Dra de Castro Microbiology – Hepatitis A-E Viruses: An Overview by Overview by Dra
A. Clin Clinic ical al Featu eature res s o Incubation period: days
Average 60-90
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D. Global Global Patter Patterns ns of Chronic Chronic HBV HBV Infection Infection o High (>8%): (>8%): 45% of global population population lifetime risk of infection >60% early childhood infections common o Intermediate Intermediate (2%-7%): 43% of global population lifetime risk of infection 20%-60% infections occur in all age groups o Low (<2%): 12% of global population lifetime risk of infection <20% most infections occur in adult risk groups E. Geog Geogra raph phic ic Distr Distrib ibut utio ion n F. Concentr Concentration ation of HBV HBV in Various Various Body Fluids Fluids High Moderate Low/Not Detectable blood semen urine serum vaginal fluid feces wound exudates saliva sweat tears breast milk G. Mode of Transmission o Sexual Sex workers and homosexuals are particular at risk o Parenteral IVDA, health workers are at increased risk o Perinatal Mothers who are HBeAg positive are much more likely to transmit to their offspring than those who are not Perinatal Perinatal transmission is the main means of transmission in high prevalence prevalence population H. Labo Labora rato tory ry Diag Diagno nosi sis s o A batter battery y of sero serolog logica icall tests tests are used used for the diag diagno nosi sis s of acut acute e and and chr chronic onic hepa hepati titi tis s B infection o HBsAg Used as a general marker of infection o HBsAb Used to document recovery and/or immunity toHBV infection o Anti-HBc IgM Marker of acute infection o Anti-HBc IgG Past or chronic infection o HBeAg Indi Indica cate tes s acti active ve repl replic icat atio ion n of viru virus s and and therefore infectiveness o Anti-HBe Virus no longer replicating However, the patient can still be positive for HBsAg which is made by integrated HBV o HBV-DNA Indicates active replication of virus More accurate than HBeAg especially in cases of escape mutants Used Used main mainly ly for for moni monito tori ring ng resp respon onse se to therapy I. Treatment o Interferon For HBeA HBeAg g posi positi tive ve carr carrie iers rs with with chro chroni nic c active hepatitis Response rate is 30 to 40% o Lamivudine A nucleoside analogue reverse transcriptase inhibitor Well, Well, tolerate tolerated, d, most patients patients will respond respond favorably
Range 45-180 days o Clinical ilillness (j (jaundice): <5 yrs, <10% >5 yrs, 30%-50% o Acute case-fatality rate: 0.5%-1% o Chronic infection: <5 yrs, 30%-90% >5 yrs, 2%-10% o Premature mortality from chro chroni nic c live liverr dis disea ease se:: 15%15%-25 25% % B. Spectrum Spectrum of Chro Chronic nic Hepatitis Hepatitis B Disea Diseases ses o Chronic Persistent Hepatitis Asymptomatic o Chronic Active Hepatitis Symptomatic exacerbations exacerbations of hepatitis o Cirrhosis of liver o Hepatocellular carcinoma C. Sero Serolo logi gica call cour course se Acute Hepatitis B Virus Infection with Recovery Typical Serologic Course
Symptoms
HBeAg
anti-HBe
Total anti-HBc
r e t i T
IgM anti-HBc anti-HBs
HBsAg
0
4
8
12
16 16
20
24
28
32
52
36
100
Weeks after Exposure
Progression to Chronic Hepatitis B Virus Infection Typical Serologic Course Acute
Chronic
(6 months)
(Years)
HBeAg
anti-HBe
HBsAg
Total anti-HBc r e t i T
IgM anti-HBc
0
4
8
12 16 20 2 4 28 32 36
52
Weeks after Exposure
Outcome of Hepatitis B Virus Infection by Age at Infection
100
) % ( n o i t c e f n I c i n o r h C
100
80
80
60
60
Chronic Infection
40
40
20
20
Symptomatic Infection 0 th r i B
s o m - 6 1
s o m 2 - 1 7
sr y - 4 1
n er dl i h C r e n dl a O
0
S y m p to m a t ci In f e c ti o n % ( )
Dra de Castro Microbiology – Hepatitis A-E Viruses: An Overview by Overview by Dra
