JUAREZ, Mexico (Border Report) — Every migrant staying in a Juarez shelter will be getting a varicella vaccination this week, Mayor Armando Cabada said on Monday.

So will shelter employees who came in contact with any of the now 116 victims of the chickenpox outbreak that prompted the largest government-run refuge to shut its doors to new migrants last week, he said.

Cabada said two federal government health agencies, IMSS and ISSSTE, have promised to deliver 1,300 vaccines by Tuesday. The vaccines will be applied first to all the children and adults at the Leona Vicario federal shelter where the outbreak began.

Chickenpox is an infectious disease causing a mild fever and a rash of itchy inflamed blisters. It is caused by the herpes zoster virus and mainly affects children. It’s also called varicella.

Cabada also urged the migrants and people in his city, in general, to remain vigilant and seek medical attention if they notice symptoms of the highly contagious disease. Thousands of Central American, Cuban and other migrants remain in Juarez either hoping to apply for asylum in the United States or waiting for their next court appointment in El Paso, Texas.

Since last week, migrants being returned to Mexico under U.S. Customs and Border Protection’s Migrant Protection Protocols (MPP) program are being routed to church-run shelters. Additionally, healthy migrants at Leona Vicario are being separated from the sick and strict hygiene practices are being enforced there.

The outbreak began on Dec. 7, when a Honduran minor developed symptoms and spread the infectious disease to other children and adults at the shelter, doctors with the Chihuahua state Health Department said last week. Mexican officials said it was hard for them at first to gauge the magnitude of the outbreak because some victims of the disease take up to two weeks to develop the symptoms.

As of last week, shelter officials are urging all guests to practice frequent handwashing, common spaces are being kept as clean as possible and linens from beds utilized by the sick are being disposed of, federal and state officials said.

Most of the victims have been children between 5 and 14 years old, though several smaller children and eight adults have been diagnosed as well, health officials told Border Report last Friday. The shelter back then was holding 811 migrants, mostly from Central America; about half of the total shelter population consists of children.

Cabada said there is plenty of room for migrants at other shelters because new arrivals to the city have been scarce this month because of the cold weather.

Visit the BorderReport.com homepage for the latest exclusive stories and breaking news about issues along the United States-Mexico border.