South African Health Minister Joe Phaahla warned Friday that the country is on the brink of a fifth wave of the pandemic after an uptick in infections tied to Omicron sub-variants BA.4 and BA.5. Though no increase in hospitalizations or deaths has yet been noted, health authorities are worried that any increase would put pressure on the health system, which was badly hit when Omicron was identified there last November. South Africa has logged more than 3.7 million cases and more than 100,000 deaths since the pandemic began in early 2020.