**Question:** A 22-year-old male named Kallu developed fever, diarrhoea, and vomiting after eating chicken salad from a common restaurant with two of his friends. Two of his friends also experienced similar symptoms. What is the diagnosis?

**Core Concept:** Outbreak of gastrointestinal illness due to contaminated food or water, affecting multiple individuals.

**Why the Correct Answer is Right:**
The correct answer is **D. Food Poisoning** because the symptoms described (fever, diarrhoea, and vomiting) are consistent with an infectious gastrointestinal illness. In this case, the common food item consumed by all three individuals (chicken salad) is the likely source of the illness. Food poisoning can occur when contaminated food or water is ingested, causing an infection or toxin-induced illness.

**Why Each Wrong Option is Incorrect:**
A. **Infectious Gastroenteritis:** This answer choice is incorrect because the symptoms are not specific to a single infectious agent, like viral, bacterial, or parasitic infections.

B. **Diarrhoeal Disorders:** While diarrhoea is a symptom mentioned, the other symptoms are not adequately addressed, and the correct answer should encompass the entire set of symptoms.

C. **Viral Gastroenteritis:** This answer choice is incorrect because viral gastroenteritis typically presents with a broader range of symptoms, including abdominal pain, nausea, and sometimes abdominal cramps. It also typically has a more acute onset and a shorter duration compared to the described case.

**Clinical Pearl:**
Food poisoning is a common cause of gastrointestinal illness, especially in outbreaks involving shared meals. Such outbreaks can occur due to inadequate food handling, storage, or preparation practices, causing infections from bacteria, viruses, or parasites.

**Correct Answer:** **D. Food Poisoning**

**Explanation:**
The correct answer is food poisoning, which can result from consuming contaminated food or water that has caused infection or toxin-induced illness. In this scenario, the common meal shared among Kallu and his friends likely led to the gastrointestinal symptoms described (fever, diarrhoea, vomiting) due to the consumption of contaminated chicken salad from the same restaurant.

**Why Each Wrong Option is Incorrect:**
A. Infectious Gastroenteritis: This answer does not address the fever and vomiting symptoms.

B. Diarrhoeal Disorders: While diarrhoea is mentioned, the other symptoms, including fever and vomiting, are not adequately explained.

C. Viral Gastroenteritis: This answer type typically presents with a more abrupt onset, abdominal pain, and sometimes abdominal cramps. The described case demonstrates a more gradual onset and does not include abdominal pain or cramps.

**Clinical Pearls:**
1. Food poisoning outbreaks can occur due to poor food handling, storage, or preparation practices that result in infections from bacteria, viruses, or parasites.
2. Sharing meals in such outbreaks can lead to similar gastrointestinal symptoms among those consuming the contaminated food item, in this case, the chicken salad from the same restaurant.