General Infectious Disease Consulting
Influenza (flu) is a potentially life threatening illness. It is a contagious disease of the respiratory tract caused by influenza viruses. Each year, influenza causes serious infection and death around the globe, usually in the winter months (seasonal influenza).
Due to some pre-existing immunity to the seasonal strains of influenza, most people only suffer a self-limiting illness, lasting from a few days to several weeks. Influenza can lead to complications and for some people – the elderly, people with poor immune systems and people with pre-existing respiratory, cardiac and endocrine disease—influenza can be a significant disease and cause death. It can also cause the death of healthy adults and children.
Three different types of influenza viruses infect humans – types A, B and C. Only influenza A and B cause major outbreaks and severe disease. They are included in seasonal influenza vaccines. Influenza C causes a common cold-like illness in children. Only influenza A is known to have been responsible for influenza pandemics.
Influenza A and B viruses have two main proteins on the outside of the virus: the haemagglutinin (H); and the neuraminidase (N) proteins. These proteins are referred to as ‘antigens’ because they are the structures to which our immune system responds. New strains of influenza A and B continually emerge because of the tendency of these H and N antigens to change.
Of the influenza A viruses, only subtypes H1, H2 and H3 have been transmitted easily between humans. Only the H1 and H3 subtypes are currently circulating causing seasonal influenza in humans.
While influenza B is essentially a human disease, influenza A viruses are found in many species. Influenza A occurs as distinct forms or subtypes based principally on their haemagglutinin antigen, of which there are 16 different versions. Water birds are the natural host of influenza A viruses. From time to time influenza A viruses have, however, successfully jumped the species barrier and have become established in other animals, including humans.
Valley fever, also known as coccidioidomycosis, is a type of fungal infection caused by Coccidioides immitis. It enters the lungs when you inhale the fungus from soil in which it is present. This fungus is typically found in desert areas of the southwestern United States and parts of Central and South America. Your risk of acquiring valley fever increases if you are traveling to these destinations or if you have been receiving cancer treatment, have HIV or diabetes, have undergone an organ transplant or if you are pregnant.
Some people who contract valley fever have no symptoms, while others develop symptoms similar to a cold, the flu or even pneumonia. Symptoms, such as leg swelling, chest pain, coughing, fever, headaches, joint stiffness, loss of appetite and muscle aches, generally begin between five and 21 days after fungal exposure. If the infection spreads beyond the lungs to the bloodstream, skin, bones, lymph nodes or central nervous system, the patient may become very ill. Symptoms can include join swelling, severe lung difficulties, weight loss, change in mental function and sensitivity to light.
To diagnose valley fever, a chest X-ray, blood test and sputum culture may be performed. To determine whether the infection has spread, a biopsy, spinal tap or bronchoscopy is sometimes needed. Treatment for the milder form of the condition often revolves around bed rest and over-the-counter medication to relieve discomfort. In those with a compromised immune system, antifungal treatment is usually necessary. The most extreme cases may require surgery to remove the infected portion of the lung.
MRSA (Methicillin-Resistant Staphylococcus Aureus) infection, sometimes referred to as the “superbug,” occurs as a result of a staph infection that has become resistant to the antibiotics typically used to treat such infections. While MRSA most commonly affects people in healthcare-related environments, it can also affect healthy people, spreading through skin contact with an infected person.
As with most staph infections, the earliest symptom of MRSA is small red bumps appearing on the skin. If left untreated, these bumps can become painful, eventually requiring surgical drainage to clear the bacteria. To prevent life-threatening complications, seek medical attention for any persistent skin conditions, as they may be a sign of MRSA.
To diagnose MRSA, tissue samples and/or nasal secretions are studied in a microbiology lab to determine their resistance to antibiotics. Treatment for MRSA varies; some cases of MRSA may be treated with medications, while others may require surgical drainage of any abscesses on the skin. A personalized treatment plan will be developed based on each patient’s individual condition.