Ch15 quiz: Virus Infections: Respiratory and Skin

What virus causes the most common viral LRT disease in infants? What viral LRT disease is emerging from Asia?

.Paramyxovirus infections affect the lower respiratory tract. Paramyxoviruses include:Respiratory syncytial (RS) disease is caused by the respiratory syncytial virus (RSV).It commonly affects children under 1 year of age.Most common lower respiratory tract disease affecting infants and children; 200,000 deaths worldwide. Parainfluenza infections are usually caused by human parainfluenza viruses 1 and 3.Infections are milder than influenza.Human metapneumovirus (hMPV) are RSV-like viruses, but symptoms milder. Severe acute respiratory syndrome (SARS-CoV) spreads through close person-to-person contact. SARS is an emerging infectious disease; can produce pneumonia. It is spread by contact with an infected person or an object upon which they have coughed or sneezed. All SARS patients should be isolated for at least 10 days after fever has broken to prevent spread.

I want to identify a flu strain by a serological test. Which of these antibodies will best distinguish between H1N1 and H5N1? An antibody against: a) RNA; b) capsid protein; c) the protein "spikes" on the surface of the virus.

C)spikes Hemagglutinin (H) helps the virion attach and penetrate host cells. Neuraminidase (N) helps release virions from the host cell after replication and assembly. Each year a slightly different seasonal flu strain evolves, with genetic contributions from humans, birds, and pigs (mostly in Asia). Strains are named based on the gene segments encoding H and N e.g. "H1N1."

What virus causes both chickenpox and shingles? Why is chickenpox no longer as common as it was?

Chickenpox is no longer a prevalent disease in the United States. A vaccine using attenuated viruses became available in 1995. It is a highly communicable disease caused by the varicella-zoster virus (VZV). It is transmitted by skin contact and respiratory droplets. A red, itchy rash spreads across the entire body and turns into fluid-filled vesicles which break open and yield highly infectious virus-laden fluid. The most common complication is bacterial infection of the skin. Vaccination!Shingles is an adult disease caused by the same virus as chickenpox (varicella). After infection (such as chicken pox), VZV can remain in nerve cells for many years. Reactivated virus can travel to the body trunk and cause blisters and patches of red. It can also cause facial paralysis and severe "ice-pick" pains. It can occur repeatedly. Postherpetic neuralgia is the persistence of shingles pain for years after the blisters have disappeared. Zostavax is a vaccination to prevent Shingles

Who is in the greatest danger from rubella?

Congenital rubella occurs when the fetus is infected through the placenta. Children may be born with problems in the: eye, ear, heart Prevented by the MMR vaccine.

What strain of virus causes genital herpes? What 2 more serious diseases can it cause?

Genital herpes is a common STD, caused usually by HSV-2. Symptoms include:itching and throbbing in the genital area. followed by blisters.There is no cure, but antivirals can shorten and decrease the number of outbreaks.Infection of the eye is called herpes keratitis. It can cause scarring of the cornea and blindness. Neonatal herpes is a life-threatening disease passed from infected mothers to newborns during childbirth. The child's mental development can be delayed. Blindness and seizures can occur.

How do you know when an HSV infection is contagious? Can they be cured?

HSV infections are contagious whenever the blister or its remnants are present; NO

Herpes Skin diseases: 4 types. What variety of herpes virus causes cold sores? What 2 types of tissue/cells does it affect?

Human herpes simplex infections are widespread and often recurrent.Cold sores are contagious sores caused by HSV-1. After primary infection, the viruses become latent in sensory ganglia (nerve cells). Recurrence of cold sores occurs when viruses are reactivated and move to the epithelium (skin).

What cancer is caused by HHV-8, and who is most susceptible to it? Give 2 examples from this section of evidence for herpes virus latency (see question in Ch14 above).

Human herpesvirus 6 infections primarily occur in infancy. It causes roseola in infants, marked by: high fever. subsequent red rash. It is spread through contact with respiratory secretions or saliva. Many bone barrow transplant recipients suffer an HHV-6 viremia after transplantation. May potentially lead to pneumonia or encephalitis Kaposi sarcoma is an angiogenic tumor of the blood vessel walls. It is most commonly seen in immunocompromised individuals, such as AIDS patients. It is caused by HHV-8, forming dark or purple skin lesions. Aids, immunocompromised

Lower Respiratory Tract: 4 types. Is influenza dangerous? If we have a flu pandemic, what does that mean about its spread?

Influenza is a highly communicable acute respiratory infection. It is transmitted by airborne respiratory droplets. There have been at least 31 influenza pandemics since 1510. Flu is NOT a harmless disease: each year, 23,000 people in the U.S. die from pneumonia after infection.An epidemic is an outbreak of disease that is larger than expected. A pandemic is an epidemic that crosses international boundaries; more widespread than an epidemic.

