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WebMD
3 days ago
- Health
- WebMD
Traveling? Measles Is Still Out There
— Planning a summer trip abroad? If you or your kids aren't fully vaccinated against the measles, you risk bringing home more than souvenirs. While measles cases in the U.S. seem finally to be slowing down, experts warn that international travel could reignite outbreaks and push the country's already high case numbers even higher. Since January, Texas has confirmed more than 700 measles cases, including 94 hospitalizations and two deaths. Across the country, outbreaks are also in 11 other states — in Georgia, Indiana, Kansas, Kentucky, Michigan, New Jersey, New Mexico, Ohio, Oklahoma, Pennsylvania, and Tennessee — with well over a thousand cases total nationwide, making 2025 the second-worst measles year since the illness was declared eliminated from the U.S. in 2000. While experts can't say for sure how these flare-ups started, many U.S. measles outbreaks trace back to international travel — when a partially vaccinated or unvaccinated person journeys to a country where the disease is still common, catches the virus, and returns home to a community with low vaccination rates. 'Measles has been historically eliminated from the U.S.,' said infectious disease specialist Nathan Lo, MD PhD, assistant professor of infectious diseases at Stanford University. 'That means that outbreaks in the U.S. (and in Texas) start with a travel-associated 'imported case.'' This travel season, health officials stress extra caution to protect yourself, your family, and your community. Navigating a Highly Contagious Disease Measles is one of the most infectious diseases in the world. The virus spreads when an infected person coughs or sneezes, and it can survive on a surface for up to two hours. If you're unvaccinated and around someone with measles, chances are very high — 90% — that you'll catch it, too. Countries with ongoing measles outbreaks include Romania, Ireland, Austria, India, Indonesia, Thailand, and many others. But even if you're traveling to an outbreak-free area, you can still be exposed. 'Airports and airplanes are easy places to get infected,' said Paulo H. Verardi, PhD, professor of virology and vaccinology at the University of Connecticut in Storrs. Protecting Yourself When Traveling Abroad There are only two ways to be fully protected against measles when you travel: through vaccination or natural immunity. Just about everyone should get two doses of a measles vaccine -- either the MMR vaccine (measles, mumps, rubella) or the MMRV vaccine, which combines the MMR vaccine with the varicella (chickenpox) shot. The second shot should occur at least two weeks before travel, according to the CDC. Exceptions include children under 6 months old, who are not eligible for the vaccine. Those whose mothers are vaccinated receive some protection passed during pregnancy, but it doesn't long — typically waning at about six months. Babies between 6 and 11 months should get one dose at least two weeks before they travel. Important: This early dose doesn't count toward the standard two-shot series — the child will still need to get two more doses later (at 12 to 15 months, and again at 4 to 6 years). If you were born before 1957, then you're considered protected through natural immunity. Prior to the vaccine, nearly everyone got measles — because, again, it's incredibly contagious — and measles infection triggers an immune response that continues to protect you decades later. What If You Can't Get the Measles Vaccine? Patients with weakened immune systems — like if you've had an organ transplant or are undergoing treatments like chemotherapy, radiation, or immunotherapy — might not be able to receive the vaccine. If that's you, then a conversation with your doctor belongs on your pretravel to-do list, said pediatrician David M. Higgins, MD, a pediatrician at the University of Colorado and Children's Hospital Colorado in Aurora. If you or your child can't get the measles vaccine, traveling — especially abroad and to parts of the U.S. with outbreaks — can carry serious risks. This is particularly true for children under 5, who are more vulnerable to severe complications from measles. Deciding whether to travel in this situation is deeply personal. 'There are many different degrees of immunocompromised, so it's really an individual decision,' Higgins said. Your health care provider can help you weigh the risks and explore options. If vaccination isn't possible and you decide to travel, take extra precautions. Make sure that everyone traveling with you is fully vaccinated. Stick to commonsense hygiene practices like washing hands often, avoiding high-touch surfaces, and wearing a mask in crowded or enclosed spaces. Also talk to your health care provider about what to do if there's a chance you've been exposed to measles. Post-exposure treatments like immunoglobulin may be given within six days of exposure — it won't replace the vaccine, but it could offer some protection or reduce symptoms. What If You're Not Sure Whether You've Been Vaccinated? Go ahead and get the jab. Experts say it's perfectly safe to get a booster, even if you've already had two shots. You can also ask your doctor to order an antibody test to check your immunity status, but these tests aren't always accurate and are not routinely recommended. 