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„„Approved”
on methodical conference
department of infectious diseases and epidemiology
„____” ____________ 200 р.
Protocol № _____
Chief of Dept., professor __________ V.D. Moskaliuk
METHODOLOGICAL INSTRUCTIONS
to a fifth year student of the Faculty of Medicine
on independent preparation for practical training
Topic: ADENOVIRUS INFECTION. PARAINFLUENZA.
Subject:
Major:
Educational degree and qualification degree:
Year of study:
Hours:
Prepared by assistant professor
Topic: ADENOVIRAL INFECTION. PARAINFLUENZA
Infectious Diseases
Medicine
Specialist
5
2
Sydorchuk A.S.
1. Lesson duration: 2 hours
2. Aims of the lesson:
3.1. Students are to know:
• etiology of adenoviral and paragrippal infection, principal properties of viruses;
• adenoviral and paragrippal infection epidemiology;
• pathogenesis of adenoviral and paragrippal infection and morphology of organs afflicted by
virus;
• symptoms and development of typical and atypical adenoviral and paragrippal infection;
• clinical characteristic of croup stages;
• adenoviral and paragrippal infection complications;
• diagnosis of adenoviral and paragrippal infection;
• laboratory methods of examination at adenoviral and paragrippal infection;
• differential diagnosis of adenoviral and paragrippal infection including distinguishing
between similar diseases;
• treatment of adenoviral and paragrippal infection with taking into account of course severity;
• prophylactic and antiepidemic measures at adenoviral and paragrippal infection.
3.2. Students are to be able:
• to question a patient in order for obtaining of information on disease history and
epidemiologic anamnesis;
• to perform clinical examination of a patient;
• to formulate and to substantiate the diagnosis of adenoviral and paragrippal infection;
• to prepare a plan of additional patient examination;
• to evaluate results of laboratory examination;
• to determinate a form of disease;
• to make differential diagnosis to distinguish between similar diseases (flu, SARS, diphtheria,
etc.);
• to prescribe adequate pathogen and etiotropic treatment;
• to prepare a plan and organize prophylactic and antiepidemic measures.
3.3. Students are to acquire the following skills:
• to conduct clinical examination of a adenoviral and paragrippal infection patient and other
acute respiratory diseases;
• to formulate and substantiate a clinical diagnosis;
• to prepare a plan of paraclinic patient examination;
• to take samples of material (smears from nasopharynx and stomatopharynx) for
immunoenzyme method and other quick analysis methods and serological examination for
revealing of viruses;
• to evaluate results of paraclinic patient examination;
• to organize hospitalization and treatment of a adenoviral and paragrippal infection patient (of
a person suspected to have adenoviral and paragrippal infection);
• to provide emergency aid at croup;
• to plan and organize prophylactic measures against adenoviral and paragrippal infection;
• to plan and organize antiepidemic measures to localize and liquidate a adenoviral and
paragrippal infection source.
4. Advice to students.
Adenovirus infections most commonly cause illness of the respiratory system;
however, depending on the infecting serotype, they may also cause various other illnesses, such
as gastroenteritis, conjunctivitis, cystitis, and rash illness. Symptoms of respiratory illness
caused by adenovirus infection range from the common cold syndrome to pneumonia, croup,
and bronchitis. Patients with compromised immune systems are especially susceptible to severe
complications of adenovirus infection. Acute respiratory disease (ARD), first recognized
among military recruits during World War II, can be caused by adenovirus infections during
conditions of crowding and stress.
Etiology. Adenoviruses are medium-sized (90-100 nm), nonenveloped icosohedral
viruses containing double-stranded DNA. There are 49 immunologically distinct types (6
subgenera: A through F) that can cause human infections. Adenoviruses are unusually stable to
chemical or physical agents and adverse pH conditions, allowing for prolonged survival outside
of the body.
Recently, several adenoviruses, especially adenovirus 36 (AD-36), have been shown to
cause obesity in animals, and are associated with human obesity Adenoviruses are spread like
the common cold.
