Levin Find articles by Bruce R. Wrote, modified and debugged the Berkeley Madonna program: Provided biological and epidemiological input:
Treating symptoms of the common cold has given rise in the United States to a multi-million dollar industry in over-the-counter medications.
Colds make the upper respiratory system less resistant to bacterial infection.
Secondary bacterial infection may lead to middle ear infection otitis mediabronchitis, pneumoniasinus infection, or strep throat. People with chronic lung disease, asthmadiabetes, or a weakened immune system are more likely to develop these complications. Transmission People with colds are contagious during the first two to four days of the infection.
Colds pass from person to person in several ways. When an infected person coughs, sneezes, or speaks, tiny fluid droplets containing the virus are expelled. If these are breathed in by other people, the virus may establish itself in their noses and airways. Colds may also be passed through direct contact.
If a person with a cold touches his runny nose or watery eyes, then shakes hands with another person, some of the virus is transferred to the uninfected person.
If that person then touches his mouth, nose, or eyes, the virus is transferred to an environment where it can reproduce and cause a cold.
In addition, cold viruses can be spread through inanimate objects door knobs, telephones, toys that become contaminated with the virus. This is a common method of transmission in childcare centers.
If a child with a cold touches his runny nose, then plays with a toy, some of the virus may be transferred to the toy. When another child plays with the toy a short time later, he may pick up some of the virus on his hands.
The second child then touches his contaminated hands to his eyes, nose, or mouth and transfers some of the cold virus to himself. Demographics Colds are the most common illness to strike any part of the body, with over one billion colds in the United States each year. Anyone can get a cold, although pre-school and grade school children catch them more frequently than adolescents and adults.
Children average six to ten colds a year. In families with children in school, the number can be as high as 12 per year. Women, especially those aged 20 to 30 years old, have more colds than men, possibly because of their closer contact with children.
Individuals older than 60 usually have fewer than one cold per year. Repeated exposure to viruses causing colds creates partial immunity. Causes and symptoms Colds are caused by more than different viruses. The most common groups are rhinoviruses and coronaviruses. Different groups of viruses are more infectious at different seasons of the year, but knowing the exact virus causing the cold is not important in treatment.
Once acquired, the cold virus attaches itself to the lining of the nasal passages and sinuses. This condition causes the infected cells to release a chemical called histamine.
Histamine increases the blood flow to the infected cells, causing swelling, congestion, and increased mucus production. Within one to three days the infected person begins to show cold symptoms. The first cold symptoms are a tickle in the throat, runny nose, and sneezing.
The initial discharge from the nose is clear and thin. Later it changes to a thick yellow or greenish discharge. Most adults do not develop a fever when they catch a cold. In addition to a runny nose and fever, signs of a cold include coughing, sneezing, nasal congestion, headachemuscle ache, chills, sore throathoarseness, watery eyes, tiredness, and lack of appetite.
The cough that accompanies a cold is usually intermittent and dry. Most people begin to feel better four to five days after their cold symptoms become noticeable.
All symptoms are generally gone within ten days, except for a dry cough that may linger for up to three weeks. When to call the doctor Colds make people more susceptible to bacterial infections such as strep throat, middle ear infections, and sinus infections.
People who have colds that do not begin to improve within a week or who experience chest painfever for more than a few days, difficulty breathing, bluish lips or fingernails, a cough that brings up greenish-yellow or grayish sputum, skin rash, swollen glands, or whitish spots on the tonsils or throat should consult a doctor to see to determine if they have acquired a secondary bacterial infection that needs to be treated with an antibiotic.
Children who have chronic lung disease, diabetes, or a weakened immune system—either from diseases such as AIDS or leukemia or as the result of medications, corticosteroids, chemotherapy drugs —should consult their doctor if they get a cold.Community-acquired pneumonia develops in people with limited or no contact with medical institutions or settings.
The most commonly identified pathogens are Streptococcus pneumoniae, Haemophilus influenzae, atypical bacteria (ie, Chlamydia pneumoniae, Mycoplasma pneumoniae, Legionella sp), and viruses. Symptoms and signs are fever, cough, sputum production, pleuritic chest pain, dyspnea.
In accord with our analysis, hundreds of patients with symptomatic influenza would need to be prophylaxed, NNP, to prevent a single case of secondary pneumococcal pneumonia, even in this model which assumes that asymptomatic influenza infection does not increase the susceptibility to bacterial colonization or transmission.
With a huge number of victims, 80 to million, since , the influenza is considered as one of the most pandemic diseases ever. There are three types of influenza virus: influenza virus A, influenza virus B, and influenza virus c.
These are a subtypes of the virus family orthomyx-oviride. In nearly all countries where human influenza infection is reported, the pandemic influenza A (H1N1) continues to be the predominant subtype among all influenza A viruses subtyped (% in North America region, AMR, 94% in EUR and 90% global).
Antifungal and antiviral agents. We review the relatively limited repertoire of compounds available for the treatment of fungal and viral infections.
Possible vaccines and antiviral drugs with the potential ability to control and prevent airborne transmission of influenza viruses could be further researched as avian viruses have been demonstrated to possess the ability to transmit between mammals and may one day result in another severe pandemic.