Public Health Fellowship Program Field Epidemiology Tra ck

Public Health Fellowship Program – Field Epidemiology Tra ck 6 th East African Health and Scientific Conference A measles outbreak propagated by children congregating at water collection points: Mayuge District, Eastern Uganda, October 2016 Robert K. Majwala, MD MA, Fellow Cohort 2016 Lydia Nakiire Daniel Kadobera

Measles outbreak Reported § 14 th Oct. 2016, Mo. H notified of a measles outbreak in Mayuge District § 3/10 samples tested measles Ig. M+ § District Health Team reported increased numbers of children with fever and rash in the district since Aug. 2016 2 Mayuge Measles Investigation, Oct. 2016

Objectives § To determine outbreak’s extent and risk factors § Evaluate vaccination coverage and vaccine effectiveness § Recommend evidence based control measures 3 Mayuge Measles Investigation, Oct. 2016

Case Definitions § Probable case: Fever ≥ 3 days and generalized rash with ≥ 1, conjunctivitis, cough or running nose § Confirmed case: Probable case with measles Ig. M(+) in absence of vaccination in last two weeks 4 Mayuge Measles Investigation, Oct. 2016

Case finding process We found cases by reviewing medical records at health facilities We found cases in the community with the community leaders Cases found Cases Count Probable 59 Confirmed 3 Total 62 5 Mayuge Measles Investigation, Oct. 2016

Attack rates similar across different characteristics Characteristics Age (Months) Count Population AR/10, 000 Age 0 - 11 9 6, 672 13 12 - 59 38 24, 671 15 60+ 15 123, 818 1. 2 Kityerera 20 49, 330 4. 1 Malongo 42 105, 831 4. 0 Males 32 73, 736 4. 3 Females 30 76, 810 3. 9 Subcounty Sex 6 Mayuge Measles Investigation, Oct. 2016

Propagated Transmission 7 Mayuge Measles Investigation, Oct. 2016

Case Control Study § § § Case-Control Study Approximate case : control ratio of 1: 4 41 cases: 161 controls Matched by age and residence Collected risk factor information including vaccination status during effective exposure period i. e. 7 – 21 days before onset of rash 8 Mayuge Measles Investigation, Oct. 2016

Children Gathering at water collection Points Significantly Associated with Measles Risk Factor Measles vaccination (9 – 59 months) Going to water collection point (6 – 59) months Cases n=31 Controls n=121 ORMH (95% CI) 39% 68% 0. 31 (0. 12 – 0. 75) 32% 13% 5. 0 (1. 5 – 17) 9 Mayuge Measles Investigation, Oct. 2016

Estimation of Vaccine Effectiveness and vaccination coverage Vaccine Effectiveness Vaccination coverage § § § 68% (95% CI: 61 – 76) § Below the recommended at least 80% target for a district ���� =�� −���� " ≈" ���� protective for rare diseases VE = (1 - 0. 31)*100 = 69% (95% CI: 25 – 88) 10 Mayuge Measles Investigation, Oct. 2016

Conclusion and recommendations § Exposure to infectious case patients at water collection sites, together with suboptimal vaccine effectiveness and low vaccination coverage helped propagate this measles outbreak § We recommended the following; – Advised parents and other community members to avoid & discourage taking & sending sick children & infants to water collection points – Measles surveillance in the district was strengthened – We recommended introduction of a second dose of measles to improve vaccine effectiveness – Intensify vaccination services provision in the affected sub-counties 11 Mayuge Measles Investigation, Oct. 2016

Public Health Fellowship Program – Field Epidemiology Tra ck Acknowledgment § § § District Health Team Mayuge District US CDC Makerere School of Public Health Emergency Operations Centre – MOH Uganda Virus Research Institute Uganda Public Health Fellowship Program Secretariat