旅行者としてデング熱に感染する確率はどのくらいですか？

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5/5 件の出典が引用元と一字一句一致することを独立して検証済み

1. [1] US Centers for Disease Control and Prevention (CDC) — Dengue — CDC Yellow Book (Health Information for International Travel) 検証済み 政府報告書

   Dengue — CDC Yellow Book (Health Information for International Travel)

   統計値

   ~390 million DENV infections and ~96 million symptomatic cases per year globally; 7,528 travel-related US dengue cases reported 2010-2021 with 3,135 hospitalizations and 19 deaths; >1,400 travel-associated US cases in 2019 and 2022-2024; 40-80% of DENV infections asymptomatic; up to 5% of symptomatic cases develop severe disease.

   抜粋

   “"The incidence of dengue among travelers to the tropics has increased in recent years, and dengue burden continues to grow in Sub-Saharan Africa, Latin America, and Asia, with estimates of 390 million DENV infections and 96 million symptomatic cases per year. … During 2010–2021, a total 7,528 travel-related dengue cases were reported in the United States; a total of 3,135 patients required hospitalization, and 19 died. … Travel-associated dengue case numbers also increased during 2019, and 2022–2024, with >1,400 cases reported each year, compared to a previous peak of 919 cases in 2016. … An estimated 40–80% of DENV infections are asymptomatic. … ≤5% of all people experiencing symptoms from dengue develop severe, life-threatening disease." ”

   出典データ

   2024-05-01

   アクセス日

   2026-04-11 · アーカイブ版

   検証

   グラウンディング監査の際、抜粋を引用元から独立して再取得し、原文と一字一句一致することを確認しました。

   計算過程

   CDC Yellow Book is the authoritative traveler-facing guidance. The ~96 million symptomatic infections per year across the ~4 billion people living in dengue-endemic areas implies a roughly 2% annual per-capita symptomatic rate averaged across endemic regions; travelers undersample the high-transmission rural pockets and over-sample urban areas and shorter exposure windows, so the per-trip figure for a two-week stay in a peak-season urban area lands roughly an order of magnitude below that (0.3–1%). CDC’s observation that US travel-associated cases jumped from ~919 in 2016 to >1,400 in 2019 and each year 2022–2024 anchors the “risk is rising, not falling” note in the body text. The 40–80% asymptomatic share is the basis for the ADE personal factor, and the ≤5% severe-dengue share is what takes the ~1-in-200 per-trip infection risk to ~1 in 4,000 per-trip severe-dengue risk.

   独立性

   CDC Yellow Book is the primary US traveler-facing clinical guidance, built from CDC dengue surveillance (ArboNET) and the peer-reviewed travel-medicine literature. Shares the Bhatt et al. 2013 modelled 390M/96M estimate with the WHO fact sheet below — treat the CDC/WHO modelled figures as one upstream; GeoSentinel (Duvignaud/Huits) is the genuine independent traveler-case stream.

2. [2] World Health Organization — Dengue and severe dengue — Fact sheet 検証済み 信頼できる参考文献

   Dengue and severe dengue — Fact sheet

   統計値

   100-400 million dengue infections per year globally; modelling estimate of 390 million infections with 96 million symptomatic; 2024 historic high of >14.6 million cases and >12,000 deaths reported to WHO; 308 locally-acquired cases in France, Italy and Spain reported in 2024.

   抜粋

   “"About half of the world’s population is now at risk of dengue, with an estimated 100–400 million infections occurring each year. … One modelling estimate indicates 390 million dengue virus infections per year, of which 96 million manifest clinically. … During 2024, ongoing transmission, combined with an unexpected spike in dengue cases, resulted in a historic high of over 14.6 million cases and more than 12 000 dengue-related deaths reported. … Dengue is spreading to new areas, including the European and Eastern Mediterranean regions. In 2024, 308 cases were reported to WHO from three European countries (France, Italy and Spain). … From January to July 2025, over 4 million cases and over 3000 deaths have been reported to WHO from 97 countries." ”

