HEPATITIS A

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TYPE A HEPATITIS

Type A Hepatitis(infectious hepatitis) is a subacute disease of global distribution effecting mainly children and young adults.

CLINICAL FEATURES : The large majority of infections are asymptomatic. Overt illness is seen in only about 5% . Incubation period is about 2-6 weeks.

clinical disease consists of two stages:

  • prodromal or preicteric
  • icteric
onset may be acute or insidious, with fever,malaise,anorexia,nausea,vomiting,and liver tenderness.Recovery is slow, over a periode of 4-6weeks.

Very rarely a rapidly fatal fulminant hepatitis may occur. Mortality is low 0.1-1% with most of the deaths occurs in adults.

HEPATITIS A VIRUS

Morphology: HAV is a 27-nm,non enveloped RNA virus belongs to picornavirus family. HAV is recognised as the prototype of new genus HEPATOVIRUS.

Resistance: HAV is resistant to inactivation by heat at 60'C for an hour, either and acid at  pH 3,but it is inactivated by boiling for 1 minute,1:4000 formaldehyde at 37'C for 72 hours,and chlorine 1ppm for 30min.

It is not affected by anionic detergents. It can survive at prolonged storage at temp of 4'C.

Diagnosis:

  • Antigen/antibody tests

  • Antibody tests
  • Nucleic acid tests (NATs)

Test for treatment:

  • CD4 T cell count.
  • Viral load (HIV RNA)

  • Drug resistance.
The classes of anti -HIV drugs include:

  • Non-nucleoside reverse transcriptase inhibitors (NNRTIs) 1.Sustiva., 2.Edurant.
  • Nucleoside or nucleotide reverse transcriptase inhibitors (NRTIs) 1.Ziagen,2 viread,3 Emtriva,4 retrovir.
  • Protease inhibitors (PIs) 1.Reyataz, 2.Prezista 3.Kaletra
  • Integrase inhibitors  1.Biktarvy ,2 Isentress, 3.Tivicay
  • Entry or fusion inhibitors Fuzeon

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