The Pennsylvania Department of Health reported 4,746 new coronavirus cases on Thursday.Itâs the fourth day in a row the stateâs case count has gone up.Pennsylvania is one of a handful of states seeing the greatest surges in cases and hospitalizations."Itâs very concerning. I think the fourth wave of COVID is clearly here, and thatâs whatâs going on here in Lancaster and in Pennsylvania, said Dr. Joseph Kontra, of Lancaster General Health.Kontra points to a number of factors for the increase, including the spread of more contagious and potentially harmful strains of the coronavirus."Itâs not only the U.K. variant thatâs around, but we also know the New York variant is here. I think that combination of things, the population density and the fact that we are opening up a bit," Kontra said.Vaccines are proving effective against the new variants.But doctors are seeing more children and younger people testing positive for COVID-19.A group of Elizabethtown College students was among those who got their shots Thursday at the Lancaster County Community Vaccination Center."I think that especially since weâre on campus and that community living, I think thatâs really important to kind of do our part," Darci Ott said."A lot less anxiety just about being in public, so Iâm looking forward to that," Ashley Conway said.Kontra said immunizations are key."Thatâs the way we get out of this, and thatâs the way we shut down this fourth wave," he said.