by
Robert Gorter, MD, PhD, etc.
June 28th, 2024
This deer visibly shows signs of chronic wasting disease.
Terry Kreeger, Wyoming Game and Fish and Chronic Wasting Disease Alliance.
I know from personal contacts with several scientists currently looking into prion diseases being spread through vectors like Mosquitos and ticks. I read an article a year or two ago addressing chronic wasting disease (CWD) in deer and looking at whether prions could be transferred through various vectors.
I really would not be shocked if prions can be spread by these means as CWD has become epidemic in deer, elk and reindeer whether the herds were kept quarantined from wild populations or not.
Prions are about one of the most stable structures. They can withstand boiling, autoclaving, more than 2% SDS and other detergents, most known proteases, etc. In fact, the most effective agent able to degrade prions (or amyloids) is a yeast protein Hsp104.
Reported cases of chronic wasting disease in North America, as of 2023. Since 2020, there is a significant increase in the number of reported cases in both wild animal populations and in captured ones.
Chronic wasting disease (CWD), sometimes called zombie deer disease, is a transmissible spongiform encephalopathy (TSE) affecting deer. TSEs are a family of diseases thought to be caused by misfolded proteins called prions and include similar diseases such as BSE (mad cow disease) in cattle, Creutzfeldt–Jakob Disease (CJD) in humans and scrapie in sheep. Natural infection causing CWD affects members of the deer family. In the United States, CWD affects mule deer, white-tailed deer, red deer, sika deer, elk, caribou, and moose.[3] The transmission of CWD to other species such as squirrel monkeys and humanized mice has been observed in experimental settings.
In 1967, CWD was first identified in mule deer at a government research facility in northern Colorado, United States. It was initially recognized as a clinical “wasting” syndrome” and then in 1978, it was identified more specifically as a TSE disease. Since then, CWD has been found in free-ranging and captive animal populations in 30 US states and four Canadian provinces. In addition, CWD has been found in one Minnesota red deer farm, one wild reindeer herd in Norway (March 2016) as well as in wild moose. Single cases of CWD in moose have been found in Finland (March 2018) and in Sweden (March and May 2019, September 2020). CWD was found in South Korea in some deer imported from Canada.[6] CWD is typified by chronic weight loss and clinical signs compatible with brain lesions, aggravated over time, always leading to death.
Mosquito bites are small, raised bumps on the skin that come from a female mosquito feeding on human blood. Mosquitoes are small, flying insects known as vectors (living things that carry diseases between animals and humans). Vectors often carry infections through blood.
Why do Mosquitoes bite?
Mosquitoes bite and suck blood for reproduction. Though male mosquitoes only eat flower nectar, female mosquitoes eat both flower nectar and blood. The females need the protein in blood to develop eggs.
What happens when a Mosquito bites you?
Mosquitos have a long mouthpart (proboscis) that extends far beyond their heads. It looks like a tiny needle. When a mosquito bites you, it uses this mouthpart to pierce your skin, suck your blood and secrete saliva into your bloodstream.
Why do Mosquito bites itch?
When a mosquito secretes saliva into your bloodstream, your body registers the saliva as an allergen. Your immune system then sends the chemical histamine to the area where the mosquito bit you to remove the allergen from your body. Histamine is what causes your mosquito bites to itch and swell. Most people have a mosquito bite allergy.
How do Mosquitoes spread disease?
The mosquito bites; then first injects through its extremely thin sucking tube its own saliva which contains enzymes to prevent the blood from clotting. The significant reaction by the bitten animal or human is towards these enzymes which the mosquito injects to prevent blood clotting
Mosquitoes spread disease through their bites. Mosquitoes are vectors (living things that carry diseases between animals and humans). Vectors often carry infections through blood. Many of the creatures classified as vectors are bloodsuckers. Other vectors include ticks, fleas and sandflies.
When a mosquito bites, it not only sucks blood but first secretes / injects its saliva to prevent blood clotting in its minute sucking tube. This saliva enters your blood. There is an exchange of fluids between the mosquito and your bloodstream. An infected mosquito has fed off a person or animal with the disease. It then passes the infection on when it bites again. Mosquitoes often feed in a method called sip feeding. Sip feeding means that the mosquito doesn’t just suck all of the blood it needs from one source — it takes multiple meals from multiple sources. Unfortunately, this exposes more people to infection.
Although reports in the popular press have been made of humans being affected by CWD, by 2004 a study for the Centers for Disease Control and Prevention (CDC) suggested, “More epidemiologic and laboratory studies are needed to monitor the possibility of such transmissions”. A 2019 study concluded that “the potential exists for transmission to humans and subsequent human disease”. The epidemiological study further concluded, ” as a precaution, hunters should avoid eating deer and elk tissues known to harbor the CWD agent (e.g., brain, spinal cord, eyes, spleen, tonsils, lymph nodes) from areas where CWD has been identified”. In April 2024, it was revealed that two men from the same hunting group contracted CJD, prompting medical researchers to speculate transmission had occurred from consuming CWD-positive venison.
History
In February 2003, the CDC published a report of “Fatal degenerative neurologic illnesses in men who participated in wild game feasts–Wisconsin, 2002”. It read in conclusion that “Although no association between CWD and CJD was found, continued surveillance of both diseases remains important to assess the possible risk for CWD transmission to humans.” In September 2003, Hoey pointed out that one of the three patients (the 55 year-old) “presented with a 3-month history of difficulty in writing and unsteadiness of gait, followed by dementia, speech abnormalities and myoclonic jerking. Pathologic examination of the brain at autopsy 3 months later revealed widespread subcortical spongiform lesions consistent with CJD.”
As of 2013 Patrice Klein the CWD Program Manager at USDA/APHIS rejected the somewhat inconclusive findings of Hoey and stated that no evidence had been found of transmission to humans from deer, nor by eating animals in the deer family, but both channels remain a subject of public health surveillance and research.
References
“CWD in Animals”. CDC. 10 January 2024. Retrieved 27 December 2023.
“Chronic Wasting Disease (CWD)”. USDA. APHIS. 2 June 2020. Retrieved 27 December 2023.
Patrice N Klein, CWD Program Manager USDA/APHIS (5–6 February 2013). Chronic Wasting Disease – Review of Disease Transmission and Control (PDF). WHHCC Meeting. Archived from the original (PDF) on 26 September 2014.
“Transmission | Chronic Wasting Disease (CWD) | Prion Disease | CDC”. www.cdc.gov. 3 December 2018. Retrieved 21 February 2019.
“Distribution of Chronic Wasting Disease in North America”. USGS.gov. 1 April 2022. Retrieved 29 August 2022.
“Occurrence | Chronic Wasting Disease (CWD) | Prion Disease | CDC”. www.cdc.gov. 25 February 2019. Retrieved 5 March 2019.
Belay ED, Maddox RA, Williams ES, Miller MW, Gambetti P, Schonberger LB (June 2004). “Chronic Wasting Disease and Potential Transmission to Humans”. Emerging Infectious Diseases. 10 (6): 977–984. doi:10.3201/eid1006.031082. PMC 3323184. PMID 15207045.