Case histroy 1
A child presented to OPD with complaints of
passage of loose stools for the past 2 days. The stools are not fowl smelling, and are watery in consistency with the presence of blood but no mucus
.
What can be the etiology
?
Case history 2
In a military recruits posted in the valley, 5 of the army men developed fever, sore throat, nasal congestion, cough and malaise. Four of these recovered and in 1 of them the illness progressed to pneumonia
.
What can be the etiology
.
Case History 3
chlidren developed fever , conjunctivitis and 3 pharyngitis 3 days after a summer camp
.
What can be the etiology
?
Case history 4
A 10 year old boy was brought to the casuality with the history of passage of blood in urine
.
Etiology again a question
?
ADENOVIRUS
ADENOVIRUS
DNA viruses first isolated from
adenoidal tissue in 1953
ADENOVIRUS
Family
AdenoviridaeGenus
Mastadenovirus AviadenovirusADENOVIRUS - Structure
Non-enveloped DNA virus 70-90 nm in size
Linear ds DNA genome with core proteins
ADENOVIRUS - Ultra structure
Icosahedral capsid with 252 capsomeres (12 pentons at vertices and 240 hexons)
Each penton has a fibers with terminal knob projecting from it
Adenovirus- 3 D structure
ADENOVIRUS - Classification
Subgroups- 6 subgroups (A-F), based on
hemagglutination, DNA fragment analysis, Fibre length and oncogenic potential
Serotypes- 1-47 (human)
Common serotypes:- 1-8, 11, 21, 35, 37, 40
Enteric Adenoviruses belong to subgroup F
TRANSMISSION
Droplets
Fecal-oral route
Direct and through poorly chlorinated water Fomites
Time-course of infection
Incubation period- 2-14 days
Infective period continues for weeks
Intermittent and prolonged rectal shedding
Secondary attack rate within families up to 50%
EPIDEMIOLOGY
Endemic, epidemic and sporadic infections Many infections are sub-clinical
EPIDEMIOLOGY-contd.
’Tip of the iceberg phenomenon’
Classical disease presentation
Mild clinical disease
Asymptomatic infection but +infectivity
EPIDEMIOLOGY- Outbreaks
Military recruits,
swimming pool users, hospitals,
residential institutions, day care settings
CLINICAL SYNDROMES
Respiratory Eye
Genitourinary
Gastrointestinal
Others
Acute Respiratory Disease (LRI)
Fever
Tracheobronchitis Pneumonia
Children and adults
Epidemics in military recruits
Types 4 and 7 most frequently
Pharyngoconjunctival fever
Headache, fever, malaise
Conjunctivitis and Pharyngitis
Cervical adenopathy, rash and diarrhea also Main adenovirus types: 3, 4, 7, 14
Epidemics in summer months
Contaminated water in swimming pools, fomites
Adenoviral Infections of the eye
Epidemic Keratoconjunctivitis (EKC) Acute follicular conjunctivitis
Pharyngoconjunctival fever
Adenoviral conjunctivitis
Early conjunctivitis (top) and Bilateral conjunctivitis (lower)
ADENOVIRAL INFECTIONS- Genitourinary system
Acute hemorrhagic cystitis
• fever, dysuria, hematuria
• Types 11, 7, 4, 21, 1
• More common in boys
Others
• Orchitis, nephritis, cervicitis with ulcerated vesicular lesions, urethritis
• Types 2, 8, 19, 37
Other Infections due to Adenovirus
•Myocarditis
•Pericarditis
•Meningitis
•Rash
•Arthritis
Adenovirus infections in Immunocompromised hosts
Disseminated, severe and often fatal infections
Due to new infection or reactivation of latent virus
Prolonged infections with prolonged viremia and viral shedding
Necrotizing pneumonia, hepatitis, rash, disseminated intravascular coagulation (DIC), CNS involvement
DIAGNOSIS OF ADENOVIRAL INFECTIONS
• Variety of clinical specimens depending on clinical syndrome-NP, conjunctival, stool, urine,
• tissue, etc.
• Transport in viral transport media
• Isolation from pharyngeal site correlates better with current clinical infection
ADENOVIRAL INCLUSION
BODIES
Methods for diagnosis
Culture in HeLa, Hep2 cell lines Shell vial cell culture
DFA ELISA
PCR, nucleic acid probes EM and Immune EM
ADENOVIRUS VACCINE
• Oral live attenuated vaccine
• Strains 4, 7
• Used in military recruits
• Manufacture of vaccine was halted in 1996
• Lapse in immunization was associated with
outbreaks in military recruits
Adenovirus
Used as VECTORS to transfer desired genetic material into cells
Viral genome is relatively easily manipulated in vitro
Efficient expression of inserted DNA in recipient cell
THANKS
Gastrointestinal Infections
Types 40, 41 Age <4 years
• Diarrhea lasts for 10-14 days
• Fever
• Also, intussusception, mesenteric adenitis, appendicitis