   出典データ

   2025-08-01

   アクセス日

   2026-04-11 · アーカイブ版

   検証

   グラウンディング監査の際、抜粋を引用元から独立して再取得し、原文と一字一句一致することを確認しました。

   計算過程

   WHO provides the global denominator and the 2024-2025 trajectory. The >14.6 million reported cases in 2024 — more than triple a normal year — is the main empirical basis for the “per-trip risk in 2024–2025 is higher than a decade ago” framing in the body. WHO case reports undercount the true infection total by roughly an order of magnitude (modelling gives ~96 million symptomatic vs ~14.6 million reported), but the year-over-year growth signal is robust. Independent of CDC: WHO pulls country-level case reports and the modelled Bhatt et al. burden estimate; CDC Yellow Book quotes the same modelled figure but uses its own US surveillance stream for the traveler-case counts.

   独立性

   WHO and CDC both cite the Bhatt et al. (2013) modelling estimate for the 390M / 96M figure, so that number is not independent between them. WHO’s 14.6M 2024 reported cases and CDC’s US travel-associated case counts come from different surveillance pipelines and corroborate each other on the 2024 spike.

3. [3] Journal of Travel Medicine (Duvignaud, Stoney, Angelo, et al.) — Epidemiology of travel-associated dengue from 2007 to 2022: A GeoSentinel analysis 検証済み 査読済み

   Epidemiology of travel-associated dengue from 2007 to 2022: A GeoSentinel analysis

   統計値

   5,958 confirmed or probable dengue cases in travelers evaluated at GeoSentinel sites 2007-2022; 50.4% acquired in Southeast Asia, 14.9% South Central Asia, 10.9% Caribbean, 9.2% South America; ~2% had complicated dengue; median travel duration 21 days; 67.3% tourism, 12.2% visiting friends and relatives.

   抜粋

   “"This analysis included 5,958 travellers with confirmed (n = 4,859; 81.6%) or probable (n = 1,099; 18.4%) dengue. The most frequent regions of acquisition were South East Asia (50.4%), South Central Asia (14.9%), the Caribbean (10.9%) and South America (9.2%). … In Southeast Asia, annual proportionate morbidity increased from 50 dengue cases per 1000 ill returned travellers in non-epidemic years to an average of 159 cases per 1000 travellers during epidemic years. … the median travel duration was 21 days … the most frequent reasons for travel were tourism (67.3%), visiting friends or relatives (12.2%) and business (11.0%)." ”

   出典データ

   2024-10-19

   アクセス日

   2026-04-11 · アーカイブ版

   検証

   グラウンディング監査の際、抜粋を引用元から独立して再取得し、原文と一字一句一致することを確認しました。

   計算過程

   GeoSentinel is the closest thing the travel-medicine literature has to a representative traveler case series. The 50 vs 159 dengue cases per 1,000 ill returned travelers (non-epidemic vs epidemic years) in Southeast Asia is a proportionate morbidity, not an attack rate — it describes what share of sick returning travelers have dengue, not what share of all travelers catch it — but the ~3× swing between epidemic and non-epidemic years is what anchors the regional_breakdown ordering and the seasonal personal factors. Median travel duration of 21 days in this case series matches the two-week reference trip used for the headline figure.

   独立性

   GeoSentinel is a global network of travel and tropical medicine clinics with its own case-reporting pipeline, methodologically independent of CDC US surveillance and WHO country-level case reports. Genuine independent corroboration on the regional distribution of traveler dengue (SE Asia dominates, Caribbean and Latin America are next).

4. [4] Annals of Internal Medicine (Huits, Angelo, Leder, et al.) — Clinical Characteristics and Outcomes Among Travelers With Severe Dengue: A GeoSentinel Analysis 検証済み 査読済み

   Clinical Characteristics and Outcomes Among Travelers With Severe Dengue: A GeoSentinel Analysis

   統計値

   Among 5,958 dengue cases in travelers 2007-2022, 95 (2%) had complicated dengue, of whom 27 (31%) were classified as severe; 91% hospitalized; one death (non-dengue-related).

