Haemophilus Type B
Haemophilus influenza is a bacterium, which, despite its name, is entirely different from the viruses that cause influenza (the common flu). Before vaccination, Haemophilus influenzae type B (Hib) was the most common cause of childhood bacterial meningitis, killing 600 American children every year and leaving others deaf, mentally retarded, or epileptic. It is rarely troublesome for adults, although it can be dangerous for anyone with chronic lung disease and those susceptible to infections.
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| This is a gram stain of spinal fluid from a person with meningitis. The rod-like organisms seen in the fluid are Haemophilus influenza, one of the most common causes of childhood meningitis (prior to the widespread use of the H. influenza vaccine). The large red-colored objects are cells in the spinal fluid. A vaccine to prevent infection by Haemophilus influenza (type B) is available as one of the routine childhood immunizations (Hib), typically given at 2, 4 and 12 months. |
Vaccine for Haemophilus Influenzae Type B
Three equally effective inactivated bacterial vaccines are available for Haemophilus influenzae type B (called Hib vaccines). All children under five should be vaccinated against Haemophilus influenzae. The vaccine is administered as an injection at two and four months. Depending on the vaccination preparation, a third in the series is administered at six months. A booster is required at some time between 12 and 15 months of age.
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Click the icon to see an image of Hib immunization. |
In children older than 15 and 18 months, the Hib and DTaP vaccines are being combined in a single injection. Of note: evidence suggests that in infants, this combined vaccine using acellular pertussis (the current DTaP standard) is less effective in protecting against Hib than one that uses the older form with whole cell pertussis. The booster at one year should help maintain protection, however.
The Hib vaccine may benefit older people who have had splenectomies or illnesses that put them at risk for pneumonia, including sickle cell disease, leukemia, and HIV infection.
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Click the icon to see an image of sickle cells. |
Side Effects of Haemophilus Influenzae Type B Vaccine
Side effects of the Hib vaccine include redness and pain at the injection site, moderate fever, and, in rare cases, weakness, nausea, and dizziness.
Important Information on Vaccines for Smallpox
Vaccination against small pox used to be routine in the US until 1972, and most older Americans bear the telltale small round smallpox vaccination scar on their upper arms. Immunity may last 10 years or longer. The last case of smallpox, a highly contagious and deadly disease caused by the variola virus, occurred in a laboratory worker in the UK in 1978.
However, the growing threat of bioterrorism has raised fears that smallpox could be used as a biological weapon, and in 2002 the US government issued plans for vaccinating every citizen against the disease in the event of an outbreak. The vaccination, however, carries some risks. Currently, then, vaccination continues to be recommended only for laboratory workers and scientists who work with the virus.
If an outbreak occurs, guidelines from the Centers for Disease Control and Prevention call for a so-called "ring vaccination" approach. This involves identifying anyone who comes into contact with an infected person and vaccinating them and their contacts with a single dose of vaccine. This includes people of all ages and even those at risk for vaccine complications. The vaccine may work even if given within the first few days of infection.
Those at increased risk of vaccine complications but who should still be immunized if they are actually exposed to an outbreak include the following:
- Children younger than a year. About 42 infants out of a million will develop brain swelling that may result in retardation or death. A severe, body-wide rash may also occur, especially if children touch the vaccination site.
- Pregnant women. There is a small risk of miscarriage or premature delivery, although smallpox itself in pregnant mothers has more serious implications.
- People with skin conditions, particularly eczema. They may develop a widespread blistering rash called eczema vaccinatum, fatal in 1% to 6% of cases, and should not be vaccinated unless they've been exposed to the disease. They should also avoid others who have been vaccinated until those persons' vaccination scabs heal and fall off. People with non-chronic skin conditions such as allergic rashes, severe burns, or chickenpox may be vaccinated once their skin condition clears up.
- People with suppressed immunity due to HIV, organ transplants, high-dose steroids, cancer chemotherapy, or other conditions.
- Should a severe rash or other complication develop, patients should notify their doctors immediately. Two investigational medications, vaccine immune globulin (derived from the blood of people who have been vaccinated against smallpox) and an antiviral drug called cidofovir (Vistide), may be administered intravenously in the hospital should serious complications arise.
- In the event of an outbreak, current plans specify that vaccination against smallpox will remain voluntary, although unvaccinated people who are exposed to the disease may be quarantined for 18 days to help contain the spread of disease.
