Dr. Jonathan D Zellan MD

Influenza Influenza, also commonly called as the flu, is a highly contagious respiratory infection caused by viruses, particularly influenza A or influenza B. These viruses usually infect the throat, nose, and lungs. Although the flu causes mild symptoms in most people, it can also cause severe...

What is pulmonary tuberculosis?Pulmonary tuberculosis or (TB) indicates a contagious bacterial infection involving the lungs but can also spread to various parts of the human body.What are the symptoms of pulmonary tuberculosis?People suffering from this lung condition would commonly experience the...

Cold sores are inflamed fluid-filled blisters, which appear in clusters on and around the mouth or lips. They can be seen when a person has a weakened immune system during fever, cold, or any other disease. Usually, cold sores are not harmful and should heal on their own within two to four weeks...

The deadly coronavirus that began as a handful of infections in China and exponentially multiplied around the globe has become one of the largest news stories of the decade.With over 50 million cases of COVID-19 confirmed and over 1 million deaths, the world is struggling on how to contain the virus...

Discovered in the 1980s in Western and Central Africa, HIV is a virus and at the same time an infection. HIV stands for human immunodeficiency virus. It is a virus that gets into the bloodstream and slowly attacks the human immune system. The immune system is a naturally occurring system in the body...

How is Cholera Diagnosed?Cholera is an acute bacteria disease caused by a bacterium called Vibrio cholerae. Infection with the cholera bacteria can lead to severe vomiting and diarrhea and finally electrolyte loss or dehydration. If not treated, cholera can, in many cases, result in death.In order...