'For practical purposes, it's often easier to simply get vaccinated again rather than try to track down medical records,' Higgins said. What to Do If You Think You Were Exposed Abroad If you think you were exposed or start having symptoms, either abroad or back home, contact a health care provider immediately. The provider might recommend a measles test and ask whether you've been vaccinated. Measles can have a long incubation period — it could take up to two weeks after exposure for symptoms to show up. Early signs like fever, runny nose, cough, and red, watery eyes can feel like an ordinary virus, but eventually you'll see the telltale red bumpy rash and possibly tiny white dots with red rims in your mouth (Koplik's spots). 'There's typical management of the condition but also prevention of transmission, which means that a person needs to be isolated,' said Wassim Ballan, MD, division chief of infectious disease and associate director of the infection prevention program for Phoenix Children's in Phoenix, Arizona. Patients should isolate for as long as they are considered contagious — for four days before the rash appears and continuing until four days after it's gone.
Scientific American
16-05-2025
- Health
- Scientific American
See the Dramatic Consequences of Vaccination Rates Teetering on a ‘Knife's Edge'
Measles, rubella, polio and diphtheria—once ubiquitous, devastating and deeply feared—have been virtually eliminated from the U.S. for decades. Entire generations have barely encountered these diseases as high vaccination rates and intensive surveillance efforts have largely shielded the country from major outbreaks. But amid a major multistate measles outbreak that has grown to hundreds of cases, a recent study published in JAMA projects that even a slight dip in current U.S. childhood vaccination rates could reverse such historic gains, which could cause some of these maladies to come roaring back within 25 years—while just a slight increase in rates could effectively squelch of all four. 'We were quite surprised that we're right on that knife's edge,' says the study's lead author Mathew Kiang, an assistant professor of epidemiology and population health at Stanford University. 'A little bit more [vaccination coverage] and things could be totally fine; a little less and things are going to be quite bad.' On supporting science journalism If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today. The Centers for Disease Control and Prevention and the World Health Organization formally declare a disease eliminated when there is zero continuous transmission in a specific region for 12 months or more. The U.S. achieved this milestone for measles, a viral illness that can lead to splotchy rashes, pneumonia, organ failure and other dangerous complications, in 2000. Poliovirus, which can cause lifelong paralysis and death, was effectively eliminated from North and South America by 1994. The U.S. rid itself of viral rubella, known for causing miscarriages and severe birth defects, in 2004. And diphtheria, a highly fatal bacterial disease, was virtually eliminated after a vaccine was introduced in the 1940s. These are 'key infectious diseases that we've eliminated from the U.S. through widespread vaccination,' says study co-author Nathan Lo, a physician-scientist at Stanford University. Kiang, Lo and their colleagues ran multiple scenarios of childhood vaccination rates over 25 years to see if the four diseases would return to endemic levels (sustained transmission in which each infected person spreads the disease to at least one other person, on average, for a 12-month period). Measles—which is a very contagious disease and requires high population immunity to prevent spread—was the most susceptible to fluctuations in vaccination coverage. The models estimated that a 5 percent coverage decline would lead to an estimated 5.7 million measles cases over 25 years, while a 5 percent increase would result in only 5,800 cases. Polio and rubella would require sharper vaccination rate downturns (around 30 to 40 percent) before reaching comparable risks of reemergence. While projected diphtheria cases were notably lower, Lo notes that the illness has a relatively high fatality rate and can cause rapid deterioration: 'Patients with diphtheria get symptomatic and within a day or two can die.' Routine childhood immunization numbers have been slowly but steadily falling in recent years for several reasons, including missed appointments during the COVID pandemic and growing—often highly politicized—public resistance to vaccinations. 