Homeland Security Secretary Kirstjen Nielsen says that the United States will take "extraordinary" protective measures when it comes to immigrant children in custody, after a second Guatemalan child died in custody.

Neilsen will travel later this week to the US-Mexico border to observe medical screenings and conditions at Border Patrol stations, according to AFP.

New from @DHSgov: Secretary Kirstjen M. Nielsen Statement on Passing of Eight Year Old Guatemalan Child pic.twitter.com/ft7RK1RpPR — Sahil Kapur (@sahilkapur) December 26, 2018

"In response to the unprecedented surge of children into our custody, I have directed a series of extraordinary protective measures," she said, following the "deeply concerning and heartbreaking" death of eight-year-old Felipe Gomez, who collapsed after running a high fever while traveling with his father Agustin Gomez from the Western Guatemalan indigenous Chuj Maya community near the Mexican border.

Gomez was detained with his 47-year-old father at a crossing in El Paso, Texas, on December 18 and had been transferred to a New Mexico medical center showing signs of sickness on Monday, the CBP said. Staff diagnosed him with a cold but later discovered a fever. He was discharged at midday, with prescriptions for ibuprofen and the antibiotic amoxicillin. The boy was later sent back to the hospital suffering from nausea and vomiting. He died shortly before midnight on December 24. -AFP

Guatemala has called for an investigation into the boy's death, the cause of which has not been determined. Customs and Border Patrol (CBP) says that they would "ensure an independent and thorough review of the circumstances."

The first death of a migrant child happened on December 8, when seven-year-old Jakelin Caal Maquin became sick on a bus traveling from a New Mexico port of entry to Lordsburg, New Mexico. Her father said he has "no complaints about how Border Patrol agents treated him and his daughter," adding in a statement through his attorneys that he was "grateful for the many first responders that tried to save young Jakelin's life in New Mexico and Texas."

Nielsen has asked experts from the Centers for Disease Control and Prevention to investigate "the uptick in sick children crossing our borders" and to identify what further steps border hospitals should take in preparation, her statement said. Nielsen added that she has asked the US Coast Guard medical corps to assess and "make appropriate recommendations" about Border Patrol medical programs, and has sought additional medical professionals from the Department of Defense. -AFP

The United States is unable to cope with the thousands of migrant arrivals, US Customs and Border Protection Commissioner Kevin McAleenan said on Wednesday. "We need help from Congress. We need to budget for medical care and mental health care for children in our facilities," he told CBS News.

In the last two months, the Border Patrol has apprehended 139,817 people on the southwest US border, compared with 74,946 over the same period a year earlier, said Nielsen. Over 68,500 were "family units," and approximately 14,000 others were unaccompanied minors, she said, adding that the system has been pushed to a "breaking point."

Guatemalan migrant Augusto Mendoza, who brought his one-year-old son on the journey to El Paso, told AFP that he would "never" consider making the journey again.

"It's been very, very hard. I would never think about doing it again, I regret it for my son," said Mendoza - whose wife and children were separated from him at the border and released from detention on Christmas day.

Medical challenges

DHS officials say that all children in border patrol custody will now be given comprehensive medical examinations, backing McAleenan's commitment to "secondary medical checks," with an emphasis on those under 10-years-old.

"It is now clear that migrants, particularly children, are increasingly facing medical challenges and harboring illness caused by their long and dangerous journey," said Nielsen.