Researchers at the Connecticut Veterinary Medical Diagnostic Laboratory (CVMDL) located at the UConns College of Agriculture, Health and Natural Resources have identified the genetic makeup of West Nile virus strains found in an alpaca and a crow.
These results have been published in Frontiers in Veterinary Science.
In 2021, eight West Nile virus cases were referred to the CVMDL for diagnosis of seven birds, both domestic and wild, and one alpaca.
We decided to pursue some avenues of research through these diagnostic cases because we had an interesting cohort of West Nile cases that had emerged that fall, says Natalie Tocco 23 (CAHNR), anatomical pathology resident in the Department of Pathobiology and Veterinary Science. .
Of the eight cases, the Massachusetts alpaca and a Connecticut crow had the highest amount of virus in their systems at the time of diagnosis.
Focusing on these two cases, the researchers were interested in seeing if there were any genetic differences between the viruses because they occurred in different species in different states.
After sequencing the complete genomes of the viruses, the researchers compared them with existing data. They found that West Nile virus in the crow was similar to the virus identified in a mosquito and birds in New York between 2007 and 2013. The virus found in the alpaca resembled West Nile viruses found in mosquitoes in New York, Texas and Arizona between 2012 and 2016.
[These findings] they show the variety of strains that are circulating that can really alter what we see in populations of what mosquitoes drag into different areas, Tocco says.
This information can help scientists predict where different strains of the virus might appear when you consider how mosquitoes and birds move around the country.
The researchers concluded that differences in the genetic makeup of these viruses suggest that vector-host feeding preferences are likely driving viral transmission. Different species of mosquitoes prefer to feed on different animal hosts. This leads to different types of animals getting infected with West Nile viruses.
Understanding the genetic makeup of viruses could allow researchers, diagnosticians and veterinarians to understand which animals may be more susceptible to the virus, the severity of the disease and what the symptoms might be.
It could open a whole can of worms, Tocco says. Actually, I think we need to do more research on this to see what we’re finding and what kinds of patterns we should expect in terms of different strains and what kinds of diseases we see with those.
West Nile virus was first detected in New York City in 1999 and has spread rapidly throughout the country. In 2000 it was present in Connecticut. Since then, West Nile has remained a public health problem in the United States
In the early 2000s, the CVMDL published one of the first papers on West Nile virus in the United States
In addition to having it here in Connecticut and being a public health concern, it also brings more variety to the lab to bring West Nile research back to the fore through the use of our diagnostic cases, says Tocco.
While this paper focuses on just two cases, the researchers are currently working on another paper that looks at specific symptoms in all eight cases.
The number of West Nile virus cases that CVMDL sees each year varies. During particularly humid summers, which are ideal for mosquitoes, they tend to see more cases. In 2022 they diagnosed 30 cases.
Birds and corvids such as crows, crows and jays in particular are common carriers of West Nile virus.
The most common West Nile symptoms in these animals include seizures, inability to stand, neurological signs, and ocular signs. Symptoms affecting the eyes are particularly common in birds of prey such as eagles, owls and hawks. Raptors can also get heart disease from the virus.
There’s a variety of lesions that we can see with West Nile, so it’s more about being proactive with these diagnostic cases at certain times of the year and staying alert because it’s not just about the nervous system signs in some animals, says Touch.
The most common season for West Nile viruses is from August to October. However, as the climate in Connecticut warms, the West Nile range is expanding. Tocco says he diagnosed cases of West Nile as late as November and as early as May.
Those could be the anomalies, but they could be a predictor of what we can expect in the future, Tocco says. And to not put blinders on the time of year, but to expand that window based on what we were seeing diagnostically.
This work refers to the strategic vision area of the CAHNR that is focused Improve health and well-being locally, nationally and globally.
Follow UConn CAHNR on social media
#UConn #researchers #identify #genetic #makeup #West #Nile #strains #UConn #Today