Thread by @angie_rasmussen

There are critical outstanding questions about the MO bird flu case that need to be addressed now (and why reporting delays are unacceptable). They concern its pandemic potential.

Where did this virus come from?
How was the infection acquired?
Is human transmission occurring?

https://twitter.com/angie_rasmussen/status/1832304383641497876

Where did the virus come from?

Viruses don’t materialize out of thin air. They only come from infected hosts, so we need to think about how the patient could be exposed to said hosts. No contact with animals reported, but indirect contact or exposure could still occur.

This is also is why we need sequence data immediately.

Is this high or low path avian influenza?
Is this a reassortant? (Reassortment allows flu to take rapid evolutionary leaps ahead & cross species barriers)
Has the virus acquired mutations associated with human adaptation?

How was the infection acquired & from what host?

Birds, cows, pigs, rodents, other animals:
Shit/manure
Eggs
Raw milk
Handling or eating meat or carcasses
Unreported direct contact with stray or pet dogs/cats/birds

Humans:
Inhaled aerosols
Contact with body fluids
Fomites

Is human transmission occurring?

If the answer is yes, that’s very bad. One of the reasons H5N1 is considered low risk to the general public is that it doesn’t transmit efficiently between humans. If this infection was acquired from a human, that risk profile changes.

Also, if this infection was acquired from a human, that means undetected community spread is occurring and transmission chains are already established. The more complex these transmission chains are, the harder it is to contain using standard epi approaches.

I vividly remember my visceral gut punch reaction to reading this thread. I was in a car on my way to 30 Rock to an interview with @AliVelshi. I told the producers on arrival that this changed everything. This wasn’t an outbreak that could be contained. This was a pandemic.

https://twitter.com/trvrb/status/1233970271318503426

In particular, this tweet was what made me realize that simply put, we were fucked. Undetected community transmission for weeks was beyond fixing with an epi investigation and isolation/quarantine.

https://twitter.com/trvrb/status/1233970559257468928

And the reason it was undetected was due to the CDC’s inexcusable failure to rapidly develop a functional diagnostic test and enable clinicians, scientists, and local public health officials to implement testing themselves.

npr.org/2020/11/06/929…

These failures profoundly hindered identifying cases in a timely manner, which is what allowed cryptic community transmission to occur.
washingtonpost.com/investigations…

Oh and guess what? History is repeating with regard to testing for H5.

https://twitter.com/amymaxmen/status/1831122784157626372

It is absolutely imperative to investigate whether the H5Nx case in Missouri was the result of human to human transmission to accurately assess risk to the public. That risk is much, much higher if that is the case. It is astonishing that so little urgency is being conveyed.

This is justified by “we aren’t seeing a signal in existing flu surveillance systems”…but so what? There wasn’t a signal in Snohomish County, WA in Feb 2020 either…because there wasn’t testing to identify one.

If Trevor Bedford & colleagues hadn’t taken it upon themselves to do their own testing, sequencing, and surveillance, we might not have known until the hospitals started filling up with Covid patients. If that had happened, even more people would have died.

So we need to *rapidly* answer these questions about where the virus came from, how it was acquired, and whether human to human transmission is occurring.

Our COVID response didn’t exactly cover our public health systems in glory. Let’s not repeat these mistakes for avian flu.