OMICRON THE ONGOING EPIDEMIC
Omicron has arrived on the global scene so fast that none of the evidence we had for the original Covid-19 outbreak is present. In early 2020, figures about spread and mortality were available from a number of important papers, results from cruise ships etc. These pioneering results were regarded as inadequate at the time and people were reluctant to draw conclusions from them.
At the moment however, with virtually no evidence, some 'medical experts' have been making unscientific claims, and these have been echoed by some political figures.
In India, a top epidemiologist stated
"The consequence of a viral infection now is just like a cold. The infection is almost unstoppable and highly infectious, but a majority will not know they are infected.... Fewer will be hospitalised. It is not a frightening disease anymore."
In what appears to be a major outbreak of wishful thinking, 'experts' in Europe are claiming that "this is the beginning of the end of the pandemic" and "the virus is losing its power" . What is being called "an entirely different disease" is at the same time being declared an identical disease for purposes of immunology. However, there is no real idea of whether catching Omicron confers any ongoing immunity or protection against more severe Covid-19 variants, or even against repeat Omicron infections.
The questions
For purposes of policy, and to assist the public to choose their own response, the questions to be answered are
- Will the Omicron outbreak pass through the whole population or will it peter out like previous outbreaks, once those who do not socially distance are infected?
- How severe is it? How deadly?
- Does Omicron give any kind of extra immunity or provide antibodies for other variants? Conversely can one be re-infected with Omicron? Is it effectively a 'separate disease'?
Finally we have the economic question - does action to prevent or eliminate a disease cost more than allowing the disease to run its course? How should the relative costs be appraised for the severity of diseases?
1. Omicron outbreaks
Since December 2021, weekly cases have risen globally to over 3 times the level of previous outbreaks but deaths have not yet risen as the outbreak is too recent (there is typically a four-week lag, and deaths are still falling in many countries from the receding Delta outbreak).
The Omicron variant was first observed in South Africa in late November, and rapidly spread to sub-Saharan Africa, the Netherlands, Britain and Australia. Within several weeks it had spread to all the original major Covid sites in Europe and the Americas.
- South Africa peaked Omicron infections within four weeks, whereas previous outbreaks took seven weeks. The Omicron outbreak has not been as big as the earlier beta or delta outbreaks (beta was the most dangerous). Three weeks after the peak, deaths are still high and possibly rising, but running at about half of previous outbreaks. One study says 8% of the infected are dying, so if true it it is a very dangerous disease. As well, much of the improvement is due to antibodies from prior Covid infections. Unprotected, Omicron was said to be similar in virulence to the original Covid-19.
- In Zambia, Omicron peaked in three weeks. Deaths are still rising but may be only 1/5 of previous outbreaks.
- In Kenya the Omicron outbreak may have peaked in only two weeks, and there have been less than 100 deaths.
It still remains to discover whether the small size of outbreaks in Africa results from better disease control, from some kind of 'natural immunity' or are just due to limited testing capacity.
Outside of Africa, a far more massive number of cases has overwhelmed testing facilities so it is hard to say what is happening. However:
- In the UK the Omicron outbreak has been running since the end of November 2021. In the graph, it appears to have peaked ten days ago, with daily cases now about 45% of the maximum. Allowing for symptomless cases, about 28% of the adult population may have been infected with Covid-19 in 21 months up to 1 December. Since then, about one in seven adults have had Omicron. There has been a steady improvement in the case mortality rate since the beginning of the pandemic. In April 2020 it was 20%, in November 2020 through January 2021 it was 2%, in September 2021 following general vaccination it was 0.4%, and now case mortality appears to be below 0.2%.
- Australia now has the highest per-capita infection rate in the world, due to the authorities perversely abandoning most social distancing measures as the current outbreak progressed. Australia was Covid-zero and an exemplar for the world until June, but, 'snatching defeat from the jaws of victory', there are now over 130,000 cases in a day or 700,000 in a week. In the largest State New South Wales, the outbreak has been running for six weeks and may have topped out around 7 January - though this is unclear because of a badly interrupted testing regime. A new round of infections may result from a proposed further relaxation of isolating rules for key workers. Total confirmed cases in the present outbreak so far have been about 700,000, 12% of the adult population of NSW.
