Shots Fired!
A 30-year-old business traveler is going to Mexico for a week. Which vaccine should you make sure is up to date to prevent a food/waterborne viral infection?
Hepatitis A vaccine
A patient is going to Kenya for a safari. Which medication, started just 1–2 days before departure, is effective for prophylaxis against chloroquine-resistant malaria?
Atovaquone-proguanil - Daily, start 1–2 days before travel, continue 7 days after leaving
Doxycycline - Daily, start 1–2 days before travel; some sources 1 day), continue 4 weeks after leaving
Incorrect: Mefloquine - Weekly, start 2 weeks before travel, continue 4 weeks after
Chloroquine - Weekly, start 1–2 weeks before travel, continue 4 weeks after leaving
A tourist develops watery diarrhea after eating street food in Egypt. What is the most likely pathogen?
Enterotoxigenic E. coli (ETEC)
A hiker ascending 3000 m develops headache, nausea, and fatigue within 12 hours. What is the likely diagnosis?
Acute Mountain Sickness (AMS)
A patient complains of nausea on boat rides. Which OTC medication could prevent this?
Dramamine (dimehydrinate) and Bonine (meclizine)
A 28-year-old traveler is flying to Ghana, and the entry requirements include a proof of vaccination against a viral disease. Which vaccine is this?
Yellow Fever vaccine
A traveler presents with fever and severe joint pain after returning from Brazil. They report multiple mosquito bites. No vaccine is approved in US yet. Which viral infection should you suspect?
Dengue fever
A patient has moderate traveler's diarrhea with fever and blood in the stool. Which commonly used anti-diarrheal should be avoided?
Loperamide
A hiker ascending 3000 m develops headache, nausea, and fatigue within 12 hours. Which prophylactic medication could help this hiker prevent these early altitude symptoms?
Acetazolamide
Which strategy helps a long-haul traveler adjust faster to a new time zone?
Manipulating circadian rhythm with light exposure, sleep, and meal timing
A medical student plans to volunteer in rural India. They ask about protection against a bacterial infection from contaminated food and water. Which vaccine options do you discuss?
Typhoid vaccine (oral or injectable)
A patient had a malaria infection in India 6 months ago and now reports fever again. Which species is likely responsible for relapse?
Plasmodium vivax - this species can form hypnozoites in the liver, causing relapses months to years after initial infection.
For moderate-to-severe traveler’s diarrhea in an adult returning from Southeast Asia, which antibiotic is preferred?
Azithromycin
A climber presents with ataxia, confusion, and severe headache after rapid ascent. Which life-threatening complication should you suspect?
High Altitude Cerebral Edema
A patch applied behind the ear prevents motion sickness by blocking which receptor?
Muscarinic acetylcholine receptor - scopolamine
A wildlife photographer is traveling to Thailand and will be handling animals. What pre-exposure vaccine should you recommend?
Rabies vaccine
A traveler to West Africa wants to start malaria prophylaxis. They have a history of depression and seizure disorder. Which commonly used malaria prophylactic should be avoided, and why?
Mefloquine – it can cause neuropsychiatric side effects, including anxiety, depression, and seizures, making it contraindicated in patients with psychiatric or seizure disorders.
Untreated typhoid fever may lead to which serious complication?
Septicemia or intestinal perforation
A hiker at 4000 m complains of dyspnea at rest and pink frothy sputum. What is the likely condition?
High Altitude Pulmonary Edema
A traveler crossing multiple time zones complains of insomnia and daytime sleepiness. Which short-acting supplement may help?
Melatonin
A 40-year-old aid worker is traveling to a coastal region of Africa with limited sanitation and recent outbreaks of a waterborne diarrheal disease. Which vaccine, administered orally, could reduce the risk of infection for this worker?
Cholera vaccine – oral, inactivated vaccine recommended for adults at risk during outbreaks, especially in humanitarian or endemic settings.
You are prescribing primaquine for liver-stage malaria eradication. Which enzyme deficiency must you rule out to prevent hemolysis?
G6PD deficiency
Oral rehydration solution works via which intestinal mechanism to enhance water absorption even during diarrhea?
Sodium-glucose cotransport (SGLT1)
Glucose and sodium are absorbed together, and water follows osmotically, allowing hydration even during diarrhea.
Which medication can help prevent HAPE by reducing pulmonary artery pressure?
Nifedipine or Sildenafil
Rapid ascent to high altitude can cause sleep disturbances due to fluid shifts and pulmonary hypertension. What is this called?
High-altitude periodic breathing
At high altitude, especially when ascending rapidly, the lower oxygen levels (hypoxia) trigger several physiological responses:
Hypoxic ventilatory response: You start breathing faster to compensate for low oxygen.
Periodic breathing during sleep: This manifests as cycles of hyperventilation followed by apnea or hypopnea. It’s sometimes called high-altitude periodic breathing (HAPB).
Sleep disturbances: The periodic breathing leads to frequent arousals, fragmented sleep, and reduced sleep quality.