Immigration from Mexico to the USA: all people who come from Mexico and do not yet have a health pass must first of all go to the sanitary control waiting room. Hundreds of people are waiting there every day - on some days their number is in the thousands - for medical check-ups. Those who come to USA for a short visit as tourists are quickly cleared, while seasonal workers and immigrants, on the other hand, often have to spend a whole day here and subject themselves to strict tests. Children's health is also strictly examined. Off camera two men, who are experts from the Ministry of Health of Cambodia, are studying the methods of quarantine in El Paso, Texas