Infection and immunity
Infection and immunity

This free course is available to start right now. Review the full course description and key learning outcomes and create an account and enrol if you want a free statement of participation.

Free course

Infection and immunity

Summary to Section 2

In Session 2 you have been introduced to the concept of the scientific method and should now appreciate how useful it has been in combating infectious disease. The power of using systematic observation to identify correlations and develop testable hypotheses is well illustrated by the story of John Snow and the 1854 cholera outbreak in London. This example also underlines the terrible effect of pollution on human health – in particular as a cause of water-borne infectious diseases – and the utility of concerted public health campaigns.

Through a second historical tale, the example of Edward Jenner and smallpox, you have also learned about vaccination and its capacity to fight infectious disease. As we have described, the success of vaccination against smallpox has been absolute and the WHO have declared smallpox to be globally eradicated.

However, the war against infectious disease is far from over. Although effective vaccines now exist against diphtheria, measles, polio and several other infectious diseases, current vaccines against some others, including cholera, are only weakly effective or short-lasting. In 2015, there were still no effective vaccines against several life-threatening infections, including HIV/AIDS, but a vaccine against malaria was looking promising and the first Ebola vaccine proved highly effective in initial trials (Henao-Restrepo et al., 2015). Another problem is illustrated by influenza viruses, which change their structural features so rapidly that this year’s flu vaccine may not give protection against the viruses in circulation next year. And as you have learned, although entirely preventable, pollution remains a major source of water-borne infectious diseases in much of the developing world today. Thus, effective strategies to combat infectious disease remain as relevant today as in Jenner’s era.

You can now go to Session 3 [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] .

SDK100_1

Take your learning further

Making the decision to study can be a big step, which is why you'll want a trusted University. The Open University has over 40 years’ experience delivering flexible learning and 170,000 students are studying with us right now. Take a look at all Open University courses.

If you are new to university level study, find out more about the types of qualifications we offer, including our entry level Access courses and Certificates.

Not ready for University study then browse over 900 free courses on OpenLearn and sign up to our newsletter to hear about new free courses as they are released.

Every year, thousands of students decide to study with The Open University. With over 120 qualifications, we’ve got the right course for you.

Request an Open University prospectus