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// ================================================================
//  DOCUMENT CONTENT
// ================================================================
const doc = new Document({
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  sections: [{
    properties: {
      page: {
        margin: { top: 720, bottom: 720, left: 900, right: 900 },
      },
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    headers: {
      default: new Header({
        children: [
          new Paragraph({
            alignment: AlignmentType.RIGHT,
            children: [
              new TextRun({ text: "Pertussis (Whooping Cough) | Epidemiology Fact Sheet", size: 16, color: "888888", font: "Calibri" }),
            ],
          }),
        ],
      }),
    },
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              new TextRun({ text: "Sources: WHO | CDC | ECDC | StatPearls | PMC        Page ", size: 16, color: "888888", font: "Calibri" }),
              new TextRun({ children: [PageNumber.CURRENT], size: 16, color: "888888", font: "Calibri" }),
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    children: [

      // ── TITLE BLOCK ──────────────────────────────────────────
      new Paragraph({
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        spacing: { before: 0, after: 40 },
        shading: { type: ShadingType.SOLID, color: BLUE, fill: BLUE },
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        ],
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        children: [
          new TextRun({ text: "Epidemiology Fact Sheet", bold: true, size: 22, color: "D6E4F0", font: "Calibri" }),
        ],
      }),

      // ── FIELD 1: DISEASE OVERVIEW ────────────────────────────
      sectionHeading("1.  DISEASE OVERVIEW"),
      spacer(),
      twoColTable([
        ["Disease Name",       "Pertussis (Whooping Cough)"],
        ["Causative Agent",    "Bordetella pertussis (gram-negative bacterium)"],
        ["Type",               "Acute bacterial respiratory disease; vaccine-preventable"],
        ["Transmission Route", "Respiratory droplets (coughing/sneezing); extremely contagious"],
        ["Incubation Period",  "7–10 days (range: 4–21 days)"],
        ["Infectious Period",  "From symptom onset up to 3 weeks if untreated"],
        ["Case Fatality Rate", "<1% overall; up to 1–2% in infants under 6 months"],
        ["Vaccine-Preventable?","Yes — DTaP (children), Tdap (adolescents/adults)"],
        ["Notifiable Disease?", "Yes, in most countries; notifiable to WHO"],
      ], ["Item", "Detail"]),
      spacer(),

      // ── FIELD 2: EPIDEMIOLOGY DATA ───────────────────────────
      sectionHeading("2.  EPIDEMIOLOGY DATA"),
      spacer(),
      twoColTable([
        ["Global cases reported to WHO (2024)",           "941,565 confirmed cases"],
        ["Estimated true global cases/year",              "~24.1 million cases (all ages)"],
        ["Why the gap?",                                  "Massive underreporting — adults/teens misdiagnosed as bronchitis; limited lab capacity in LMICs"],
        ["Estimated deaths/year (children <5)",           "160,700 deaths"],
        ["Global incidence (2024)",                       "~137 per 1,000,000 population"],
        ["Global DTP3 vaccine coverage (2024)",           "85% of infants worldwide (WHO)"],
        ["Unvaccinated children globally (2024)",         "14.3 million zero-dose children (WHO)"],
        ["Europe incidence rate (2024)",                  "54.9 per 100,000 — 8× increase from 2023 (ECDC)"],
        ["R₀ (Basic Reproduction Number)",               "12–17 — among the most contagious diseases known"],
      ], ["Metric", "Figure / Detail"]),
      spacer(),

      // ── FIELD 3: DESCRIPTIVE EPIDEMIOLOGY ───────────────────
      sectionHeading("3.  DESCRIPTIVE EPIDEMIOLOGY"),

      subHeading("Person"),
      twoColTable([
        ["Most vulnerable age",     "Infants <6 months — incidence 85.4/100,000; hospitalization rate 33.4% (CDC 2024)"],
        ["Age shift (recent trend)", "Immunity wanes 4–12 years post-vaccine → teens & adults now major reservoir"],
        ["Sex",                      "Slightly higher incidence & mortality in females, especially in infants"],
        ["Immunocompromised",        "Higher risk of severe disease and complications"],
      ], ["Factor", "Detail"]),

      subHeading("Place"),
      twoColTable([
        ["Highest global burden",   "Low-income countries in Asia, Africa, and Latin America — poor vaccination coverage & lab capacity"],
        ["Europe 2024",             "54.9 cases/100,000; infants <1 yr (318.5/100,000) and adolescents 10–14 yrs (204.2/100,000) most affected (ECDC)"],
        ["India / South Asia",      "Among top 10 countries with highest unvaccinated children; pertussis severely underreported"],
        ["High-income countries",   "Resurgence in UK, USA, Australia, France, Denmark, Korea despite high vaccination rates"],
      ], ["Factor", "Detail"]),

