What is typhus on Anne and Margot frank?

Anne and Margot Frank both contracted typhus while imprisoned in the Bergen-Belsen concentration camp. Typhus is caused by bacteria transmitted to humans by lice bites, which cause intense fevers, headaches, body aches, chills, confusion, and even death.

In the overcrowded and unsanitary conditions of the concentration camp, typhus rapidly spread through the population. Both Anne and Margot became ill from typhus at the end of February 1945, shortly after reaching Bergen-Belsen. It's believed that one or both of them passed away around early March (the exact date still unknown today), though both their deaths were registered on Mar. 31, a little over a month before British Forces liberated the camp on April 15, 1945. They both passed because of this horrible sickness with typhus.