Do you catch monkeypox? -UnHerd

Just as we started to put off the two-year pandemic, the last thing everyone wanted to hear was that a new infection was spreading unexpectedly. But this is exactly what happened. By the end of April 2022, cases of monkeypox, a viral disease, were detected in several countries around the world. By the end of May, 57 people had been diagnosed with the disease in the UK and 100 more in about 14 countries.

However, the epidemic of monkeypox is very different from the epidemic of Covid. Covid spreads in the air, but due to the patient’s breathing droplets, monkeypox spreads primarily through skin-to-skin contact. And since the first outbreak happened between gay and bisexual men-many of the first cases can be traced back to Canary Islands pride events, Madrid saunas, and elsewhere-so far. , Most of the cases are between men who have sex with men (MSM).

That said, the disease is not unique to gay men, it is a sexually transmitted disease in the strict sense of the word, and it has the potential to reach a wider community. Even if this is not the case, it is important to understand how much monkeypox can spread between MSMs, minimize its damage, and understand the scale of public health problems. With that in mind, we gathered 10 predictors to discuss the possible consequences of monkeypox outbreaks. I tried to predict the size that could occur and what it would look like. ??

Note on prediction method:

Classic “Super forecastIn the model, the predictor needs to indicate the probability of a particular outcome as a percentage, such as “The UK votes to stay in the EU, 66%.” Prediction skills are evaluated by how well those predictions are adjusted — do 66% predictions occur in 66% of the time? — And how confident they are: Getting a 90% confidence prediction correctly is more rewarding than getting a 55% confidence prediction correctly. (On the other hand, get a 90% reliable forecast Wrong You will be punished more severely than making a mistake with 55% confidence. )

In this case, we do something similar, but in a sense the opposite. Predictors have shown values ​​in the range that 80% considered likely to contain true results. So, for example, considering that the number of monkeypox cases in the UK by the end of 2022 is 90% more than 500 and less than 10,000 is 90%, it is in the 80% range. It is 500 to 10,000.

Also, each showed a value of 50%. You can think of this as the easiest, central, and most likely estimate. Predictors are, as usual, evaluated for 80% chances of achieving an 80% chance, but by making reliable predictions, rather than being rewarded, by narrowing the scope. You will be rewarded. For each question, we also showed the median predictions for 10%, 50%, and 90% of the predictors. That is, if you get all 11 predictions and arrange them in order from minimum to maximum, one is in the middle.

question:

How many cases of monkeypox are there in the world? By the end of 2022?

• Estimated median 10%: 13,500
• Estimated median 50%: 45,000
• Estimated median 90%: 525,000

As of June 17There were 2,103 laboratory-confirmed cases of monkeypox reported to WHO. Predictors believe that even in the best realistic scenario, that number will be only a small part of the final total. The estimate of 10% of the median (that is, the low end) is 6 times higher. On the other hand, the median upper estimate is still negligible for a large number of over 500,000 when compared to the prevalence of Covid. By the end of 2020, there were over 80 million confirmed cases of Covid. -19, and the number of things that haven’t been detected many times.

However, it is important to note that predictors’ predictions are very different. Three of them pointed out that the virus spreads through skin contact and has a relatively low R number, but is mutated and can be easily transmitted. Some say: “We are concerned that a significant amount of genetic drift may occur and the situation may turn into a more harmful pandemic, as several slightly different strains have already evolved.”

Another quoted and said This paperThe virus seems to have a very high R internal MSM community, but R is less than 1. (The R value is the number of people the average infected person continues to be infected with.) However, they “may mutate to gain infectious benefits, perhaps through the respiratory tract, as it spreads. It will be higher. ” As a result, the predictor predicted 30 million infections in the 90th percentile. This is four times the highest in the group.