'The idea of reestablishment of measles is not outrageous and certainly in the moment where we're looking at erosion of trust through our federal authorities about vaccination,' says Matthew Ferrari, director of the Center for Infectious Disease Dynamics at Pennsylvania State University, who was not involved in the study. Reduced U.S. vaccination rates can also cause 'knock-on effects' that threaten disease eradication efforts around the world, Ferrari says. Additionally, recent funding cuts to international vaccine development programs such as USAID and Gavi, the Vaccine Alliance, will 'likely lead to increases in measles, rubella, diphtheria and polio elsewhere in the world,' he says. Outbreaks of these diseases in the U.S. largely start when unvaccinated American travelers pick one up while visiting a place where it's more common. 'If you now add the consequences of defunding vaccination around the world, then that's going to increase the likelihood of these cases coming to the United States,' Ferrari says, adding that the study authors may have made 'conservative assumptions' about these international factors. But Ferrari says the study's scenarios assumed immediate—and in some cases unrealistically high—vaccination rate drop-offs without accounting for other possible public health efforts to control disease. 'Even if we anticipated an erosion of vaccination in the United States, it probably wouldn't happen instantly,' Ferrari says. 'Detection and reactive vaccination weren't really discussed in the paper, nor was the population-level response—the behavior of parents and the medical establishment. That's something we can't possibly know.... From that perspective, I think the scenarios were enormously pessimistic.' Lo and Kiang argue that politically driven shifts in vaccine policy, such as reduced childhood vaccination requirements or a tougher authorization process for new vaccines, could make a 50 percent slump in vaccination rates less far-fetched. 'I think that there was a lot of pushback from very smart people that 50 percent was way too pessimistic, and I think that—historically—they would have been right,' Kiang says. 'I think in the current political climate and what we've seen, it's not clear to me that that is [still] true.' Kiang and Lo say that while their study shows the dangers of vast vaccine declines, it also highlights how small improvements can make a massive difference. 'There's also a more empowering side, which is that the small fractions of population that push us one way can also push us the other way,' Lo says. 'Someone might ask, 'What is my role in this?' But small percentages [of increased vaccination], we find, can really push us back into the safe territory where this alternate reality of measles reestablishing itself would not come to pass.'
Yahoo
30-04-2025
- Health
- Yahoo
Even a small uptick in vaccination could prevent millions of US measles cases. Here's how
Measles cases are continuing to spread throughout the U.S. with outbreaks in at least six states. Public health experts have previously said lagging vaccination rates are to blame for the rise in cases, at least partly due to vaccine hesitancy and vaccine fatigue left over from the COVID-19 pandemic. However, even a small uptick in MMR (measles, mumps and rubella) vaccination could prevent millions of infections, according to new research. MORE: Amid growing Texas outbreak, how contagious is measles? The study, published in JAMA last week, used a model to simulate the spread of vaccine-preventable infectious diseases across the U.S., evaluating different scenarios with different vaccination rates over a 25-year period. The Centers for Disease Control and Prevention (CDC) currently recommends that people receive two vaccine doses -- the first at 12 to 15 months and the second between 4 and 6 years old. One dose is 93% effective and two doses are 97% effective against measles, the CDC says. Most vaccinated adults don't need an additional dose. At current vaccination rates, the model predicts measles could once again become endemic -- constantly present -- in the U.S. with an estimated 851,300 cases over 25 years. If vaccination rates decline by just 10%, the model estimates 11.1 million cases of measles over 25 years. CDC data show vaccination rates have been lagging in recent years. During the 2023 to 2024 school year, 92.7% of kindergartners received the MMR vaccine, according to data. This is lower than the 93.1% seen the previous school year and the 95.2% seen in the 2019 to 2020 school year, prior to the COVID-19 pandemic. "That result -- that we're already at this