Specific point mutations in the envelope protein of Tick-borne encephalitis virus enhance non-viraemic transmission efficiency in a tick vector

Abstract

Background: December 2007, some cases of dengue hemorrhagic fever were diagnosed in clildren in Rio de Janeiro, Brazil. Along the following months, the has ravaged the state, infecting more than 150,000 people with 232 suspected deaths. 42% of fatal cases were in children. The deaths showed us that the plasma leakage and shock are more common than hemorrhagic phenomena. In many cases, the presence of pleural, pericardial and peritoneal effusions were associated with a severe disease. The emergency rooms in the state were not capableto absorb the extra demand and causing the collapse of the healthcare system. The last outbreak in Rio de Janeiro was happen in 2002 with the serotype 3 and now the serotype 2 e 3 has been reported.Methods: On February 2008, a hundred of new dengue cases were being reported/ hour, so the health department of Rio the Janeiro State, the Mylitary Fire Corps and the Armed Forces assembled 7 field hospitals to support the emergency rooms, working with more 1000 health care providers. The average field hospital was equipped with an electronic blood cell counting machine, 30 beds for hydratation and 1 advanced ambulance. This intervention was based in the cocept of disaster medicine. The patients were triaged in the hospitals, had their blood taken for diagnosis, kept in observation and hydratated. The caes with deterioration were admitted to the hospital and if the patient got better, he was sent home.Results: The intravenous fluid administration during 12 hour observation period was associated with a decreased risk for the death and complications. On April, 29,000 cases were treated in the field hospitals and less than 2% of the patients were admitted to the emergency hospitals. Conclusion:The Field hospitals were a practical solution to reduce the mortality and morbility in this outbreak.

Tick-Borne Viruses and Biological Processes at the Tick-Host-Virus Interface

“…Specific mutations in the viral envelope protein of TBEV have been found to affect NVT between co-feeding I. ricinus for Siberian and European TBEV strains (Khasnatinov et al, 2010). Furthermore, it has recently been demonstrated that the structural genes of the European TBEV strain Hypr may determine high NVT rates of the virus between co-feeding I. ricinus ticks, whereas the region of the TBEV genome encoding non-structural proteins determines cytotoxicity in cultured mammalian cells (Khasnatinov et al, 2016).…”