There have been recent reports of the mink farm related outbreak in Denmark which has received attention in the media, and has concerned many scientists, and health organisations. What's happening in Denmark now is important. Here's why. Thread.
There have been reports of transmission related to mink farming across several countries over the past few months. The recent outbreak in Denmark suggests that a mutated strain of virus passed from minks to humans, and then spread across humans.
Mutations in SARS-CoV-2 occur regularly, and most have minimal or no impact on viral fitness, as far as we can see from the data. But animal reservoirs can be more important in this regard. Mutations in a virus occur randomly through natural processes.
When mutations confer a selection advantage to the virus, these strains predominate and are transmitted. This is important because the selection pressure in different species can be different, which can lead to viruses diverging substantially in animal reservoirs.
This means that viruses that are then transmitted back from animal reservoirs can be quite different from the predominant circulating strains in human populations. This is concerning because some mutations may help the virus 'escape' the immune response.
This phenomenon has been observed for several infectious diseases with animal reservoirs, and we see a different form of this (genetic shift and genetic drift) with the flu. These sorts of changes can influence vaccine efficacy if a different strain is used for vaccination
We don't yet know the implications of the genetic changes in the Denmark strain. Early reports from the WHO suggest that these may be less susceptible to neutralising antibodies, but this needs a lot more assessment.
Scientists and public health officials who find this concerning are not being sensationalist. It's true we don't know whether the implications of this particular strain or outbreak are serious. But the wider implications are very concerning.
We know that SARS-CoV-2 likely spread to humans from an animal reservoir. Movement between animal and human reservoirs is concerning because it indicates that new genetically divergent strains can be introduced into the population in the future.
Irrespective of this particular outbreak, it's the possibility of future outbreaks which introduce different strains back into the human population that's worrying from the perspective of vaccination, and potentially pathogenicity.
Worrying about this and acting in response to this is prudent and cautious, not an overreaction. In the face of uncertainty, we have no choice but to act immediately to contain the outbreak given its *potential* implications. This is in line with the precautionary principle.
It also means that we need to look carefully at farming practices, and transmission in this context, as this represents a threat in the future. It also highlights the need for far more surveillance among farms, and animals that we know can transmit to humans.
I think the reporting of this has been cautious, and balanced. Its right to be concerned about this. With these events, we need to really think ahead, and understand wider implications, rather than those just related to specific events.
To me, this also makes a clear argument for focusing on elimination. The more transmission there is in communities, the more likely these cross-over events will occur, and the higher probability that one of these events will be significant.
It's prudent to be concerned, and respond now, whilst there is uncertainty. This shouldn't be labelled as sensationalist or panicky.
It's important we take a long-term view on this, rather than just the implications of this specific incident.
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A few thoughts on these interpretations, that appear to suggest (with caveats) that schools in England haven't necessarily contributed much to transmission. The evidence presented here does not necessarily support this. A thread.
The lower number of cases identified among 0-10 yr olds ignores the fact that we know that children are likely to be asymptomatic and mildly symptomatic, which means that symptom-based testing is likely to vastly underestimate infections in this age group
There have been significant clusters of infection of COVID-19 identified in schools (both primary and secondary). These form the majority of clusters of acute respiratory incidents identified related to COVID-19 since September.
A thread on where we are with the COVID-19 pandemic in England, and what we need to do urgently based on current evidence. This thread also explores why the govt Tier 1-3 strategy is nothing but a distraction from the actual public health response needed. 1/N
As we know, the PHE data shows an exponential increase in daily confirmed cases of COVID-19. We are currently seeing between 25-30K daily cases. This is likely an underestimate as testing capacity has been reached. Moreover, increases are occurring across all of England. 2/N
Predictably increase in case numbers have translated over time into increasing hospitalisations across all of England, with regions in the North likely to hit NHS capacity soon if we don't act. While increases in the South appear slower, these are only lagging 3-4 wks behind. 3/N
tw: misogyny, discrimination, harassment in academia
A thread about my observations from academic and other contexts. I've felt compelled to write this after realising how the deliberate framing of these issues prevents any change in the status quo, and perpetuates injustice.
As women, many of us face misogyny in our workplaces, and in society on a daily basis. Here, misogyny is defined not as hatred of women, but rather structural patriarchal norms that have certain expectations from women & penalise those who break these, or speak out against these.
Of course, discrimination is intersectional, with ethnic minority women likely to fare worse in these systems. Much like with racism, experiences of women are often shaped by daily micro-aggressions - including a dismissal of their expertise, their discomfort, and their feelings.
Another declaration on 'herd immunity' signed by Sunetra Gupta(Oxford), Jay Bhattacharya (Stanford) & Martin Kulldorff(Harvard) who don't have a single peer reviewed publication on covid-19 epidemiology between them
And these are not experts, or researchers who have provided any evidence to support their damaging views. If you want experts, there are so many around - who are basing their views on the actual evidence. There is zero evidence to support a 'herd immunity' based strategy.
@iansample - while I appreciate comments from actual experts like @trishgreenhalgh and @BillHanage are included, the way the piece is set seems to suggest these are equally valid opinions from equals in a field. This couldn't be further from the truth.
Given the recent public statements by several govt advisors regarding opening of schools, here's a thread on evidence around COVID in children:
The govt (& UK scientific 'experts') have recently cited findings from the recent PHE study as suggesting school openings are safe 1/N
The study does not in fact show this at all. It essentially collates data on results from test & trace during the period when schools were opened in June - when only ~7% of students attended. There are several key limitations of this work:
1. Given the attendance was a fraction of normal attendance, we cannot possibly extrapolate what this will mean for when schools fully open from this study. 3/N
This is exactly the problem. Not only is pillar 2 data not available publicly, it's also not available to local authorities, making it impossible to identify what's causing this outbreak, or even where it is spatially. 1/N
Outsourcing testing to private companies has meant that surveillance data aren't joined up centrally. This means that: 1. There's a significant delay in identifying outbreaks- as we saw in Leicester 2. When these are identified, we have no idea of where clusters of infection are
We're essentially trying to put out localised fires we can't see by using general lockdown measures. The whole point of test, trace and isolate was to be able to identify local outbreaks and take focused measures to contain them.