The fact that 50-60 schools across the country have been affected by reports of poisoning makes it highly unlikely that there was a coordinated poisoning campaign. Such a campaign would require a significant amount of planning, resources, and coordination, and it is unlikely that a single group or individual could carry out such a campaign across multiple schools in different regions of the country. MPI is a very plausible explanation and fits the facts of this case much better than an unprecedented mass poisoning.