MEXICO CITY — The U.S. Embassy in Mexico has narrowed its travel warning for the Caribbean city of Playa del Carmen amid what it calls an unspecified “ongoing security threat” just as the spring holiday season is kicking into high gear. The revised restrictions now say U.S. government employees must avoid five neighborhoods in and around a tourist center filled with hotels, bars and restaurants, but lift a blanket ban that had included several all-inclusive resorts.

Friday’s alert also clarifies that the threat is separate from issues with ferries between Playa del Carmen and the island of Cozumel.

On Friday, CBS News correspondent Anna Werner reported that the resort, not far from other tourist hot spots like Cozumel, Cancun, and Tulum, may seem like a tropical paradise, but it has not been spared the violence sweeping other parts of the country.

An explosion on a tourist ferry last month in Playa del Carmen left at least five U.S. citizens injured. Undetonated bombs were found on another vessel owned by the same ferry company less than two weeks later.

In January 2017, a shooting at a nightclub in the resort town left five people dead, including an American teen who was trampled while trying to escape.

Over the past year, there has been a dramatic increase in violence in and around Playa del Carmen, according to Eric Olson, an expert on security issues in Mexico at the Wilson Center’s Latin American Program.

“There are American victims, but they tend to be bystanders, people at the wrong place at the wrong time,” he says.

The number of foreign visitors to the resort town jumped more than 18 percent last year, and CBS News travel editor Peter Greenberg says the number of Americans killed in violent crimes in Mexico is very small.

“Every time the United States issues a travel advisory, it’s got such a negative connotation, there’s an almost immediate knee jerk reaction from people to cancel,” says Greenberg, “but in terms of Americans being targeted for violent crime, it doesn’t really exist.”

An airline trade group predicts more than 42.5 million people will fly on U.S. carriers during this holiday season. That’s up three and a half percent from last year.

Flying is considered the safest way to travel, but it can still have problems. Two Southwest jets made emergency landings this week, and a United Airlines plane skidded to a stop in San Antonio when its landing gear collapsed.

In October, at least two dozen people suffered minor injuries when an American Airlines plane burst into flames at Chicago’s O’Hare Airport, forcing 170 people to evacuate. Some of the passengers filed a lawsuit claiming American Airlines was negligent in supervising and directing the evacuation.

For decades, airlines have tried to capture the public’s attention about what to do in an emergency through safety videos, onboard demonstrations, placards in seat-back pockets and even cute animated cartoons. But if there’s one message flight attendants want the traveling public to know in an emergency, it’s to leave everything behind — including your carry-on, reports CBS News travel editor Peter Greenberg.

Seconds before takeoff, American Airlines Flight 383 came to an abrupt stop when its right engine became engulfed in flames.

“Everyone on the right side of the plane jumped up and jumped onto us because as soon as the explosion happened, there was fire,” said Sarah Ahmed Furno. The business traveler was inside the smoke-filled plane as panic set in.

“You can’t see anything and there’s absolute chaos in the cabin. So at that point there’s a stampede and everyone’s jumping on each other.”

Ahmed Furno is one of 18 passengers involved in a lawsuit against American Airlines and the plane and engine manufacturers, Boeing and General Electric. Among the allegations is that American “failed to instruct” passengers on “proper and safe evacuation procedures.”

Cellphone video taken onboard shows the plane’s overhead bins in the open position, indicating that some passengers took their carry-on bags with them when they left the plane.

“I saw two flight attendants at the front of the plane and they yelled at me and said, ‘Oh, leave your bag,’” Ahmed Furno recalled. “I was the last one off and I just — I ignored them and jumped down the slide.”

The incident is the latest in what’s becoming an alarming trend during aircraft emergencies. In August, passengers were seen heading for the door with their bags as smoke filled an Emirates Air Boeing 777 in Dubai.

Photos posted to social media showed the same rule being broken aboard a British Airways jet in Las Vegas last year, and after the 2013 crash landing of an Asiana plane in San Francisco.

For any aircraft to be certified as airworthy, flight crews have to demonstrate they can evacuate a fully loaded plane, with half the exits blocked, in less than 90 seconds. But the question remains — who’s training the passengers?

In a cabin simulator, Delta flight attendants are trained how to evacuate a fully-loaded plane. Everyone here knows what to do in emergency. But in a real-life disaster, the situation is far less predictable.

