The year was 812, and the Maya had been suffering from drought for several years. A farmer from the Copan Valley turned to hunting to provide food for his starving family. Unfortunately, he contracted a disease from an unhealthy howler monkey he had killed. The disease quickly spread to his entire village and then to other Mayan communities. The Maya were already suffering from famine and drought and were unable to cope with the new disease. The Mayan empire fell. The disease, called papatlaca, spread throughout Central and South America.
The name for the disease papatlaca comes from the Nahuatl word meaning "to shiver". The Spanish often dropped a syllable and called it "paplaca", but they also referred to it as "temblar".
As the name indicates, the first major symptom of papatlaca is uncontrollable shaking of the entire body. Other symptoms include chills, coughing, difficulty breathing, massive swelling, and great thirst. Symptoms are much more mild in children than adults, and is much more survivable by children than adults.
Statistically; the disease is from 20% to 60% fatal in adults and from 0% to 5% fatal in children. The lower mortality rates generally apply when the victim is well cared for and the higher rates apply when the victim cannot find care. Once someone has survived papatlaca they cannot catch the disease again; they acquire a lifetime immunity.
In sparsely populated regions the disease would come and go in waves over the years and would often prove devastating. It was endemic, however, in densely populated regions, virtually guaranteeing that persons would be exposed to papatlaca in their youth, survive, and become immune to further infection.
Aztoltec (*Aztec) cities were large enough for papatlaca to be endemic. Further, there was a cultural requirement for families in outlying regions to travel to cities for special religious ceremonies. This often had the unintended benefit of exposing rural people to the disease in their childhood when the symptoms were relatively mild.
Papatlaca is a disease which first occurred in the 9th century, when the Maya civilization was collapsing, and there was already a massive die off due to famine. In the next century it spread throughout much of mesoamerica. and reached Peru. - It is important to note that the disease is not endemic on the Caribbean islands at the time of the Spanish arrival.
The Toltecs develop later than OTL. But because they develop a resistance to papatlaca sooner than their enemies, the Toltecs are able to expand further than in OTL, and they are a bit more resistant to outside attack.
The early Aztecs are pushed around by war until they found Temachtitla (as in OTL). This city is very defendable and forms a great base. The Toltecs as a nation are younger, larger, and more robust than in OTL so the Aztec do not so much conquer the Toltecs as merge with, and then rule them. Let's call this mesoamerican civilization the Aztoltec.
- 1492: Columbus discovers New World
- 1495: Smallpox epidemic in San Domingol (same as OTL) killing hundreds of Spanish and 75-80% of the natives
- 1515: Smallpox epidemic in Puerto Rico (same as OTL) killing 60-70% of the natives.
- 1516: Valvidas' expedition to Yucatan. Valvida and his men suffer from papatlaca. The survivors are fully recovered by they time they return to Hispaniola and the papatlaca is not spread there at this time. The New Maya suffer from smallpox epidemic.
- 1519: Cortes' expedition. Spanish exposed to papatlaca in Tanula but first symptoms do not occur until Cortes is in Cempoula. Cortes and many others die. Spanish return to Hispaniola.
- 1519 - 1520 Hispaniola ravaged by papatlaca. 50% of Spanish and 60% of African slaves die.
- 1520: Diego Columbus returns to New World as Admiral, Viceroy, and Governor. See: Chaos in the Americas
- 1520: Ships which travel back to Spain to warn of the disease, and to escape from the disease, end up actually bringing the disease with them to the Old World. This became known as the Spanish Scourge.
- 1521: Infected native from Yucatan spreads smallpox to Aztoltec Empire. One third of the population die (OTL figure).
- 1527: Smallpox reaches the Inca, 75% of population die (within OTL range)