In terms of the progress of the outbreak, Omicron is just like previous variants with a clear peak and rapid decline once most of the undistanced and their contacts are infected - except that it moves faster in both directions, Outside of Africa it is infecting a higher proportion of the population than past outbreaks - perhaps because people and governments have been taken by surprise. The rapid advance of the outbreak has meant people have not distanced quickly enough or well enough for a very transmissible infection. 'Lockdown exhaustion' is also an issue.
2. Severity
Omicron symptoms are similar to the original virus, but with a higher incidence of upper-respiratory complaints such as runny nose, sore throat and headache. It also does not often involve a loss of smell or taste. It appears to have quicker incubation than other variants, and to be less serious on average. Nevertheless it is still a killer - through the sheer volume of cases. Australia has recorded its highest number of daily Covid-19 deaths over the past few days.
It seems that once in ICU, chances are just as bad as they ever were. There is about a 35-40% chance of being intubated, and once intubated, there is a 40-50% chance of death. The difference with Omicron is the low level of ICU admissions for the vaccinated. In Australia this is said to about 0.2% of confirmed cases.
The U.K. Health Security Agency said individuals with omicron are 50% to 70% less likely to require admission to a hospital. This tallies with South African estimates. However most patients were under the age of 40.
Using the UK figures above, it appears that vaccination has reduced mortality by a factor of five, and Omicron has a case mortality 2-3 times below Delta. This division of effect is rubbery. Medical authorities in NSW are saying that the chance of being in ICU is 13 times higher for the unvaccinated - which would imply that virtually all the drop in severity is due to vaccination, not Omicron. However - a high proportion of those dying currently appear to be vaccinated.
These figures may be biased by the young age of the infected population. Procedures to protect age care facilities etc are now considerably improved, which may also be lowering the mortality rate.
These figures may be biased by the young age of the infected population. Procedures to protect age care facilities etc are now considerably improved, which may also be lowering the mortality rate.
3. Prevention
Any disease can be stopped at the border with sufficient political will and organisation. New Zealand has been tolerating a Delta outbreak since October with minimal lockdown, but it has intercepted 273 Omicron cases at the border. Taiwan is struggling to contain entry of Omicron. China has specifically decided Omicron is too dangerous to allow it loose and continues to employ its zero tolerance policy quite successfully. There have been no deaths in China since February 2021.The main thrust of prevention has overwhelmingly been vaccination - to the point that little effort has been put into alternatives. From the beginning, some experts have warned that one of the risks of an vaccine-only strategy would be that it would encourage the rapid growth of a variant that could bypass vaccines - and that is exactly what has happened.
Several promising nasal sprays intended to provide eight-hour protection against infection are under development. The Covixyl-V spray was first announced as effective in July based on in-vitro tests, but there has apparently been no progress in obtaining emergency authorisation.
4. Immunology
Omicron does not seem to produce very much in the way of extra antibodies in the vaccinated, and we have no idea whether these antibodies might protect against other variants, or indeed against Omicron itself.
In the UK, it has been estimated that 10-15% of those with Omicron have previously been infected. Looking at the total numbers infected with Covid up to December - this would appear to be a substantial underestimate. The South Africans have been saying that prior infections are more like 80%.
Vaccination is doing little or nothing to prevent the spread of Omicron, although severity is substantially reduced. Booster vaccinations are agreed to improve antibody levels but the preventative effects on Omicron severity are not yet known.A booster 'jab' is said to reduce infectivity for eight weeks. Booster levels are relatively low - in NSW they are running at 26.5% - and there seem to be no evaluations of efficacy in the field. Pfizer say a specific Omicron vaccine will be available by March.
It is not known whether one can simultaneously suffer from Omicron and from other Covid-19 variants - which would make it truly a different disease. However - Omicron really does not seem to be all that different to original Covid-19 except in speed of spread and resistance to vaccination prevention.
