Health
Japan has high food and water standards; tap water is generally drinkable in cities, but use normal food-safety judgment and extra care in remote areas. Summer heat/humidity can be severe; hydrate and reduce midday exertion. Prevent mosquito and tick bites in rural/wooded areas; JE risk is mainly rural/seasonal. Mt. Fuji reaches 3,776 m, so ascend gradually and watch for altitude symptoms. This is reference info, not medical advice.
Vaccinations
Consult a doctor or travel clinic before travel. Be up to date on routine vaccines, including MMR, polio, Tdap, varicella, influenza, shingles where appropriate, plus COVID-19. CDC suggests considering Hepatitis A for most travelers and recommends Hepatitis B for many unvaccinated travelers. Japanese encephalitis vaccine may be recommended for long stays, repeated travel, rural stays, camping/hiking, or uncertain itineraries; rabies pre-exposure vaccine is situation-dependent. Yellow-fever vaccine is not recommended or required for Japan entry.
eSIM / connectivity
eSIM is widely usable in Japan if your phone is unlocked and eSIM-compatible. Major local networks include NTT Docomo, au/KDDI, SoftBank, and Rakuten Mobile with broad 4G/5G coverage, though mountains and remote islands can vary. Travelers can arrange data through international roaming, travel eSIM providers, airport SIM counters, data-only SIMs, or pocket Wi-Fi; confirm hotspot, voice/SMS, and identity-registration limits before purchase.
Health/vaccine info is reference only, not medical advice — consult a doctor or travel clinic; defer to CDC/WHO and official sources (as of 2026-06-20).