By Andy Gallacher
BBC News, El Paso
Guards at the border crossing in El Paso are still being kept busy
El Paso is a border town in more than just name.
It is where the Mexican and American cultures merge into a colourful mixture of language, culture and food. Tex-Mex is the predominant dining experience here.
It is also one of North America's largest and most important border crossings.
Each day, about 100,000 people crowd onto four small bridges, making their way from Ciudad Juarez into El Paso.
Essentially, this is one city that happens to have two names.
Making a living
The situation here is starkly different from that of Mexico City.
Instead of empty streets and orders not to gather in large numbers, people here are huddled together on the bridges in huge numbers on a daily basis.
The fact is that most have to make the crossing. They study at the university, work or have family here.
The need to keep making a living seems to be outweighing fears about the H1N1 virus.
There is also some anger among residents. Many people feel that they are not being given enough information and few are bothering with paper masks.
On the border, though, agents say they are carrying out a procedure known as "passive surveillance".
It means that if anyone is seen with symptoms of the virus he or she can be pulled to one side and possibly quarantined.
Although there has been a great deal of talk about closing the borders, such a move seems highly unlikely.
President Barack Obama has acknowledged that isolating America and closing an economically important border is not feasible.
"I've consulted with our public health officials extensively on a day-to-day basis, in some cases an hour-to-hour basis. At this point, they have not recommended a border closing," he said.
"From their perspective, it would be akin to closing the barn door after the horses are out, because we already have cases here in the United States."
On Thursday, an entire school district in Texas was closed down as a precaution and 80,000 children were sent home. The first death in the US also happened in this state.
A hundred miles east of El Paso, in the tiny town of Fort Hancock, there are no high security fences and security cameras.
Like much of the border between the US and Mexico, there are plenty of places to cross, albeit illegally.
"We're not out here 24/7," says Deputy Sheriff Robert Wilson, who patrols the border as part of his duties.
"There's no way to monitor folks if they decide to cross from Mexico to the United States and if someone was infected with the disease then they would enter into the United States undetected."
The situation here is evolving rapidly, but there is also a measured calm.
People on both sides of the border are concerned, and perhaps a little frustrated, that more information is not being given out.
But there is also a need, primarily driven by basic economics, for Mexicans and Americans to keep on crossing this and other borders.
Mexico City, to many, feels like a distant place.
But as schools close and the number of confirmed cases inevitably rises, it is getting closer.