Risk factors for measles outbreak in Ataq and Habban districts, Shabwah governorate, Yemen, February to May 2018

Abstract

Background

Recent conflict and war in Yemen lead to collapse of the health system, decrease of immunization coverage and spread of many outbreaks. On May 22, 2018, the surveillance officer in Shabwah governorate reported an increased number of suspected measles. On May 24, 2018, a team from Yemen-Field Epidemiology Training Program was sent to investigate. The aims were to describe the outbreak, determine the risk factors for measles infection and recommend control measures.

Methodology

A descriptive followed by case-control study design (1:2 ratio) were performed. National Measles Surveillance Program case definition and predesigned questionnaire were used to collect data from 73 cases and 146 controls. Attack rate (AR), adjusted odds ratios (aOR) and 95% confidence intervals (95%CI) were calculated. P value < 0.05 was considered as the cut point for significant. Epi info version 7.2 was used.

Results

A total of 73 suspected cases were found. Almost 53% were from Habban district, 63% were males and 56% were among age group < 5 years. The overall AR was 82/100,000 population. Measles was significantly associated with contact with case (aOR = 27.3, 95% CI:1.3–551.7), malnourished children aged 6–60 months (aOR = 24.9, 95% CI;1.9–329.6) and unvaccinated children (aOR = 17.2, 95% CI:2.9–100.7). The six collected blood samples found to be positive for measles IgM.

Conclusions

Measles outbreak in Ataq and Habban districts was confirmed. Contact with measles cases, malnutrition and un-vaccination were the potential contributing factors of measles outbreak in Shabwah governorate. An urgent vaccination campaign with health education interventions are highly recommended. Reactivation of the outreach immunization services and strengthening surveillance and response systems are top priority to take place at district and governorate levels.