Health reviews

Plain-language, citation-grounded reviews of 69 diseases — from the general public to the science. Pick a topic and dig as deep as you like.

Infectious disease 13

Chagas disease: twenty silent years, then a heart problem 63 refs

A neglected parasitic infection that does almost nothing for decades and then destroys the heart.

Dengue: four viruses, one mosquito, and a curve with a peak in it 100 refs

A public-to-science account of dengue: the four serotypes and antibody-dependent enhancement, NS1 and serostatus testing, WHO warning signs and the plasma-leak window, the Dengvaxia cautionary tale…

H5N1 avian influenza: a bird virus at a barrier it has not crossed 64 refs

The pandemic-preparedness case study, explained without alarm: why H5N1 is a bird virus that infects people only sporadically, what the species barrier is actually made of (receptor binding, airway…

HIV: a fatal diagnosis that became a chronic condition, and a treatment that is also prevention 56 refs

One of the largest reversals in the history of medicine, and the mechanism behind it.

Lyme disease: a curable infection with a difficult diagnosis and a contested aftermath 60 refs

The tick-borne infection that is reliably cured early and hardest to test for at exactly that moment: why erythema migrans in an endemic area needs no blood test (only about a third of such patients…

Malaria: a parasite, a mosquito, and a number called R0 96 refs

A public-to-science account of Plasmodium: the two-host life cycle, microscopy and HRP2 rapid tests and how parasites evade them, ACTs and the artemisinin resistance now reaching Africa, the first…

Measles: the virus that finds every gap 70 refs

A public-to-science account of the most contagious human infection: immune amnesia that deletes years of accumulated immune memory, IgM and genotyping in an elimination setting, vitamin A as the one…

Pneumonia: the alveoli fill up, and five bedside variables decide where you are treated 193 refs

A leading infectious killer — 2.38 million lower-respiratory-infection deaths in 2016, with S.

Schistosomiasis: a worm that needs a snail, a pond, and a mate 61 refs

The archetypal neglected tropical disease, and an unusually elegant one.

Tuberculosis: a quarter of humanity is infected, and almost none of them are ill 112 refs

A public-to-science account of TB: the latent-versus-active distinction and the 1.7-billion-person reservoir, Xpert and the limits of IGRA, the six-month regimen and why it must be that long, BPaLM…

Urinary tract infection: a simple infection with two hard problems 112 refs

One of the commonest bacterial infections — 10.8% of US women report one a year, a third have had one by age 24 — and easy to treat, which is why the review is about the two things that are not…

Valley fever: a fungus in the dust, and a map that keeps growing 65 refs

A public-to-science account of coccidioidomycosis: the dimorphic life cycle that makes it airborne, complement-fixation titres as a severity marker, why most cases need no antifungal while…

Viral hepatitis B and C: one vaccine-preventable, one curable, both silent for decades 41 refs

Two unrelated viruses causing 57% of the world's cirrhosis and 78% of its liver cancer, with opposite shapes: hepatitis B is prevented by the first vaccine shown to stop a human cancer but…

Cancer 6

Breast cancer: not one disease, and the argument about finding it early 77 refs

A public-to-science account of breast cancer: the molecular subtypes that decide everything, mammographic screening quantified on both sides (20% mortality reduction against 11-19% overdiagnosis), a…

Colorectal cancer: a slow-growing cancer we can catch before it starts 89 refs

A public-to-science walkthrough of screening and the adenoma-carcinoma sequence, TNM staging and molecular markers, stage-directed therapy, and a tumour-growth model of the detection window.

Lung cancer: the most preventable common cancer, and the most transformed 43 refs

The leading cause of cancer death, and the one with two interventions that actually work.

Melanoma: the cancer where depth decides, and where immunotherapy arrived first 83 refs

The dangerous skin cancer, because it can spread while still small — and the disease that proved checkpoint blockade before it was exported to lung, kidney and bladder.