“Medical emergencies, decompressions, security — you name it,” said Pauline Harrison, a safety instructor with Delta Airlines. “Our biggest challenge is that people do want to take their luggage off an aircraft. Why in the world would you stop and take a selfie or take a bag or anything like that?”

“But we live in a selfie world where everybody wants to take that selfie,” Greenberg said.

“Yes sir, but that person that does that is going to keep you from getting out of that aircraft,” Harrison said.

Flight attendants said the problem lies in part with the safety video. As detailed and entertaining as they might be, they said passengers either don’t listen closely or worse yet, ignore the video altogether. That’s what happened before US Airways Flight 1549 made its famous emergency landing in New York’s Hudson River in 2009.

“Before the flight, only 12 of our passengers had read the safety briefing card and only about 24 had paid attention to the safety demonstration,” said CBS News aviation and safety expert Chesley Sullenberger.

Sullenburger was the captain of the legendary flight now known as the “Miracle on the Hudson,” in which all 155 passengers and crew survived. He fears it may not be until people die during an evacuation that the traveling public finally pays attention.

“Let’s hope that it doesn’t take a high body count in a horrific accident where people cannot escape to finally remind people that they must leave their belongings behind,” Sullenberger said.

American Airlines responded to the lawsuit with a statement issued to “CBS This Morning” saying: “We’re proud of our pilots, flight attendants, and other team members who responded quickly to take care of our customers under very challenging circumstances.”

In one final note of irony, Sullenberger said that on that miraculous day on the Hudson, passengers who grabbed their bags as they left the plane ended up losing them in the river. But those who followed instructions and left without their luggage eventually had their bags returned.

Trains see boost in passengers looking for an alternative to flying

In the post-pandemic world, while many travelers have been obsessed with airlines, ground stops, cancellations and delays, Amtrak’s ridership is bouncing back — more than doubling in the Northeast corridor, and 88% across the country. At the same time, Amtrak was strengthening its long-haul services, with trains like the Empire Builder, the Zephyr, the Sunset Limited and the Southern Crescent, the Southwest Chief and the Coast Starlight, to name a few.

And while we don’t yet have true high-speed rail yet in this country — and may never have it — there are some improvements in the service. And why don’t we have high-speed rail? Because Amtrak doesn’t own its tracks. The freight lines do, and they have no interest in high-speed rail.

That may also explain why Amtrak doesn’t exactly own a great on-time service record — because their trains often have to pull over to a siding to let a 100-car-long freight train lumber through.

At the same time, Congress has never properly funded Amtrak to allow it to grow and upgrade and to be able to reinvest profits in its product.

In some cases, Amtrak has brought back the dining cars. But even more important, Amtrak has announced a major upgrade to its fleet, with the new “Amtrak Airo” trains — with more spacious interiors and modernized amenities will be rolling out across the U.S. in about three years. The cars will feature more table seating, better legroom and more room for all your electronic devices.

Until then, there’s some good news. Amtrak doesn’t promote it very well, and most passengers don’t know about it, but Amtrak actually sells a USA rail pass. For just $499, you get to travel Amtrak for 30 days and up to 10 rides. It’s a great deal — and children under 12 ride for $250.

And with new high-speed routes launching in several European countries in the past few months — Spain, in particular, has new options for travelers as train operators compete and prices fall — train travel in Europe is an increasingly attractive option.

The Eurail Pass has never been a better deal. It now enables rail travel in 33 European countries, an expansion from the initial 13 countries, with prices starting at $218. One Eurail pass for $473 gives you two months of train travel.

One caveat: you must buy your Eurail pass in conjunction with your roundtrip airline ticket from the U.S. to Europe. You can’t purchase it once you get there. And you can even get a Eurail pass that’s valid for three months.

Savvy travelers know that even if you manage to sidestep that raging case of Ebola, you’re only an ice cube away from the dreaded Moctezuma’s Revenge (it’s also known as Montezuma’s Revenge, but why risk invoking the wrath of an Aztec ruler with anglicized spelling?).

We sat down with travel doctor and global adventurer Stacy Waneka to find out what precautions are really necessary before taking the next trip—in order to be safe, healthy.

A primary care physician with a specialization in travel medicine, Dr. Waneka’s job is to keep international travelers healthy, while easing fears over those dreaded vaccinations.

