High fatality rates and associated factors in two hospital outbreaks of MERS in Daejeon, the Republic of Korea

Int J Infect Dis. 2017 May:58:37-42. doi: 10.1016/j.ijid.2017.02.008. Epub 2017 Feb 20.

Abstract

Objectives: To explore the epidemiological and clinical factors predictive of the case fatality rate (CFR) of Middle East respiratory syndrome-coronavirus (MERS-CoV) infection in an outbreak in Daejeon, the Republic of Korea.

Methods: We reviewed the outbreak investigation reports and medical records of 1 index case and 25 additional MERS cases in hospitals A (14 cases) and B (11 cases), and conducted an in-depth interview with the index case.

Results: The CFR in hospital B was higher than that in hospital A (63.6% vs. 28.6%, respectively). Higher MERS-CoV exposure conditions were also found in hospital B, including aggravated pneumonia in the index case and nebulizer use in a six-bed admission room. The host factors associated with high CFR were pre-existing pneumonia, smoking history, an incubation period of less than 5 days, leukocytosis, abnormal renal function at diagnosis, and respiratory symptoms such as sputum and dyspnea.

Conclusions: The conditions surrounding MERS-CoV exposure and the underlying poor pulmonary function due to a smoking history or pre-existing pneumonia may explain the high CFR in hospital B. The clinical features described above may enable prediction of the prognosis of MERS cases.

Keywords: Hospital; Korea; Middle East respiratory syndrome coronavirus; Mortality; Outbreak.

MeSH terms

  • Adult
  • Aged
  • Coronavirus Infections / epidemiology
  • Coronavirus Infections / mortality*
  • Cross Infection / epidemiology
  • Cross Infection / mortality*
  • Disease Outbreaks*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Middle East Respiratory Syndrome Coronavirus*
  • Republic of Korea / epidemiology
  • Risk Factors