TIJUANA, Mexico — Alma Ruiz Ramos held her 3-year old daughter Carla at the entrance to the bright orange camping tent she shares with her husband and another 4-year-old daughter.

White streaks of lotion are drying on Carla's cheeks, forehead and body. She contracted chicken pox from another child at the migrant shelter in Tijuana where they have lived for the past month, waiting to claim asylum in the United States.

"Here, if someone gets sick, then everybody gets sick," Ruiz Ramos said while lightly coughing.

The family fled the southern Mexican state of Michoacán, where violence disrupted and uprooted their lives. After threats of violence and death from warring cartels, the family felt they had no choice but to leave and seek refuge in the United States.

But when they arrived in Tijuana in February, they faced a five-month waiting period. While they've been waiting, all four family members have gotten sick at one point or another.

Ruiz Ramos' tent is on a covered concrete patio. It's one amid several rows of camping tents, with only a narrow path to walk through.

As rain fell over Tijuana this week, water accumulated over tarps used to provide additional protection to the patio area.

Many shelters in Tijuana, including the one where Ruiz Ramos and her family are staying, are cramped. Dozens of newly arrived families mingle in tight quarters with other families who have been waiting in Tijuana for months. The situation presents the right conditions for certain illnesses to spread.

Alarm over the new coronavirus, which was infected more than 136,000 people around the world, has added a sense of uneasiness in Tijuana. It has prompted a push to get the city prepared.

On a given day, thousands of migrants move through Tijuana, across the border from San Diego. Health officials recognize this constant traffic makes the community especially vulnerable to communicable diseases such as chicken pox.

To date, there have been no confirmed positive cases of new coronavirus, or COVID-19, in Tijuana or surrounding areas. Mexico has so far only 12 confirmed cases, compared to the 1,264 cases reported in the U.S. as of Friday evening, according to the World Health Organization.

The potential for a new coronavirus outbreak in Tijuana is top of mind.

"The most important act is to avoid its transmission," Dr. Luis Carlos Robles Ibarra said. He's a doctor with Tijuana's Municipal Health Office. "The more people that we have concentrated in one area, that could favor its spread."

A unique situation

Health officials, shelter directors and migrant advocates in Tijuana said they want to make it clear: Migrants should not be treated as disease carriers and they shouldn't be stigmatized just for being migrants.

At the same time, they acknowledge the uniqueness of their situation, and an increased risk, possibly more so than any other border city along the U.S.-Mexico border.

Each morning, dozens of recently arrived migrant families gather at the Chaparral-San Ysidro border crossing to join the growing wait list, nearly one thousand numbers long, to claim asylum in the U.S.

Many of the new arrivals, such as Irma Campusano Galeana, have been traveling for days or weeks. She and her three children fled cartel violence in Guerrero. Her priority up until now has been to seek safety, so she admitted she hasn't been paying close attention news about COVID-19.

"I'm not worried about it," she said. "But I see there's people from all over here (in Tijuana), and I'm not sure how true everything is."

Just a few steps away, dozens of other families who have been waiting for up to five months gather daily, waiting for Mexican immigration officials to call their number so U.S. asylum officers can process their claims.

Across the border, U.S. officials continue returning migrants to Tijuana. That includes the handful of individuals sent back every day under the newly affirmed policy known as "Remain in Mexico." They're also sending back an average of 124 deported Mexicans though the Chaparral crossing each day, the most of any Mexican border city.

On top of that, there's about 1,400 migrants staying at 17 migrant shelters across the city, while thousands more are renting elsewhere.

Those numbers don't include legal border crossings between Tijuana and San Diego, which totaled a staggering 51.6 million last year, according to U.S. border crossing . That's roughly 141,000 people who cross the border daily.

"We don't know how Tijuana will fare in terms of infections later on, so we have to pay close attention," said Humberto Ibarra Ramirez. He's the director of the Casa de Oración del Migrante, a shelter that houses 40 migrant men in Tijuana.

Coronavirus detection training

In response to growing concern, the city's Municipal Health Office organized on Thursday the first of what they expect will be several workshops for the staffs of the 17 migrant shelters in Tijuana. Nearly two dozen people showed up, with questions.

During the workshop, the city's health office instructed shelter directors about how to identify the differences between symptoms of the common cold versus those for new coronavirus.

"Any person who shows those symptoms, and again, it's someone who has had contact with a confirmed case, or someone that is a suspected case and is under investigation, or someone who shows symptoms and came from impacted countries, then we have to investigate them more," Robles Ibarra said.

The city has established procedures on what to do if anyone at their respective shelters developed flu-like symptoms.

Those procedures streamline the process so that epidemiologists from the Baja California State Ministry of Health can provide immediate attention to individuals showing symptoms compatible with new coronavirus.

"The ideal situation is that you would notify the (state) ministry of health, and after that, they begin investigating that person, and doing all pertinent tests to confirm or discard the case," Robles Ibarra added.

Following the presentation, shelter staff members asked questions and shared some of their best practices and their own preventive measures.

Questions included where shelters can obtain cleaning and hygiene products, such as sanitizer and disinfectant spray. Stores around the city have run out of those products, leaving shelves empty until they can restock.

The city said it delivered some items to the shelters, though the supplies may not last long. Other participants said they've bought items on their own, or received donations. Others still said they've made do with what's available, such as making their own bleach solutions to disinfect shared spaces.

All attendees were in agreement that in addition to sharing personal hygiene tips with migrants, they also have to step up the number of times they clean and disinfect their shelters.

As part of prevention efforts, several shelters displayed signs or posters explaining in Spanish how to wash hands properly and other ways to avoid spreading illnesses.

At some shelters, such as Juventud 2000 — where Ruiz Ramos and her family were staying — volunteers from the U.S. side of the border visited and instructed migrant children on some of those same prevention practices.

Learning from a model shelter

Among best practices, Tijuana health officials pointed to one shelter.

Pro Amore Dei is located on Tijuana's west side and houses nearly 190 migrants, making it one of the largest shelters in the city. It occupies two floors on the slope of a canyon overlooking the city center.

Even before fears over COVID-19, director Leticia Herrera Hernandez said staff disinfected communal areas, beds and sleeping halls and any hard surfaces at the shelter at least three times a day.

During their four daily meals, she asks everyone to wash their hands before and after, and has each adult and child disinfect their utensils.

As migrants watched television at the shelter's communal areas, many wore face masks. Herrera Hernandez explained that they ask anyone with a cough to use it. They will hand them out to whoever needs one.

As she explained some of their procedures, she noticed a young child coughing into his elbow, something they've taught them to do. He wasn't wearing a face mask

"Criatura, my creature of God, where is your face mask? Go tell them to give you one," she urged him. The child got up and followed her instructions.

Even though she said that there's no certainty that COVID-19 will come to Tijuana and to her shelter, they can't let their guard down.

"If you have a lot of people, you really have to step up and do a lot cleaning," Herrera Hernandez said. "You have to double up efforts, and above all you have to tell your people, 'Thankfully the virus isn't here yet, but we have to try prevent it.'"

Have any news tips or story ideas about the U.S.-Mexico border? Reach the reporter at rafael.carranza@arizonarepublic.com, or follow him on Twitter at @RafaelCarranza.

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