EXCLUSIVE: The number of detainees who tested positive for COVID-19 in the Rio Grande Valley (RGV) Sector alone has increased by 900%, according to information obtained by Fox News.

There were 135 detainees who tested positive in the first two weeks of July alone, marking a 900% increase in confirmed positive cases compared to the previous 14 months.

MIGRANT ARRESTS AT SOUTHERN BORDER ROSE YET AGAIN IN JUNE TO 188,000, TOPPING 1M THIS FISCAL YEAR

The RGV sector is one of the main destinations for migrants crossing the border, seeing more than 2000 apprehensions each day and accounting for 60% of confirmed positive detainees in the U.S. Border Patrol custody.

This information was obtained exclusively from a slide distributed to RGV Border Patrol managers to share with agents to help them protect themselves from the virus.

In a local radio interview with KURV 710 AM Tuesday in McAllen, Texas, RGV Sector Chief Brian Hastings spoke about COVID cases among agents and said he’s had more than 40 of his agents test positive this fiscal year.

TRUMP-ERA DHS OFFICIALS WARN OF ‘CATASTROPHIC’ RESULTS IF ADMINISTRATION ENDS TITLE 42 BORDER EXPULSIONS 

Border Patrol does not typically test migrants when they are initially taken into custody -- instead they are tested when they are transferred, either to Department of Health and Human Services (HHS) custody if they are unaccompanied children, or to nongovernmental organizations if they are part of a family unit for transport into the U.S.

The Biden administration has been struggling to get a grip of the crisis at the southern border, which saw more than 188,000 migrants encountered in June alone -- including a 25% increase in the number of family units encountered.

Currently, the majority of those encountered are turned back due to Title 42 public health protections put in place during the Trump administration. Just under 105,000 of those encounters in June resulted in a Title 42 expulsion.

However, the Biden administration is not turning away unaccompanied children or most migrant families (just 8,000 encounters out of more than 55,000 migrant family encounters resulted in a Title 42 expulsion). 

SEN. JOHNSON SEEKS INFO ABOUT CRIMINAL ILLEGAL IMMIGRANTS, GANG MEMBERS ARRESTED AT THE BORDER

Furthermore, it is reported to be planning to end Title 42 for migrant families later this month, with other reports suggesting it would be ended altogether for single adults shortly after. 

Republicans and former Trump officials have warned of potential public health consequences if that were to happen, noting that many of the countries from where the migrants have traveled are often behind the U.S. in terms of vaccinations.

CLICK HERE TO GET THE FOX NEWS APP

"Mexico is not where we’re at, the Northern Triangle countries aren’t where we’re at, there are multiple countries in Western Hemisphere that are not where America is at when it comes to vaccines and dealing with COVID," former acting CBP Commissioner Mark Morgan told Fox News this month. 

"But they’re still going to open it up to people in these countries to come from, to transverse through to get to our country, and allow them in -- it’s absolutely endangering American lives and once again shows this administration puts America last and everyone else first."