What sicknesses were there on the Mayflower?

Medicine in the seventeenth century was relatively scary; without a sound scientific understanding of the human body, receiving medical treatment from a doctor could usually do more harm than good. Due to this lack of understanding, issues onboard a ship, such as the Mayflower, could become prolonged as uncontrolled outbreaks ravaged the passengers. It is believed that about fifty passengers died during the Mayflower voyage due to contagious diseases and the lack of fruits and vegetables. Scurvy, caused by a vitamin C deficiency, has been a major problem during sea voyages throughout human history. If the individual receives vitamin C in a timely manner, they can recover. Scurvy causes fatigue and putrefies the gums of the inflicted. The lack of a healthy diet weakened the passengers, putting them at further risk of contracting diseases such as tuberculous and pneumonia. Keep in mind that healthier passengers had to tend the sick, which helped to spread disease.
http://www.histarch.illinois.edu/plymouth/Maydeaths.html

https://historyofmassachusetts.org/plymouth-colony-history/

https://www.themayflowersociety.org/the-pilgrims/children-on-the-mayflower