The common cold can be described as an infection of the higher reaches of the respiratory tract, or in other words the throat, the nasal passages and the nose. It is interesting to note that there are over two hundred different virus’ that can presently cause the common cold, but the main culprit in adults is the rhinoviruses, of which there are a hundred different strains and are classified as nose virus’.

When an individual becomes affected by a cold, the symptoms usually show up around two days later and these include a sore throat, a runny nose and sneezing. Later symptoms can consist of watery eyes, headache, muscle aches, stuffed nose, and a general feeling of being unwell. The symptoms of a cold can last anywhere from two to seven days but in some cases may even last up to two weeks.

Common Cold

People who have a common cold may find that is accompanied by bronchitis, laryngitis, an ear infection or with those who suffer from asthma, a worsening of the condition. Common cold infections are so prevalent that it is estimated that an adult will suffer between two and five colds each year. Because of this, the condition is the leading cause of people missing work days through illness.

Contrary to belief, colds are actually not very contagious when compared to other infections. Prolonged and close contact is required for the virus to spread and it must get into the nose for there to be infection.

A headache involves having mild to severe pain in a specific, or many, areas of the head or back of the neck. Countless “types” of headache exist, all caused by a variety of reasons, and although they can be painful and rather annoying, they are, for the most part, not a sign of a serious disorder and in most non-chronic situations can be treated and relieved by medicines.

Although there is no single cause of a headache, several causes have so far been identified by the medical community and these can fall into two main categories – tension headaches and migraine headaches. Tension headaches are the result of contraction of the neck and head muscles and are the most common type of headache, accounting for nearly seventy percent of cases. Some causes of muscle contraction linked with tension headaches include stress, fatigue, eye strain, poor posture, hormonal changes, and alcohol or tobacco use.

Migraine headaches occur when blood vessels located in the neck and head constrict, which therefore leads to decreased blood flow in them. Symptoms of migraine include a throbbing pain usually on one particular side of the head, along with a feeling of nausea and sensitivity to sound or light. Migraines are usually chronic and affect more women than men

Headache

Although for the most part headaches are not a sign of anything sinister, as mentioned above, there are certain symptoms that need to be looked at by a doctor or physician immediately. These include a sudden onset of headache accompanied by vomiting or nausea; recurring headaches which are accompanied by memory issues, tiredness and difficulty in concentrating; neck stiffness accompanied by high fever; fits; vision irregularities, i.e. light flashes; trouble controlling, or loss of feeling in, the limbs; and difficulty in communicating while being tired and apathetic.

First of all we should try and explain what influenza (flu) is. There are three main types: A, B and C, with B and C only infecting humans and influenza A being able to infect humans, animals and birds. The surface of each influenza A virus contains two types of protein, neuraminidase (N), of which there are nine types, and haemagglutinin (H), of which there are sixteen types. Consequently, there are lots of sub-strains of the influenza A virus and they are given names depending on the type of proteins found on the surface. Examples of these sub-strains could be H1N1, H1N2 and H2N3.

Another characteristic of the A strain is that it has the ability to produce new strains – in other words, mutate. It is as these new strains occur that new types of flu are discovered.

Bird flu is a strain of influenza A that affects birds, of which all species can be affected. Whereas wild birds can carry the disease when they migrate, they don’t usually become ill with it whereas poultry birds like turkeys and chickens do become ill. The virus spreads easily between these birds.

Bird Flu

It is the H5N1 virus that is causing all the problems with humans at the moment. This strain has affected birds for almost half a century, but it mutated back in 1997 in the Far East and spread to humans. As of yet this strain of the virus cannot be transferred from human to human, only from bird to bird or sometime bird to human.