29/03/2014 GMT

The BBC�s monthly Health Check with Claudia Hammond and Dr Ayan Panja focuses on the latest efforts to control diseases which are making an unwelcome comeback.
The polio virus can cause paralysis - and we are getting closer to eradicating the devastating disease. But last year Syria saw its first outbreak for 14 years, putting the whole of the Middle East at risk. Now a mass vaccination programme is targeting refugees crossing the Syrian border.
South Africa is one of only two countries in the world where tuberculosis is on the increase - thanks to drug resistance. Researchers are now able to identify those patients who are most likely to spread the disease by coughing because of a new piece of equipment.
And - how sick dogs are helping research into human health.