Properties of some important viruses for microbiology students, including morphology, infection, incubation time, symptoms, assay, antiviral drug.
| S.N. | Virus | Morphology | Infection | I.P. | Symptoms | Specimen | Assay | Antiviral | Vaccine |
| 1 | Small Pox (Variola Virus) | Size: 400-240-100 Nucleic Acid: DNA Envelope: Present Antigen. LS | No animal reservoir, Virus enters through the respiratory mucosa multiples in draining lymph node | About 12 days | Fever, skin rash in buccal mucosa ten skin, maculopapular rash in face to trunk. Maculopapular>macules>papules>vesicles>pustules | Infected epithelial cells | Microscopic Examination of epithelial cell, Culture in CAM, Kidney cell Culture, detection of viral antigen | Methimazole (Prophylaxis) | Live attenuated from calf lymph |
| 2 | Herpes Simplex | Size: 50-200 nm Nucleic Acid: dsDNA Envelope: Present Antigen: attachment protein (gD, gC, gD), fusion protein (gB), Structural protein (gC, gE, gI) | Secretion and lesion of mucosal and cutaneous surface | 3-6 days | HSV-1; Vesicles formation under the layer of keratinized squamous epithelial cells, encephalitis HSV-2; GTI (Genital Tract Infection), meningitis | Vesicle fluid, Vesicle swab | Microscopic: >1% toluidine blue(aq) or by Giemsa’s stain Culture: CAM (Chorioallantoic Membrane) or Human Embryonic Tissue or Hella Cells. Antigen Detection: PCR test for viral DNA Serology: ELISA, CFT, Neutralization Test | Acyclovir (within 72 hrs); orally or parenterally Tropical Onintment | No |
| 3 | Hepatitis | Size: A/B/C = (27/42/40) nm Nucleic Acid: A/B/C = (+ssRNA/dsDNA/+ssRNA) Envelop: A/B/C =(No/Yes/Yes) Antigen: B/C = (HBsAg, HBcAg, HBeAg/E1, E2, P7, NS) | A= Faeco-oral B/C= Parental sexual | A= 15-50 days B= 45-160 days C=14-180 dayss | HAV; Fever, fatigue, nausea, vomiting, abdominal pain, jaundice, hepatomegaly HBV/HCV; Chronic Hepatitis and Liver Cancer | HAV; faces HBV/HCV; Blood, Body Secretion | Antibody; HAV; Detection of anti-HAV IgM by ELISA or radioimmunoassay, presence of IgG denotes recent or past infection and immunity. Antigen: Detection of HBsAg by ELISA and Rapid test kit, Latex agglutination test, Elevation of glucuronic transferase & bilirubin Detection of anti-HCV IgG by ELISA or IgG, IgM, Rapid Test Kit | ||
| 4 | Mumps | Size: 100-300 nm Nucleic Acid: -ssRNA Envelope: Present Antigen: NH, N | Inhalation | 16-18 days | Malaise, anorexia, fever, enlargement, of parotid and salivary glands with pain | Secretion of throat / Urine /CSF | Microscopy: Immunofluorescence Culture: Primary Monkey Kidney or Hep-2 cell culture Serology: ELISA, HI, IgG or IgM | No | Live attenuated Vaccine |
| 5 | Measles Rubella) | Size: 100-250 nm Nucleic Acid: -ssRNA Envelope: Present Antigen: H, F, CD46, CD150 | Respiratory droplets | 8-12 days | High fever Coryza(runny nose), Conjunctivitis, Cough, Koplik’s spot (small red spots with a bluish white center on the buccal mucosa) | Nasopharyngeal and conjunctivital swab, blood, respiratory secretion, urine | Antigen Detection: Immunofluorescence, Giemsa’s stain, PCR Culture: Human fibroblasts, monkey kidney cell or Human Cell Line Serology: ELISA, HI, CF, Nt test > IgM | No | Live attenuated Vaccine |
| 6 | Influenza | Size: 80-120 nm Nucleic Acid: -ssRNA Envelope: Present Antigen: M1, M2, HA, NA | Aerosol generated by Cough and sneezes | 1-4 days | Fever, chills, headache, dry, Cough, generalized myalgia | Nasal washing, gargles, throat swab | Antigen detection: In exfoliated cell by ELISA, PCR, RIA Culture: egg inoculation (11-13 days old), tissue culture, Monkey kidney cell, human embryo kidney cell) Serology: Hemagglutination inhibition or complement fusion or ELISA | Amantadine(rimantadine) Zanamivir, Oseltamivir | 70% effective Inactivated Vaccine, Live virus vaccine |
| 7 | HIV | Size: 90-120 nm Nucleic Acid: +ssRNA Envelope: Present Antigen: gp41, gp120, p9, p17, p7, p24, p15, p55, p18, p31, p55, p66 | STD, Semen and vaginal discharge, breast feeding, blood | 1-10 years | Pneumonia, Kaposi’s sarcoma 10% wight loss, diahorrea | Blood | Specific test= Serology test: ELISA(Antibody), Western Blot (Antigen), Rapid tests (Antigen, Antibody) Test for Virus Components: assay of p24 antigenemia, detection of virus nucleic acid, Virus isolation. Non-Specific test: Blood cell count, Hyper gammaglobulinemia, opportunistic infection | Zidovudine, Didanosine, Zalcitabine, Lamivudine | No |
| 8 | Rota | Size: 65-70 nm Nucleic Acid: +dsDNA Envelope: Antigen: VP4, VP7 | Faeco-oral route | 1-3 days | Nonbacterial cause of diarrhea in infant and children, Vomiting, watery diarrhea fever and abdominal pain leading to dehydration. | stool | ELISA(Antibody), Electron Microscopy, PCR(RNA) | No | Live attenuated |
| 9 | Polio | Size: about 28 nm Nucleic Acid: Envelope: Antigen: VP1, VP4, C, D | Ingestion of contaminated food or water | About 10 days | Fever, malaise, headache, drowsiness, constipation, sore, throat, nonparalytic and paralytic poliomyelitis, Encephalitis | Pharyngeal aspirations and stool | Culture: Primary monkey kidney cell, HeLa and Hep-2 Electron microscopy: Virus particle | No | Salk’s killed polio vaccine, Live attenuated oral polio vaccine |
| 10 | Rabies | Size: 76-175 nm Nucleic Acid: -ssRNA Envelope: Present Antigen: NS, N, L | Bites of rabid dog, cat, rat etc. | 10 days to 3 months | Wounds on face and neck, fever, malaise, headache, photophobia, nausea, vomiting, sore, throat, encephalitis, (in 80%), paralytic (in 20%) | Saliva, cornea impression smear or skin biopsy, brain and skin tissue | Detection of antigens: Rapid direct, Immunofluorescence test using monoclonal antibody. Culture: Hamster, mouse cell lines, CNS inoculation of mice. Serology: Immunofluorescence or Neutralization test (Antibody) | Favipiravir | Neural Vaccines: Semple vaccine, β propiolactone vaccine. Non Neural Vaccine: Human diploid cell vaccine, Rabies, vaccine, adsorbed, purified chick embryo cell vaccine |