A special round of Mission Indradhanush, an immunisation programme initiated by the Centre, was launched in the district on Tuesday to cover children and pregnant mothers left out during the previous rounds. Camps would be conducted in all primary health centres till July 13, Collector K.S. Palanisamy has said. Mission Indradhanush, depicting seven colours of the rainbow, aims at covering all those children who are either unvaccinated or are partially vaccinated against seven vaccine preventable diseases such as diphtheria, whooping cough, tetanus, polio, tuberculosis, measles, and Hepatitis B.