Nosocomial Transmission of Crimean-Congo Hemorrhagic Fever (CCHF) from a US Soldier
Amesh A. Adalja, MD, FACP, FACEP, December 5, 2014
Hemorrhagic fever viruses are generally not as contagious as many other pathogens—such as those that spread primarily by a respiratory route—but they pose considerable infection control challenges because of the amount and type of blood and bodily fluids they induce patients to emit. Crimean-Congo Hemorrhagic Fever (CCHF) virus, a tickborne pathogen endemic in many parts of the world, is one such virus. The case of a US soldier who was fatally infected with CCHF illustrates several important points about caring for hemorrhagic fever patients that are directly applicable to Ebola and other similar viruses.
Infection in Afghanistan
A US soldier working in Kandahar City, Afghanistan, in 2009 presented for care after having experienced fever and gastrointestinal symptoms for several days. The patient was diagnosed with gastroenteritis, prescribed an antibiotic, and released. His condition had worsened by the next day, and he was admitted to the hospital. Testing for CCHF was performed upon admission and returned positive on the 7th day of illness. The patient’s clinical condition had deteriorated to the point that he had developed multi-organ dysfunction requiring multiple heroic interventions, including mechanical ventilation, hemodialysis, and liver dialysis. The antiviral ribavirin was administered. Despite these measures, the patient succumbed to CCHF. Of note, until the patient was confirmed to have CCHF, only standard infection control measures were in force.
Since CCHF can be spread through direct contact with blood and bodily fluids, contact tracing was commenced. Three tiers of exposure were identified encompassing 90 individuals, 18 of whom were offered oral ribavirin as postexposure prophylaxis (PEP). Of the contacts, 2 were of special concern: an ICU nurse and a respiratory therapist who had higher-risk exposure to the patient including manual bag-valve ventilation. Both of these individuals were subsequently found to have seroconverted to CCHF when a serosurvey was later performed. Both individuals seroconverted while receiving ribavirin PEP. They were both noted to have mild symptoms during treatment that were attributed to the ribavirin at the time but which in fact may actually have been CCHF blunted by the ribavirin.
Hemorrhagic fever viruses—whether Ebola, Lassa, Marburg, or CCHF—are unforgiving of lapses in infection control. The fact that these viruses are primarily transmitted from person to person by contact with blood and bodily fluids hampers their ability to spark large-scale epidemics, but it does not greatly reduce the risk of infection to healthcare workers who are not wearing appropriate PPE. Such risk is magnified when dealing with patients who are critically ill and receiving invasive procedures in which blood and bodily fluid exposure is the norm. Like the 2 American nurses who were infected with Ebola while caring for a critically ill patient, these 2 CCHF-infected healthcare workers exemplify how essential infection control protocols are and how difficult it may be for all hospitals to implement them without fail.
Conger NG, Paolino KM, Osborn EC, et al. Health care response to CCHF in US soldier and investigation of nosocomial transmission to health care providers, Germany, 2009. Emerg Infect Dis 2015. http://dx.doi.org/10.3201/eid2101.141413. Accessed December 3, 2014.