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However, tendency tendency to relapse on cessation of treatment Anti-HCV Another problem is the rapid emergence of Symptoms +/drug resistance o Successful response to treatment will result in the HCV RNA dis disappe appear aran ance ce of HBsAg, Ag, HBV-DNA -DNA,, and and r e t i seroconversion to HBeAg T J. Prevention ALT o Vaccination Highly Highly effective effective recombi recombinant nant vaccines vaccines are Normal now available 6 1 2 3 4 0 1 2 3 4 5 Vaccine accine can be given given to those those who who are are at Years Months increased risk of HBV infection such as health Time after Exposure care workers It is also also give given n rout routin inel ely y to neon neonat ates es as D. Mode Mode of Transmi ransmissi ssion on universal vaccination in many countries o Risk Factors Associated with Transmission o Hepatitis B Immunoglobulin Immunoglobulin Transfusion or transplant from infected donor HBIG may be used to protect persons who are Injecting drug use exposed to hepatitis B Hemodialysis (yrs on treatment) It is particular efficacious within 48 hours of Accidental injuries with needles/sharps the incident Sexua Sexual/h l/hou ouseh sehold old expos exposur ure e to anti-H anti-HCV CV-It may also be given to neonates who are at positive contact increased risk of contracting hepatitis B i.e. Multiple sex partners whos whose e moth mothe ers are are HBsA HBsAg g and and HBeA HBeAg g Birth to HCV-infected mother positive E. Geog Geogra raph phic ic Distr Distrib ibut utio ion n o Other measures F. Labo Labora rato tory ry Diag Diagno nosi sis s Screenin Screening g of blood donors, donors, blood blood and body o HCV antibody fluid precautions Gene Genera rall lly y used used to diag diagno nose se hepa hepati titi tis s C infection Hepatitis C Virus Not useful in acute phase as it takes at least 4 week weeks s afte afterr infe infect ctio ion n befo before re anti antibo body dy HCV genome appears o HCV-RNA Various Various techniques are available e.g. PCR and branched DNA May be diagnose HCV infection in the acute phase A. Clin Clinic ical al Featu eature res s However, However, its main use is in monitoring monitoring the Incubation period: Average 6 -7 o response to antiviral therapy weeks o HCV-antigen Range 2-26 weeks An EIA for HCV antigen is available o Clinical illness (jaundice): 30 – 40% (20 – It is used in the same capacity as HCV-RNA 30%) tests but is much easier to carry out o Chronic Hepatitis: 70% G. Treatm eatmen entt o Persi rsiste stent In Infect fectiion: on: 85 – 100 100% o Interferon o Immunity: No protective antibody May be considered for patients with chronic response identified active hepatitis B. Chron Chronic ic Hepa Hepatit titis is C Infec Infectio tion n The response rate is around 50% but 50% of o The spectrum of chronic hepatitis C infection is respond responders ers will relapse relapse upon withdrawal withdrawal of esse essent ntia iall lly y the the same same as chro chroni nic c hepa hepati titi tis s B treatment infection o Ribavirin o All All the the mani manife fest stat atio ions ns of chro chroni nic c hepa hepati titi tis s B There There is less experienc experience e with ribavirin ribavirin than infe infect ctio ion n may may be seen seen,, albe albeit it with with a lowe lowerr interferon frequency frequency i.e. chronic persistent hepatitis, chronic active active hepat hepatiti itis, s, cirrh cirrhosi osis, s, and hepat hepatoce ocellu llular lar Howe Howeve ver, r, rece recent nt stud studie ies s sugg sugges estt that that a carcinoma combin combinati ation on of interf interfer eron on and ribavi ribavirin rin is C. Sero Serolo logi gica call cour course se more effective than interferone alone Typical Serologic Course of HCV Infection H. Preven ventio tion o Screening of blood, organ, tissue donors o High-risk behavior modification o Blood and body fluid precautions
Hepatitis D Virus
Dra de Castro Microbiology – Hepatitis A-E Viruses: An Overview by Overview by Dra
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A. Clin Clinic ical al Featu eature res s o Incubation period:
HDV is a defective single-stranded single-stranded RNA virus that requires the helper function of HBV to replicate. HDV requires HBV for synthesis of envelope protein composed of HBsAg, which is used to encapsulate the HDV genome. A. Clin Clinic ical al Featu eature res s o Coinfection severe acute disease
Average 40 days Range 15-60 days o Case-fatality rate: Overall, 1%-3% Pregnant women, 15%25% Illness se severity: Increased with age o Chronic sequelae: None identified o B. Sero Serolo logi gica call cour course se
low risk of chronic infection Superinfection
o
usually develop chronic HDV infection high risk of severe chronic liver disease may present as an acute hepatitis
B. Mode of Transmission Percutaneous exposures Injecting drug use o Permucosal exposures Sex contact C. Sero Serolog logic ical al cour course se o
