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Dozens of readers have recently written with questions about travel precautions amid infectious-disease outbreaks. I wanted to use this week’s newsletter to address what we know and who should consider additional vaccinations.
“My husband and I have been planning a trip to Europe to visit relatives,” wrote Isa from Virginia. “I was alarmed to read that there is polio in some of these countries. We are both vaccinated, but should we get another booster before we leave?”
The Centers for Disease Control and Prevention recently updated its global polio alert to encourage travelers to “practice enhanced precautions” when traveling to 30 countries where polio has been recently detected. That includes many countries in Africa and the Middle East, as well as some in Europe.
Note that the risk of polio is not equivalent in all these areas. Polio transmission is actively ongoing in Afghanistan and Pakistan, while in Germany, Poland and Britain, no new cases have been diagnosed, but the virus has been detected in wastewater.
The CDC recommends that all travelers verify they are fully vaccinated against polio. Those who have completed their immunizations but are at increased risk of exposure to poliovirus could receive a one-time lifetime booster.
I think the practical way to interpret this guidance is for travelers to consider both the destination and what they’ll be doing when after they arrive. A doctor traveling to provide medical care in Pakistan, where polio is endemic and actively spreading, should consider receiving a booster. But a tourist visiting Germany, where no cases of polio have been acquired since 1990, can consider the risk extremely low and probably hold off on the extra shot.
“I was born in a country that uses the [oral polio vaccine] and not the polio shot. Should I get the polio vaccine now?” asked Gail from Indiana. “What’s the difference between the two vaccines?”
There are two types of polio vaccines, the oral polio vaccine (OPV) and inactivated polio vaccine (IPV), which is given as an injection. Both are highly effective, with protection exceeding 95 percent in high-income countries. The United States and many other countries no longer use OPV — not because it is less effective but because, in rare cases, it can lead to vaccine-derived illness. OPV is still used in some resource-limited countries because it can be distributed quickly in large vaccination campaigns.
People who are fully vaccinated with OPV do not need to be revaccinated with IPV. Those who receive an additional booster would be given IPV.
Clarissa from Massachusetts has a sibling who lives in Britain. “There seems to be a mysterious meningitis outbreak there and a lot of controversy over who should get the vaccine,” she wrote. “Is the meningitis vaccine available to Americans? Should I postpone my trip to see my sister?”
British health officials are investigating a cluster of infections caused by meningococcal group B bacteria. So far, they have confirmed 21 cases and two deaths. The infections are apparently linked to exposure at a nightclub, and most of those affected are young adults.
The severity of these cases has drawn attention to the infection and differences in vaccination policy. In Britain, meningitis B vaccination is not routinely offered to older teens and young adults because although the disease can be very serious, it is rare, and most people exposed to the bacteria do not become ill.
It’s important to distinguish between vaccines that cover different subtypes of meningococcal bacteria. In the U.S., the CDC recommends that all children receive the vaccine against subtypes A, C, W and Y at age 11 or 12, followed by a booster in later adolescence. This vaccine does not protect against meningitis B, for which a separate vaccine is available to higher-risk young adults.
I don’t think the right takeaway here is that all teens should get the meningitis B vaccine or that people should postpone their travel to Britain. But this is a useful reminder for teens to be up-to-date on childhood vaccines. Moreover, clinicians and patients must be aware of meningitis symptoms such as high fever, stiff neck and confusion, since the illness can progress very quickly.
“Greetings from northern Utah, where I believe you grew up, too!” wrote another reader, Edith. “You may be aware that we are now the center of a measles outbreak. My daughter is visiting next month with her husband and their child. I’m leaning toward them canceling the trip. What do you think? Or can they just get a booster before coming?”
Indeed, the measles outbreak in South Carolina appears to be ending after 997 reported cases, just in time for a new spate of illnesses in Utah which has recorded more than 500 cases thus far. It highlights that even as we focus on risks abroad, ongoing dangers are not far afield.
If Edith’s daughter and son-in-law are fully vaccinated, they do not need additional boosters to protect against measles. The big question is regarding their child. The American Academy of Pediatrics recommends two doses of the measles, mumps and rubella (MMR) vaccine, with the first given between 12 and 15 months and the second between four and six years.
If Edith’s grandchild is fully vaccinated, they should be fine to travel to an area with ongoing measles cases. If the child at least 4 years old and close to the second dose, the parents could consider getting it earlier. But if they are an infant who has not yet received any doses, the situation carries much higher risk. Babies who live in outbreak areas can receive a dose as early as 6 months, but they still need to receive the full two-dose MMR series after the first birthday.
Thank you to everyone for writing. All of your questions underscore how crucial it is to curb vaccine-preventable disease. As infections spread, the risk increases for everyone, especially those who are most vulnerable.
The post ‘Should I postpone my trip?’ Your questions about outbreaks, answered. appeared first on Washington Post.
