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Vaccine-Preventable Disease

Valvular Heart Disease

Vascular dementia

Vascular dementia is a type of dementia caused by reduced blood flow to the brain, which can deprive brain cells of the oxygen and nutrients they need to function properly. This can happen due to blood vessel blockage or damage, leading to strokes or smaller brain injuries over time, which gradually affect thinking, reasoning, and memory capabilities. Vascular dementia is considered the second most common cause of dementia after Alzheimer's disease, and its symptoms can vary widely depending on the areas of the brain affected and the severity of the blood flow disruption. Symptoms often include confusion, difficulty focusing, trouble organizing thoughts or tasks, and problems with memory. Unlike Alzheimer's, which usually begins with memory problems, vascular dementia may start with impaired judgment or the inability to plan. Physical symptoms, such as difficulty walking or a sudden weakness on one side of the body, can also occur, reflecting the brain regions affected by poor blood flow or strokes.

Vasculitides

Vasculitides represents a complex group of health conditions characterized by the inflammation of blood vessels, a process that can lead to significant organ and tissue damage. This umbrella term encompasses various disorders, each affecting different sizes and types of vessels, ranging from large arteries to small capillaries. The inflammation in vasculitides narrows the blood vessels, reducing blood flow and potentially leading to tissue ischemia or necrosis. Symptoms: The symptoms and severity of vasculitides vary widely, depending on the specific vessels and organs involved. Common symptoms include fever, fatigue, weight loss, muscle and joint pain, and in some cases, organ-specific manifestations such as kidney dysfunction, lung problems, or skin rashes. The etiology of vasculitides is multifaceted, often involving a combination of genetic predisposition and environmental triggers, such as infections or drugs, which provoke an aberrant immune response.

Venous thromboembolism (VTE)

Venous thromboembolism (VTE) is a serious health condition that encompasses two related disorders: deep vein thrombosis (DVT) and pulmonary embolism (PE). DVT occurs when a blood clot forms in a deep vein, usually in the legs, which can cause pain, swelling, and redness in the affected area. If a part of this clot breaks off and travels through the bloodstream to the lungs, it can lead to a pulmonary embolism—a life-threatening condition that can obstruct blood flow and oxygen, causing chest pain, shortness of breath, coughing (potentially with blood), and in severe cases, sudden death. Diagnosis of VTE involves a combination of medical history assessment, physical examination, and specialized tests. For DVT, ultrasound imaging is commonly used to visualize blood flow and detect clots in the veins. In suspected cases of PE, computed tomography pulmonary angiography (CTPA) is often the preferred diagnostic tool, as it provides detailed images of the blood vessels in the lungs.

Viral Hepatitis

Viral hepatitis is inflammation of the liver caused by one of several hepatitis viruses. The five main types — hepatitis A, B, C, D, and E — differ significantly in how they are transmitted, how long they last, and what treatment, if any, is needed. Some cause acute illness that resolves on its own; others can become chronic infections that persist for years and lead to serious liver complications if untreated. Viral hepatitis is among the most common causes of liver disease worldwide. Globally, hepatitis B and C account for the majority of chronic liver disease, cirrhosis, and hepatocellular carcinoma. Hepatitis A and E are primarily acute illnesses with fecal-oral transmission, while hepatitis D only occurs in people already infected with hepatitis B. Types of viral hepatitis Hepatitis A (HAV) A self-limiting acute infection transmitted through contaminated food or water. It does not cause chronic liver disease. Most people recover fully within two to three months, and infection confers lifelong immunity. A safe and effective vaccine is available.

Viral Infection

Viral Meningitis

Vitamin B12 Deficiency

Vitamin D Deficiency

Overview Vitamin D deficiency occurs when the body does not have enough vitamin D to support normal bone metabolism, muscle function, and immune regulation. Vitamin D is a fat-soluble vitamin that also acts as a hormone, helping the body absorb calcium and phosphorus and maintain skeletal strength. Because vitamin D is produced in the skin through sun exposure and is found in only a limited number of foods, deficiency is common worldwide—even in otherwise healthy individuals. Why Vitamin D Is Important Vitamin D plays a central role in multiple physiological systems, including: Calcium and phosphorus absorption Bone mineralization and skeletal integrity Muscle strength and coordination Immune system regulation Inflammatory control Low vitamin D levels can affect both short-term health (fatigue, muscle pain) and long-term outcomes (bone loss, fracture risk). Causes of Vitamin D Deficiency Vitamin D deficiency usually results from a combination of reduced production, inadequate intake, or impaired absorption.

Von Willebrand Disease