Influence of laboratory animal hosts on the life cycle of Hyalomma marginatum and implications for an in vivo transmission model for Crimean-Congo hemorrhagic fever virus

Crimean-Congo hemorrhagic fever virus (CCHFV) is one of the most geographically widespread arboviruses and causes a severe hemorrhagic syndrome in humans. The virus circulates in nature in a vertebrate-tick cycle and ticks of the genus Hyalomma are the main vectors and reservoirs. Although the tick vector plays a central role in the maintenance and transmission of CCHFV in nature, comparatively little is known of CCHFV-tick interactions. This is mostly due to the fact that establishing tick colonies is laborious, and working with CCHFV requires a biosafety level 4 laboratory (BSL4) in many countries. Nonetheless, an in vivo transmission model is essential to understand the epidemiology of the transmission cycle of CCHFV. In addition, important parameters such as vectorial capacity of tick species, levels of infection in the host necessary to infect the tick, and aspects of virus transmission by tick bite including the influence of tick saliva, cannot be investigated any other way. Here, we evaluate the influence of different laboratory animal species as hosts supporting the life cycle of Hyalomma marginatum, a two-host tick. Rabbits were considered the host of choice for the maintenance of the uninfected colonies due to high larval attachment rates, shorter larval-nymphal feeding times, higher nymphal molting rates, high egg hatching rates, and higher conversion efficiency index (CEI). Furthermore, we describe the successful establishment of an in vivo transmission model for CCHFV in a BSL4 biocontainment setting using interferon knockout mice. This will give us a new tool to study the transmission and interaction of CCHFV with its tick vector

An early warning system for Crimean-Congo haemorrhagic fever seasonality in Turkey based on remote sensing technology

Abstract. In the last few years, Crimean-Congo haemorrhagic fever (CCHF) has been reported as an emerging tickborne disease in Turkey. This paper deals with the preparation of an early warning system, aimed to predict the beginning of the CCHF season in Turkey based on a clear, simple and repeatable remotely-sensed signal. Decadal (mean of 10 days) values of the normalized difference vegetation index (NDVI) at 1 km resolution were used on a set of 952 confirmed, accurately geo-referenced, clinical cases between 2003 and 2006. A prerequisite is that the signal should be observable between 2 and 3 decadals before a given moment of the season to be of value as early warning. Decadals marking the 10 th percentile or the 25 th quartile in the frequency distribution of case reporting were selected as markers for the beginning of season of risk. Neither raw nor accumulated decadal NDVI signals were able to predict the onset of this season. However, when we defined the NDVI anomaly (NDVIa) as the positive difference between decadal NDVI values and the average for the previous year, this standardized measure gave a homogeneous overview of the changes in the NDVI signal producing a NDVIa slope for the decadals 10 to 13 that was always greater than 0. We conclude that observing this slope over time can be used as an early-warning system as it would predict the build-up of the number of cases 20 days in advance with an accuracy of 82 % (10 th percentile) or 98 % (25 th quartile). Keywords: Crimean-Congo haemorrhagic fever, early warning, Turkey, normalized difference vegetation index, remote sensing

DETECTION OF TOXOPLASMA GONDII FROM MEAT AND MEAT PRODUCTS BY THE NESTED-PCR METHOD AND ITS RELATIONSHIP WITH SEROPREVALENCE IN SLAUGHTERED ANIMALS

Toxoplasma gondii DNA was detected at rates of 2%, 6%, 4.17%, 20%, and 19% in 50 bovine brains, 50 bovine muscles, 120 ovine brains, 20 ovine muscles, and in 100 fermented sausage samples, respectively. Sequenced positive samples showed 100% identity with T. gondii RH strain. Seropositivity rates were detected as 24% in cattle and 25% in sheep slaughtered in local slaughterhouses. The detection of the parasite in uncooked meat and commercial meat products, and the high ratio of seropositive slaughtered animals, emphasise that the risk still exists for food-transmitted toxoplasmosis. This is the first report horn Turkey describing the detection of Toxoplasma gondii in food using the molecular method

The Effects of Nitric Oxide and Inhibitor, and Combination of Albendazole and Praziquantel On Liver in Mice Injected with Echinococcus granulosus Larvae.

In this study, the role of nitric oxide (NO) in the pathogenesis of hydatidosis and the interaction with effects of anthelmintic drugs, albendazole and praziquantel, were examined in larval infection caused by protoscolices obtained from hydatid cysts of sheep liver in Albino Balb/c mice