Malaria
Malaria
[Four Cueball-like children wearing party hats, a discarded balloon is lying to the right. There is text above:] We had a malaria party [And there is text below:] but it turned out not to be very much fun.

This comic humorously considers pox parties as a means of preventing malaria. In these "parties," adults bring their children to deliberately expose them to a communicable disease to promote immunity . This is commonly done for a childhood disease like chickenpox and measles instead of vaccination.
In this comic, we see four Cueball -like children in party hats with a balloon lying on the ground, suggesting a missing "celebrant."
Some illnesses are more serious for adults than children. For example, chickenpox is far less severe contracted as a child than as an adult, the latter sometimes ending in sterility, brain damage, or worse. (Note that shingles is not adult-onset chickenpox, but a condition occasionally developed by older people who previously had chickenpox.)  Having caught chickenpox once, a person's immune system has developed antibodies , reducing vulnerability to the virus. The antibodies create immunity for a significant period of time, possibly life. However, immunity through antibody creation is not usually an effective strategy against malaria. Contrarily, once one has suffered from malaria, it can recur on its own, even after apparent healing from symptoms. Thus, having a malaria party would not be a useful exercise, as many could suffer significant illness and die.
The title text blames "David" for the party, referencing the idea of children blaming each other for an idea that turns out poorly. A malaria party is likely to have more severe consequences than, for instance, a group of 10 year olds building a ski ramp in the backyard. 
Also it could be a reference to the Bible: when King David has to choose between three Threads, he chooses a disease for the whole people, lasting 3 days.
Malaria is a Mosquito-borne disease of humans and other animals caused by protists (a type of microorganism) of the genus Plasmodium . It begins with a bite from an infected female mosquito , which introduces the protists via its saliva into the circulatory system, and ultimately to the liver where they mature and reproduce. The disease causes symptoms that typically include fever and headache, which in severe cases can progress to coma or death.
At the end of the 1990s, a study reported what would turn out to be made-up health threats from MMR- vaccines , which created an MMR vaccine controversy and lower vaccination rates, even after they were exposed as false. This made pox parties more popular as the "natural alternative." However, even usually-"harmless" diseases like measles can (rarely) have complications and side-effects, up to and including death, which are by far more common and/or more severe than the actual health risks involved in vaccination. In the past 20 years, 2 Americans died from measles, both people with compromised immune systems. Also none, or late immunization, may create an immunization gap through which nearly extinct diseases can reenter a population (see e.g. Epidemiology of measles ). If this gap can be closed (or made small enough), it is possible to make a disease extinct. This was actually successfully done with smallpox , and is now attempted with the poliovirus (Causing poliomyelitis , also known as infantile paralysis).
[Four Cueball-like children wearing party hats, a discarded balloon is lying to the right. There is text above:] We had a malaria party [And there is text below:] but it turned out not to be very much fun.