Economic effect
It has been argued by proponents of lockdown that the straight economic cost of having a sick population exceeds the economic cost of locking down the population. This does not include the social and economic costs of medical intervention during a outbreak, or the cost of deaths, which add further substantial economic burdens
In Australia and other places where distancing and isolation are no longer practised with any assiduity, the current outbreak has led to substantial economic difficulties - similarly as states in the USA that remained open in late 2020. With up to 30% of critical workers off sick, other workers have had to bear heavy loads. Some businesses have closed due to lack of staff. Shortages of all sorts of items have been generated because of supply chain failures. Toilet paper and meat have once again disappeared from supermarket shelves. There has been a massive time cost as people queue for hours to get tested, or while they search for the few pharmacies carrying RAT tests.
Over the last week, the ANZ measure of spending in Sydney has actually fallen below lockdown levels.
Animal source?
Pandemicia has been suggesting for awhile that new variants might have been buried within animal populations, where their development would be hidden before they emerged in a mutated form. This has been suggested by variations of concern with multiple mutations, but no observed interim steps. A study has suggested Omicron is adapted for infecting mice, which might be the source for this variant. If it passed from the human population in 2020 as suggested, that might explain why it has similar severity to the original variant.Long covid
'Long Covid' continues to plague sufferers - to the extent that one woman who had initially been largely asymptomatic took her life rather than continue to endure the extreme effects. Up to one in three Covid-19 sufferers has some longer term symptoms. It is not known whether Omicron causes long Covid symptoms.
Summary
Data and information about the Omicron variant of Covid-19 are not available in any detail. The form of outbreaks appear to be fairly similar as with other variants, except incubation is shorter and peak values are reached twice as quickly. In Western countries, Omicron outbreaks are infecting a greater proportion of the population much more rapidly, causing testing facilities and supply chains to be overwhelmed.
Even with vaccinated populations, Omicron is causing chaos through sheer numbers of infections. Supply-chain problems have developed almost everywhere, with up to 30% of the workforce ill. The effect on consumer spending has been similar to past outbreaks which had lockdowns.
The fall in mortality in Covid-19 is actually a fall in ICU attendance. On its own, the mortality of Omicron may be similar to the original strain. For the average patient, mortality is very substantially lowered by vaccination, possibly more than ten times. The spread of Omicron is largely unaffected by vaccination.
Daily deaths in Britain are almost double those at the Delta peak. This should soon occur in Australia.
'Omicron triumphalism' - claims that 'the pandemic is weakening' because of 'natural selection to faster spreading variants' and that Omicron 'should be welcomed', are at best premature. There is no guarantee Omicron gives resistance to other variants. Clear evidence that Omicron is less severe than the original strain is also not forthcoming - though it is less severe than Delta and Beta.
As many governments are no longer enforcing social distancing, it falls on vulnerable groups who endure an unacceptable threat, such as the over-65s or the immune-compromised, to organise their own lockdowns. Fortunately, governments have now provided several years of training in how to do this, and some support remains.
Pandemicia expresses its gratitude to the many front-line medical workers fighting to save lives under very difficult conditions.
Addendum 18 January
Deaths in NSW are now three times the September maximum. Almost all people who died today were vaccinated.
Victoria has declared a 'code brown' hospital emergency (cancels leave, defers services) because 4000 staff are furloughed. Cases there are also falling, while deaths are rising above September 2020 levels.
In South Africa, official figures show only 9% of the adult population had been infected with Covid-19 up to the start of December. However, a seropositivity test in Gauteng province suggested 72% had been infected. Seropositivity tests during the Beta outbreak a year ago only showed 20%. It is hard to take these results seriously as they veer around so much, just as early tests in the USA did.
Seropositivity in the UK has been surveyed as over 95% , which if true would suggest that almost all the Omicron cases were repeats. Also - around 60% of adults over 16 have had a booster in Britain. This kind of combined resistance might help to explain the low mortality, and why 'open' Britain had 'only' 200,000 cases a day at the Omicron peak; compared with 300,000 a day in France, which locked down.
Deaths in the UK will probably rise to over 4000 a week, with one death in 8 due to Covid-19. The impression must be that Covid-19 has not 'reduced in severity' and has no 'herd immunity' above which it disappears. It will never be defeated or endemic. It does however now 'compare favourably' with influenza, which delivers about 13,000 excess deaths per week at peak. There are about 26,000 confirmed deaths in a bad year in England and Wales, from influenza and pneumonia, and there have been 74,000 deaths in each of 2020 and 2021 from Covid-19, which remains far more deadly.
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