tipping point for measles in the U.S. -- was a really striking finding that somewhat surprised us as well," Dr. Nathan Lo, study co-author and an infectious diseases physician at Stanford Medicine, told ABC News. "We continue to see measles outbreaks, but, by doing the study … you start to crystallize that result that even under the current levels of vaccine decline, there is a very feasible scenario where, over time, our country has measles return where it's a common household disease again." Dr. William Schaffner, a professor of preventive medicine at Vanderbilt University Medical Center in Nashville, who was not involved in the study, said the findings are a "well-thought-out worst-case scenario." "I'm not entirely sure that would actually happen because … the general level of vaccination remains pretty high, but there are pockets of unvaccinated children, and what you're seeing now is the fact that this virus has been reintroduced several times from other parts of the world," he told ABC News. "I think it's a bit of a worst-case scenario but, as a worst-case scenario, it's scary and, in that sense, reasonable." However, the model estimated that just a 5% increase in vaccination would lead to only 5,800 cases over the same 25-year period. This is because when more than 95% of people in a community are vaccinated, most are protected from measles through community immunity, also known as herd immunity, according to the CDC. MORE: Amid growing Texas outbreak, how contagious is measles? "My hope is that this study can provide that data to parents to say, 'This is the benefit of continuing to vaccinate your child. This is the kind of alternate reality that we're preventing. And yes, the risks aren't here right now, but perhaps not too far off,'" Lo said. Schaffner said there are pockets of the U.S. where MMR vaccination rates are 80% or less and vaccination rates would need to increase substantially in those areas to reduce the number of cases long-term. However, "if we increase the level of vaccination by a small amount that would reduce the risk of other small outbreaks here and there," Schaffner said. The study also found that a 50% drop in vaccinations would lead to an estimated 51.2 million cases over 25 years, but Lo thinks that would only occur if there were a large-scale policy change by the Department of Health and Human Services or the CDC to reduce or remove the childhood vaccine recommendation. As of Friday, the CDC has confirmed nearly 900 measles cases in at least 29 states. That number is likely an undercount due to delays in states reporting cases to the federal health agency. In western Texas, an outbreak has been spreading with 663 reported cases of measles, according to new data published Tuesday by the state Department of State Health Services. At least 87 people have been hospitalized over the course of the outbreak. Measles was declared eliminated from the U.S. in 2000 due to the highly effective vaccination program, according to the CDC. However, an outbreak lasting 12 months or more would threaten to end measles elimination status in the U.S. The Texas outbreak began in January of this year. To drive vaccination rates up, Lo and Schaffner recommend that parents who haven't vaccinated their children yet speak to their pediatrician to address their concerns. "We have to provide recommendations and let people know the facts that these vaccines are very effective and that they are safe," Schaffner said. "But we have to do more to try to reach out and provide reassurance, and this has to be done very much on a local basis." For example, when it comes to the community affected in Texas, Schaffner said they need local influencers they trust to turn to. "Speak with your local physician, health care provider, the person who cares for your children," Schaffner said. "Have a conversation with them, and that's our best hope for regaining some of this trust which public health had and which has slipped away." Even a small uptick in vaccination could prevent millions of US measles cases. Here's how originally appeared on
30-04-2025
- Health
Even a small uptick in vaccination could prevent millions of US measles cases. Here's how
