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Site author Richard Steane
The BioTopics website gives access to interactive resource material, developed to support the learning and teaching of Biology at a variety of levels.

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Viral diseases

i.e common (human) diseases caused by infection by a virus

Ebola virus section now moved to another independent file.
Disease -
Caused by
(Signs) and Symptoms
Control/
prevention
Spread by
Disease -
Common cold
(upper respiratory system infection) rhinovirus_3d_simulation (38K) Caused by
Rhinovirus (many forms)
and coronavirus (and others)
Image courtesy University of Melbourne
Signs and Symptoms:
Scratchy throat, sore throat, nasal congestion, runny nose, sneezing, (cough, fever) - more pronounced in young children
Control/
prevention
:
Cold medicines should relieve symptoms (lowering temperature, etc) but there is no vaccine
Spread by:
Airborne droplets (aerosols) from sneezes, coughs, etc or by contact -contagious for the first 2 to 3 days, usually not after the first week.
'
Disease -
Flu
(upper and occasionally lower respiratory system infection)
3d_influenza_transparent_no_key_full_180 (24K)
Caused by
Influenza virus

Image courtesy CDC
Signs and Symptoms:
Chill, fever, sore throat, muscle pains, headache, cough, fatigue, general discomfort
More serious than the (common) cold
Control/
prevention
:
  • Trivalent influenza vaccine (TIV) - needs reformulating each year as influenza virus evolves rapidly, and new strains quickly replace the older ones.
  • Antiviral drugs e.g. Tamiflu, Relenza) are quite effective.
  • Handwashing and disinfection of surfaces is also important.
  • Paracetamol may relieve symptoms e.g. fever and muscle aches.
Spread by:
Airborne droplets (aerosols) from sneezes, coughs, etc or by contact with contaminated surfaces
Disease -
Mumps mumps1874_lores (113K) Caused by
Mumps virus (a Rubulavirus)
Image courtesy CDC
Signs and Symptoms:
Swelling of salivary glands, headache, fever, inflammation of testes (more important in teenagers and adults)
Control/
prevention
:
Mumps vaccine (part of MMR and MMRV* vaccines)
Spread by:
Airborne droplets (aerosols) from sneezes, coughs, etc or by contact with surfaces

Very easily spread in university/college scenarios
Disease -
Measles
(also called rubeola, not to be confused with rubella) morbillivirus10707_lores (147K) Caused by
Morbillivirus
Image courtesy CDC
Signs and Symptoms:
Respiratory system infection, fever, cough, runny nose, red eyes, skin rash.
Control/
prevention
:
Measles vaccine (part of MMR and MMRV* vaccines)
Spread by:
Airborne droplets (aerosols) from nose and mouth, etc or by contact

Serious disease in some under-developed countries
Disease -
Rubella ("German measles") Rubella (36K) Caused by
Rubella virus
Signs and Symptoms:
Minor flu-like symptoms and rash but if a woman is pregnant it can cause deafness, eye abnormalities, and congenital heart disease in baby
Control/
prevention
:
Rubella vaccine (part of MMR and MMRV* vaccines)
Spread by:
Airborne droplet emission from the upper respiratory tract
Disease -
Chickenpox Varicella-zoster-virus (613K) Caused by
Varicella zoster virus
Also see below
Signs and Symptoms:
Skin rash, muscle pain, nausea, fever, headache, sore throat, pain in both ears, complaints of pressure in head or swollen face, and malaise in adolescents and adults
Control/
prevention
:
Varicella vaccine (part of MMRV* vaccines)
Spread by:
Airborne - coughing or sneezing or through direct contact with secretions from the rash.
Disease -
Shingles
Caused by
Varicella zoster virus reactivation after chickenpox infection - perhaps years before - virus travels down nerve to skin
Signs and Symptoms:
Painful, sensitive, tingling or burning skin, eventually turning into a rash of red spots, fever, headache and enlarged lymph nodes.
Control/
prevention
:
  • Antiviral medicines: acyclovir ACV (Zovirax)
  • Symptom control: Painkillers, calamine lotion against itching.
Spread by:
Shingles rash can spread chickenpox if touched so no sharing towels, swimming, or contact sports.
Disease -
(HIV/AIDS)
HIV (37K)
Caused by
Human immunodeficiency virus
Signs and Symptoms:
Progressive failure of the immune system allowing development of life-threatening opportunistic infections e.g. pneumonia and cancers
Control/
prevention
:
  • Use of condoms (protected sex)
  • (new) disposable syringes and needles
  • multiple antiviral treatment now much more effective at extending life expectancy, and pre-exposure prophylaxis reduces infectiousness
  • screening of blood and products
  • no vaccine
Spread by:
Transfer of body fluids: blood, semen, vaginal fluid, pre-ejaculate, or breast milk

Using non-sterile syringe needles (drug addicts or insecure health service)
Disease -
(HPV) HPV (36K) Caused by
Human papillomavirus
Signs and Symptoms:
Small genital and other warts: may be insignificant (both sexes)
- may lead to cancer within the reproductive system, especially cervical cancer in females (major cause of cervical cancer)
Control/
prevention
:
  • HPV vaccine - now administered to teenage girls in UK and USA - not effective against existing infections
  • condoms
  • microbicides
Spread by:
Sexual activity, including oral sex
Disease -
Oral Herpes
Genital Herpes

(other forms) herpes (8K) Caused by
Herpes simplex virus
Signs and Symptoms:
Blisters (cold sores) on lips, genitals (other parts of the body may be infected)
Control/
prevention
:
Condoms
antivirals: acyclovir ACV (Zovirax)
Spread by:
Skin-to-skin contact especially with active lesion or body fluid
Infection remains and can be reactivated (depending on health?)
Disease -
Norovirus
"winter vomiting bug"
norovirus (113K) Caused by
Norovirus
(Norwalk-like Viruses)
Signs and Symptoms:
Symptoms start suddenly within 1 to 2 days of being infected:
feeling sick (nausea)
being sick (vomiting)
diarrhoea
possibly
high temperature
(38°C or above)
headache
aching arms and legs
Control/
prevention
:
Stay off school or work until the symptoms have stopped for 2 days.
Also avoid visiting anyone in hospital during this time.

Rotavirus vaccination is available routinely on the NHS in the UK as part of the childhood vaccination programme for babies aged 8 weeks and 12 weeks.
Spread by:
Close contact with someone with norovirus
- touching surfaces or objects that have the virus on them, then touching your mouth
- eating food prepared or handled by someone with norovirus

Washing hands frequently with soap and water.
Alcohol hand gels do not kill norovirus.
* not normally given in UK

Things to research

How common is the common cold?

How much worse are smokers affected with colds than non-smokers?

(In the context of influenza) What is the difference between an epidemic and a pandemic?

What does H5N1 mean?

Avian (bird) flu

Swine flu

Past outbreaks of flu (often with geographical associations)

Death rates from these diseases in the western world and in developing countries.

Vaccination rates against these diseases in the westerm world and in developing countries.

Incidence of mumps before and after vaccine development (1967? and MMR 1988), and since 1988 when doubts about the MMR vaccine were raised by Andrew Wakefield - now discredited.

% coverage (immunisation) of population over this time

Find out if you have had the MMR vaccine (and the follow-up booster shot).

Measles - mortality in UK/ USA and in sub-Saharan Africa

There are many other human viral diseases.
Find out about one that has a name that starts with the same letter as your surname!


Other topics on this site

Ebola virus section Was part of this topic - now moved to another independent file.

HIV/AIDS Part of a topic on Cell recognition

Virus particles Contrasting viruses with cellular organisms

Web references

Measles cases at '18-year high'



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