Retrospective, epidemiological cluster analysis of the Middle East respiratory syndrome coronavirus (MERS-CoV) epidemic using open source data.

The Middle East respiratory syndrome coronavirus (MERS-CoV) is caused by a novel coronavirus discovered in 2012. Since then, 1806 cases, including 564 deaths, have been reported by the Kingdom of Saudi Arabia (KSA) and affected countries as of 1 June 2016. Previous literature attributed increases in MERS-CoV transmission to camel breeding season as camels are likely the reservoir for the virus. However, this literature review and subsequent analysis indicate a lack of seasonality. A retrospective, epidemiological cluster analysis was conducted to investigate increases in MERS-CoV transmission and reports of household and nosocomial clusters. Cases were verified and associations between cases were substantiated through an extensive literature review and the Armed Forces Health Surveillance Branch's Tiered Source Classification System. A total of 51 clusters were identified, primarily nosocomial (80·4%) and most occurred in KSA (45·1%). Clusters corresponded temporally with the majority of periods of greatest incidence, suggesting a strong correlation between nosocomial transmission and notable increases in cases.

Contribution of rural-to-urban migration in the prevalence of drug resistant tuberculosis in China.

Increased drug resistance rates to the first-line anti-tuberculosis drugs and multidrug resistance (MDR) were observed in China. The objectives of this study were to determine the prevalence and risk factors for drug-resistant tuberculosis (TB) in urban China and, more specifically, to determine the contribution of migration to case burden and drug resistance rates of urban cities. A facility-based epidemiological study of all active TB patients reported in the four districts of Shanghai and Ningbo between April 1, 2008 and March 31, 2009 was conducted. Residents had significantly higher drug-resistance rates than migrants (any drug resistance: 29.8% vs. 23.5%, respectively, P = 0.038; MDR: 10.9% vs. 6.1%, P = 0.048). Previously treated migrant patients were more likely to harbor drug-resistant TB and MDR-TB than new migrant cases, with adjusted odds ratios of 3.85 and 6.52, respectively. In total, 46.2% of the previously treated cases were resistant to INH, 38.5% to SM, 33.3% to RMP and 30.8% to EMB, while 13.1%, 17.5%, 7.0% and 6.8% of new cases were resistant to the four agents, respectively. To prevent the transmission of drug-resistant TB among migrants and residents, improved case management and appropriate treatment regimens should be sustained to prevent acquired drug resistance.