis (whooping cough)
• Haemophilus influenza type B
• Human papillomavirus (HPV)
• Shingles (herpes-zoster virus)

Live attenuated vaccines contain a weakened version of the pathogen. They are still capable of causing infection, particularly in immunocompromised patients. The following vaccines are live attenuated vaccines:

• Measles, mumps and rubella vaccine: contains all three weakened viruses
• BCG: contains a weakened version of tuberculosis
• Chickenpox: contains a weakened varicella-zoster virus
• Nasal influenza vaccine (not the injection)
• Rotavirus vaccine

Toxin vaccines contain a toxin that is normally produced by a pathogen. They cause immunity to the toxin and not the pathogen itself. Examples are the diphtheria and tetanus vaccines.

Vaccine Schedule

The UK vaccination schedule is constantly changing. It is also slightly different depending on when the child was born. Always look up the latest schedule when giving vaccines. Check the gov.uk website for the latest information.

Human Papillomavirus (HPV) Vaccine

The HPV vaccine is ideally given to girls and boys before they become sexually active. The intention is to prevent them contracting and spreading HPV once they become sexually active. The current NHS vaccine is Gardasil, which protects against strains 6, 11, 16 and 18:

• Strains 6 and 11 cause genital warts
• Strains 16 and 18 cause cervical cancer

TOM TIP: A common exam task is to counsel patients about their child receiving the HPV vaccine. They are often upset because they believe this implies their daughter or son is sexually promiscuous. Focus on the fact it needs to be given before they become sexually active and that it protects them from cervical cancer and genital warts. HPV is very common and infection is the number one risk factor for cervical cancer.

BCG Vaccine for Tuberculosis

The BCG vaccine is offered from birth to babies who are at higher risk of tuberculosis. These are babies with relatives from countries of high TB prevalence or who live in urban areas with a high rate of TB. It may also be given to children arriving from areas of high TB prevalence or in close contact with people that have TB.

MMR and Autism

Andrew Wakefield published a paper in 1998 in the Lancet, where he performed a series of tests on 12 children with autism and chronic enterocolitis. He reported it appeared they started having features of autism after the MMR vaccine. This was very anecdotal evidence based on parents perceptions about when the issues started. This caused a very big media response that generated a lot of fear amongst parents and uncertainty amongst doctors.

Since then the MMR vaccine, as well as other vaccines, have been extensively investigated with much more rigorous scientific research and statistical power, such as a meta-analysis with over one million patients. All subsequent scientific literature has disproved any link between the MMR and autism.

Last updated January 2026