HEPATITIS B

DEFINITION: Hepatitis B is a viral disease that affects the liver. Adults who get hepatitis B usually recover. However, most infants infected at birth become chronic carriers i.e. they carry the virus for many years and can spread the infection to others. In the year 2000, there were an estimated 5-7 million cases of acute hepatitis B infection and more than 521, 000 deaths from hepatitis B related disease.

HOW HEPATITIS B SPREADS

The hepatitis B virus is carried in the blood and other body fluids. It is usually spread by contact with blood in the following ways.

* Through an unsafe injection or needle stick. Unsterilized needles or syringes can contain hepatitis B virus from an infected person, for example from a patient or a needle user.

* Transmission of the virus by mothers to their babies during the birth process, when contact with blood always occurs.

* Transmission between children during social contact through cuts, scrapes, bites and scratches.

* Transmission during sexual intercourse through contact with blood or other body fluids.

SIGN AND SYMPTOMS OF HEPATITIS B

The incubation period averages six weeks but may be as long as six months.

Infection in young children usually is asymptomatic. However, a large proportion of children may become chronic carriers compared to adults. People who do not show symptoms may feel weak and may experience stomach upsets and other flu-like symptoms. They may also have very dark urine or very pale stools. Jaundice is common (yellow skin or a yellow colour in the white of the eyes). The symptoms may last several weeks or months. A laboratory blood test is required for confirmation.

Most acute infections in adults are followed by complete recovery. However, many children become chronic carriers. People who recover from acute hepatitis B (and who do not become chronic carriers) are protected from becoming infected again throughout their lives.

COMPLICATION OF HEPATITIS B

A small portion of acute infections can be severe and lead to death. The most serious complications, including chronic hepatitis, liver cirrhosis, liver failure and liver cancer occur in people with chronic infection.

TREATMENT OF HAPATITIS

There is no treatment for the acute condition. Supportive treatment is indicated. In chronic infection the disease can sometimes be stopped with medications.

PREVENTION OF HEPATITIS

It is recommended that all infants receive three doses of hepatitis B vaccine during the first year of life. More recently, some countries have been using a combination vaccine that includes vaccines for diphtheria, tetanus, pertussis, hepatitis B (hepB), and sometimes Haemophilis influenza type b (hib). Programmatically, it is usually easiest if the three doses of hepatitis B vaccine are given at the same time as the three doses of DPT. In countries where hepatitis B is highly endemic, where feasible, a birth dose of hebB is included in the schedule to prevent perinatal hepatitis B infection,.

Some countries also recommended immunizing adolescents, health workers and other risk groups.

HAEMOPHILUS INFLUENZAE type b (Hib)

DEFINITION: Haemophilus influenza type b (Hib) is one of the six related types of bacterium. In 2000 H. influenza type b (Hib) was estimated to have caused two to three million cases of serious disease, notably pneumonia and meningitis and 450000 deaths in young children.

HOW HAEMOPHILUS INFLUENZAE SPREAD

The Hib bacterium is commonly present in the nose and throat. Bacteria are transmitted from person to person in droplets through sneezing, coughing. Infected children may carry Hib bacteria without showing any signs or symptoms of illness, but can still infect others. The risk of disease is highest for children between six months and two years of age.

SIGN AND SYMPTOMS OF Hib

Pneumonia and meningitis are the most important diseases caused by Hib bacteria. In developing countries, pneumonia is more common than meningitis in children with Hib disease. Hib disease should be suspected in the case of any child with signs and symptoms of meningitis or pneumonia.

COMPLICATION OF Hib

Children who survive Hib and meningitis may develop permanent neurological disability, including brain damage, hearing loss and mental retardation. 15% to 30% of children who survive Hib disease are at risk of these disabilities. 5% to 10% cases of Hib and meningitis are at risk of dying.

TREATMENT OF Hib

Hib disease can be treated with specific antibiotics.

PREVENTION OF Hib

Several Hib conjugate vaccines are available. All are effective when given in early infancy, and have virtually no side effects except occasional temporary redness or swelling at the injection site. To reduce the number of injections, Hib is sometimes given in combination vaccines, DPT-hepB+Hib.