Vector borne and zoonotic diseases
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Vector Borne Zoonotic Dis. · Sep 2012
Seroprevalence of Crimean Congo hemorrhagic fever virus in Ijara District, Kenya.
Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne viral disease mainly affecting pastoralists who come in contact with animals infested with Hyalomma ticks, which are the key vectors of CCHF virus (CCHFV). CCHFV has been detected among these ticks in parts of North Eastern Kenya. This study aimed to identify acute cases of CCHF, and to determine the extent of previous exposure to CCHFV in an outpatient population attending Sangailu and Ijara health centers, Ijara District, North Eastern Kenya, presenting with acute febrile illnesses. ⋯ Age, location, and contact with donkeys were significantly associated with exposure to CCHFV. Acute CCHFV infections could be occurring without being detected in this population. This study confirms human exposure to CCHF virus in Ijara District, Kenya, and identifies several significant risk factors associated with exposure to CCHFV.
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Vector Borne Zoonotic Dis. · Jan 2012
Case ReportsMolecular diagnosis of Leishmania mexicana in a cutaneous leishmaniasis case in Sinaloa, Mexico.
Leishmaniasis has been considered endemic in Sinaloa, Mexico, since 1994. Despite that Leishmania mexicana is the main etiological agent of cutaneous leishmaniasis (CL) in other regions of Mexico, the species causing CL in patients from Sinaloa state has not been previously established, although Leishmania braziliensis has been found in the neighboring southern state, Nayarit. ⋯ Due to the implications on individual and public health, the objective of this report was to identify the Leishmania species present in Sinaloa, Mexico. Using the first internal transcribed spacer (ITS-1) polymerase chain reaction-restriction fragment length polymorphism, we identified L. mexicana in a CL patient from Sinaloa and confirmed the extended distribution of this parasite in Mexico.
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Vector Borne Zoonotic Dis. · Jan 2012
Prevalence of Buggy Creek virus (Togaviridae: Alphavirus) in insect vectors increases over time in the presence of an invasive avian host.
Invasive species can disrupt natural disease dynamics by altering pathogen transmission among native hosts and vectors. The relatively recent occupancy of cliff swallow (Petrochelidon pyrrhonota) nesting colonies in western Nebraska by introduced European house sparrows (Passer domesticus) has led to yearly increases in the prevalence of an endemic arbovirus, Buggy Creek virus (BCRV), in its native swallow bug (Oeciacus vicarius) vector at sites containing both the invasive sparrow host and the native swallow host. ⋯ Increased BCRV prevalence in bug vectors at mixed-species colonies may reflect high virus replication rates in house sparrow hosts, resulting in frequent virus transmission between sparrows and swallow bugs. This case represents a rare empirical example of a pathogen effectively switching to an invasive host, documented in the early phases of the host's arrival in a specialized ecosystem and illustrating how an invasive species can promote long-term changes in host-parasite transmission dynamics.
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Vector Borne Zoonotic Dis. · Dec 2011
ReviewThe status of Rift Valley fever in animals in Saudi Arabia: a mini review.
In August-September 2000, an overwhelming outbreak of Rift Valley fever (RVF) struck the southwestern part of Saudi Arabia and adjoining Yemeni territories. During the outbreak, which was the first ever to be recorded outside Africa, around 40,000 animals, mostly sheep and goats, died or aborted and 883 cases, with 124 deaths, were recorded among humans in Saudi Arabia. An additional 1328 human cases, with 166 deaths, were concurrently recorded in northwestern Yemen. ⋯ However, the virus persisted in a cryptic form in the original area of the epizootic, resulting in intermittent diagnosis of few cases throughout the past 10 years. To date, however, no evidence was found of virus activity outside that area. This review provides, from a veterinary perspective, a brief account of the events surrounding the epizootic and its present status in Saudi Arabia and emphasizes the need for vigilance, preparedness, and regular monitoring of the disease by serosurveillance methods.
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Vector Borne Zoonotic Dis. · Oct 2011
Crimean-Congo hemorrhagic fever virus in ticks collected from humans, livestock, and picnic sites in the hyperendemic region of Turkey.
During June and July 2007, about 3125 adult ticks were collected from humans, animals, and vegetation in a hyperendemic region (Sivas and Tokat) of Turkey. A total of 2193 ticks were pooled in 225 pools and screened for the Crimean Congo hemorrhagic fever virus (CCHFV) presence by antigen-capture enzyme-linked immunosorbent assay. Infection rates were calculated as the maximum likelihood estimation with 95% confidence intervals (CI). ⋯ Maximum likelihood estimation values of CCHFV in H. marginatum ticks collected from human, cattle, and sheep were 0.91% (CI 0.05-4.42), 2.10% (CI 1.12-3.64), and 3.11% (CI 1.18-6.87), respectively. CCHFV antigens were also demonstrated in Hyalomma excavatum, Haemaphysalis parva, and Boophilus annulatus ticks collected from cattle and Rhipicephalus bursa ticks from sheep. Our results suggest that the studied area might maintain its endemic properties in the near future unless effective tick control measures are implemented.