C. Epide Epidemio miolog logic ic Featur eatures es o Most outbr utbre eaks aks asso associ cia ated ted with faec aecally ally contaminated drinking water o Seve Several ral other other large large epide epidemic mics s have have occur occurre red d since in the Indian subcontinent and the USSR, China, Africa and Mexico o In the U.S. and other nonendemic areas, where outbreaks of hepatitis E have not been documented to occur, a low prevalence of antiHEV (<2%) has been found in healthy popula populatio tions. ns. The sourc source e of infect infection ion for these these persons is unknown o Minimal person-to-person transmission D. Geogr Geograph aphic ic Distri Distribu butio tion n E. Prevention o Avoid drinking water (and beverages with ice) of unknown purity, uncooked shellfish, and uncooked fruit/vegetables not peeled or prepared by traveler o IG prepared from donors in Western countries does not prevent infection o Unknown efficacy of IG prepared from donors in endemic areas o Vaccine? ♥
D. Geogr Geograph aphic ic Distri Distribut bution ion E. Prevention o HBV-HDV Coinfection Pre or postexposure prophylaxis to prevent o HBV-HDV Superinfection Education to reduce risk behaviors among persons with chronic HBV infection
Hepatitis E Virus
end♥
Thoughts brought about by watching Just Like Heaven and Prozac Nation successively. successively. :) I have no need of food. I have no need of sleep. I have no needs other than occasionally chewing a breath mint. YOU ARE THE BEST THING THAT’S EVER HAPPENED TO ME.. probably because it haven’t happened to me yet. Now, I can pass into the next act, so poetically called: euphoria.
Dra de Castro Microbiology – Hepatitis A-E Viruses: An Overview by Overview by Dra
I feel so good. I feel so strong. I feel actually attractive and I could learn to live with that feeling. But what if I’m no good at this? I am no good at this. I am a dingy speck on the wall of humanity and look how badly painted the wall is! I am be beco comi ming ng ve very ry,, ve very ry af afra raid id.. Th That at mu must st be because I’m passing into the third act called: fear. Oh no! What if I’m wrong? What if this stinks? What if my heart has blinders on, it had blinders on before.. in fact it had dark, heavy patches taped all over it. How can anyone love me if I don’t love myself? I mean, I love myself; there are just parts between the top of my head and th the e bo bott ttom om of my fe fee et th that at co cou uld use so som me improvement. I’m not demeaning my self.. I can’t believe I ever said I felt this way. I must have been dreaming! Wait! This is no dream.. This is a film or movie, and one of those really dark ones too. I mean.. Is this love? This is what they tell you about when you’re naive. The truth: love is har hard d work work.. And sometimes, sometimes, hard work can really hurt. Love is a game. Love is a game and if you play.. You either win, lose or get ejected before the game is over. There are no ties. Maybe you’ll lose and learn some great meaningful answer from it all (like, if it looks too good to be true, it is). It’s easy to love something when you don’t have to work at it. It’s harder when it asks something of you, you just might be afraid to give.. give it anyway. The heart is the most resilient muscle. It is also the stupidest. So if this love you’ve found is good to you, hold it.. keep it.. shout about it. If it isn’t, then maybe you should just become very good friends. So thi this s is lov love, e, as de deman mandin ding g and nourish nourishing ing and difficult as it can be, and as strong and wise as it makes you become. There is something to be gained from commitment. There There are rew rewards ards for stay staying ing when you would rathe ratherr leave. And there’s something to be said for running up that hill when you would rather slide down it. And so, you let love come perch upon your shoulder.. and you don’t turn it away. *oh no! May space p din.. di ko n xa kaya I fill up.. oh well. ;o) stay in love! Hehe! ;o) *di *di ko sin sinama ama un geogr geograph aphica icall dis distri tribut bution ion n pix kc magiging sobrang minute n un pix. Ky d n ntin makikita un distribution nya. hehe. ;op if ever may gs2 magadik nun geo pix.. txt nyo lng me.. icsend ko s inyo (nandun din un geo pix s patho hepa trans natin). ;o) xoxo
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