Vaccines on trial

摘要

One of the largest ever vaccine studies is under way in Kolkata. Paroma Basu uncovers the benefits, and difficulties, of inoculating 60,000 people against cholera and typhoid fever. Famed for its poets and filmmakers, disgruntled Marxists and sleepy government clerks, Kolkata, a city of about 14 million people in northeastern India, may seem an unlikely setting for one of the largest clinical trials in the world. In the poorest areas of this city, residents live in homes jammed together along winding sewage-littered pathways and rely on shared toilets and drinking water. Typhoid fever and cholera are endemic in India, and are chronic problems in Kolkata. Cholera, in particular, has a tenacious grip on the state of West Bengal, often called the 'homeland of cholera.