Abstract. We investigated the possibility of transmission of Crimean-Congo hemorrhagic fever (CCHF) virus through respiratory and physical contact. In this prospective study, we traced 116 close relatives of confirmed CCHF cases who were in close contact with the patients during the acute phase of the infection and evaluated the type of contact between patients and their relatives. These relatives were followed for clinical signs or symptoms indicative of CCHF disease, blood samples of those with and without clinical signs were analyzed for CCHF virus immunoglobulin M and G (IgM and IgG, respectively) by enzyme-linked immunosorbent assay. No close relatives developed any signs or symptoms of CCHF and were negative for CCHF virus IgM and IgG. The results suggest that CCHF virus is not easily transmitted from person to person through respiratory or physical contact.Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne disease caused by CCHF virus (CCHFV), which belongs to the Bunyaviridae family, and Nairovirus genus.1,2 Human infections begin with nonspecific febrile symptoms but progress to a serious hemorrhagic disease. In severe cases, circulatory shock and disseminated intravascular coagulation may occur and result in death. [3][4][5][6] The fatality rate attributed to this infection is between 3% and 30%. 4,5,7,8 The CCHFV is generally transmitted to humans through the bite of Ixodid ticks or by contact with blood or tissue of infected livestock.3,5 Human-to-human transmission has been reported only by direct contact with viremic patients during the acute phase of infection. Needle stick injuries, gastrointestinal hemorrhage interventions, emergency surgical procedures, and unsafe handling of patients or their infected materials have been reported to be high-risk activities for CCHFV transmission; however, transmission through droplet, viral droplet, or physical contact has not been definitely tested.9-14 Moreover, transmission may occur by respiratory contact. 1 We conducted a prospective contact tracing study to investigate the possibility of CCHFV transmission through respiratory contact, including droplet and airborne, and ungloved physical contact with the patient or objects around the patient.This study was conducted at the Cumhuriyet University Hospital in Turkey, between June and September 2011. The CCHF patients were generally referred to our hospital 2-5 days after the initial onset of disease symptoms. This delay was primarily because of non-specific symptoms on the first several days of the infection. After confirmation of CCHF infection, the first degree relatives from the same household were identified and types of repeated contact between patients and their relatives were recorded. Some of these relatives were allowed to remain in the same hospital room as caregivers, because many patients and their relatives came from outside the city, had strong emotional ties and fear of death, and the relatives desired to be near the patients during what might be their last days; however, the use of prote...