Read on Twitter
THREAD 14: #SARSCOV2 and Human Herpesviruses
1/ Given the news yesterday about SARSCoV2 being found in the human brain, and my background in women’s health and sexual health, I’ve been ruminating on human herpesviruses (HHV) and SARSCoV2 #COVIDー19
https://twitter.com/ErinSandersNP/status/1260202782931464192?s=20 https://twitter.com/ErinSandersNP/status/1254789057088851970
1/ Given the news yesterday about SARSCoV2 being found in the human brain, and my background in women’s health and sexual health, I’ve been ruminating on human herpesviruses (HHV) and SARSCoV2 #COVIDー19
https://twitter.com/ErinSandersNP/status/1260202782931464192?s=20 https://twitter.com/ErinSandersNP/status/1254789057088851970
2/ There are over 100 known herpesviruses. In humans, the most well known are: herpes simplex virus type 1 and 2 (HSV1, HSV2) which cause oral “cold sores” and genital lesions, varicella-zoster virus (VZV) commonly known as “chickenpox” (primary) or “shingles” (reactivation)...
3/ ...and Epstein-Barr virus (EPV), commonly known as infectious mononucleosis or “mono.” https://www.ncbi.nlm.nih.gov/books/NBK8157/
4/ However, there are actually 8 types of herpesvirus that only infect humans, including: HSV-1, HSV-2, VZV, EBV, cytomegalovirus (CMV), human herpesvirus 6 variants A and B (HHV-6), human herpesvirus 7 (HHV-7), and Kaposi's sarcoma virus/human herpesvirus 8 (HHV-8).
5/ Another #virus, called B virus, is present in rhesus monkeys and can be transmitted to humans via a bite from an infected animal. It causes an encephalitis that is usually fatal and survivors have brain damage. https://www.ncbi.nlm.nih.gov/books/NBK8157/
6/ Similar to #SARSCoV2, there are wide spectrums/ severity of disease presentations with each of these viruses from clinically asymptomatic to producing life threatening disease. A unique characteristic of herpesviruses is their ability to establish latent infections in tissues
7/ For example, after intial infection, HSV lives in the nerve cells for the remainder of the host’s life. It can also go in and out of hiding/reactivation throughout the lifespan.
8/ From an evolutionary perspective, this dormancy or latency allows the virus to ensure continued spread to more hosts over time, and yet continue to evade the human immune system. https://www.sciencedaily.com/releases/2018/03/180315093824.htm
9/ At any time, latent virus may be reactivated and start to replicate. Latent virus reactivation is a well-recognized biologic phenomenon but not well understood.
10/ Stimuli that have been observed to be associated with the reactivation of latent HSV have included stress, menstruation, and exposure to UV light.
11/ Also interestingly, replication for all herpesviruses is considered “inefficient,” with a high ratio of non-infectious to infectious viral particles.
https://www.ncbi.nlm.nih.gov/books/NBK8157/
This is interesting to consider, due to the prolonged viral shedding/detection of #SARSCoV2 via PCR
https://www.ncbi.nlm.nih.gov/books/NBK8157/
This is interesting to consider, due to the prolonged viral shedding/detection of #SARSCoV2 via PCR
12/ Despite the stigma associated with it, HSV is incredibly common. In the #USA from 2015–2016, prevalence of HSV-1 was 47.8% and HSV-2 was 11.9%.
https://www.cdc.gov/nchs/products/databriefs/db304.htm
https://www.cdc.gov/nchs/products/databriefs/db304.htm
13/ With regard to HSV and EPV, many people are carriers and have no idea they carry the #virus. For example, in the #USA, an estimated 87.4% of 14 to 49 year olds infected with HSV-2 have never received a clinical diagnosis.
https://www.cdc.gov/std/herpes/stdfact-herpes-detailed.htm
https://www.cdc.gov/std/herpes/stdfact-herpes-detailed.htm
14/ Most HHV infections are spread via direct physical contact with an infected host or their bodily fluids. However, VZV is transmitted through respiratory droplets (like #SARSCoV2) and is highly contagious with about 95% of adults showing serologic evidence of prior infection.
15/ Additionally, by the age of 5, antibodies are present in virtually 100% of the population to both of HHV-6 and HHV-7. https://www.ncbi.nlm.nih.gov/books/NBK8157/
16/ Viruses are cellular parasites.
They cannot survive without infecting a host.
To kill the virus inside the cell, you must kill the cell.
@AMannanBaig
They cannot survive without infecting a host.
To kill the virus inside the cell, you must kill the cell.
@AMannanBaig
17/ Regardless of latency, one of the challenges of treating a herpes infection is that the cells in which it resides are neurons or nerve cells. Destruction of these cells would damage the nervous system.
#SARSCoV2 can invade the neurons.
@VirusesImmunity @florian_krammer
#SARSCoV2 can invade the neurons.
@VirusesImmunity @florian_krammer
18/ HSV can actually cause encephalitis, characterized by hemorrhagic necrosis of the inferiomedial portion of the temporal lobe. Disease begins unilaterally, then spreads to the contralateral temporal lobe. It is the most common cause of focal, sporadic encephalitis in the #USA.
19/ Clinical manifestations of HSV encephalitis include headache, fever, altered consciousness, and abnormalities of speech and behavior. Focal seizures may also occur. https://www.ncbi.nlm.nih.gov/books/NBK8157/
20/ This route of infection concerns me due to the Michigan case of COVID-19–associated Acute Hemorrhagic Necrotizing Encephalopathy https://pubs.rsna.org/doi/10.1148/radiol.2020201187
and other reported cases of encephalopathy in CA, FL, Italy, Japan, and China.
and other reported cases of encephalopathy in CA, FL, Italy, Japan, and China.
21/ There is still so much we don't know or understand about #SARSCoV2 and #COVIDー19. But looking at history, looking at other viruses, and also other diseases may give us more clues about how to fight this novel pathogen and disease. @tmprowell @EricTopol @PeterHotez
22/ And now you know more than you ever wanted to about Herpes :)
Shout out to my women's health colleagues on Twitter:
@jackie_parchem @janevandis @DrSueGross @MamaDoctorJones @doctorjenn @DrJenGunter @jimgthornton @jfitzgeraldMD @dramypark
Shout out to my women's health colleagues on Twitter:
@jackie_parchem @janevandis @DrSueGross @MamaDoctorJones @doctorjenn @DrJenGunter @jimgthornton @jfitzgeraldMD @dramypark
@threadreaderapp please unroll