Other forecasters were more optimistic. The total was thought to be less than 80,000. Another, 200,000. Another person with relatively low estimates (median 40,000, 90th percentile 400,000) pointed out that “so far, transmissions across networks of close contact have been restricted.” Another person who had a very wide range (12-5 million) said: On the other hand, it may not be. “

These estimates are total Cases as well as confirmed ones. (One predictor said, “I expect much of the world to be very undervalued.”) It is impossible to accurately assess who has received this question correctly. Means there is.

How many cases of monkeypox are there in the UK by the end of 2022?

• Estimated median 10%: 6,000
• Estimated median 50%: 22,000
• Estimated median 90%: 85,000

As with global estimates, there was considerable spread. One (the same person who gave the 30 million high-end quote in the first question) said the number could reach 1 million in the UK for the same reason.

But overall, the predictors felt that the UK was better suited to manage spreads than most countries. “British surveillance is moving in the right direction,” one said. “And there is the first attempt at vaccination.”

But there were concerns. “So far, despite proper monitoring, we haven’t been able to control it particularly well,” wrote one. “This is the worst result of what experts wanted a month ago, probably because of the long incubation period. Especially given the pride, there are still plenty of opportunities for super-spreader events so far. There is relatively little caution, but awareness within the LGBT community should slow it down. “

As with the “global” question, the predictor was talking about the actual number of cases, not the confirmed cases. However, monitoring in the UK is likely to be fairly comprehensive, so the two numbers need to be comparable.

What percentage of global cases in 2022 will be male?

• Estimated median 10%: 50
• Estimated median 50%: 94
• Estimated median 90%: 99

Currently, more than 99% of the monkeypox cases recorded worldwide are male, suggesting that the spread was almost exclusively MSM. Overall, predictors felt that there was a clear possibility of over 10%, but that it could spread rapidly among the general public and completely wash away the start of a man’s head. I felt it, but I expected it to stay the same. One pointed out that when the disease goes out of the subpopulation where it started, it can behave very differently depending on the situation. There are more women with AIDS than men in Sub-Saharan Africa. Send mode does not keep the heterosexual community safe. There are far more heterosexuals than gays, so as the community begins to grow, the potential population will be much higher. “

Another predictor thought that this was basically the same question as the case number question and was somewhat repackaged. When it begins to spread very rapidly by means other than skin-to-skin contact, it spreads out of the MSM community. Currently spreading network. It is very difficult to estimate this risk, but I think it will increase as the number of cases increases. “

All 11 predictors thought that women’s cases were at least 10% likely to reach nearly 50% of the total, but most thought they didn’t. At 95% or more.

What percentage of UK cases in 2022 will be male?

• Estimated median 10%: 55
• Estimated median 50%: 98
• Estimated median 90%: 99

Forecasters felt that the story was likely to be about the same in the UK and around the world, but there are some caveats. First, they felt that the disease was better controlled here and more likely to spread more slowly, so it is less likely to spread outside the MSM community, thus a median as high as 10%. I did. Second, the UK’s HIV population noticed a higher proportion of men and women than the world average and used it to extrapolate monkeypox.

Overall, the attitude of the predictor can be summarized in this comment. “I think community expansion is definitely possible, but founder effects and (reasonably) slow expansion mean that the MSM community will dominate the numbers by the end of the year.” The UK government’s current strategy of vaccination of high MSMs is very good and “may solve the problem on its own,” he added. However, they added that the public message at this time is not particularly useful as it does not warn the at-risk community and tends to emphasize the risk to a wider society than the MSM group. They said it was worth changing it.

Conclusion:

Overall, the forecasting group felt that monkeypox would continue to spread both in the UK and around the world. However, they felt that the numbers remained relatively small and likely to remain predominantly in the MSM community, unless they were significantly mutated so that they could spread by means other than contact with the skin.

However, they also felt that there was a significant tail risk of much wider impact. They say that new diseases that appear to mutate relatively rapidly have the potential to achieve new means of diffusion, and that hundreds of thousands and even millions of cases are unlikely. Not.

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A version of this study first appeared Swift Center..