Disease Resources

Duchenne muscular dystrophy (DMD) is a rare, fatal neuromuscular genetic disease that occurs in approximately one in every 3,500 – 5,000 males worldwide.

DMD is caused by a change or mutation in the gene that encodes instructions for dystrophin. These changes in the genetic code may include large deletions (about 60-70 percent), large duplications (about 10 percent) or other small changes (about 15-30 percent).

Genetic testing is required to confirm the diagnosis and identify the disease-causing mutation in the dystrophin gene.


The role of dystrophin

Dystrophin is a protein that plays a key structural role in muscle fiber function. In healthy muscle, dystrophin interacts with other proteins at the cell membrane to stabilize and protect the cell during regular activity involving muscle contraction and relaxation.


Boys and young men with DMD produce little or no dystrophin in their muscle.


Without dystrophin, normal activity causes excessive damage to muscle cells, and they are ultimately replaced by fibrotic tissue and fat, leading to a progressive loss of function.

Note: Healthy and DMD muscle tissues analyzed by immunofluorescence using an anti-dystrophin antibody.

 
 
 

SIGNS AND SYMPTOMS

Symptoms of DMD usually appear in infants and toddlers. Affected children may experience developmental delays such as difficulty in walking, climbing stairs or standing from a sitting position. Boys with DMD often walk on their toes and have large calves, as well as use the Gowers Maneuver to stand from the floor.

As the disease progresses, muscle weakness in the lower limbs spreads to the arms, neck and other areas. Most patients require full-time use of a wheelchair in their early teens, and then progressively lose the ability to independently perform activities of daily living such as using the restroom, bathing and feeding.

Eventually, increasing difficulty in breathing due to respiratory muscle dysfunction requires ventilation support, and cardiac dysfunction can lead to heart failure. The condition is universally fatal, and patients usually succumb to the disease in their twenties.

 
 
 
 

Viral hemorrhagic fevers are severe and life-threatening illnesses caused by several families of viruses. Generally, these diseases involve multiple organ systems, and can damage the vascular system and impair the body’s ability to regulate itself. Symptoms often include bleeding as well as other serious complications.

MARBURG HEMORRHAGIC FEVER

Marburg hemorrhagic fever is a severe and potentially fatal disease in humans first recognized in 1967. It is caused by an RNA virus of the Filoviridae family endemic to Africa. The Marburg virus was classified as a Category A bioterrorism agent by the Centers for Disease Control and Prevention (CDC) and was designated a material threat to national security and public health by the U.S. Department of Homeland Security.

SIGNS AND SYMPTOMS

Onset of the disease is often sudden, and the symptoms include fever, chills, nausea, vomiting, chest pain and diarrhea. Increasingly severe symptoms may also include massive hemorrhaging and dysfunction of multiple organs. Marburg virus infection is often fatal, and available data suggests up to 80 to 90 percent of cases result in death. There are currently no treatments for Marburg virus infection beyond supportive care reflecting a critical gap in the U.S. Strategic National Stockpile and public health preparedness.

 
 
 
 

Influenza, also called the flu, is a contagious respiratory illness caused by influenza viruses that infect the nose, throat and lungs. It can cause mild to severe illness, and at times can lead to death.

Most experts believe that flu viruses spread mainly by droplets made when people with the flu cough, sneeze or talk. These droplets can land in the mouths or noses of people who are nearby. Less often, a person might also get flu by touching a surface or object that has flu virus on it and then touching their own mouth, eyes or possibly their nose.

Complications of flu can include bacterial pneumonia, ear infections, sinus infections, dehydration and worsening of chronic medical conditions, such as congestive heart failure, asthma or diabetes.

Flu viruses are known to frequently mutate and when a new strain emerges, a flu pandemic can rapidly occur if the human population has little to no immunity against it. In addition, variants of the flu virus naturally occur in other animals including wild aquatic birds (avian flu) and pigs (swine flu). While these viruses normally do not infect humans, there have been sporadic reports of humans being infected by variant strains of these viruses.

Given the limitations associated with currently available influenza antivirals and the potential for the rapid spread of new flu virus strains, an urgent need exists for broad-spectrum flu treatments.

SIGNS AND SYMPTOMS

Flu symptoms can vary by the strain, but may include a fever of 100 degrees Fahrenheit or higher, coughing, sore throat, a runny or stuffy nose, head and body aches, chills, fatigue, nausea, vomiting, and diarrhea. At times, the flu can lead to difficulty in breathing or shortness of breath, pain or pressure in the chest or abdomen, dizziness and seizures.