Swine Flue & Dengue

7/29/2019 Swine Flue & Dengue

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Prepared by

Mukeshkuma P. Tank


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Swine influenza, also called pig influenza,swine flu, hog flu and pig flu, is an infection

by any one of several types of swine influenzavirusesSIV strains include influenza C and thesubtypes of influenza A known as H1N1,H1N2, H2N1, H3N1, H3N2, and H2N3.


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Most people with dengue recover without anyongoing problems. The mortality is 1 5% withouttreatment,and less than 1% with adequate treatment;

however severe disease carries a mortality of 26%.Dengue is endemic in more than 110 countries.[ Itinfects 50 to 100 million people worldwide a year,leading to half a million hospitalizations, and

approximately 12,500

25,000 deaths.The most common viral disease transmitted byarthropods,dengue has a disease burden estimated tobe 1600 disability-adjusted life years per millionpopulation,


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virus from pigs to humans is not common anddoes not always lead to human flu, often

resulting only in the production of antibodiesin the blood.If transmission does cause human flu, it iscalled zoonotic swine flu. People with regular exposure to pigs are at increased risk of swineflu infection


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three genera of influenza viruses that causehuman flu, two also cause influenza in pigs, withinfluenza

A being common in pigsB has not been reported in pigs.C being rare

influenza A and influenza C, the strains found in pigs and humans are largely distinct, although because of reassortment there have been transfersof genes among strains crossing swine, avian, andhuman species boundaries.


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Influenza viruses infect both humans and pigs, but do not infect birds

Transmission between pigs and humans haveoccurred in the past.Influenza ASwine influenza is known to be caused byinfluenza A subtypes H1N1,H1N2,H2N3,H3N1,and H3N2.


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Although there is no formal nationalsurveillance system in the United States to

determine what viruses are circulating inpigs,an informal surveillance network in theUnited States is part of a world surveillancenetwork


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pandemics can be traced before 1918. Around1918, the ancestral virus, of avian origin,crossed the species boundaries and infectedhumans as human H1N1.The new human H1N1 flu strain of avianorigin kept transmitting among human

populations until around 1957a new strain (H2N2). From this pointonwards, no outbreaks of H1N1 werereported in humans until around 1976.


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1968,avian strain H1N1 infected humans againthis time the virus met the strain H2N2, and thereassortment originated the strain H3N2.

The mid-1970shuman H1N1 strain became a seasonal strain

2009 outbreak was between 1990 and 1993new human H1N1 strain, which caused the 2009

pandemic.On June 11, 2009, the World Health Organizationraised the worldwide pandemic alert level to Phase 6


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The main route of transmission is throughdirect contact between infected and uninfected

animalsIntensive farming by pigs touching noses, or through driedmucus.Airborne transmission through the aerosols

produced by pigs coughing or sneezingthrough wild animals, such as wild boar


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People who work with poultry and swinerisk of infection are veterinarians and meat

processing workers, although the risk of infection for both of these groups is lower thanthat of farm workers.


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Centers for Disease Control and Prevention(CDC), in humans the symptoms of the 2009"swine flu" H1N1 virus are similar to those of influenza and of influenza-like illness ingeneral.

fever, cough, sore throat, body aches, headache,

chills and fatigue.The 2009 H1N1 virus is not zoonotic swine flu,as it is not transmitted from pigs to humans,but from person to person.


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of a respiratory sample (a simple nose and throatswab).-time RT-PCR as the method of choice fordiagnosing H1N1.Death due to:

respiratory failure, pneumonia (leading to sepsis),high

fever (leading to neurological problems), dehydration(from excessive vomiting and diarrhea), electrolyteimbalance and kidney failure. Fatalities are morelikely in young children and the elderly


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Prevention of swine influenza has threecomponents:

prevention in swine,

prevention of transmission to humans, and

prevention of its spread among humans. Avoid touching your eyes, nose or mouthIs most contagious during the first five days of the illness,


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include using standard infection control, whichincludesfrequent washing of hands with soap and wateror with alcohol-based hand sanitizers, especiallyafter being out in public.Chance of transmission is also reduced bydisinfecting household surfaces, which can bedone effectively with a diluted chlorine bleachsolution.staying away from other people


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Vaccination Antiviral i.e. Tamiflu or zanamivir Relenza

SymptomaticHydrate patient.


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known as breakbone fever, is an infectioustropical disease caused by the dengue virus.


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Dengue is transmitted by several species of mosquito within the genus Aedes, principally

A. aegypti.


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. include fever,headache,

muscle and joint pains,characteristic skin rash that is similar tomeaslesdengue hemorrhagic fever dengue shock syndrome, where dangerouslylow blood pressure


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asymptomatic (80%) or only have mildsymptoms such as an uncomplicated fever.

more severe illness (5%), and in a small proportion it is life-threatening.


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ranges from 3 14 days, but most often it is 4 7days.Therefore, travelers returning from endemic areasare unlikely to have dengue if fever or other symptoms start more than 14 days after arrivinghome.Children often experience symptoms similar tothose of the common cold and gastroenteritis(vomiting and diarrhea), but are more susceptibleto the severe complications.


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The characteristic symptoms of dengue aresudden-onset fever, headache (typically located

behind the eyes),muscle and joint pains, and a rash.The alternative name for dengue, "break-bonefever", comes from the associated muscle and joint pains.


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febrile, critical, and recoveryThe febrile phase involves high fever, often over 40 C (104 F), and is associated with generalized

pain and a headache; this usually lasts two toseven days.At this stage, a rash occurs inapproximately 50 80% of those with symptoms.It occurs in the first or second day of symptomsas flushed skin, or later in the course of illness(days 4 7), as a measles-like rash.Some

petechiae, some mild bleeding from the mucousmembranes of the mouth and nose.