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Less Common Vaccinations
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Disease
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Who Should be Vaccinated
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Side Effects and Comments
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Rotavirus
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Rotavirus is the most common cause of diarrhea, cramps, and vomiting in infants, and affects about 3.5 million children in the US each year. As many as 80% of small children become infected with the virus. Although most cases in this country are mild, more than 50,000 American children are hospitalized and as many as 125 die from severe diarrhea every year. Worldwide the virus can be devastating, causing up to one million infant deaths annually. There is also some strong evidence that the virus may lead to childhood diabetes.
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An oral vaccine (Rotashield) has been withdrawn after reports of a severe and even life-threatening condition called intussusception following use of the vaccine. Intussusception occurs when the bowel slips inside itself like a telescope and obstructs the intestine. The risk was very small and occurred within a week or two of the vaccination. Any child who previously had the vaccination no longer incurs any increased risk. Preliminary reports suggest that newer rotavirus vaccines may be highly effective in preventing infection among infants, although more research is needed to confirm these findings and to determine its safety record in a large number of children. The association between diabetes and the virus itself raises some alarm that the vaccine may also increase the risk in children who are genetically susceptible to diabetes type 1.
Nevertheless, because this is a deadly virus for many children worldwide, international groups believe that the few cases of intussusception does not warrant withdrawing its use at least for countries where the infection is so common and deadly.
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Click the icon to see an x-ray of intussesception. |
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Rabies
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Anyone should be given the rabies vaccine who is exposed to secretions of an animal suspected of having rabies or to bats, whether or not there are indications of rabies. Exposed individuals should also receive immune globulin unless they were previously vaccinated. Veterinarians and animal handlers should be vaccinated. This does not eliminate the need for treatment if they are exposed to rabies, but it reduces the intensity of the treatment.
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Pain, redness, and swelling at the injection site. Headache, nausea, stomach pain, muscle aches, and dizziness. Allergic response, which can occur after the first shot and as long as 21 days after a booster shot. Rare cases of neurologic disorders that cause pain and paralysis in the legs and arms, which clear up in about 12 weeks.
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Click the icon to see an image of rabies. |
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Plague
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Veterinarians and assistants in the western US or anyone who works with potentially plague-infected animals; travelers to developing countries where outbreaks have occurred.
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Not wholly protective; may only lessen severity of the disease. Preventive antibiotics needed for anyone exposed. Side effects include headache, malaise, fever, swollen lymph nodes. Occasionally, non-infected abscesses. Allergic reaction, particularly in those sensitive to beef, soy, milk, and phenol.
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Anthrax
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Military personnel and vaccine researchers, as well as people who work with imported animal hides, furs, bone meal, wool, animal hair (especially goat hair), and bristles.
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Click the icon to see an image of cutaneous anthrax. |
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Appears to be safe and effective, even after exposure, but requires six shots over 18 months and testing is ongoing. Up to half of recipients develop temporary soreness, and some develop fever.
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Adenovirus
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Military personnel.
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Vaccine given orally for the prevention of respiratory illness.
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Yellow Fever
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Travelers to developing countries where outbreaks have occurred, currently parts of Africa and Central and South America. Residents of these areas, particularly children.
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Vaccinations safe and effective for the prevention of jaundice and kidney and liver failure. Anaphylactic reactions in those allergic to eggs. Very rarely, may cause a potentially fatal illness resembling yellow fever, with fever and diarrhea, particularly in seniors. Lower immunity when given with cholera vaccine; the vaccines should be given three weeks apart.
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Cholera
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Travelers to developing countries where outbreaks have occurred.
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Recently developed vaccines (Dukoral, Mutacol) are more effective than previous ones, which provided little protection. Not recommended or available, however, in the US.
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Typhoid
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Travelers to developing countries where outbreaks have occurred.
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Oral vaccines include: (Ty21a, Vivotif). The oral vaccines are not effective against parathyroid fever.
One-shot vaccine (Typhim Vi). Can be taken as early as two weeks before travel. Vi-rEPA is a newer injected vaccine that is safe in children and may be more effective-than other vaccines to date.
No vaccine is 100% effective, and the response tends to be lower in older people.
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Tuberculosis
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Individuals exposed to infected people.
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Bacille Calmette-Guerin vaccine has been the standard vaccine, but its effectiveness has been questioned. No longer recommended in US except for certain high-risk children.
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Meningitis caused by meningococcal bacteria
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People exposed to single cases or outbreaks, including some freshmen college students living in dorms; travelers to developing countries where outbreaks have occurred; patients with problems in the spleen.
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Vaccines are available against four subtypes of meningococcal bacteria but not for serogroup B, which causes up to 40% of meningococcal disease in the US. Among young people, fatalities have been higher in 15- to 24-year-olds than those younger than 15.
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Click the icon to see an image of tuberculosis. |
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