Aestivo-autumnal fever is malaria caused by

Options

A. Plasmodium ovale
B. P. malariae
C. P.vivax
D. P. falciparum.

Answer

**Step-by-Step Solution:**

1. **Understanding Malaria**: Malaria is a disease caused by protozoan parasites belonging to the genus *Plasmodium*. There are several species of *Plasmodium* that cause malaria in humans.

2. **Identifying the Species**: The main species of *Plasmodium* that cause malaria are:
- *Plasmodium vivax*
- *Plasmodium ovale*
- *Plasmodium malariae*
- *Plasmodium falciparum*

3. **Types of Malaria**: Malaria can be categorized into benign and malignant types:
- **Benign Malaria**: Caused by *Plasmodium ovale*, *Plasmodium malariae*, and *Plasmodium vivax*. These types are generally less severe and patients usually recover.
- **Malignant Malaria**: Caused by *Plasmodium falciparum*. This type is severe and can be fatal.

4. **Aestivo-Autumnal Fever**: The term "Aestivo-autumnal fever" refers specifically to the severe type of malaria that occurs in temperate climates, particularly during late summer and autumn. This fever is associated with the malignant form of malaria.

5. **Conclusion**: Based on the information, Aestivo-autumnal fever is caused by *Plasmodium falciparum*.

**Final Answer**: Aestivo-autumnal fever is malaria caused by *Plasmodium falciparum*.

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