With a keen eye on the Center for Disease Control and Prevention (CDC) watch list, Waneka researches every destination, and proposes a tailor-made healthcare strategy that cheers you on with every passport stamp.

Dr. Waneka secured her passport at a young age, with a family move to Saudi Arabia, and has never stopped exploring. From motorcycling through India, practicing healthcare in Indonesia, hitchhiking through Malaysia, tackling Mt. Everest, even treating Kosovo refugees during the Bosnian conflict, she’s a maverick at shielding travelers from the real enemy on any trip—sickness.

According to Dr. Waneka, the secret formula for healthy travel is simple: Pack the most valuable tool of all … common sense. After all, you can’t get a prescription for that. Here are her top tips for healthy travel from a PeterGreenberg.com interview:

TRAVELER’S HEALTH KIT

There are the basic things that you just can’t leave behind, make sure you have some moleskin, sunscreen, basic allergy medication, Tylenol or Advil … it depends on what kind of travel we’re talking about. A good tip for backpackers is to take a sheet and sew it in half, so that it’s kind of like a sleeping bag, and that way you always have clean linens with you … so you’re not going to get scabies.

I always travel with Cipro, for traveler’s diarrhea. [Cipro is a brand name for a fluoroquinolone antibiotic, which can also be found under the name Noroxin.]

Imodium will slow things down whereas Pepto-Bismol is not going to do a whole lot. That 12-hour bus ride will be a lot easier if you’ve got some Imodium in your bag.

The other thing that I think is useful is hydrocortisone cream. Also, people with allergies need to make sure that they are traveling with Epi-Pens (epinephrine auto-injector). Insect repellants (with DEET) can be a big help when you have to worry about mosquitoes.

Oral re-hydration packets are another one of my favorites, so if you do start getting dehydrated or you do get a diarrhea, [these] can go a long ways to making you feel a lot better. It’s easier to maintain health with re-hydration than it is to find something locally.

FOREIGN PHARMACIES

Pharmacies in other countries are less reliable than what we have in the U.S.

Again, depending on geography: Mexico, for instance, is generally pretty reliable if you’re getting Cipro … Southeast Asia on the other hand has a huge influx in false drugs in the market and it’s not a place to fill prescriptions.

That’s why I generally send people with the prescriptions that they would need. Get it filled here and take it with you, so that you don’t have to worry about that.

BOTTLED OR TAP?

Bottled water, period. If you are going to be camping or trekking at all, then that’s where iodine tablets come in extremely handy ….

Again that’s why it’s so helpful to go to someone to help prepare, because so much of it depends on what kind of travel you’re going to be doing. The different recommendations can really be tailored to a specific itinerary and it will make all the difference in the world.

When you are traveling anywhere outside the U.S., Canada, Western Europe, Australia, and New Zealand, you need to be thinking about bottled water.

If it’s not bottled, don’t drink it. And, remember, ice cubes don’t come from bottles.

WHERE DISEASES LURK

The African continent will probably always be our most difficult place in terms of infectious disease. It’s where we see things like yellow fever, malaria and meningitis, and they still do have outbreaks of Ebola—although it’s not something that travelers need to worry about as much but it’s an occupational risk.

[However], Costa Rica and Belize are probably the two most common travel spots that I hear people talk about where they’ve never stopped to think about typhoid, hepatitis A, and malaria.

Austria is a place where we commonly see tick-borne encephalitis (TBE). The Europeans get vaccinated. We don’t even have the vaccine for TBE in the U.S.!

If you’re going to be backpacking for two weeks, you need to think about this. If you’re going for a weekend to a ski resort—not such a big deal … There’s a big difference in exposure between a common tourist and an adventure tourist and a business traveler, and somebody who is going to do missionary work. All of those have a different level of risk and they need different recommendations.

TO VACCINATE OR NOT TO VACCINATE?

The most frequent question is, “Do I really need that vaccine?” People don’t like to do the vaccinations. Vaccines themselves seem so scary in our culture … The answer is yes! I mean the risk of exposure through travel far outweighs the risk of the vaccine itself.

It’s important to realize that there are three categories of things to think about for any country … You have to think about what a normal adult needs for basic preventive medicine. Then you have to think about what’s recommended for the traveler, and that’s where you get into, “Well, what’s endemic in that country?” Things like hepatitis A, typhoid and malaria.

Then you have to look at what’s required. Certain countries have vaccinations that are required for entry or exit. And that’s where it helps to go to somebody who stays current with the CDC recommendations and knows why they have those and what to do about them.

