Infection of Feral Phenotype Swine with Japanese Encephalitis Virus

Understanding the Burden of Agriculturally Significant Vector-Borne and Parasitic Diseases in Kansas

Background: The state of Kansas (KS) has been called the "agricultural heartland" of the United States. Vector-borne and parasitic diseases (VBPD) have a major impact on the production of livestock, such as cattle, swine, goats and sheep, as well as crops, such as wheat, corn, and sorghum. The purpose of this review is to educate agricultural professionals in the state of KS about VBPD of current or potential concern and to inform the public about the challenges faced by the agricultural community. Methods: This review describes and discusses the endemic VBPD that currently impact agricultural production in KS and foreign VBPD of concern. In addition, we outline the major arthropod vectors of VBPD in KS, including ticks, mites, and various insects. In the context of this review, parasites are strictly limited to arthropod ectoparasites that negatively impact livestock production. Modern agricultural data for the state of KS were mostly sourced from the USDA National Agricultural Statistics Service, and current KS VBPD data were mostly sourced from the KS State Veterinary Diagnostic Laboratory. Conclusion: These VBPD have a large economic impact on the state and country, and we have concluded there is a need for updated estimates regarding the economic burden of VBPD in KS and throughout the United States to make better animal and crop health investment decisions.

A Review of West Nile Virus as a Cause of Human Disease in Kansas

Background: In the United States, West Nile virus (WNV) was first identified in 1999 in New York City and in Kansas in 2002. How the virus was introduced remains uncertain, although several potential methods have been hypothesized. This review presents an overview of what has occurred with WNV since 1999 and the potential for establishment of related viruses, such as Japanese encephalitis virus, if they were to be introduced in the United States. Materials and Methods: We have compiled human West Nile case data from Kansas over time with the purpose of illustrating how this virus has become endemic in the center of North America in a representative Midwestern state that is seasonal and does not have year-round mosquito vector activity. Case data were compiled from multiple sources including the U.S. Center for Disease Control and Prevention, the U.S. Department of Agriculture, and the Kansas Department of Health and Environment. Results: The annual reported numbers of human WNV infections have fluctuated widely in Kansas since the introduction in 2002. Between 2002 and 2022, there were a total of 715 reported cases in Kansas, with an average of 34 cases per year. Among the 715 cases, 73% were from 23 counties, but 4 counties accounted for 32% of this total with clusters of cases. Sedgwick County, which is the second most populous county in Kansas, represented 15% of the 715 total cases. Conclusion: The reasons for fluctuations in the number of cases reported each year and the distribution of these cases is uncertain, but they are most likely due to changes in the mosquito vector populations, which are influenced by environmental factors, such as seasonal rainfall, temperature, and humidity. With regards to the future, WNV is here to stay with annual fluctuations that are difficult to predict. The establishment of WNV in the U.S. and Kansas should serve as a warning for the possibility of establishment of other mosquito-vectored diseases, including Japanese Encephalitis virus.

The Perpetual Vector Mosquito Threat and Its Eco-Friendly Nemeses

Mosquitoes are the most notorious arthropod vectors of viral and parasitic diseases for which approximately half the world's population, ~4,000,000,000, is at risk. Integrated pest management programs (IPMPs) have achieved some success in mitigating the regional transmission and persistence of these diseases. However, as many vector-borne diseases remain pervasive, it is obvious that IPMP successes have not been absolute in eradicating the threat imposed by mosquitoes. Moreover, the expanding mosquito geographic ranges caused by factors related to climate change and globalization (travel, trade, and migration), and the evolution of resistance to synthetic pesticides, present ongoing challenges to reducing or eliminating the local and global burden of these diseases, especially in economically and medically disadvantaged societies. Abatement strategies include the control of vector populations with synthetic pesticides and eco-friendly technologies. These "green" technologies include SIT, IIT, RIDL, CRISPR/Cas9 gene drive, and biological control that specifically targets the aquatic larval stages of mosquitoes. Regarding the latter, the most effective continues to be the widespread use of Lysinibacillus sphaericus (Ls) and Bacillus thuringiensis subsp. israelensis (Bti). Here, we present a review of the health issues elicited by vector mosquitoes, control strategies, and lastly, focus on the biology of Ls and Bti, with an emphasis on the latter, to which no resistance has been observed in the field.