Shingles caused by varicella-zoster was regarded as rare disease, mostly related to childhood chickenpox. However, meningoencephalitis caused by varicella-zoster is increasingly recognized as a predominant cause of ME among immunocompetent adults in non-epidemic circumstances. Diagnosis of complications of varicella-zoster, particularly in cases where the disease reactivates after years or decades of latency, are difficult. A rash (shingles) can be present or absent. Symptoms vary, and there is significant overlap in symptoms with herpes-simplex symptoms. Although DNA analysis techniques such as polymerase chain reaction (PCR) can be used to look for DNA of herpesviruses in spinal fluid or blood, the results may
Chronic obstructive pulmonary disease Chronic obstructive pulmonary disease Chronic obstructive pulmonary disease (COPD) is a type of obstructive lung disease characterized by long-term breathing problems and poor airflow. The main symptoms include shortness of breath and cough with sputum production. COPD is a progressive disease, meaning it typically worsens over time. Eventually everyday activities, such as walking or getting dressed, become difficult. Chronic bronchitis and emphysema are older terms used for different types of COPD. The term "chronic bronchitis" is still used to define a productive cough that is present for at least three months each year for two years. Tobacco smoking is the