      subHeading("Time"),
      twoColTable([
        ["First case documented",   "1906 — Bordetella pertussis isolated by Bordet & Gengou"],
        ["Vaccine introduced",       "1940s (whole-cell wP vaccine); acellular aP vaccine from 1990s"],
        ["Cyclical pattern",         "Peaks every 3–5 years; cyclical resurgence is characteristic"],
        ["Post-COVID surge",         "2024: global cases 476% higher than 2023; Europe 8× surge; USA 5× surge"],
        ["Current trend (2026)",     "Declining after November 2024 peak — consistent with cyclical pattern (CDC)"],
      ], ["Factor", "Detail"]),
      spacer(),

      // ── FIELD 4: RISK FACTORS ────────────────────────────────
      sectionHeading("4.  RISK FACTORS"),
      spacer(),
      bullet("Infants under 6 months", ""),
      subBullet("Not yet fully vaccinated; highest incidence and death rate"),
      bullet("Unvaccinated or incompletely vaccinated individuals", ""),
      bullet("Waning vaccine immunity", ""),
      subBullet("DTaP/Tdap protection lasts only 4–12 years — teens and adults lose protection over time"),
      bullet("Household or close contact with a confirmed case", ""),
      bullet("Pregnancy", ""),
      subBullet("Infected mothers can transmit to newborns before their vaccines begin; also higher complication risk"),
      bullet("Immunocompromised status or chronic respiratory disease (asthma, COPD)", ""),
      bullet("Low community vaccine coverage", ""),
      subBullet("Reduces herd immunity threshold, allowing outbreaks even in vaccinated populations"),
      bullet("Healthcare workers", ""),
      subBullet("Occupational exposure risk; can transmit to vulnerable patients if unprotected"),
      spacer(),

      // ── FIELD 5: TRANSMISSION & PUBLIC HEALTH IMPACT ────────
      sectionHeading("5.  TRANSMISSION & PUBLIC HEALTH IMPACT"),

      subHeading("Transmission"),
      twoColTable([
        ["Primary route",         "Respiratory droplets from coughing or sneezing"],
        ["R₀",                    "12–17; one of the highest reproduction numbers of any known infectious disease"],
        ["Contagious period",     "From symptom onset up to 3 weeks if untreated; antibiotics reduce this significantly"],
        ["Asymptomatic spread",   "Teens and adults often spread unknowingly — present with mild prolonged cough only"],
        ["NOT spread via",        "Fomites (surfaces); not considered a significant environmental route"],
      ], ["Mode", "Detail"]),

      subHeading("Public Health Impact"),
      bullet("~24.1 million cases/year globally; 160,700 child deaths/year — one of the leading vaccine-preventable killers"),
      bullet("63% of infected infants under 12 months in the USA were hospitalized (CDC data)"),
      bullet("Post-COVID surge: global cases in 2024 were 476% higher than 2023 (WHO)"),
      bullet("Waning immunity means even well-vaccinated countries experience outbreaks — challenges traditional herd immunity models"),
      bullet("Significant healthcare costs from infant hospitalizations (median stay: 5 days)"),
      bullet("Estimated 5 undetected cases for every 1 clinically diagnosed adolescent/adult case"),
      spacer(),

      // ── FIELD 6: CONTROL & MANAGEMENT / PREVENTION ──────────
      sectionHeading("6.  CONTROL & MANAGEMENT / PREVENTION"),

      subHeading("Treatment"),
      twoColTable([
        ["Antibiotic of choice",   "Azithromycin (1st line); alternatives: clarithromycin, TMP-SMX"],
        ["When to treat",          "Most effective in early catarrhal stage (first 1–2 weeks); still given later to reduce spread"],
        ["Supportive care",        "Rest, fluids, small frequent feeds for infants; avoid cough suppressants in infants"],
        ["Hospitalization",        "Required for infants with apnea, oxygen needs, or feeding difficulties"],
      ], ["Item", "Detail"]),

      subHeading("Vaccination Schedule"),
      twoColTable([
        ["DTaP (infants/children)", "5 doses: at 2, 4, 6 months; 15–18 months; 4–6 years"],
        ["Tdap (adolescents)",      "1 booster at age 11–12; then every 10 years"],
        ["Tdap in pregnancy",       "1 dose every pregnancy at 27–36 weeks — protects newborn before their own vaccines"],
        ["DTaP coverage (global)",  "85% of infants received ≥3 doses (DTP3) in 2024 — WHO"],
        ["Adult Tdap gap",          "Only ~31.7% coverage in US adults — major driver of adult-to-infant transmission"],
      ], ["Vaccine", "Details"]),