Epidemiologic features: Although epidemiologic characteristics of the adenoviruses
vary by type, all are transmitted by direct contact, fecal-oral transmission, and occasionally
waterborne transmission. Some types are capable of establishing persistent asymptomatic
infections in tonsils, adenoids, and intestines of infected hosts, and shedding can occur for
months or years. Some adenoviruses (e.g., serotypes 1, 2, 5, and 6) have been shown to be
endemic in parts of the world where they have been studied, and infection is usually acquired
during childhood. Other types cause sporadic infection and occasional outbreaks; for example,
epidemic keratoconjunctivitis is associated with adenovirus serotypes 8, 19, and 37. Epidemics
of febrile disease with conjunctivitis are associated with waterborne transmission of some
adenovirus types, often centering around inadequately chlorinated swimming pools and small
lakes. ARD is most often associated with adenovirus types 4 and 7 in the United States. Enteric
adenoviruses 40 and 41 cause gastroenteritis, usually in children. For some adenovirus
serotypes, the clinical spectrum of disease associated with infection varies depending on the
site of infection; for example, infection with adenovirus 7 acquired by inhalation is associated
with severe lower respiratory tract disease, whereas oral transmission of the virus typically
causes no or mild disease. Outbreaks of adenovirus-associated respiratory disease have been
more common in the late winter, spring, and early summer; however, adenovirus infections can
occur throughout the year.
The viruses can be spread from person to person via coughing or sneezing. People may
also become infected by touching something with adenovirus on it and then touching their
mouth, nose, or eyes. For example, adenoviruses can be transferred to a doorknob when an
infected person sneezes into his/her hands and then touches the doorknob before washing.
Germs can also be spread if an infected person sneezes or coughs onto tabletops or other items
that might be touched by other people. To prevent the spread of disease, it is important to
practice good health habits.
The viruses are a common cause of infection in humans, but they rarely cause serious or
fatal illness. Adenoviruses cause a wide range of illnesses and symptoms, including colds,
pharyngitis (sore throat), bronchitis, pneumonia, diarrhea, conjunctivitis (eye infection), fever,
cystitis (bladder inflammation or infection), rash illness, neurologic disease.
Since Ad14 infections are not common and most Ad14 infections are not serious, the
emergence of Ad14 should not be a concern to the general population. During the winter, many
other common viral and bacterial infections, including influenza, can present with very similar
symptoms.
Clinical features: Adenoviruses most commonly cause respiratory illness; however,
depending on the infecting serotype, they may also cause various other illnesses, such as
gastroenteritis, conjunctivitis, cystitis, and rash illness. Symptoms of respiratory illness caused
by adenovirus infection range from the common cold syndrome to pneumonia, croup, and
bronchitis. Patients with compromised immune systems are especially susceptible to severe
complications of adenovirus infection. Acute respiratory disease (ARD), first recognized
among military recruits during World War II, can be caused by adenovirus infections during
conditions of crowding and stress.
Diagnosis: Antigen detection, polymerase chain reaction assay, virus isolation, and
serology can be used to identify adenovirus infections. Adenovirus typing is usually
accomplished by hemagglutination-inhibition and/or neutralization with type-specific antisera.
Since adenovirus can be excreted for prolonged periods, the presence of virus does not
necessarily mean it is associated with disease.
Treatment: Most infections are mild and require no therapy or only symptomatic
treatment. Because there is no virus-specific therapy, serious adenovirus illness can be
managed only by treating symptoms and complications of the infection.
Prevention: Vaccines were developed for adenovirus serotypes 4 and 7, but were
available only for preventing ARD among military recruits. Strict attention to good infectioncontrol practices is effective for stopping nosocomial outbreaks of adenovirus-associated
disease, such as epidemic keratoconjunctivitis. Maintaining adequate levels of chlorination is
necessary for preventing swimming pool-associated outbreaks of adenovirus conjunctivitis.
Safe and effective vaccines were developed for adenovirus serotypes 4 and 7, but were
available only for preventing ARD among military recruits, and production stopped in 1996.
Strict attention to good infection-control practices is effective for stopping nosocomial
outbreaks of adenovirus-associated disease, such as epidemic keratoconjunctivitis. Maintaining
adequate levels of chlorination is necessary for preventing swimming pool-associated
outbreaks of adenovirus conjunctivitis.
Human Parainfluenza Viruses
One in a group of four RNA viruses that rank second only to respiratory syncytial virus
(RSV) as a common cause of lower respiratory tract disease in young children. Like RSV,
human parainfluenza viruses (HPIVs) can cause repeated infections throughout life. These
infections are usually manifested by an upper respiratory tract illness (such as a cold or sore
throat). HPIVs can also cause serious lower respiratory tract disease with repeat infection
(including pneumonia, bronchitis, and bronchiolitis), especially among the elderly, and among
patients with compromised immune systems.
