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NDA Biology · Microbiology and Disease

Disease Vectors — Malaria

A vector is the carrier that moves a pathogen from host to host; for malaria the vector is the female Anopheles mosquito, while the pathogen it carries is the protozoan Plasmodium.

Why this matters

The vector-vs-pathogen distinction is exactly the kind of fact the NDA loves to blur. Malaria's vector question has appeared (2025) and is a guaranteed mark if you keep two things straight: it is the FEMALE mosquito (she needs a blood meal for her eggs) and it is the ANOPHELES species (not Culex or Aedes). Learn the mosquito-to-disease map alongside it — Anopheles : malaria, Aedes : dengue, Culex : filariasis.

Concept 1 of 1: The malaria vector — female Anopheles

Two different organisms are involved in malaria: the mosquito that carries it (the VECTOR) and the parasite that causes the fever (the PATHOGEN). The vector is the female Anopheles mosquito; the pathogen is Plasmodium. Only the female bites for blood — she needs the protein to mature her eggs — so only the female transmits the parasite.

Definition

The vector-vs-pathogen split for malaria, plus the mosquito-to-disease map:

  • Vector: the female Anopheles mosquito — the carrier. (The male feeds on nectar and never bites, so it cannot transmit.)
  • Pathogen: Plasmodium — a protozoan parasite that multiplies in the human liver, then in red blood cells.
  • Other mosquito vectors: Aedes carries dengue and chikungunya; Culex carries filariasis (elephantiasis) and Japanese encephalitis.
Female Anopheles(vector)Human bloodbittenLiverPlasmodium multipliesRed blood cellsparasite replicatesPlasmodium

Vector = the carrier (mosquito). Pathogen = the parasite (Plasmodium). The bank loves to swap them.

MosquitoDisease carriedNote
Female AnophelesMalariaOnly the FEMALE bites; pathogen = PlasmodiumQ
Vector = female Anopheles; pathogen = Plasmodium. Keep the two distinct. NDA 2025.
AedesDengue, chikungunya, ZikaDaytime biter; tiger-striped legs
CulexFilariasis, Japanese encephalitisCarries the elephantiasis worm Wuchereria
Anopheles → malaria, Aedes → dengue, Culex → filariasis. The vector carries; the pathogen causes.
Practice this conceptself-check · 4 quick reps

The same idea in a real exam question:

NDA · Apr 2025 · Q113Easy

Example 1 · Microbiology and Disease · Disease Vectors — Malaria

The vector of malaria parasites is

It's the FEMALE Anopheles, not the male

Only the female mosquito bites — she needs a blood meal to develop her eggs. The male feeds on plant nectar and never transmits disease. Distractors offer 'male Anopheles' and 'female Culex'; the answer is female Anopheles.

Vector ≠ pathogen

The mosquito is the vector (carrier); Plasmodium is the pathogen (cause). A question asking 'what causes malaria?' wants Plasmodium; one asking 'what is the vector?' wants the female Anopheles. Read which one is asked.

Summary — formulas & gotchas at a glance

A revision cheat-sheet for the formulas and gotchas above. Click any concept name to jump back to its full explanation.

Reference tables (1)

The malaria vector — female Anopheles3 rows
MosquitoDisease carriedNote
Female AnophelesMalariaOnly the FEMALE bites; pathogen = PlasmodiumQ
Vector = female Anopheles; pathogen = Plasmodium. Keep the two distinct. NDA 2025.
AedesDengue, chikungunya, ZikaDaytime biter; tiger-striped legs
CulexFilariasis, Japanese encephalitisCarries the elephantiasis worm Wuchereria
Anopheles → malaria, Aedes → dengue, Culex → filariasis. The vector carries; the pathogen causes.

Watch out for (2)

Test yourself on Microbiology and Disease

10 past NDA questions from this chapter, timed at 10 minutes and marked the way the exam marks it. You see your score and every answer the moment you finish. Free to start.