Your routine vaccination would be tetanus and make sure that you had your childhood measles, mumps and rubella. You would need to consider hepatitis A and typhoid vaccinations. Hepatitis B is increasingly recommended for travelers, and then you have malaria prophylaxis.

Some [vaccines] are just single injections and that gives you lifetime immunity, some are single injections that require boosters in several years. Some of them are a series of injections and you need two or three over the course of months.

Travelers usually get their vaccines within the last 30-45 days prior to departure. We also have accelerated schedules for vaccinations, which are becoming more popular. Very rarely does somebody come into me six months before a trip.

FOREIGN FOOD RULES

[Eating foreign foods] is the best part of the trip! I’ll be the person in the night markets; I’ll be the person eating out of the stalls.

Cooked foods are generally as safe as they can be. The uncooked rule is if you can’t peel it, don’t eat it. I know that’s a cliché, but it’s such a good one to remember. It really does make all the difference in the world.

[The rules apply] in Mexico, even if you’re just going down to Rosarito, Ensenada, the places that seem like they really are just an extension of the U.S. … Don’t order the garden salad.

WAITER, I THINK THERE’S A PARASITE IN MY SOUP

You can’t necessarily tell by symptoms … but when you have a bad diarrhea and you’re feeling sick, you should always assume that it is bacterial and treat it. And if it doesn’t respond to the antibiotics, then seek healthcare.

If you’re still sick when you return, see your doctor, because that’s when you do have to worry about amoeba and parasites that don’t respond to antibiotics.

FINAL WORDS

Ask! If you have a question, ask! And, at the very least, people can go to the www.cdc.gov website. That is the definitive traveler’s resource.

If you have a question, ask! And, at the very least, people can go to the www.cdc.gov website. That is the definitive traveler’s resource. Think! Common sense will take care of just about any situation, whether we’re talking about safety issues, or food issues, or exposure issues.

Common sense will take care of just about any situation, whether we’re talking about safety issues, or food issues, or exposure issues. Prepare! Common sense is most useful with preparation. …It’s preparation in terms of vaccines, languages and knowing where you’re going, and knowing the culture and the customs and a little bit about the geography. Preparation in terms of your basic supplies. Make sure you’ve got the right clothing, and the right footwear. I remember trekking in Nepal with a young New Zealander who had sneakers. Here we are hiking up to Everest Base Camp and he had the worst blisters … and he ultimately had to stop the trek and go back down because he just wasn’t prepared.

Common sense is most useful with preparation. …It’s preparation in terms of vaccines, languages and knowing where you’re going, and knowing the culture and the customs and a little bit about the geography. Preparation in terms of your basic supplies. Make sure you’ve got the right clothing, and the right footwear. I remember trekking in Nepal with a young New Zealander who had sneakers. Here we are hiking up to Everest Base Camp and he had the worst blisters … and he ultimately had to stop the trek and go back down because he just wasn’t prepared. Go! People get afraid and they are concerned about the risks that we take when we travel and all of this stuff being said, go, enjoy it! There is so much out there that we should love and learn and if we don’t take the chance and we don’t put ourselves out there then I think that we really miss out on a lot.

[Editor’s Note: Be prepared that insurance doesn’t always cover travel consultation fees or vaccines. Make sure to also check with your health insurance policy to clarify coverage before traveling to a foreign country.]

For more travel health information, visit:

Dr. Waneka’s Travel Advice: www.drwaneka.com/Travel.htm

The Center for Disease Control and Prevention: www.cdc.gov/

The World Health Organization: www.who.int/en/

U.S. Department of State: www.state.gov/ for extensive overviews of countries, culture, as well as current U.S. Foreign Relations—all valuable information to have upon entering a new country, and the content is often more current than travel guidebooks.

By Margaret Emery for PeterGreenberg.com.

Get more information on staying healthy on the road with Travel Health & Fitness.

Find out how to keep your self safe on the road with Travel Safety & Security.

Previously by Margaret Emery:

Off the Brochure Travel Guide: Brussels, Belgium

Off the Brochure Travel Guide: Antwerp, Belgium

Off the Brochure Travel Guide: Tallinn, Estonia

Tips from a Travel Hero: Charles Veley, the World’s Most-Traveled Man

Traveling With Allergies: How to Buy Clean, Think Green and Travel Light