Thanks Walter for all the COVID dots that you connect. It's hard to believe that you aren't a medical research professional. I actually once bought a kitten that had FIP. He had a swollen belly, like really swollen like it had a watermelon growing in there, after only 2 weeks of having him, I took him to the vet and they that is when I found out was FIP was. The vet put him to sleep right there and then. It was so sad, I never thought for a moment that I wouldn't come back home with him.

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I do some research (sometimes it's many topics at the same time) just for my own interest in everything. So, for my research, I needed to find the missing link which could connect snakes and SARS. My search stopped at Civet cats. Following ''civet cats'' I found some interesting papers. I thought maybe you want to see this cos you have been thinking about ''SARS-CoV-2 AND ITS RELATION TO FELINE INFECTIOUS PERITONITIS''

Quote: ''A personal journey through coronavirus evolution

The Sir Arnold Theiler Memorial Lecture

In Utrecht, it all started with a disease: Feline Infectious Peritonitis (FIP)

which is fatal in most (clinical) cases

its biology was poorly understood

prevention (still) is difficult

It is an enigmatic disease:

a sporadic fatal viral condition is a contradiction in terms

antibodies are of no benefit for the cat

they may even precipitate disease, causing the

'early death' phenomenon

Clinical signs

extended abdomen

undulating, unresponsive fever

anorexia, emaciation


ocular/neurologic symptoms, icterus

wet form: polyserositis with effusions

dry form: disseminated pyogranulomas

The discovery (1977): FIP is caused by a coronavirus''

(picture of 2 papers, found them)



Interesting that the second paper also is there but not accessible:



''The result of this discovery was threefold:

1.we started to work on feline viruses

2.we focused on coronaviruses

3.we became fascinated by viral evolution

“...nothing in biology makes sense except in the light of evolution...”

Theodosius Dobzhansky (1900-1975)

I should like to entertain you about coronavirus evolution as it leads to new* diseases

in individual animals: pathogenesis (FIP)

in the field: epidemiology (TGEV/PEDV;SARS; MERS)

*new in the sense: hitherto unknown to science

Why coronaviruses?

Because they are the largest enveloped, positive-stranded RNA viruses with the largest viral RNA known to science, and thus: the highest probability of making genetic mistakes (errors -mutations)

without a proof-reading mechanism to correct them.

Evolutionary “behaviour” of coronaviruses

Occupation of new ecological niches through change in tropism (deletions; point mutations;


TGEV – gut to lung

FIPV – enterocyte to macrophage

SARS-CoV: “species jumping” civet to human

MERV-CoV: “species jumping” bat to camel to human


Transmissible Gastroenteritis Virus (TGEV) of swine is found in feces of pigs ≤ 8 wk after recovery

but has been isolated from lungs > 3 mo p.i. - meaning virus persistence

1984: a “new” respiratory coronavirus was identified in pigs in Belgium, with ≈700nt deletions in the S gene, but conservation of neutralisation-relevant epitopes

The respiratory variant has displaced the enteropathogenic parent virus in all pig populations

thereby acting as a “natural vaccine”.


Peritonitis-causing feline coronaviruses are in vivo mutants occurring in individual, persistently infected cats e.g. when cell-mediated immunity is suppressed (such as under “crowding” stress, after FeLV- or FIV- infections) arise stochastically, under conditions that allow expansion of the so-called “quasispecies cloud''


Crucial for the FECV –FIPV transition:

The A at nucleotide 23531 was 100% conserved in all 183 FECVs in our collection.

Of the 118 FIPVs, 96 (81.4%) had a T and 12(10.2%) a C at this position; in both cases, this changes

the methionine (M) occurring at position 1058 in the FECV S protein into a leucine (L) in FIPV (i.e.,

mutation M1058L).


Viruses have crossed the host species barrier

time and again,

and will forever...


Interspecies transmission

severe acute respiratory syndrome(SARS): palm civet – to man

middle East respiratory syndrome (MERS): African bats, camelids –to man

bat coronavirus: Leschenault's rousettes (Rousettus leschenaulti, fruit bats Megachiroptera) - to

Pomona leaf-nosed bats (Hipposideros pomona, insectivorous, Microchiroptera)

SARS – the first human ‘killer’ coronavirus'' Quote ends.

And a picture from CDC

''Notice of embargo of civets. Embargo is effective on January 13, 2004 and will remain in effect until further notice''

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