GCSE biology unit 1 - vaccinations

vaccinations

protecting against future diseases

• vaccines contain dead pathogens that still have antigens (codes or shapes on the cell wall)
• the white blood cells will produce antibodies to attack the antigens
• in the future, if these pathogens enter the body, the white blood cells will be able to produce antibodies quicker as it will recognise the antigens

The more people that are vaccinated, the harder it is for the disease to spread as there are fewer people who can catch it.

MMR

• measles, mumps and rubella
• linked to autism (condition that effects people's communication and social interaction skills)

Ignas Semmelweis (1850s) noticed that there were fewer cases child bed fever (a common birth disease) in the wards where only the midwives worked and the were more cases of child bed fever in the wards where the medical students dealt with child birth. 

He noted that the medical students were also working on dead bodies whereas the midwifes only dealt with child birth. He also noted that the medical students didn't wash their hands after carrying out investigations on dead bodies.

He recorded results and there were indeed many more cases of the disease on the medical student wards. Semmelweis predicted that something from the dead bodies was passing on causing child bed fever. He asked the medical students to wash their hands and the number of deaths reduced but his ideas were rejected because he could not explain what was passing on. Nowadays we know this is bacteria and it is normal procedure for doctor and nurses to wash their hands continually.