      subHeading("Public Health Programs"),
      bullet("WHO Expanded Programme on Immunization (EPI)", ""),
      subBullet("Global DTP vaccination initiative targeting infants in all countries"),
      bullet("Cocoon Strategy", ""),
      subBullet("Vaccinating parents, siblings, and caregivers to protect newborns before their vaccines"),
      bullet("Maternal Tdap", ""),
      subBullet("WHO and CDC recommend 1 dose per pregnancy — most effective strategy for protecting young infants"),
      bullet("Contact tracing", ""),
      subBullet("All household contacts given prophylactic antibiotics; 21-day symptom monitoring"),
      bullet("Gavi Vaccine Alliance", ""),
      subBullet("Funds DTP vaccines in 57 lower-income countries"),
      spacer(),

      // ── FIELD 7: QUICK FACTS ─────────────────────────────────
      sectionHeading("7.  QUICK FACTS / DID YOU KNOW?"),
      spacer(),
      bullet('Known as the "100-day cough" in Chinese medicine — coughing fits can last up to 3 months'),
      bullet("Despite >90% vaccination rates globally, pertussis CANNOT be eliminated because vaccine immunity wanes"),
      bullet("The 2024 global surge was 476% higher than 2023 — the largest post-COVID resurgence recorded"),
      bullet("Teens and adults are the hidden reservoir — they spread it to vulnerable infants while thinking they just have a bad cold"),
      bullet("For every 1 diagnosed adolescent/adult case, there are an estimated ~5 undetected cases"),
      bullet("The whooping sound is heard mainly in children — adults rarely whoop, making diagnosis much harder"),
      bullet("R₀ of 12–17 means one infected person can infect up to 17 others — as contagious as measles"),
      bullet("Reported cases (941,565 in 2024) represent only the tip of the iceberg — true burden estimated at ~24.1 million/year"),
      spacer(),

      // ── FIELD 8: SOURCES ─────────────────────────────────────
      sectionHeading("8.  SOURCES"),
      spacer(),
      new Paragraph({
        spacing: { before: 60, after: 60 },
        children: [new TextRun({ text: "1.  WHO Immunization Coverage Fact Sheet (2025). who.int/news-room/fact-sheets/detail/immunization-coverage", size: 18, font: "Calibri", color: DARKGRAY })],
      }),
      new Paragraph({
        spacing: { before: 60, after: 60 },
        children: [new TextRun({ text: "2.  CDC — 2024 Provisional Pertussis Surveillance Report (January 2025). cdc.gov/pertussis", size: 18, font: "Calibri", color: DARKGRAY })],
      }),
      new Paragraph({
        spacing: { before: 60, after: 60 },
        children: [new TextRun({ text: "3.  CDC — Pertussis in Other Countries. cdc.gov/pertussis/php/global/index.html", size: 18, font: "Calibri", color: DARKGRAY })],
      }),
      new Paragraph({
        spacing: { before: 60, after: 60 },
        children: [new TextRun({ text: "4.  CDC Pink Book — Chapter 16: Pertussis. cdc.gov/pinkbook/hcp/table-of-contents/chapter-16-pertussis.html", size: 18, font: "Calibri", color: DARKGRAY })],
      }),
      new Paragraph({
        spacing: { before: 60, after: 60 },
        children: [new TextRun({ text: "5.  ECDC — Pertussis Annual Epidemiological Report for 2024. ecdc.europa.eu", size: 18, font: "Calibri", color: DARKGRAY })],
      }),
      new Paragraph({
        spacing: { before: 60, after: 60 },
        children: [new TextRun({ text: "6.  StatPearls/NCBI — Pertussis (updated 2024). ncbi.nlm.nih.gov/books/NBK519008", size: 18, font: "Calibri", color: DARKGRAY })],
      }),
      new Paragraph({
        spacing: { before: 60, after: 60 },
        children: [new TextRun({ text: "7.  PMC — Resurgence of pertussis: Epidemiological trends, contributing factors (2025). pmc.ncbi.nlm.nih.gov/articles/PMC12153400", size: 18, font: "Calibri", color: DARKGRAY })],
      }),
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        children: [new TextRun({ text: "8.  MDPI Vaccines — Routine DTP Vaccination Coverage and Herd Immunity Against Pertussis in 2024. mdpi.com/2076-393X/14/3/264", size: 18, font: "Calibri", color: DARKGRAY })],
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