There are four serotypes types of HPIV (1 through 4). Each of the four HPIVs has
different clinical and epidemiologic features. The most distinctive clinical feature of HPIV-1
and HPIV-2 is croup (laryngotracheobronchitis); HPIV-1 is the leading cause of croup in
children, whereas HPIV-2 is less frequently detected. Both HPIV-1 and HPIV-2 can cause
other upper and lower respiratory tract illnesses. HPIV-3 is more often associated with
bronchiolitis and pneumonia. HPIV-4 is infrequently detected, possibly because it is less likely
to cause severe disease.
The HPIVs are negative-sense, single-stranded RNA viruses that possess fusion and
hemagglutinin-neuraminidase glycoprotein "spikes" on their surface. The virion varies in size
(average diameter between 150 and 300 nm) and shape, is unstable in the environment
(surviving a few hours on environmental surfaces), and is readily inactivated with soap and
water. Hence, the value of handwashing in combating spread of HPIVs. Clinical features:
Human parainfluenza viruses (HPIVs) are second to respiratory syncytial virus (RSV) as a
common cause of lower respiratory tract disease in young children. Similar to RSV, HPIVs can
cause repeated infections throughout life, usually manifested by an upper respiratory tract
illness (e.g., a cold and/or sore throat). HPIVs can also cause serious lower respiratory tract
disease with repeat infection (e.g., pneumonia, bronchitis, and bronchiolitis), especially among
the elderly, and among patients with compromised immune systems. Each of the four HPIVs
has different clinical and epidemiologic features. The most distinctive clinical feature of HPIV1 and HPIV-2 is croup (i.e., laryngotracheobronchitis); HPIV-1 is the leading cause of croup in
children, whereas HPIV-2 is less frequently detected. Both HPIV-1 and -2 can cause other
upper and lower respiratory tract illnesses. HPIV-3 is more often associated with bronchiolitis
and pneumonia. HPIV-4 is infrequently detected, possibly because it is less likely to cause
severe disease. The incubation period for HPIVs is generally from 1 to 7 days.
The viruses: HPIVs are negative-sense, single-stranded RNA viruses that possess fusion
and hemagglutinin-neuraminidase glycoprotein "spikes" on their surface. There are four
serotypes types of HPIV (1 through 4) and two subtypes (4a and 4b). The virion varies in size
(average diameter between 150 and 300 nm) and shape, is unstable in the environment
(surviving a few hours on environmental surfaces), and is readily inactivated with soap and
water.
Epidemiologic features: HPIVs are spread from respiratory secretions through close
contact with infected persons or contact with contaminated surfaces or objects. Infection can
occur when infectious material contacts mucous membranes of the eyes, mouth, or nose, and
possibly through the inhalation of droplets generated by a sneeze or cough. HPIVs can remain
infectious in aerosols for over an hour. HPIVs are ubiquitous and infect most people during
childhood. The highest rates of serious HPIV illnesses occur among young children. Serologic
surveys have shown that 90% to 100% of children aged 5 years and older have antibodies to
HPIV- 3, and about 75% have antibodies to HPIV-1 and -2. The different HPIV serotypes
differ in their clinical features and seasonality. HPIV-1 causes biennial outbreaks of croup in
the fall (presently in the United States during odd numbered years). HPIV-2 causes annual or
biennial fall outbreaks. HPIV-3 peak activity occurs during the spring and early summer
months each year, but the virus can be isolated throughout the year. The incubation period for
HPIVs is generally from 1 to 7 days. HPIVs are spread from respiratory secretions through
close contact with infected persons or contact with contaminated surfaces or objects. Infection
can occur when infectious material contacts mucous membranes of the eyes, mouth, or nose,
and possibly through the inhalation of droplets generated by a sneeze or cough. HPIVs can
remain infectious in aerosols for over an hour.
HPIVs are ubiquitous and infect most people during childhood. The highest rates of
serious HPIV illnesses occur among young children. Serologic surveys have shown that 90% to
100% of children aged 5 years and older have antibodies to HPIV-3, and about 75% have
antibodies to HPIV-1 and HPIV-2. The different HPIV serotypes differ in their clinical features
and seasonality. HPIV-1 causes biennial outbreaks of croup in the fall (presently in the United
States during odd numbered years). HPIV-2 causes annual or biennial fall outbreaks. HPIV-3
peak activity occurs during the spring and early summer months each year, but the virus can be
isolated throughout the year.