Pancreatic cancer: a disease of stage, not of biology 70 refs

One of the deadliest common cancers — overall five-year survival around 9% — but that average hides the structure: stage IA disease reached 83.7% five-year survival, and metastasis happens late in…

Prostate cancer: the hard problem is telling harmless from lethal 50 refs

The most common non-skin cancer in men, and the clearest case in oncology of detection and benefit coming apart.

Heart & vascular 4

Atrial fibrillation: an irregular rhythm, the clot it makes, and two decisions that are made separately 165 refs

The commonest sustained arrhythmia and, in the very old, the cause of more than a third of strokes — 36.2% at ages 80–89 in Framingham, and the one cardiac risk factor whose stroke effect does not…

Coronary artery disease: the world's leading cause of death, and the two clocks that decide its outcome 322 refs

The #1 killer worldwide, organised around two clocks: the decades-long one that decides whether you get atherosclerosis, and the minutes-long one that decides how much heart muscle you keep once a…

Heart failure: a pump on a flat curve, and the four drugs that lift it 89 refs

A public-to-science account of heart failure as a syndrome: the ejection-fraction categories and natriuretic peptides, a Frank-Starling model whose failing curve is flat, the four pillars of HFrEF…

Hypertension: high blood pressure, why it matters, and how it is managed 19 refs

A front-door public explanation of BP phenotypes, measurements, and medications, with a Windkessel-style pressure-control model.

Brain & nerves 8

ALS: a straight line down, and what it takes to bend it 77 refs

The archetypal motor-neuron disease: upper and lower motor neurons lost, spread across body regions, respiratory failure in two to five years — and cognition less spared than the standard…

Alzheimer disease: memory, biomarkers, and where therapy is moving 27 refs

A public-to-science walkthrough of diagnosis, measurement layers, and therapy progress, with biomarker-first workflows and frontier-stage treatment architecture.

Epilepsy: two drugs decide it, and most people stop there 49 refs

A common neurological disease that is not one disease, and whose treatment response has a decisive shape: nearly two-thirds become seizure-free, but 50.5% on the first drug, 11.6% on the second and…

Huntington's disease: a number you inherit, and the first attempts to change it 83 refs

A public-to-science account of the CAG repeat: how a count becomes a diagnosis and where its grey zones are, why repeat length explains only half of onset age, somatic instability as the other half…

Migraine: not a headache, and now it has its own drugs 58 refs

A disorder of sensory processing rather than a bad headache, and the first condition in neurology to get drugs designed for it after CGRP infusion was shown to cause migraine rather than merely…

Multiple sclerosis: an immune attack on wiring insulation, and the case for treating early 42 refs

An immune-mediated disease whose cause now appears largely identified — a cohort of over 10 million found MS risk rose 32-fold after Epstein-Barr infection and after no other virus.

Parkinson's disease: five silent years, then a movement disorder 73 refs

Completes the neurodegeneration set.

Stroke: a clock, a clot, and the brain you can still save 89 refs

A public-to-science account of ischemic stroke: core versus salvageable penumbra, FAST and NIHSS and the three imaging questions, thrombolysis and thrombectomy and how their benefit decays with…

Mental health 3

Anxiety disorders: fear out of proportion, and treatments that work about as well as each other 134 refs

Among the commonest mental-health conditions — 7.3% current global prevalence, median onset age 11, and 41% of primary-care patients with an anxiety disorder receiving no treatment at all.

Bipolar disorder: the highs decide the diagnosis, the lows dominate the illness 131 refs

The mood disorder most often mistaken for unipolar depression — in a community screen, more people with a positive bipolar screen had been told they had unipolar depression (31.2%) than bipolar…

Depression: what the numbers actually say 44 refs

A public-to-science account of major depressive disorder written for honesty about effect sizes: no biomarker and what rating scales do and do not capture, the PHQ-9's 5-point minimal clinically…

Hormones & metabolism 6

Diabetes and the HbA1c biomarker: from average glucose to glycemic control 29 refs

A plain-language guide through measurements, medicines, and progress with a public-to-science path to the HbA1c model.

