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Supposedly the World Health Organization is the top authority worldwide for public health. One would hope that they base their decisions on empirical data and not beliefs. However, from my perspective, they appear to be treating COVID-19 and influenza differently. In particular, according to their own figures, now COVID-19 is causing fewer deaths worldwide than influenza.

According to, WHO: COVID cases and deaths falling nearly everywhere:

In its latest weekly update on the pandemic, the U.N. health agency said confirmed cases dropped 12% to more than 3 million and reported deaths declined 22% to about 7,600.

That makes it around 1086 deaths per day worldwide. I have found other sources with similar figures.

And according to WHO, up to 650 000 people die of respiratory diseases linked to seasonal flu each year

The new figures of 290 000 – 650 000 deaths are based on more recent data from a larger, more diverse group of countries, including lower middle income countries, and exclude deaths from non-respiratory diseases.

The average of that is 470,000, which makes it around 1288 deaths per day.

Now, the first article also states:

Still, he warned that the pandemic was not yet over and urged caution, even as many countries have dropped their coronavirus protocols and segued into trying to live with the virus.

"The perception that the pandemic is over is understandable, but misguided," the WHO chief said. "A new and even more dangerous variant could emerge at any time, and vast numbers of people remain unprotected."

This last statement doesn't seem to clarify anything. A new and more dangerous influenza variant could also emerge, and most people aren't vaccinated for influenza. Also, new COVID-19 variants which appeared after the original were less lethal, not more. Case fatality rates have dropped continuously since the pandemic started, and the latest strain has been far less lethal than the original.

How is this situation different than influenza then? Does the World Health Organization have some objective parameter to determine that COVID-19 is still a pandemic and influenza is not?

Why does the World Health Organization still treat COVID-19 as a pandemic, when according to their own figures it is now causing fewer deaths than influenza?

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    Deaths and case fatality rates is not the measure of a pandemic. Jun 11 at 20:37
  • @anongoodnurse : then what is?
    – vsz
    Jun 13 at 4:25
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    Covid is more transmissible than the flu. Without lockdowns and masking, the number of daily deaths a very big indeed, as we saw in 2020 / 2021. WHO expects more variants to arise that evade immune response, therefore pandemic still active.
    – code_monk
    Jun 13 at 20:03

3 Answers 3

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In general, a pandemic is a disease that is spread across a large area. It is not based on case rates or anything similar, but rather on its global spread and potential threat to people. For example, you can visit this WHO EMRO site and see a group of diseases that are currently in pandemic or considered pandemic potential. Note that in some of these diseases only a small handful of people are infected each year, and even fewer die. For a close comparison to COVID-19, caused by SARS-CoV-2, you can look at MERS (Middle East Respiratory Syndrome), which is caused by another coronavirus, MERS-CoV. For this disease, since the disease emerged, there have been 2589 cases, with 893 deaths. To quote the linked pdf, note the last bullet point!:

  • At the end of March 2022, a total of 2589 laboratory-confirmed cases of Middle East respiratory syndrome (MERS), including 893 associated deaths (case–fatality ratio of 34.5%) were reported globally. The majority of these cases were reported from Saudi Arabia (2184 cases, including 813 related deaths) with a case–fatality ratio of 37.2%.
  • During the month of March 2022, one new case was reported.

So, from this, we can see that there was 1 case in the past month, but still considered pandemic or pandemic potential.

In the case of a comparison to influenza, the WHO has the same approach to this as they do to SARS-CoV-2, creating/recommending vaccines (I've worked on these personally at a WHO collaborating center), recommending treatments etc. However, sometimes, the various influenza viruses are not considered pandemic because they don't spread widely enough - this is particularly the case for things like the highly pathogenic H5N1 subtype, which can cause pandemics in birds, but so far haven't caused sustained transmission1 in humans, though local transmission does occur occasionally2. Occasionally a particular influenza spreads widely enough that it is considered a pandemic strain. A good example of this is the 2009 H1N1 pandemic strain.

