Month: January 2023

TL&DR Major infectious diseases, RSV, flu, Strep A, and even Norovirus are back to their “normal” seasonal pattern, although numbers remain higher than pre-pandemic. COVID is going down, but I expect another wave to start in a couple of weeks’ time.

COVID

The rate at which COVID cases and hospitalisation numbers are declining is slowing down and the virus is not disappearing. I expect that this is a precursor of another wave.

As discussed in the previous posts, overlaying the number of deaths in each omicron wave (with some additional scaling for the two early ones) shows a remarkable similarity of each wave. The most recent data seem to follow the same pattern:

As always the last 203 data points should be ignored. If the same pattern follows again, I expect the current wave ending in about 3 weeks (day 70 on the plot above) when the deaths will start climbing up again, with a peak about a month afterwards.

So, expect a peak in deaths around April-May, with cases peaking a couple of weeks earlier.

Flu

Flu cases are dropping down very fast an indeed the proportion positive is lower than in a similar 2019-20 season. Expect the last point to be revised upwards, with a possible tailing off, but the flu season is largely past.

RSV

Very similar pattern to flu, RSV cases are decreasing and the overall pattern is very similar to the pre-pandemic years. Expect further decline and the effective end of the epidemic.

Scarlet fever

The scarlet fever infections are significantly higher this year than in previous ones, but again they seem to follow a similar seasonal pattern.

After an usually end-of-the-year peak, the numbers dropped over Christmas and New Year, but appear to be peaking up again. Expect a further increase, perhaps not the same levels as recently, with a peak in week 11, end of March, beginning of April.

TL&DR: My China COVID article is out in The Conversation, and I am quoted on Norovirus in The Times. COVID numbers are down, but expect a new wave starting soon.

Post-pandemic, RSV, flu, Strep A, and even Norovirus are back to their “normal” seasonal pattern, although numbers remain higher than pre-pandemic.

China

My article on China’s COVID outbreak and herd immunity was published on Monday and generated a lot of comments. It was a rather difficult piece to write but I am happy to with the end results.

For the sake of people in China, I hope the prediction of another massive wave in March/April is wrong, but there is a huge gap between the current immunity levels and those required for herd immunity.

Norovirus

More recently, I was asked to comment on the increased risk of Norovirus, following a report from Public Health Scotland. A screenshot from The Times article (behind the pay wall):

As I told Helen Puttick, the infectious diseases that do show a regular seasonal pattern – including Norovirus – are back to their “normal” behaviour, following a suppression during the lockdown and a period of abnormal behaviour when the restrictions were removed.

However, the number of cases is often higher this winter – RSV and Strep A hospitalisations are up, as are reported Norovirus cases. Why?

A detailed update on the major infectious diseases is in a separate post.

Another week, another update. TL&DR: all indicators are going down. We are not out of the woods yet, I think, but it is all good news for Covid, flu, RSV and even Scarlet fever.

COVID-19

Admissions and cases are both going down. As described in a previous post, the deaths basically followed the same shape as the last few waves, reoccurring roughly every 3 months.

A big wave has not materialised yet, so I expect this wave to peter out for another 2-3 weeks until it starts growing again.

Influenza

The numbers are definitely down, and it certainly looks like the 2019-20 season. I fully expect the numbers to continue falling down (although there might still be some upward correction to this and last week’s reading).

RSV

The rate and positivity are declining, and the wave starts looking like another pre-pandemic year. Hopefully, this means that the 2022 summer and autumn outbreak is now finished, and we are back to the seasonal pattern.

Scarlet fever

Scarlet fever cases are still high (note the logarithmic scale below), but dropping down. This decline from very high numbers might mask the fact that the disease usually peaks in late winter and early spring (or at least it was doing this pre-pandemic).

But I still expect we will struggle with it for at least several months before the big drop in summer.