Infectious Diseases
Dengue Fever
Most dengue is survived at home. The danger opens on days three to seven, usually as the fever falls. These are the warning signs that mean hospital now.
28 Aug 202614 min read
White blood cell
Also known as Leucocyte, WBC, TLC
White blood cells are the immune system's cells in the bloodstream, and their job is fighting infection. The count and the mix of types are reported in a full blood count.
White cells are a family rather than a single cell type, and the proportions carry the information. A reports a total and then a differential — the breakdown by type — and it is usually the differential that indicates what kind of process is underway.
| Type | Main role | Typically raised in |
|---|---|---|
| Neutrophil | First responder to bacteria | Bacterial infection, |
| Lymphocyte | Targeted response, production | Viral infection |
| Eosinophil | Parasites and allergy | Allergy, asthma, worm infestation |
| Monocyte | Clearing debris, chronic infection | Longer-standing infection |
A raised total count usually signals infection or inflammation, but not always: treatment, stress and smoking all raise it. A low count matters in the other direction — it leaves a person vulnerable, and it is watched carefully during chemotherapy and in some infections.
Where this comes up
General Medicine
Fever in Adults: What It Means and When to Worry
Most fevers settle within three days. In Pakistan a fever that lasts longer needs testing for dengue, typhoid or malaria — and a few need help the same hour.
27 Aug 20269 min read
Infectious Diseases
Typhoid Fever
A fever that climbs day by day for a week, with headache and belly pain. Why the Widal test misleads, and what drug-resistant typhoid changes here.
11 Aug 202611 min read
Related terms
- Complete blood countCBC, Full blood countA complete blood count measures the three families of cell in blood: red cells that carry oxygen, white cells that fight infection, and platelets that clot. It is the commonest blood test ordered anywhere and the usual first step in tiredness, fever, bruising or bleeding.
- PlateletThrombocyte, PLTPlatelets are the smallest cells in blood and their job is clotting — they clump at the site of an injury and form the initial plug that stops bleeding. A platelet count is part of a standard blood test.
- HaemoglobinHemoglobin, HbHaemoglobin is the iron-containing protein inside red blood cells that binds oxygen in the lungs and releases it to the tissues. Its concentration in blood is the number used to diagnose anaemia.
- BacteriaBacterium, GermsBacteria are single-celled living organisms, most of them harmless or useful, a minority of which cause infection. Unlike viruses they can be killed by antibiotics, which is the whole reason the distinction matters at the point of treatment.
- VirusViral infectionA virus is genetic material in a protein coat that can only reproduce inside a living cell. Antibiotics have no effect on viruses, which is why they are not prescribed for a common cold.
- SepsisBlood poisoning, SepticaemiaSepsis is the body's response to an infection turning against its own organs, and it is a medical emergency. It can develop from any infection and worsens by the hour without treatment.
- AntibodyImmunoglobulin, IgAn antibody is a protein made by the immune system that locks onto one specific target on a germ and marks it for destruction. Antibodies are what give a person lasting protection after an infection or a vaccination.
- InflammationSwelling, SozishInflammation is the body's response to injury or infection: blood flow increases, fluid and immune cells arrive, and the area becomes red, warm, swollen and painful. It is a repair process, and it becomes a problem only when it persists.