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follows the resolution of the high fever and typically lastsone to two days.During this phase there may be significant fluidaccumulation in the chest and abdominal cavity due toincreased capillary permeability and leakage. This leads todepletion of fluid from the circulation and decreased bloodsupply to vital organs.During this phase, organ dysfunctionand severe bleeding, typically from the gastrointestinaltract, may occur.

Shock (dengue shock syndrome) and hemorrhage (denguehemorrhagic fever) occur in less than 5% of all cases of dengue, however those who have previously been infectedwith other serotypes of dengue virus ("secondaryinfection") are at an increased risk.


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occurs next, with resorption of the leakedfluid into the bloodstream. This usually lasts

two to three days.The improvement is often striking, but theremay be severe itching and a slow heart rate.During this stage, a fluid overload state mayoccur; if it affects the brain, it may cause areduced level of consciousness or seizures.


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Dengue can occasionally affect several other bodysystems,[8] either in isolation or along with the classicdengue symptoms.A decreased level of consciousness

occurs in 0.5 6% of severe cases, which is attributableeither to infection of the brain by the virus orindirectly as a result of impairment of vital organs, forexample, the liver.Other neurological disorders have been reported inthe context of dengue, such as transverse myelitis andGuillain-Barr syndrome. Infection of the heart andacute liver failure are among the rarer complications


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Dengue fever virus (DENV) is an RNA virusof the family Flaviviridae;

members of the same genus include yellowfever virus, West Nile virus, St. Louisencephalitis virus, Japanese encephalitis virus,tick-borne encephalitis virus, Kyasanur forestdisease virus, and Omsk hemorrhagic fever virus.


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transmitted by arthropods (mosquitoes or ticks), and are therefore also referred to as

arboviruses (arthropod-borne viruses).the virus particle and seven other types of protein molecules (NS1, NS2a, NS2b, NS3, NS4a, NS4b, NS5) that are only found ininfected host cells and are required for replication of the virus.


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The severe complications on secondaryinfection occurs particularly if someone

previously exposed to serotype DENV-1 thencontracts serotype DENV-2 or serotypeDENV-3, or if someone previously exposed totype DENV-3 then acquires DENV-2.


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The mosquito Aedes aegypti feeding off a human host bite primarily during the dayAn infection can be acquired via a single bite.A female mosquitothat takes a blood meal from a person infected with dengue fever

becomes itself infected with the virus in the cells lining its gut.About 8 10 days later, the virus spreads to other tissues includingthe mosquito's salivary glands and is subsequently released into itssaliva. The virus seems to have no detrimental effect on themosquito, which remains infected for life. Aedes aegypti prefers tolay its eggs in artificial water containers, to live in close proximityto humans, and to feed off people rather than other vertebrates.


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Dengue can also be transmitted via infected blood products and through organ donation. In

countries such as Singapore, where dengue isendemic, the risk is estimated to be between1.6 and 6 per 10,000 transfusions. Verticaltransmission (from mother to child) during

pregnancy or at birth has been reported.Other person-to-person modes of transmission havealso been reported, but are very unusual.


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Severe disease is more common in babies andyoung children, and in contrast to many other

infections it is more common in children thatare relatively well nourished. Women aremore at risk than men. Dengue can be life-

threatening in people with chronic diseasessuch as diabetes and asthma.


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When a mosquito carrying dengue virus bites a person, the virus enters the skin together with themosquito's saliva.

It binds to and enters white blood cells, andreproduces inside the cells while they movethroughout the body.The white blood cells respond by producing anumber of signaling proteins, such as interferon,which are responsible for many of the symptoms,such as the fever, the flu-like symptoms and thesevere pains.


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In severe infection, the virus production inside the body is greatly increased, and many more organs (suchas the liver and the bone marrow) can be affected, and

fluid from the bloodstream leaks through the wall of small blood vessels into body cavities. As a result, less blood circulates in the blood vessels, and the blood pressure becomes so low that it cannot supplysufficient blood to vital organs. Furthermore,dysfunction of the bone marrow leads to reducednumbers of platelets, which are necessary for effective

blood clotting; this increases the risk of bleeding, theother major complication of dengue fever


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Warning signs Abdominal painOngoing vomitingLiver enlargementMucosal bleedingHigh hematocrit with low platelets

Lethargyon the findings of fever plus two of the following:nausea and vomiting, rash, generalized pains, lowwhite blood cell count, positive tourniquet test,


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The World Health Organization's 2009classification divides dengue fever into two

groups:uncomplicated andsevere.


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done by virus isolation in cell cultures,nucleic acid detection by PCR,

viral antigen detection or specific antibodies(serology).Tests for dengue virus-specific antibodies,

types IgG and IgM,


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depends on control of and protection from the bites of the mosquitoIntegrated Vector Control program

Advocacy,social mobilization and legislation to ensure that public health bodies and communities are strengthened,collaboration between the health and other sectors(public and private),A. aegypti is by eliminating its habitatsReducing open collections of water throughenvironmental modificationapplication of insect repellent


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depends on the symptoms,oral rehydration therapyhospital admission with administration of

intravenous fluids and/or blood transfusion"warning signs"hematocrit.urinary output of 0.5 1 mL/kg/hr,Invasive medical procedures such as nasogastricintubation, intramuscular injections and arterial

punctures are avoidedParacetamol (acetaminophen) avoid aspirinbrufen


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Swine Flue & Dengue