   抜粋

   “"Of 5958 patients with dengue, 95 (2%) had complicated dengue. … 27 (31%) were classified as severe. … Seventy-eight (91%) patients were hospitalized. One patient died of nondengue-related illnesses." ”

   出典データ

   2023-06-20

   アクセス日

   2026-04-11 · アーカイブ版

   検証

   グラウンディング監査の際、抜粋を引用元から独立して再取得し、原文と一字一句一致することを確認しました。

   計算過程

   The Huits et al. analysis found 2% of traveler dengue cases had complicated dengue, and 31% of those complicated cases (27/95) met WHO severe-dengue criteria — i.e., 27/5958 ≈ 0.45% of all diagnosed traveler dengue cases were severe. This is much lower than the CDC Yellow Book’s “up to 5%” ceiling for symptomatic cases globally. The gap is consistent with the two populations: GeoSentinel travelers are adults with access to modern supportive care, while the global figure includes endemic-country pediatric second infections, which dominate severe-dengue incidence. The sole death was attributed to non-dengue-related illness. Applied to the headline 1-in-200 per-trip infection risk, the traveler severe-dengue risk lands on the order of 1 in 20,000–40,000 per reference trip, and per-trip mortality is roughly another order of magnitude lower.

   独立性

   Same GeoSentinel case pool as the Duvignaud et al. paper, so these two are not independent on the case count. They are cited for different purposes: Duvignaud for the regional distribution and traveler demographics, Huits for the severe-dengue and mortality fractions.

5. [5] US Centers for Disease Control and Prevention (MMWR Vol. 75, No. 18) — Increase in Travel-Associated and Locally Acquired Dengue Cases — United States, 2024 検証済み ↗ 1 other entry 政府報告書

   Increase in Travel-Associated and Locally Acquired Dengue Cases — United States, 2024

   See all 2 Likelier entries citing this source →

   統計値

   3,798 dengue cases reported from the 50 US states and DC in 2024 (a 359% increase above the 2010-2023 annual average of 828); 3,693 (97.2%) travel-associated and 105 (2.8%) locally acquired; locally acquired cases reported only from Florida (85, across 10 counties), California (18, three counties), and Texas (2, two counties).

   抜粋

   “"During 2024, a total of 3,798 dengue cases, including 2,252 (59.3%) confirmed and 1,546 (40.7%) probable cases, were reported to CDC from the 50 U.S. states and DC. Among these cases, 3,693 (97.2%) were travel associated, and 105 (2.8%) were locally acquired. … These represent a 359% increase above the annual average of 828 cases per year during 2010–2023. … Three jurisdictions reported locally acquired cases, including Florida (85 cases reported from 10 counties), California (18 from three counties), and Texas (two from two counties)." ”

   出典データ

   2026-05-14

   アクセス日

   2026-06-14 · アーカイブ版

   検証

   グラウンディング監査の際、抜粋を引用元から独立して再取得し、原文と一字一句一致することを確認しました。

   計算過程

   This MMWR report is the granular 2024 US case tally that anchors the new locally-acquired (autochthonous) caveat. Of 3,798 cases reported from US states/DC in 2024, only 105 (2.8%) were locally acquired — the other 97.2% were travel-associated, i.e. the population this entry's headline already covers. The 105 local cases were confined to three states and a handful of counties (Florida 85/10 counties, California 18/3, Texas 2/2), so the per-resident base rate for catching dengue without leaving the continental US is far below the per-trip traveler figure and is sharply concentrated in Aedes-range counties along the Gulf and southern California. No per-resident denominator is published here and the count is volatile year to year, so the caveat characterizes this risk qualitatively rather than quoting a "1 in N US residents" rate.

   独立性

   MMWR draws on the same CDC ArboNET surveillance pipeline as the Yellow Book source above — it is NOT an independent stream, just the granular 2024 jurisdiction-level case tally. Cited specifically for the locally-acquired vs travel-associated split, which the Yellow Book and WHO/GeoSentinel sources do not break out for the US.