Measles cases rise 300% globally in first few months of 2019

Let us try again. Elisabeth Mahase states:

"WHO warned that the actual number of measles cases would
be far higher than reported, as less than a 10th of cases are
estimated to be reported globally."

So, how do we know whether the fluctuations are real (bearing in mind we are anyhow only talking about reports) or an artefact of looking for cases? Should we just multiply by 10 to get the true figure irrespective of whether they are confirmed or not?

With due respect to Dr Anand [2,3] I really doubt whether epidemiologists can enlighten us further: the more you interrogate this data the more unsatisfactory it seems.

The WHO is neither without conflicts, nor does it have a good track record [4,5]. The BMJ should be more careful.

[1] Elisabeth Mahase, 'Measles cases rise 300% globally in first few months of 2019',
BMJ 2019; 365 doi: https://doi.org/10.1136/bmj.l1810 (Published 16 April 2019)

[2] JK Anand, 'Re: Measles cases rise 300% globally in first few months of 2019. Ms Mahase’s report', 17 April 2019, https://www.bmj.com/content/365/bmj.l1810/rr-1

[3] John Stone, 'Re: Measles cases rise 300% globally in first few months of 2019 - how long is a piece of string?', 17 April 2019, https://www.bmj.com/content/365/bmj.l1810/rr

[4] John Stone, 'Fear of the disease is not a reason for confidence in the product...', https://www.bmj.com/content/364/bmj.l1259/rr

[5] 'Trust WHO: The Business of Global Health', Al Jazeera 15 December 2018, https://www.aljazeera.com/programmes/specialseries/2018/12/trustwho-busi...