No vaccine is currently available to protect against infection caused by any of the
HPIVs; however, researchers are developing vaccines against HPIV-1 and HPIV-3 infections.
Passively acquired maternal antibodies may play a role in protection from HPIV types 1 and 2
in the first few months of life, highlighting the importance of breast-feeding.
Strict attention to infection-control practices should decrease or prevent spread of
infection. Frequent handwashing and not sharing items such as cups, glasses, and utensils with
an infected person should decrease the spread of virus to others. Excluding children with colds
or other respiratory illnesses (without fever) who are well enough to attend child care or school
settings will probably not decrease the spread of HPIVs, because the viruses are often spread in
the early stages of illness. In a hospital setting, spread of HPIVs can and should be prevented
by strict attention to contact precautions, such as handwashing and wearing of protective gowns
and gloves.
Diagnosis: Infection with HPIVs can be confirmed in two ways: 1) by isolation and
identification of the virus in cell culture or by direct detection of the virus in respiratory
secretions (usually, collected within one week of onset of symptoms) using
immunofluorescence, enzyme immunoassay, or polymerase chin reaction assay, and 2) by
demonstration of a significant rise in specific IgG antibodies between appropriately collected
paired serum specimens or specific IgM antibodies in a single serum specimen.
Prevention: No vaccine is currently available to protect against infection caused by any of
the HPIVs; however, researchers are developing vaccines against HPIV-1 and -3 infections.
Passively acquired maternal antibodies may play a role in protection from HPIV types 1 and 2
in the first few months of life, highlighting the importance of breast-feeding. Strict attention to
infection-control practices should decrease or prevent spread of infection. Frequent
handwashing and not sharing items such as cups, glasses, and utensils with an infected person
should decrease the spread of virus to others. Excluding children with colds or other respiratory
illnesses (without fever) who are well enough to attend child care or school settings will
probably not decrease the spread of HPIVs, because the viruses are often spread in the early
stages of illness. In a hospital setting, spread of HPIVs can and should be prevented by strict
attention to contact precautions, such as handwashing and wearing of protective gowns and
gloves.
Croup is a common respiratory problem characterized by a harsh, barking cough.
Croup most often affects young children. It causes inflammation, swelling, and narrowing
in the voice box (larynx), windpipe (trachea), and breathing (bronchial) tubes that lead to
the lungs.
Croup symptoms often develop a few days after the start of what appears to be an upper
respiratory infection (URI), such as a cold. Most cases are caused by human parainfluenza
viruses types I and II. However, other viruses, such as influenza viruses types A and B,
respiratory syncytial virus (RSV), and measles, can also cause croup. As children grow older
and structures in the throat and breathing tubes mature, they are less susceptible to croup.
Symptoms of croup are caused by a narrowed airway and include a barking cough; a raspy,
hoarse voice; and a harsh crowing noise when breathing in. Croup usually develops after a day
or two of coldlike symptoms, such as a runny nose and congestion. Symptoms of croup often
improve during the day and become worse at night; sometimes children have episodes, or
attacks, of intense symptoms that wake them up in the middle of the night. Usually symptoms
gradually improve within 2 to 5 days.
Even though croup is usually a minor illness, your child's coughing and troubled breathing
can seem severe and frightening, especially during an episode or attack of intense symptoms.
However, even intense symptoms usually improve with home treatment, such as staying calm,
soothing your child, and humidifying the air.
If intense symptoms of croup do not improve after 30 minutes of home treatment, take your
child to an immediate care facility or hospital emergency room. A health professional may give
your child extra oxygen or medication to help open the airway. Most often, your child can then
go home after treatment and observation.
Symptoms
Unless the illness is severe, a child with croup is usually alert and active and doesn't appear
very sick. Symptoms include: Normal temperature or a slight fever. A loud, barking cough. A
raspy, hoarse voice. Varying degrees of high-pitched crowing sounds when breathing in. Some
trouble breathing as a result of swelling in the windpipe.
Exams and Tests
A health professional usually diagnoses croup from a physical examination and a medical
history. During the physical examination, the health professional listens to your child's chest
and back and looks for signs of inflammation or infection in the nose, ears, mouth, and throat.
