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Feb 13Liked by Peter Halligan

These thoughts on wolbachia and canine heartworm disease. Wolbachia bacteria require the host heartworm to survive and the heartworm requires Wolbachia for its survival. Eliminating Wolbachia through the use of doxycycline is important to the treatment of the heartworm-infected animal.

What Are Wolbachia and Why Are They Important to the Heartworm?

Wolbachia bacteria are related to Rickettsia, which are intracellular bacterial parasites that live within certain invertebrates, including some flies and nematodes.3 Wolbachia are bacterial symbionts. As endosymbionts, Wolbachia bacteria require the host organism, the heartworm, to survive; equally, the heartworm requires Wolbachia for its survival.

The exact function of Wolbachia in heartworms is unknown. It has been hypothesized that the presence of these bacteria may aid in energy metabolism. Populations of Wolbachia, which are present in all heartworm life stages, expand between the third-stage infectious larvae (L3) and fourth-stage larvae (L4). For this reason, it is hypothesized that preventing the expansion of the Wolbachia population will prevent heartworm development.

Wolbachia possess surface proteins (WSPs)8 that are responsible in part for the pathogenesis of heartworm disease. When adult heartworms die naturally or as a result of melarsomine administration, the bacteria and their components, including WSPs, are released. The WSPs recruit neutrophils and other immune cells; as these cells are recruited on the microscopic level in the blood vessels, partial blockage of vessels can result, which can impede blood flow. Furthermore, inflammation of the dog’s lungs can manifest in clinical signs, such as coughing and dyspnea.

Although we do not understand the complete role of Wolbachia in the pathogenesis of heartworm disease, experimental and clinical trials have shown that elimination of the bacteria using doxycycline decreases both macroscopic and microscopic pathology, as well as clinical signs.

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Interesting.

Doxycycline mentioned here along with Avermectin-B1

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8163879/

Makes you wonder if Dengue in humans is a kind of heartworm version and whether there is an equivalent amongst the livestock in the human food chain - or amongst animals/birds/reptiles in the wild.

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Interesting...

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8163879/

doxycycline mentioned.

Makes you wonder if dengue is some sort of human equivalent of heartworm in dogs (and cats) and whether there is another equivalent in the human food chain amongst livestock/chickens or in the natural habitat...

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Feb 13Liked by Peter Halligan

What - an Ivermectin for mosqueitos? Don’t like the target age range 10-14 but that’s maybe a hangover because of the c-19 devastation already visited upon the West’s children. Domestic production by the communist Brazilian fake government though: that is downright worrying. God knows what they’ll add to that.

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