Review of ESVV congress with focus on viral emerging diseases MASCARON Dépêche Vet oct 2015
Viral emerging and re emerging diseases
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Transcript of Viral emerging and re emerging diseases
VIRUSES
1]Infecting CNS-Japanese encephalitis
2]Infecting RESPIRATORY SYSTEM
-SARS
-Pandemic influenza
History
Geographical distribution
Transmission
Clinical features
Diagnosis and Treatment
Prevention and Control
Genus Flavivirus
Name derived from
the Latin flavus meaning “yellow”
Single stranded, enveloped RNA virus
Morphology not well defined
Different genotypes with single serotype
Replication-Regional lymphnodes
Invasion of CNS-via-Blood
I.P-5 to 15 days
1940 to 1978
› Disease spread with epidemics in China,
Korea, and India [Tamilnadu-1955]
Endemic in
temperate and
tropical regions of
Asia
Disease control by
vaccination
Japan
China
Korea
Indonesia
India Philippines
The three southern states of Tamil Nadu (TN), Andra Pradesh, Karnataka were reporting higher incidence.
JE is emerging as a public health problem in Kerala
In a few villages of Cuddalore district of Tamil Nadu, a known JE-endemic area (Chidambaram, Virudhachalam, Thittakudi)
Vector-borne
Enzootic cycle
› Mosquitoes: Culex species
Culex tritaeniorhynchus
› Reservoir/amplifying hosts
Pigs, bats, Ardeid (wading) birds
Possibly reptiles and amphibians
› Incidental hosts
Horses, humans, others
Center for Food Security and Public Health, Iowa State University, 2011
35,000-50,000 cases annually
Most asymptomatic or mild signs
Children and elderly
› Highest risk for severe disease
Center for Food Security and Public Health, Iowa State University, 2011
Prodromal stage: 1-6 days
Acute encephalitis
› Headache, high fever, stiff neck, stupor
› May progress to paralysis, seizures,
convulsions, coma, and death
Neuropsychiatric sequelae
› 45 to 70% of survivors
In utero infection possible
› Abortion of fetus
Laboratory diagnosis required
Tentative diagnosis
› Antibody titer: HI, IFA, CF, ELISA
› JE-specific IgM in serum or CSF
Definitive diagnosis
› Virus isolation: CSF, brain
No specific treatment
› Supportive care
Vector control
› Eliminate mosquito breeding areas
› Adult and larvae control
Vaccination
› Equine, swine, humans
Personal protective measures
› Avoid prime mosquito hours
› Use of repellants containing DEET
Center for Food Security and Public Health, Iowa State University, 2011
o Caused By- Varient of corona virus
o Emerging disease-2002-03
o Rapid spread in asian countries
o WHO-8422 cases
-916 deaths from 30 countries
o MOT-Respiratory dropletso -Direct contact
-Possible fecal tranmission
o I.P-2 to 7 days
High fever
Virus isolation: inoculate suitable cell culture with patient specimens
When infected by SARS-CoV antibodies
(e.g. IgM and IgG) are produced /
change in level
Enzyme-linked immunosorbent assay
(ELISA)
Immunofluorescence assay (IFA):
Clinical history & observation
Chest radiography: important role
› 70-80% patients have abnormal chest
radiographs
o Immunomodulatory therapy
-Corticosteroido Antiviral Agents
-Ribavirin
oProtease inhibitor -Lopinavir-ritonavir co-formulation
Principle: to break the chain of transmission from infected to healthy person
3-step protocol of disease confinement› Case detection
› Prompt isolation
› Contract tracing Daily health check
Voluntary home isolation
Creation of emergency operating center
Institutional support
› Efficient quarantine measures
› Legislation
International collaboration—WHO
› Travel alerts and restrictions
› Coordination for research
› Agreement of countries on containment
protocol
Seasonal Influenza
› A public health problem each year
› Usually some immunity built up from previous exposures to the same subtype
› Infants and elderly most at risk
Influenza Pandemics
› Appear in the human population rarely and unpredictably
› Human population lacks any immunity
› All age groups, including healthy young adults
Seasonal Epidemics vs. Pandemics
1920 1940 1960 1980 2000
H1N1
H2N2
H3N2
1918: “Spanish Flu” 1957: “Asian Flu” 1968: “Hong Kong Flu”
20-40 million deaths 1-4 million deaths 1-4 million deaths
The new virus must be efficiently transmitted from one human to another
A new influenza virus emerges to
which the general population has
little/no immunity
The new virus must be able to replicate
in humans and cause disease
Viral Re-assortment
Reassortment in pigs
Reassortment in
humans
Pandemic Influenza
Virus
Human Influenza
Type of infection Upper and lower respiratory
Fever Yes
Headache Yes
Cough Yes
Respiratory symptoms Varies; sore throat to difficulty
breathing
Gastrointestinal
symptoms
Uncommon, except children,
elderly
Recovery 2-7 days
Isolation Precautions
Source: Rosie Sokas, MD MOH UIL at
Chicago
Droplet precautions:
Surgical Masks
Personal Protective Equipment
(PPE)
Thank you