Author: admin

Human respiratory syncytial virus (RSV) is a virus that causes respiratory tract infections. It is the major cause of lower respiratory tract infections and results in many hospital visits during infancy and childhood.

In temperate climates there is an annual epidemic during the winter months. In tropical climates, infection is most common during the rainy season. In the United States, 60% of infants are infected during their first RSV season, and nearly all children will have been infected with the virus by 2–3 years of age. Among those infected with RSV, 2–3% will develop bronchiolitis and need professional care.

Natural infection with RSV induces protective immunity which wanes over time—possibly more so than other respiratory viral infections—so people can be infected multiple times. Sometimes an infant can become symptomatically infected more than once, even within a single RSV season. Severe RSV infections have increasingly been found among the elderly.

For most people, RSV produces only mild symptoms, often indistinguishable from common colds and minor illnesses. The Centers for Disease Control consider RSV to be the "most common cause of bronchiolitis (inflammation of the small airways in the lung) and pneumonia in children under 1 year of age in the United States". Other RSV symptoms common among infants include listlessness, poor or diminished appetite, and a possible fever.

Recurrent wheezing and asthma are more common among individuals who suffered severe RSV infection during their first few months of life. If RSV infection sets up a process that leads to recurrent wheezing or whether those already predisposed to asthma are more likely to become severely ill with RSV has yet to be determined.

For some children, RSV can cause bronchiolitis leading to severe respiratory illness that requires hospitalization and in rare cases, can cause death. This is more likely to occur in patients that are immunocompromised or infants born prematurely.

Rabies is a viral disease that causes acute encephalitis (inflammation of the brain). It is zoonotic (i.e., transmitted by beasts), most commonly by a bite from an infected subject. Roughly, ninety-seven percent of human rabies cases come from dog bites.

The rabies virus travels to the brain by following the peripheral nerves. The incubation period of the disease is usually a few months in humans, depending on the distance the virus must travel to reach the central nervous system.

The time between infection and the first flu-like symptoms is normally two to twelve weeks, but can take as long as two years. Once they appear, the symptoms expand to slight or partial paralysis, cerebral dysfunction, anxiety, insomnia, confusion, agitation, abnormal behavior, paranoia, terror, hallucinations, progressing to delirium. Producing large quantities of saliva and tears coupled with an inability to speak or swallow is typical during the later stages of the disease. This can result in hydrophobia, where the patient has difficulty swallowing because the throat and jaw become slowly paralyzed, show panic when presented with liquids to drink, and cannot quench their thirst.

Once the rabies virus reaches the central nervous system and symptoms begin to show, the infection is effectively untreatable and usually fatal within days. Death almost invariably results two to ten days after first symptoms. Remember that symptoms do not begin for 2-12 weeks after being exposed (bitten) to an infected animal. However, it is only prudent for us to tell you that Rabies can be a deadly disease. Please make a wise decision and if you feel you need medical attention, we encourage you to seek it.

The B19 virus, generally referred to as parvovirus B19 or sometimes erythrovirus B19, causes a childhood rash called fifth disease or erythema infectiosum, which is commonly called "slapped cheek syndrome". You can see why by the photo. The virus is primarily spread by infected respiratory droplets, but blood-borne transmission has been reported.

Fifth disease or erythema infectiosum is only one of several expressions of Parvovirus B19. Any age may be affected, although it is most common in children aged six to ten years. It is named due to being the fifth pink-red infectious rash to be described by physicians.

Infected patients with normal immune systems are contagious before becoming symptomatic, but usually not after. Once infected, patients usually develop the illness after an incubation period of four to fourteen days. The disease commences with fever and malaise while the virus is most abundant in the bloodstream, and patients are usually no longer infectious once the characteristic rash of this disease has appeared. Teenagers or young adults may develop the so called 'Papular Purpuric Gloves and Socks Syndrome'.

Fifth disease is also known for "lace-like" rashes on the arms, legs, torso, and back. These rashes can last for up to 5 weeks and are worse after sun exposure, exercise, or hot baths.

In adults (and perhaps some children), parvovirus B19 can lead to seronegative arthritis. Women are approximately twice as likely as men to experience arthritis after parvovirus infection. Possibly up to 15% of all new cases of arthritis are due to parvovirus. A history of recent contact with a patient and positive serology generally confirms the diagnosis. This arthritis does not progress to other forms of arthritis. Typically joint symptoms last 1–3 weeks, but in 10-20% of those infected, it may last weeks to months.