You will also be asked when your child's symptoms began, whether they have changed, and
whether you have noticed any fever.
Special exams or tests usually are not needed to diagnose croup. However, because the
condition may cause difficulty breathing, a pulse oximeter may be placed on your child's
finger, toe, or earlobe to check the amount of oxygen in the blood. Rarely, an X-ray may be
needed to look at the throat.
Treatment Overview
Home treatment, such as using a cool air humidifier, is normally all that is needed to treat
mild to moderate croup. Usually symptoms gradually improve within 2 to 5 days.
Glucocorticoids, such as dexamethasone (for example, Decadron or Hexadrol) or
budesonide (for example, Pulmicort).
Epinephrine, such as Adrenalin Chloride.
If patient needs extra oxygen, it is given through a nasal cannula or delivered through an
oxygen mask placed over the nose and mouth.
If breathing improves after one or more of these measures, patient will be observed for a
short time and sent home. If symptoms do not improve, patient may need hospitalization and
further testing.
Antibiotics, such as amoxicillin (Amoxil, Trimox, Wymox) or cefpodoxime proxetil
(Vantin), are not effective treatments for croup. These are only used if a secondary bacterial
infection, such as a middle ear infection, develops.
Home treatment usually is all that is needed to treat croup. You can help prevent major
episodes, or attacks, as well as use techniques to manage attacks if they occur.
Preventing croup attacks
You may be able to prevent croup episodes, or attacks, of intense troubled breathing and
coughing. If patient has croup:
Use a cool air humidifier in your child's room. Do not use a hot vaporizer, and make sure to
put only plain water in the humidifier. Although research has not consistently shown that croup
symptoms improve with humidifier use, using one poses very little risk and may benefit your
child. 1 Be sure to empty, clean, and completely dry out the humidifier between each use to
prevent mold growth.
Offer plenty of fluids to drink. Always have water available and try offering other
beverages, frozen ice treats (such as Popsicles), or crushed ice drinks several times each hour.
Do not smoke, especially in the house.
Do not use medications designed for the common cold, which may include antihistamines
(such as chlorpheniramine [for example, Chlor-Trimeton] or diphenhydramine [for example,
Benadryl]) and decongestants (such as pseudoephedrine [for example, Sudafed or Triaminic] or
oxymetazoline [for example, Afrin or Neo-Synephrine]).
Taking measures to manage an episode of croup, such as adding moisture to the air and
keeping your child calm and comfortable, can help keep symptoms under control. If coughing
and difficulty breathing do not improve within about 30 minutes despite your efforts, seek
medical attention from a health professional. Because attacks often occur in the middle of the
night, you may need to visit a hospital emergency room.
5. Test questions.
1. What is adenovirus infection?
2. What causes it?
3. Who gets adenovirus infection?
4. How is adenoviral and paragrippal infection spread?
5. What are the symptoms of adenoviral and paragrippal infection?
6. How soon do symptoms appear?
7. When and for how long is a person able to spread these diseases?
8. How they are diagnosed?
9. What is the treatment for adenoviral and paragrippal infection?
10. What can a person do to minimize the spread of adenoviral and paragrippal infection?
11. Does patient need an antibiotic?
12. Definition of croup.
13. What causes croup?
14. What are the symptoms?
15. How is croup diagnosed?
16. How is it treated?
6. Literature:
A. Basic:
Nikitin E., Andreychyn M., Servetskyy K., Kachor V., Holovchenko A., Usychenko E.
Infectious Diseases. – Ternopil: Ukrmedknyga, 2004. – P. 179-198.
B. Adding:
1. American Academy of Pediatrics. Adenovirus Infections. In: Peter G, ed. 1997 Red
Book: Report of the Committee on Infectious Diseases. 24th ed. Elk Grove Village,
IL: American Academy of Pediatrics; 1997: 131.
2. Horwitz MS. Adenoviruses. In: Fields BN, Knipe DM, Howley PM, eds. Fields
Virology. 3rd ed. Philadelphia: Lippincott-Raven; 1995: 2149-71.
3. Collins PL, Chanock RM, McIntosh K. Parainfluenza viruses. In: Fields BN, Knipe
DM, Howley PM, eds. Fields Virology. 3rd ed. Philadelphia: Lippincott-Raven;
1995: 1205-41.