Thirteen more cases of COVID-19 in Hidalgo County were reported Sunday afternoon, bringing the total to 99.

The cases were reported to the county from late Friday through Sunday, according to a news release.

“As investigators dig deeper in all the known infections, they are beginning to discern patterns suggesting how the spread of the disease is unfolding in Hidalgo County,” Eddie Olivarez, the chief administrator of Hidalgo County’s Health and Human Services Department, stated in the news release. “Health officials now believe they are seeing 13 different clusters of infection that emanated from people who contracted the virus earlier but have since spread it to others.”

Of the 99 confirmed cases, 49 are related in some way as part of a cluster.

“This ‘community spread’ is a precursor to a quicker rate of infection in Hidalgo County,” Olivarez said.

The 13 individuals include residents of Mercedes, Mission, La Joya, McAllen, Donna, Alamo, San Juan, and Hidalgo.