Chickenpox and measles have some similar symptoms. Can you name one symptom that's different? What symptom is usually associated with mumps? What serious complication can it have in males?

Mumps (infectious parotitis) is characterized by enlarged jaw tissues caused by swollen salivary glands. The swelling is caused by blockage of ducts leading from the parotid glands. It is spread by respiratory droplets or contact with contaminated objects. In males, swelling and damage may occur in the testes (orchitis). Prevented by MMR vaccine Rubella (German Measles) is an acute, mildly infectious disease. It is transmitted by respiratory droplets or contact. Symptoms of rubella include an occasional fever and pale-pink maculopapular rash. Recovery is usually prompt, but relapses can occur.

Other viral skin diseases: 3 types. What do the letters in the "MMR" vaccine stand for?

Paramyxovirus infections can cause typical childhood diseases. Measles (rubeola) is a highly contagious disease Transmission occurs through respiratory droplets; patients have cough, feverKoplik spots are red patches with white grain-like centers that appear along the gum line. The characteristic red rash Vaccine is given in the MMR inoculation. Complications can be subacute sclerosing panencepalitis or Paget's disease of the bone measles, mumps, and rubella

What virus causes smallpox? Are there any known cases of smallpox disease in the world now?

Poxvirus infections have had great medical impacts on populations. Smallpox (variola) is contagious, and sometimes fatal. Pink-red macules appear on the face and trunk. They then become papules, and fluid-filled vesicles. The vesicles become pustules that break open and emit pus, leaving pitted scars (pocks). Smallpox disease was declared eradicated in 1972. Vaccinations ceased after that time, so many people are not immune. Smallpox virus still exists in storage, and is one of the most dangerous weapons of bioterrorism

What human population group drives flu outbreaks? Why should you not give aspirin to kids with a viral disease?

Preschoolers, Guillain-Barre syndrome damages nerves Reye syndrome from kids using aspirin (do not use aspirin in children with viral diseases!)

Where is Hantavirus found in the U.S., and what is its natural animal reservoir? Of all the LRT viruses, which has an available vaccine? What practice will help you avoid most of the others?

Reservoir is a deer mouse, virus shed in saliva, urine and feces. 1-5 weeks after exposure symptoms of fatigue, fever and muscle aches begin.Can lead to respiratory failure as lungs fill with fluid Found in the desert SW in wet years. Prevented by eliminating rodent nests

Upper Respiratory Tract: What 2 types of virus can cause the common cold? How are they transmitted? In general, should antibiotics be prescribed for them?

Rhinovirus + Adenovirus by airborne res. droplets; NO Rhinovirus infections are the chief cause of the common cold. Thrive in the lower temperature of the nose (33oC) They are transmitted by airborne respiratory droplets or contact with contaminated objects.Rhinoviruses are responsible for 30-50% of the cases of the common cold. More than 200 different virus strains can cause common colds. Researchers are studying the genome sequences for more than 100 rhinoviruses, and have found common genes to possibly develop a vaccine. Antibiotics do not affect viral diseases, including colds; incorrect use fosters resistant bacteria. Hand washing is the best defense against colds & flu.

Human Papilloma Virus: what 2 kinds of warts can it cause? What more serious complication can it cause in women? How can the chances of getting this complication be reduced?

Some Human Papillomavirus infections cause warts. Common warts are usually benign skin growths resulting from a strain of HPV. Plantar warts are on the soles of the feet. They can be transmitted by contact with: an affected person. a contaminated object. Genital warts (condylomata) are often transmitted through sexual contact. Some strains of HPV are associated with cervical cancer. They may be transmitted to newborns during delivery. There is a new vaccine (Gardasil) for some strains.

What is the host range of the influenza virus? Why must we have a new vaccine made every year? Rate Influenza groups A, B, and C in order of prominence in epidemics.

birds,pigs, people. Influenza A strikes every year and causes most epidemics.Influenza B also strikes every year but is less common than type A.Influenza C causes a mild respiratory illness but not epidemics.A new flu strain evolves every year, requiring development of a new vaccine - a mixture of the most common type A and B subtypes. Vaccination is about 75% effective Drugs including Tamiflu can help soon after infection The influenza genome consists of 8 RNA segments that can easily recombine between viruses

Both can cause laryngitis, which is infection of the _______. Which can cause acute febrile pharyngitis? To what more dangerous lower respiratory condition can it progress?

larynx; Adenovirus; viral pneumonia Adenovirus infections also produce symptoms typical of a common cold. Some Adenoviruses are frequent causes of acute upper respiratory infections Infection can cause: acute febrile pharyngitis ("febrile" refers to fever). pharyngoconjunctival fever. acute respiratory disease (ARD) in military recruits (vaccine available) May progress to viral pneumonia. Cold viruses can also cause laryngitis (infection of the larynx)