Measles cases are continuing to spread throughout the U.S. with outbreaks in at least six states. Public health experts have previously said lagging vaccination rates are to blame for the rise in cases, at least partly due to vaccine hesitancy and vaccine fatigue left over from the COVID-19 pandemic. However, even a small uptick in MMR (measles, mumps and rubella) vaccination could prevent millions of infections, according to new research. The study, published in JAMA last week, used a model to simulate the spread of vaccine-preventable infectious diseases across the U.S., evaluating different scenarios with different vaccination rates over a 25-year period. The Centers for Disease Control and Prevention (CDC) currently recommends that people receive two vaccine doses -- the first at 12 to 15 months and the second between 4 and 6 years old. One dose is 93% effective and two doses are 97% effective against measles, the CDC says. Most vaccinated adults don't need an additional dose. At current vaccination rates, the model predicts measles could once again become endemic -- constantly present -- in the U.S. with an estimated 851,300 cases over 25 years. If vaccination rates decline by just 10%, the model estimates 11.1 million cases of measles over 25 years. CDC data show vaccination rates have been lagging in recent years. During the 2023 to 2024 school year, 92.7% of kindergartners received the MMR vaccine, according to data. This is lower than the 93.1% seen the previous school year and the 95.2% seen in the 2019 to 2020 school year, prior to the COVID-19 pandemic. "That result -- that we're already at this tipping point for measles in the U.S. -- was a really striking finding that somewhat surprised us as well," Dr. Nathan Lo, study co-author and an infectious diseases physician at Stanford Medicine, told ABC News. "We continue to see measles outbreaks, but, by doing the study … you start to crystallize that result that even under the current levels of vaccine decline, there is a very feasible scenario where, over time, our country has measles return where it's a common household disease again." Dr. William Schaffner, a professor of preventive medicine at Vanderbilt University Medical Center in Nashville, who was not involved in the study, said the findings are a "well-thought-out worst-case scenario." "I'm not entirely sure that would actually happen because … the general level of vaccination remains pretty high, but there are pockets of unvaccinated children, and what you're seeing now is the fact that this virus has been reintroduced several times from other parts of the world," he told ABC News. "I think it's a bit of a worst-case scenario but, as a worst-case scenario, it's scary and, in that sense, reasonable." However, the model estimated that just a 5% increase in vaccination would lead to only 5,800 cases over the same 25-year period. This is because when more than 95% of people in a community are vaccinated, most are protected from measles through community immunity, also known as herd immunity, according to the CDC. "My hope is that this study can provide that data to parents to say, 'This is the benefit of continuing to vaccinate your child. This is the kind of alternate reality that we're preventing. And yes, the risks aren't here right now, but perhaps not too far off,'" Lo said. Schaffner said there are pockets of the U.S. where MMR vaccination rates are 80% or less and vaccination rates would need to increase substantially in those areas to reduce the number of cases long-term. However, "if we increase the level of vaccination by a small amount that would reduce the risk of other small outbreaks here and there," Schaffner said. The study also found that a 50% drop in vaccinations would lead to an estimated 51.2 million cases over 25 years, but Lo thinks that would only occur if there were a large-scale policy change by the Department of Health and Human Services or the CDC to reduce or remove the childhood vaccine recommendation. As of Friday, the CDC has confirmed nearly 900 measles cases in at least 29 states. That number is likely an undercount due to delays in states reporting cases to the federal health agency. In western Texas, an outbreak has been spreading with 663 reported cases of measles, according to new data published Tuesday by the state Department of State Health Services. At least 87 people have been hospitalized over the course of the outbreak. Measles was declared eliminated from the U.S. in 2000 due to the highly effective vaccination program, according to the CDC. However, an outbreak lasting 12 months or more would threaten to end measles elimination status in the U.S. The Texas outbreak began in January of this year. To drive vaccination rates up, Lo and Schaffner recommend that parents who haven't vaccinated their children yet speak to their pediatrician to address their concerns. "We have to provide recommendations and let people know the facts that these vaccines are very effective and that they are safe," Schaffner said. "But we have to do more to try to reach out and provide reassurance, and this has to be done very much on a local basis." For example, when it comes to the community affected in Texas, Schaffner said they need local influencers they trust to turn to. "Speak with your local physician, health care provider, the person who cares for your children," Schaffner said. "Have a conversation with them, and that's our best hope for regaining some of this trust which public health had and which has slipped away."
