MEASLES OUTBREAK IN A RURAL AREA OF A DEVELOPING COUNTRY: A CASE CONTROL STUDY
Background: Measles is highly contagious vaccine preventable disease (VPD), and a major public health problem considered as leading cause of morbidity and mortality in developing countries like Pakistan. An outbreak of measles was reported in Sharifabad Islamabad on 15th of April 2017, and an investigation was launched to assess the magnitude of outbreak, evaluate risk factors and recommend control measures.
Methods: A comprehensive house to house active case search along with vaccine coverage survey was conducted from April 19-22, 2017. A case was defined as "onset of maculopapular rash with fever in a resident of Sharifabad with at least one of the following signs/ symptoms, Coryza, Conjunctivitis, Cough, Otitis media or Pneumonia present in between 19 March to 22nd April 2017". Four age & sex matched controls were selected from the neighborhood. Data was collected through interview method using structured questionnaire and vaccination coverage was determined by using Epi survey form. Blood samples were sent for laboratory confirmation.
Results: A total of eight cases were identified through active case finding while three were reported by local practitioner. Mean age of cases were 20 months (range 8-36 months). Severely affected age-group was 1-2 years with attack rate of 46%. Around two-third (64%) of cases and a few (16%) of controls were unvaccinated against measles. Contact with measles patient [OR 25.2, CI 3.9-160.1, P=0.00], unvaccinated children [OR 9.2 CI 2.12-40.4, P=0.000], social misconception regarding vaccination [OR 7.8 CI 1.42-42.6, P=0.00], and distance from healthcare facility [OR 5.7 CI 1.15-28.35, P=0.02] were significant risk factors. Vaccine efficacy was 90%.
Conclusion: Main reasons of the outbreak were contact with the cases, and low vaccination status. We recommended comprehensive measles vaccination and community awareness sessions. On our recommendations district health authority Islamabad carried out mop up of whole area.