The recent spike in cases of sudden, severe hepatitis in children around the world has been widely reported.

Recently, several news outlets have highlighted a possible link between cases and contacts with pet dogs.

The spike in hepatitis cases in children was first noticed in the UK, but has now been reported in Europe, Asia, and the Americas.

In a recent briefing paper, the agency reported a high number of "dog exposures" in these cases of severe childhood hepatitis.

To suggest a link, it's important to show not only that exposure to dogs in patients is high, but that it's higher than in unaffected children.

A second problem with the data is that if you ask enough questions, there's a strong probability that the answers to one or more questions may seem linked to cases.

So what are the possible causes of the spike in hepatitis cases in children, and might any of them be linked to dogs.

Equally, the lack of exposure to dirt as a result of handwashing, sterilizing surfaces, and other hygiene measures may have predisposed children to over-reactive immune responses (as has been suggested for allergic diseases), and the hepatitis may be caused by the immune response rather than a virus.

Fortunately, the incidence is still extremely low, and until there is better data parents should probably concentrate more on keeping an eye out for any symptoms in their children than on reducing their exposure to dogs.