Parasites impact the health of companion and production animals, wildlife and humans. The Verocai Lab is performing research in various fronts to address diagnostic needs in veterinary parasitology, and also better understand parasite threats to companion and production animals, wildlife, and those which can also infect humans.


Heartworm is a devastating disease of dogs, cats, and ferrets caused by Dirofilaria immitis, a filarial worm that is transmitted by mosquitoes. Heartworm is with no doubt the most important parasite of dogs in the United States. Despite efforts of veterinarians and owners in keeping animals under appropriate prevention year-round, there is strong evidence that more dogs are getting infected in various areas of the country. Resistance of heartworm to the drugs we use as preventives is also an emerging issue.

Several of our projects focus on advancing how we diagnose heartworm infection in dogs, which is often when the disease is advance. We are looking into parasite-derived markers that may be able to detect infection much earlier, and before clinical disease appears, and before the dogs can serve as reservoir for the infection of mosquito vectors.

We are also looking into better ways to diagnose heartworm infections in a more advanced stage, where the microfilariae can be found circulating in the blood. We are testing and validating new technologies such the DiroScope, a smart-phone base microscopy test for detecting microfilariae in blood in as short as 2 minutes. We are further testing the device for qualitative and quantitative test, and also as means for determining the potential field resistance cases.

Parasite Biodiversity

Parasites are neglected part of the world’s biodiversity. However, understanding the diversity of vector-borne and zoonotic parasites, which animal hosts they affect, which insect vectors they may use, and where they occur are extremely important …

The genus Onchocerca is comprised by numerous species [Link Lefoulon], some of them of public health relevance like Onchocerca volvulus, causative agent of Human Onchocercosis or River blindness, a Neglected Tropical Disease by the WHO [Link], and others infecting domestic animals and wildlife, with potential impact on their health and wellbeing.

Our main effort in this area is to understand the biodiversity of the genus Onchocerca in North America, their vector, host and geographic associations. Our recent studies show that there are potential uncharacterized species infecting ungulates across North America, as opposed to the existence of a single species infecting various host species. This includes Onchocerca species infecting white-tailed deer, mule deer, moose, elk, caribou, pronghorn, among others. We would like to characterize parasite specimens, and screen samples of vectors and host samples across the continent to fill these knowledge gaps. Ultimately, having a strong baseline for diversity, and host and geographic associations of Onchocerca species will assist us in understanding their impact on the health of various game species in a rapidly changing world.

Bison Parasites

Bison producers are among our most loyal clients at the Parasitology Diagnostic Laboratory. Bison in the Southern Plains face numerous parasite-related issues that impact the health of individual animals and, sometimes, of an entire herd. We have been providing diagnostic service to various producers and the Texas Bison COI [Link] that directly impact treatment and management decisions. There is a need to better understanding the health impacts of these parasites, and economic impact on producers by building a strong baseline on parasites across farmed and wild bison herds, assess for anthelmintic resistance, and current management strategies.