There is an outbreak of Chicken Pox in a migrant shelter in Ciudad Juarez, Mexico,  a city right across the border from El Paso, Texas.  You might recall El Paso as the hometown of Beto O'Rourke, who says he wants to tear down all already-existing barriers on the border. 

From Mexico's Excelsior:

The federal shelter of Ciudad Juarez, Leona Vicario, was put under quarantine after 181 cases of Chicken Pox were confirmed.  No migrant can leave or enter the shelter.
Albergue migrante en cuarentena por 181 casos de varicela ["Migrant Shelter Quarantined for 181 Cases of Chicken Pox"), by Carlos Coria Rivas, Excelsior, January 22, 2020]

Note that the migrants in this shelter are non-Mexicans and they are right across the border from U.S. territory.  

In this shelter there are around 700 migrants, principally Guatemalan, Honduran and Salvadoran, who cannot leave the shelter while the outbreak of Chicken Pox is under quarantine. 

Chicken Pox is considered a children's disease and there is a vaccine for it.  But it should be taken seriously and adults can get it too. In fact, adult males, when they get it, often have a worse time of it than women and children.  Chicken Pox is usually not fatal, but it can be. 

And here we have an outbreak of Chicken Pox among  Central Americans who almost certainly traveled to Ciudad Juarez because they wanted to get into the United States. 

Here's what the CDC (Centers for Disease Control and Prevention) has to say about Chicken Pox:

Chickenpox is a highly contagious disease caused by the varicella-zoster virus (VZV). The virus spreads easily from people with chickenpox to others who have never had the disease or never been vaccinated. The virus spreads mainly through close contact with someone who has chickenpox.
Chickenpox (Varicella) Transmission, CDC

This is another reason we want a secure border. 

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