Yahoo
29-04-2025
- Health
- Yahoo
Stanford researcher: U.S. at a ‘tipping point on' measles resurgence
Blood sample positive with Measles virus. (iStock / Getty Images Plus) A new report from the Centers for Disease Control and Prevention notes that the current measles outbreak marks the second highest annual case count in 25 years, and more than 80% of the nearly 900 current cases are associated with the 'ongoing outbreak in close-knit communities with low vaccination coverage' in New Mexico, Oklahoma and Texas. Overall, 96% of the cases have been among people confirmed as unvaccinated, or with unknown vaccination records. As of Tuesday, New Mexico had 66 cases, with no new ones reported yet this week. Most of the state's cases are in Lea County, just across the state line from Gaines County, Texas, where the outbreak began in mid-February. Measles, one of the most contagious diseases known to science, is a respiratory virus which is spread through contact with droplets from an infected person's speech, coughs or sneezes. Symptoms, such as fever, headache, red eyes, runny nose, and a spotty red rash, can take weeks to develop. People can spread measles days before they show symptoms. Heath officials say the best prevention from measles infection is two doses of vaccination. From Feb. 1 to April 25, 20,304 New Mexicans received a dose of the measles vaccine statewide, nearly double the 10,860 people over the same time last year, according to the New Mexico Department of Health. The national vaccination rate has slipped from 90.8% for one dose of measles, mumps and rubella, below the 95% threshold to prevent outbreaks from spreading. In 2000, after decades of vaccination, the CDC declared measles eliminated in the U.S., but if current vaccination rates continue, or decline further, measles may become commonplace again, according to research co-authored by Dr. Nathan Lo, an infectious diseases physician-scientist at Stanford University. 'It was striking for us, just seeing how much the U.S. was at this tipping point for measles, where small declines in vaccination can put us very certainly on the path for measles returning,' Lo told Source NM in a phone call. 'But also, small increases in vaccines can push us back into safe territory.' In research published in the academic journal JAMA last week, Lo and other researchers at Stanford used mathematical models to estimate how four serious diseases eliminated by vaccines in the U.S. (measles, rubella, polio and diphtheria) might reemerge based on vaccination rates. The models run thousands of simulations, projecting what the changes look like in the next 25 years. A 10% decrease in people choosing to vaccinate could spur an estimated 11 million measles cases over 25 years in the U.S. Even at the current levels of vaccination, measles could reestablish itself in the U.S. with hundreds of thousands of cases over 25 years. 'We're still very likely on the path toward measles return, but it won't happen for sometime,' Lo said, estimating that reemergence is about 20 years away. The state with the highest risk of measles: Texas. This is in part due to declines in vaccination rates, but also due to its large cities with international travel and demographic features, such as the age of the population. As for New Mexico, Lo said: 'One of the risks is being next to Texas, I think that's been made clear.' Prevalent measles infections would mean preventable illness-related deaths, often in children, and long-term injuries such as brain damage, he said. 'There's a number of rare but real neurologic complications that happen from measles; some of which are universally fatal and many of which lead to lifelong-disability,' he said. 'Those are the really unfathomable types of outcomes we hope don't come to pass.' For the other childhood diseases to reemerge, there would need to be a significant drop in vaccination rates, such as a 30% to 40% decline, he said. That's unlikely to happen without big policy shifts from the federal government, Lo said, such as changes to the childhood vaccine schedule, reducing potency of vaccines or revoking vaccines' uses. 'Suddenly, those scenarios of vaccine decline suggest that even rubella, polio and their really awful clinical complications such as babies born with birth defects and people living with lifelong paralysis or even dying, becomes much more of a risk,' Lo said. Lo said he hopes that not just policy makers, but parents and people considering getting a vaccine hear about the research. 'A small fraction of the population can really make a difference here,' he said. SUBSCRIBE: GET THE MORNING HEADLINES DELIVERED TO YOUR INBOX
