Thread: A major barrier to progress in understanding the neurologic manifestations of #LymeDisease has been a lack of a tractable laboratory animal model to evaluate the mechanisms of central nervous system pathogenesis.
For decades we have seen study after study of Lyme arthritis. As it turns out the most frequently reported Lyme symptoms are neurological symptoms: memory loss and cognitive impairment, sleep impairment, psychiatric manifestations, headaches, neuropathy and more. 2/
This is the first study, to my knowledge, that shows how Borrelia burgdorferi gets into the central nervous system, how the immune system responds, and how the bacteria adapt to the immune system. #Lyme
Meet the researcher Catherine Brissette, Ph.D. globallymealliance.org/meet-researche…
So what the researchers show is that 1) B.b colonize the dura matter (a collagenous protective layer around the brain) within 7 days after infection, and 2) the location of the bite (eg the closer to the brain) effects the level of infection in the dura matter. #LymeDisease
3) The authors "did not find evidence of differences in CNS colonization between Borrelia species or intraspecies isolates in our model."
4) B.b. "burdens in the dura mater peaked at day 7 post-infection, and by days 14–28 were quickly reduced to low levels similar to that reported during late disseminated infection."
5) "Intriguingly, this early peak and clearance of spirochetes more closely resembles that reported in blood, rather than other peripheral tissues where burdens peak between 2–3 weeks post-infection and remain relatively higher throughout infection." #Lyme
6) "This rapid reduction of spirochete numbers in the dura mater suggests immune pressures similar to those seen in the blood, and was at least in part due to an adaptive immune response." #LymeDisease
7) "Nonetheless, the ability of B. burgdorferi to persist at low levels in this tissue for at least 75 days post-infection compared to undetectable levels in the blood during persistent infection may be due to bacterial interactions with these host proteins." #Lyme
While the researchers did not find cultivable B.b spirochetes w/in the brain they did map an increased inflammatory cytokine response, a transient IFN response was demonstrated that was not dependent on T cells or B cells.
The dura mater possesses: "blood vessels, lymphatic drainage, and a high density of resident immune cells including dendritic cells (DC), mast cells (MC), innate lymphocytes (ILCs), meningeal macrophages, T cells, and B cells capable of supporting a robust immune response"
In conclusion "Although the potential pathologic consequences of the observed changes in the brain parenchyma are not clear in our model, our findings demonstrate that the brain is not simply a naïve bystander during B. burgdorferi infection of laboratory mice." 👏👏👏
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In an encouraging development yesterday @CDC_NCEZID representative Ben Beard made an important announcement--a new "national strategy" for vector-borne diseases. I'll explain in a thread 1/n lymedisease.org/framework-vect… via @Lymenews
The Kay Hagan Tick Act, passed in 2019, called for @hhs to develop a national strategy to address issues related to vector-borne diseases. The Lyme community fought hard for the passage of the #TICKactlymedisease.org/tick-act-appro… via @Lymenews 2/
The geothermal features in Yellowstone are amongst my top 10 favorite sites on this planet. Here’s a bit of #microbio history on the PCR test I’d like to share.
Pictured: Grand Prismatic at the Midway Geyser Basin @YellowstoneNPS
“Until the 1980s, our ability to study DNA was limited. Things we take for granted today such as DNA fingerprinting to identify criminals, DNA medical diagnoses, DNA-based studies of nature, and genetic engineering did not exist.”
“But in 1985, the polymerase chain reaction (PCR) was invented. PCR is an artificial way to do something that living things do every day—replicate DNA. PCR is the rocket ship of replication, because it allows scientists to make billions of copies of a piece of DNA in a few hours.
Thread. @Sermo survey of 6,227 physicians worldwide: 85% of US physicians report #COVID19 testing takes 2-5 days or longer, while nearly half of international physicians report testing is completed within just 24 hours.
Survey @Sermo says, 91% of US physicians and 83% of international physicians say the status of #COVID19 testing is far below what is needed.
Survey @Sermo says "Physicians most request life science firms develop new rapid tests for COVID-19, followed by new drugs that offer immunity to front-line workers and accelerate efforts to test existing drugs to treat #COVID19"
The WHO described the #symptoms of 55,924 laboratory confirmed cases of #COVID19 in China in the period up to February 20.
The visualization here shows this data.
This visualization shows the severity of symptoms suffered by 44,415 Chinese patients confirmed to have coronavirus in the early period up to February 11. #COVID19#symptoms
Another eye opening read: "Rickettsiosis Subcommittee Report to the TBDWG" hhs.gov/ash/advisory-c…
Six common tick species are now involved in the transmission of Rocky Mountain spotted fever and/or other agents of the spotted fever group Rickettsiae in the United States (R. rickettsii, R. parkeri, R. massiliae, and R. 364D are proven human pathogens)
Gah! 72% of Rhipicephalus sanguineus ticks (brown dog ticks) in California found to carry Rickettsia massiliae. (Beeler et al., 2011) I mean, seriously, what doctors are even aware of this let alone testing for it? ncbi.nlm.nih.gov/pmc/articles/P…