Crimean-Congo Hemorrhagic Fever in Bulgaria

Abstract

We report the epidemiologic characteristics of Crimean-Congo hemorrhagic fever in Bulgaria, as well as the first genetic characterization of the virus strains circulating in the country in 2002 to 2003 that caused disease in humans.

Crimean-Congo hemorrhagic fever: History, epidemiology, pathogenesis, clinical syndrome and genetic diversity

“…Work in Bulgaria resulted in the development of a mouse brain-derived CCHF vaccine, which has been in use since the early 1970s, and the preparation of specific immune globulin from hyperimmunized volunteers, which is banked and utilized for treatment of patients (see sections on vaccines and therapy below). More than 1500 cases of CHF/CCHF were diagnosed in Bulgaria during the period 1953-2008(Papa et al, 2004. Human infections are seen principally in the eastern portion of the country in the spring and summer months, among men engaged in farming and other work involving tick exposure.…”

“…Nonetheless, immune globulin therapy was introduced in Bulgaria, where it remains in use (Vassilev et al, 1991;Papa et al, 2004;Christova et al, 2009). A 1990 article described the rapid improvement of patients treated with intramuscular and intravenous anti-CCHF immunoglobulin, but its efficacy has still not been assessed in a randomized clinical trial (Vassilenko et al, 1990).…”

“…Testing of serum samples from several thousand recipients demonstrated that repeated vaccination induced a low-level neutralizing antibody response; however, its protective efficacy was not evaluated (Tkachenko et al, 1971). A similar vaccine continues to be used in Bulgaria, where it is given to soldiers, medical personnel and other high-risk groups in endemic areas (Papa et al, 2004) . Sequencing showed that the Bulgarian V42/81 vaccine strain, isolated prior to 1970, is closely related to other viruses isolated in Bulgaria, Kosovo and Turkey .…”

Biosafety standards for working with Crimean-Congo hemorrhagic fever virus

“…A more recent detailed literature review of nosocomial CCHF transmission to HCWs listed 44 infections in 494 HCW contacts in 12 countries (Tarantola et al, 2007). Nosocomial infections were reported from South Africa Shepherd et al, 1985;Vandewal et al, 1985;Vaneeden et al, 1985a, b), Mauretania (Nabeth et al, 2004), Sudan (Elata et al, 2011), Albania (Harxhi et al, 2005;Papa et al, 2001), Kosovo (Papa et al, 2002), Bulgaria (Kunchev & Kojouharova, 2008;Papa et al, 2004), Turkey (Celikbas et al, 2014;Gürbüz et al, 2009), Iran (Chinikar et al, 2013;Mardani et al, 2009;Naderi et al, 2013), Dubai (Suleiman et al, 1980), Pakistan (Burney et al, 1980;Hasan et al, 2013), India , Tajikistan (ProMED-mail, 2009b), Kazakhstan (ProMED-mail, 2009a) and Germany (Conger et al, 2015).…”

Using of ELISA in Diagnosis of Crimean-Congo Hemorrhagic Fever Virus, a Case Report

“…Initially involving the nervous system, disease may in severe cases progress to vascular disorders such as profuse diapedesis hemorrhages, brain edema, general malaise, and ultimately cardiac arrest (Wilson et al, 1990). The major transmission of the virus is mediated by Hyalomma ticks; it can also be transmitted by squashing ticks, contact with contaminated secretions, blood and sera of patients and viremic animals (Swanepoel et al, 1987;Bosan et al, 2000;Burt et al, 1997;Whitehouse, 2004;Chinikar et al, 2004;Papa et al, 2004). Health workers, relatives of CCHF patients, people working with animals and animal products (shepherds, animal care workers, veterinarians and slaughterhouse workers) and people that had tick bites in CCHF endemic areas are under high risk of being infected by CCHF.…”