Now, you are directly comparing influenza and COVID-19 in terms of deaths, remember that large parts of the world don't report their infections of anything properly because of lack of resources to do complete testing, lack of facilities, healthcare, politics, etc. The figures the WHO is reporting for case rates and deaths from SARS-CoV-2 infection are the confirmed ones, announced by the various governments. These are not estimates like the numbers provided for cases and fatalities in the influenza links you provided. It is highly likely that the SARS-CoV-2 case and fatality rates are much higher than reported given the conditions I mentioned above.

In addition remember that those countries reporting those numbers are those with the resources to do so, and those countries tend to be relatively wealthy, and as a consequence also have high vaccination rates, which we know drop infection and fatality rates significantly for SARS-CoV-2 infections 3 (this is just one of many scientific studies showing the same thing). Without the vaccinations, cases and fatalities would be much higher than influenza. In real terms, unvaccinated COVID-19 has a infection fatality rate that is an order of magnitude higher than influenza.

So, basically COVID-19 is still a pandemic because it is still causing widespread infection and a lot of deaths worldwide, which is the definition of a pandemic.

1: Maines TR, Chen LM, Matsuoka Y, Chen H, Rowe T, Ortin J, Falcón A, Nguyen TH, Mai le Q, Sedyaningsih ER, Harun S, Tumpey TM, Donis RO, Cox NJ, Subbarao K, Katz JM. Lack of transmission of H5N1 avian-human reassortant influenza viruses in a ferret model. Proc Natl Acad Sci U S A. 2006 Aug 8;103(32):12121-6. doi: 10.1073/pnas.0605134103. Epub 2006 Jul 31. PMID: 16880383; PMCID: PMC1567706.

2: Yang, Y., Halloran, M. E., Sugimoto, J. D., & Longini, I. M., Jr (2007). Detecting human-to-human transmission of avian influenza A (H5N1). Emerging infectious diseases, 13(9), 1348–1353. https://doi.org/10.3201/eid1309.070111

3: Lauring A S, Tenforde M W, Chappell J D, Gaglani M, Ginde A A, McNeal T et al. Clinical severity of, and effectiveness of mRNA vaccines against, covid-19 from omicron, delta, and alpha SARS-CoV-2 variants in the United States: prospective observational study BMJ 2022; 376 :e069761 doi:10.1136/bmj-2021-069761

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  • Comments are not for extended discussion; this conversation has been moved to chat.
    – Ian Campbell
    Jun 11 at 13:30
  • unless one of us is a WHO representative involved in the decision processes, then we won't be able to answer this definitively - I don't like the sentiment behind this. Shouldn't the public be able to understand WHO's decisions afffecting their daily lives without being insiders of the process of buddies with WHO staff?? Jun 12 at 8:51
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    @csstudent1418 No, not necessarily, just like you wouldn't expect your government to keep you informed at every step of a decision process. Their processes are generally transparent and they do keep and make available records of meetings etc, but exactly when the WHO will declare the pandemic over is their affair and will be based on predictions and assessments from a huge range of experts in many fields of biology, medicine, statistics etc.
    – bob1
    Jun 12 at 9:03
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Whether an outbreak of a disease is classed as a pandemic or not has absolutely nothing to do with the number of deaths or any other measure of the virulence or danger presented by the disease. It is only and exclusively based on whether the disease is very widely spread across the human population. Here's the WHO's own definition of the term:

an epidemic occurring worldwide, or over a very wide area, crossing international boundaries and usually affecting a large number of people.

And in case you think that's somehow political, here's a dictionary definition:

: an outbreak of a disease that occurs over a wide geographic area (such as multiple countries or continents) and typically affects a significant proportion of the population : a pandemic outbreak of a disease

As you can see, there is no mention of deaths or risks posed by the disease, or severity of symptoms or anything else other than geographic spread. This means that you could have a disease whose only symptom is a mild rash and which goes away after a single day and never ever kills anyone, but if it is widespread enough that would still be classed as a pandemic.

So whether the disease is causing more or fewer deaths than another, or indeed whether it is causing any deaths at all, is completely irrelevant to whether it should be classed as a pandemic.