Gout: a solubility problem, and the number that solves it 51 refs

The most common inflammatory arthritis, and almost the only curable one: urate crystallises above a solubility threshold, and holding serum urate below it dissolves the deposits and stops the attacks.

Obesity: why weight biology matters and how treatment is evolving 27 refs

A measurement-first, mechanism-aware review of phenotype, treatment classes, and durable control with a simple energy-balance model.

Polycystic ovary syndrome: a reproductive diagnosis with a metabolic engine 57 refs

The most common endocrine disorder in women of reproductive age, and badly named: it is not about cysts but about irregular ovulation, androgen excess, and the insulin resistance underneath both —…

Thyroid disease: one blood test screens an entire axis, and here is why 55 refs

Hypo- and hyperthyroidism, mostly autoimmune, and the control-systems reason a single TSH measurement screens the whole pituitary-thyroid axis: the feedback is log-linear, so a 10 pmol/L move in…

Type 1 diabetes: an autoimmune disease with a measurable presymptomatic phase 150 refs

Not a variant of type 2 — the immune system destroys the beta cells, so there is no insulin to sensitise anyone to, and replacement is what keeps the person alive.

Lungs & breathing 3

Asthma: the obstruction that comes back, and the inhaler that isn't a rescue 51 refs

A public-to-science account of asthma: reversibility as the diagnostic signature and how it differs from COPD's fixed obstruction, FeNO and eosinophils as phenotyping biomarkers, an…

COPD: a slope you can bend but not rewind 81 refs

A public-to-science account of airflow obstruction: the post-bronchodilator FEV1/FVC threshold and how it contrasts with the restrictive dust diseases, the Fletcher-Peto decline model and what…

Obstructive sleep apnea: a disease defined by a count, treated by a device that has to be worn 51 refs

Opens the sleep domain: roughly a billion adults affected and most undiagnosed, the apnea-hypopnea index and why a count is a crude severity measure, the sympathetic surge behind the cardiovascular…

Kidney & urinary 4

Benign prostatic hyperplasia: the same organ, the other disease 65 refs

Not prostate cancer, and not a precursor of it — hyperplasia grows in the transition zone where it obstructs, malignancy in the peripheral zone where it does not.

Chronic kidney disease: a quiet loss of filtration, and how it is slowed 71 refs

A public-to-science walkthrough of eGFR and albuminuria staging, three eras of kidney-protective drugs, and a linear eGFR-slope model of time to kidney failure.

CKDu: kidney failure in young workers who have none of the usual causes 112 refs

A public-to-science account of chronic kidney disease of non-traditional cause and Mesoamerican nephropathy: diagnosis by exclusion, the cross-shift and cross-harvest eGFR declines that broke the…

Kidney stones: a solubility problem with a very simple lever 64 refs

Common, intensely painful and highly recurrent — 53% within eight years of a first stone — but at bottom a physical-chemistry problem.

Digestive & liver 3

Fatty liver disease: a third of adults have it, and the stage is what matters 36 refs

A public-to-science account of MASLD and MASH, including why the field renamed them from NAFLD/NASH: the steatosis-to-fibrosis ladder, FIB-4 and elastography as triage, a Markov progression model…

Gallstones: cholesterol beyond what bile can dissolve 52 refs

The third supersaturation disease, after gout and kidney stones — and it shares their twist: normal bile is routinely supersaturated with cholesterol and forms no stones.

GERD: a common nuisance, a very large drug class, and a small dangerous tail 42 refs

Reflux affects up to a quarter of adults in North America and Europe, and proton-pump inhibitors are among the ten most-used drugs on earth.

Autoimmune & rheumatology 5

Celiac disease: a known trigger, a measurable antibody, and a test that means different things to different people 81 refs

An autoimmune enteropathy — not an allergy, not an intolerance — affecting about 1%, with most cases undiagnosed: of 35 found in a national survey, 29 did not know.

Inflammatory bowel disease: treating what the camera sees, not what the patient feels 40 refs

Crohn's disease and ulcerative colitis, and the shift that reorganised their management: from treating symptoms to treating the mucosa.

