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How viruses spread on boats, to brains and more

Here's what to know about curbing viral spread on a cruise ship, when to worry about sinus infection symptoms and how to find an online doctor.
A couple kisses on the porch of their apartment as seen through hazy windows.

Most of us know more about how viruses spread now than we did a few years ago. Still fascinated by all things contagion? Here's the latest on avoiding illness on a cruise, how sinus infections spread to the brain(!), why tropical diseases are moving north + what to expect from Covid-19 + flu this fall. But first, click on stories that should go viral in the other way in...

  • The Checkup: do (and don’t do) this 
  • Cold You So: cruise ships + brains + tropics 
  • Healthcare: flu + Covid-19 updates

The Checkup

Sick or Swim?

A cruise ship seen in the distance leaving a wide harbor in a mountain pass during sunset.

When setting sail on a cruise, your first instinct might be to find the most lavish midnight buffet. But staff worry about a different kind of spread—the flu, gastroenteritis + Covid-19 that move fast when many people are in close contact.

What happens if you get sick onboard? Ships have medical centers akin to urgent care centers. There, they treat fevers, sore throats, mild injuries + other routine issues, with 1-5 sick beds per every 1,000 passengers. They can distribute OTC drugs like pain relievers or anti-nausea meds + fill medications they prescribe. But you’ll have to cover the cost + submit a health insurance claim afterward.

If you need more help? You may get dumped off at the next port.

Sail into details at the Washington Post.

Can a sinus infection spread to the brain?!

A white woman with long blond hair tied back wearing a striped sweater stands looking out a window while sipping from a glass.

Sinus infections happen when an irritant (like seasonal allergies or a virus) inflames + plugs up paranasal sinuses—cavities close to the brain. Such sinus problems are extremely common + nasal congestion often clears up on its own. But in rare cases, viral infections in the sinuses can linger, giving bacteria a home to root, reproduce and turn into a bacterial infection.

Can this bacteria spread to the brain? One study found that only 1-6 cases per million people develop into a life-threatening condition like a brain abscess—and those happened after a severe infection went undiagnosed + untreated.

What severe symptoms of a sinus infection should you watch during this heightened sinus infection season? Learn more in this Dr. B resource article.

Or explore our online sinus infection treatment

Movin' on up...

A young Latina woman with long black hair wearing a gray t-shirt and camera slung around her neck looks down and smiles as she walks through a lush tropical woodland.

You don’t need to sail south of the border to get a tropical disease. A new report shows that rising temperatures, long summers + flooding are moving illness-transmitting bugs north.

The US has native cases of West Nile. And leishmaniasis—transmitted by sandflies—is endemic in Europe and the US. Most people won’t experience leishmaniasis symptoms like small pimples or ulcer-like lesions—and most cases aren’t fatal. But those who do develop skin protrusions may have permanent disfigurement. And most physicians stateside wouldn’t think to test for the disease, given that most assume it's only contracted abroad.

Learn more at NPR.

Healthcare 411

What to know about the flu virus (NY Times). Influenza Type A causes 75% of early fall + winter cases. Type B peaks in February or March. In adults, they cause the same symptoms + risk factors. But Type B can be fatal for more children. Most cases don’t require antiviral treatment. So rest up, stay hydrated, prevent a spread + get your flu vaccine.

The most common Covid symptoms doctors are seeing in fall 2023 (HuffPost). Covid-19 now feels more like the common cold, with common symptoms like congestion, runny nose, dry cough, sore throat, headaches, fevers + fatigue. Severe symptoms include shortness of breath + chest pain. Vaccination remains the safest way to reduce risk. And high-risk people should start antiviral treatment within 5 days of symptoms. Start a $15 online consultation with Dr. B for same-day prescription care.

States are withholding vaccine information (YLE). We still have excess deaths because of Covid-19. States with high vaccination rates have lower death rates. Still, states that would most benefit from robust vaccination programs are pressing public health officials to keep quiet, harming those already facing inaccessible healthcare.

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