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    @Pablo Both definitions in terdon's answer imply some level of novelty. We don't consider things pandemics once they are endemic; seasonal flu is considered endemic unless a particular strain is unusually pathogenic or otherwise exceptional, in which case it again gains the pandemic label. Seasonal flu is at least many decades old. COVID-19 is not.
    – Bryan Krause
    Jun 12 at 22:26
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    @Pablo Welcome to the real world, where problems are too multi-dimensional for any simple empirical criterion to be applied to everything.
    – Bryan Krause
    Jun 12 at 22:54
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    worth pointing out that if you reclassify COVID-19 from a pandemic to an endemic, that doesn't make it any better or worse. I've seen a lot of vaccine opponents saying stuff like "it's endemic now, so you don't need to stay at home or wear masks" which is just nonsense.
    – user253751
    Jun 13 at 8:35
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    @JonathanReez oh no, not at all! Like pandemic, so endemic: whether or not the disease is dangerous is completely irrelevant, the two terms only and exclusively refer to how common a disease is. For example, both HIV and malaria are endemic in certain parts of the world, but that does not make them "unlikely to do you any harm". Not even close!
    – terdon
    Jun 13 at 18:25
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    @JonathanReez I don't believe there's a layman definition of endemic. While the dictionary has several definitions of endemic, it's always about being native, not about danger.
    – prosfilaes
    Jun 13 at 20:21
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The WHO talked about this question long before COVID. In the article The classical definition of a pandemic is not elusive published in the Bulletin of the World Health Organization in 2011, the following is said about why only the 2009 influenza wave was declared a pandemic:

A pandemic is defined as “an epidemic occurring worldwide, or over a very wide area, crossing international boundaries and usually affecting a large number of people”. The classical definition includes nothing about population immunity, virology or disease severity. By this definition, pandemics can be said to occur annually in each of the temperate southern and northern hemispheres, given that seasonal epidemics cross international boundaries and affect a large number of people. However, seasonal epidemics are not considered pandemics.

A true influenza pandemic occurs when almost simultaneous transmission takes place worldwide. In the case of pandemic influenza A(H1N1), widespread transmission was documented in both hemispheres between April and September 2009. Transmission occurred early in the influenza season in the temperate southern hemisphere but out of season in the northern hemisphere. This out-of-season transmission is what characterizes an influenza pandemic, as distinct from a pandemic due to another type of virus. Simultaneous worldwide transmission of influenza is sufficient to define an influenza pandemic and is consistent with the classical definition of “an epidemic occurring worldwide”.

And further:

It is tempting to surmise that the complicated pandemic definitions used by the World Health Organization (WHO) and the Centers for Disease Control and Prevention of the United States of America involved severity1,10 in a deliberate attempt to garner political attention and financial support for pandemic preparedness. As noted by Doshi, the perceived need for this support can be understood given concerns about influenza A(H5N1) and the severe acute respiratory syndrome (SARS). However, conflating spread and severity allowed the suggestion that 2009 A(H1N1) was not a pandemic. It was, in fact, a classical pandemic, only much less severe than many had anticipated or were prepared to acknowledge, even as the evidence accumulated.

So... when would COVID cease being a "pandemic"? Given the WHO's pre-COVID definition this should happen when we get at least a full year of predictable seasonal spread. Given that Omicron's wave spiked all around the world near-simultaneously in January 2022, the earliest this can happen is January 2023, after which it will be declared a seasonal virus similar to the influenza.

It should of course be noted that the WHO's definition of a pandemic somewhat contradicts the layman understanding of what it means. I.e. the common expression the pandemic is not over yet! references the idea that we must take pandemic diseases seriously, as opposed to endemic or non-pandemic diseases like influenza or the common cold. Whether or not treating COVID seriously is important is a matter of debate, however technically speaking that's not what the WHO means by continuing to say that we're still in a pandemic.

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  • This updated answer is actually quite good! A quick note: COVID peaks globally were January 2021, May 2021, August 2021, January 2022, March 2022 so far. This does not look very seasonal yet. We will probably have another wave in this year‘s summer, which will complicate things even more
    – Narusan
    Jun 14 at 10:12

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