Osteoarthritis: the X-ray and the patient are measuring different things 60 refs

The most common joint disease, affecting 240 million people — and not “wear and tear”: prevalence has doubled since the mid-20th century by 2.1-fold even after controlling for age and BMI, so it is…

Psoriasis: the disease that got its mechanism drugged 46 refs

A systemic immune-mediated disease, not a cosmetic one, and the clearest case of a pathway being mapped and then deliberately targeted: dendritic cells make IL-23, IL-23 sustains Th17 cells, Th17…

Rheumatoid arthritis: an autoimmune disease that stopped destroying joints 42 refs

A public-to-science account of RA, opening the autoimmune domain: why it is immune rather than wear-and-tear, autoantibodies detectable a median of 4.5 years before symptoms, DAS28 and the…

Blood 2

Iron-deficiency anaemia: a finding, not a diagnosis 50 refs

The commonest nutritional deficiency on earth — WHO puts anaemia at 24.8% globally, 1.62 billion people — and a condition where the decisive move is finding why, since iron is lost only by bleeding.

Sickle cell disease: one letter of DNA, and the first CRISPR cure 91 refs

A public-to-science account of how a single beta-globin substitution polymerizes haemoglobin, the delay-time race that unifies every therapy, the balancing-selection model that explains why the…

Eyes 3

Cataract: the blindness that surgery undoes 72 refs

The leading cause of blindness worldwide — and the hopeful one, because a twenty-minute operation gives the sight back.

Glaucoma: the one lever we can pull 66 refs

The leading cause of irreversible blindness, and silent while it does the damage — half the people with optic-nerve damage in a 5,308-person survey did not know.

Macular degeneration: two diseases under one name 53 refs

The leading cause of central vision loss in older adults — the exact inverse of glaucoma, which takes the periphery first.

Skin 1

Atopic dermatitis: a leaky barrier and an immune system that overreacts to what gets in 80 refs

Eczema, where the itch is the disease and the rash is largely what scratching does.

Bones, joints & muscle 1

Osteoporosis: a silent disease diagnosed by a line drawn on a smooth curve 44 refs

A public-to-science account of osteoporosis, opening the musculoskeletal domain: bone remodelling and why loss is silent, the T-score and why it is a convention rather than a boundary, a model…

Reproductive health 1

Endometriosis: the disease that takes seven years to name 90 refs

A common cause of pelvic pain and infertility whose defining problem is recognition, not biology: six studies across eight countries and twenty years put the interval from first symptom to diagnosis…

Ear, nose & throat 1

Hearing loss: the commonest sensory disorder, and the one people wait longest to treat 157 refs

One person in five on Earth — 1.57 billion — has hearing loss, and the Global Burden of Disease study reports the moderate-or-worse count twice in one sentence, adjusted and unadjusted for hearing…

Occupational & environmental 2

Black lung: an old disease that came back, and why silica is the reason 56 refs

A public-to-science account of coal workers' pneumoconiosis: ILO radiographic grading and the simple-CWP/PMF divide, why management is prevention rather than cure, a cumulative-exposure risk model…

Silicosis: the oldest occupational lung disease, back in a kitchen countertop 95 refs

A public-to-science account of respirable crystalline silica: ILO grading and the accelerated/acute forms, why management is prevention rather than cure, a zero-free-parameter dose-response model…

Genetic 2

Cystic fibrosis: one broken channel, and the drugs that learned to fold it 47 refs

A public-to-science account of CF: newborn screening and the sweat chloride test as a quantitative CFTR-function readout, mutation classes and why they decide drug eligibility, a zero-free-parameter…

Hemochromatosis: the commonest genetic disease most people have never heard of, treated by bloodletting 36 refs

A lesser-known disease with a startlingly simple cure: inherited over-absorption of dietary iron that silently loads the liver, heart, pancreas and joints.

Critical care 1

Sepsis: when the response to an infection becomes the thing that kills you 41 refs

A public-to-science account of sepsis: the Sepsis-3 definition and why it retired 'severe sepsis', where qSOFA works and where it does not, lactate and source control, the time-to-antibiotic…