Although most patients have an arrest of erythropoiesis (production of red blood cells) during parvovirus infection, it is most dangerous in patients who have sickle cell anemia or hereditary spherocytosis, and are therefore heavily dependent on erythropoeisis due to the reduced lifespan of the red cells. This is termed "aplastic crisis" (also called reticulocytopenia) and is generally treated with a blood transfusion.

HPIVs (human parainfluenza viruses) are spread person to person by direct contact with infected secretions through respiratory droplets or contaminated surfaces or objects. Infection can occur when infectious material contacts mucous membranes of the eyes, mouth, or nose, and possibly through the inhalation of droplets generated by a sneeze or cough. HPIVs can remain infectious in airborne droplets for over an hour. HPIVs are ubiquitous and infect most people during childhood. The highest rates of serious HPIV illnesses occur among young children. Serologic surveys have shown that 90-100% of children aged 5 years and older have antibodies to HPIV-3, and about 75% have antibodies to HPIV-1 and -2.

Human parainfluenza viruses (HPIVs) are common causes of respiratory tract disease in infants and young children. Each of the four HPIVs have different clinical and epidemiologic features. The most distinctive clinical feature of HPIV-1 and HPIV-2 is croup (i.e., laryngotracheobronchitis or swelling around the vocal chords and other parts of the upper and middle airway). HPIV-1 is the leading cause of croup in children, whereas HPIV-2 is less frequently detected.

HPIV-3 is more often associated with bronchiolitis (swelling of the small airways leading to the lungs) and pneumonia. HPIV-4 is rarely detected and is less likely to cause severe disease; but it may be more common than once thought.

HPIVs can cause repeated infections throughout life. Re-infections are usually manifested by an upper respiratory tract illness (e.g., a cold, sore throat). HPIVs can also cause serious lower respiratory tract disease with repeat infection (e.g., pneumonia, bronchitis, and bronchiolitis), especially among older adults and patients with compromised immune systems. The incubation period (time from exposure to the virus to onset of symptoms) for HPIVs generally ranges from 2 to 7 days.

Human papillomaviruses (HPV) establish productive infections either in keratinocytes of the skin (outermost layer of the skin, causing warts) or in mucous membranes, as in the case of HPV. HPV is the most frequent sexually transmitted disease in the world!

These viruses are responsible for common warts, plantar warts, flat warts and possibly the cause of many skin tags. More than 30 to 40 types of HPV are typically transmitted through sexual contact and infect the anal-genital region. Some sexually transmitted HPV types may cause genital warts. Persistent infection with "high-risk" HPV types — different from the ones that cause skin warts — may progress to precancerous lesions and invasive cancer. HPV infection is a cause of nearly all cases of cervical cancer.

Over 120 HPV types have been identified and are referred to by number. Types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, and 59 are considered the "high-risk" sexually transmitted HPVs and may lead to the development of cancers and other diseases. Following is a list of various conditions/disease and their associated HPV.

• Common warts: 2, 7
• Plantar warts: 1, 2, 4, 63
• Flat warts: 3, 10
• Anal-genital warts: 6, 11, 42, 44 and others
• Genital cancers, Highest risk: 16, 18, 31, 45, Other high-risk: 33, 35, 39, 51, 52, 56, 58, 59, Possible high-risk: 26, 53, 66, 68, 73, 82
• Epidermodysplasia verruciformis: more than 15 types
• Focal epithelial hyperplasia (oral): 13, 32
• Oral papillomas: 6, 7, 11, 16, 32
• Oropharyngeal cancer: 16
• Laryngeal papillomatosis: 6,11

Although genital HPV types can be transmitted from mother to child during birth, the appearance of genital HPV-related diseases in newborns is rare. Perinatal transmission of HPV types 6 and 11 can result in the development of juvenile-onset recurrent respiratory papillomatosis (JORRP). JORRP is very rare, with rates of about 2 cases per 100,000 children in the United States. Although JORRP rates are substantially higher if a woman presents with genital warts at the time of giving birth, the risk of JORRP in such cases is still less than 1%.

At least 40 identified HPV types infect the genital tract. If a college woman has at least one different partner per year for four years, the probability that she will leave college with an HPV infection is greater than 85%. Condoms do not completely protect from the virus because the areas around the genitals including the inner thigh area are not covered, thus exposing these areas to the infected person's skin.

Because HPV is considered a precursor for cancer, preventative surgery for HPV can cause infertility and is completely unnecessary, even though it is what modern medicine advocates.