Vaccines not kept at optimum temperatures in India
- India's vaccine cold chain system found dodgy
- Mandatory monitoring missing
- India’s vaccination programme is among the world's largest
Maintaining vaccines within the required temperature band is crucial as excessive heat or cold can make them ineffective. The WHO recommends vaccine storage between two and eight degrees Celsius.
The study led by Manoj Murhekar, senior scientist at the National Institute of Epidemiology, Chennai, tracked storage and delivery of the DPT (diphtheria, pertussis and tetanus) vaccine in 10 Indian states — selecting the largest district and the district most distant from the state capital in each.
The temperatures of vaccines exceeded eight degrees Celsius in several instances, for example, in the northeastern hilly state of Manipur. It fell below zero degree Celsius in others, as in Andhra Pradesh and Himachal Pradesh states, leading to the freezing of vaccines, says the report in the December issue of the Bulletin.
India runs one of the largest immunisation programmes in the world, targeting 27 million infants and 30 million pregnant women every year.
India's vaccine supply chain, extending from government supply points to primary or community health centres, is supposed to be covered by refrigerators and cold boxes with technicians maintaining necessary conditions at all stages along the way.
However, there are no mandatory checks on the potency of vaccines (as a reflection of cold chain maintenance), or on protection achieved after vaccination, says Madhavi Yenappu, principal scientist at the National Institute of Science, Technology and Development Studies, New Delhi. “I think, the maintenance of cold chain boils down to a governance issue at the primary healthcare centre,” she tells SciDev.Net.
Jacob John, former head of the department of virology, Christian Medical College, Vellore, adds that cold chain quality checks are part of inputs monitoring; and in the absence of such monitoring "we have made immunisation a ritual".
The report cites another study that examined 14 investigations on cold chain maintenance in developing countries. This review showed that more than 20 per cent of the refrigerators used for storage were faulty and that more than 35 per cent of vaccines were exposed to freezing temperatures while being shipped.
Link to the paper