Immunizations in the United States: Vaccines

00:00 Let’s start with a hepatitis B vaccine. This is the first vaccine given to children because it’s given almost immediately after birth. That first dose actually prevents disease in babies who are exposed to hepatitis B in utero. That’s why we start giving it early. We give a total of 3 doses. Generally a first dose, a second dose at between 1 and 2 months of age, and then a third dose after 6 months to a year but before 18 months. It is extremely effective and safe. It is incredibly important to give because hepatitis B is very common in the United States and a major cause of both hepatitis and liver cancer. The rotavirus vaccine is given at 2, 4 and 6 months and it’s an oral vaccine. Rotavirus is a major cause of pediatric death worldwide and in the United States, prior to this vaccine, it was a major cause of hospitalization especially in the spring months in little children who are getting dehydrated from gastroenteritis. A previous version of this vaccine was on the market and then was taken off when they discovered that very rarely it could cause intussusception. The new rotavirus vaccine was designed after what was the largest randomized controlled trial in the history of the world.

01:26 At that time, they did a huge study and showed that this new version is less likely to cause intussusception and is safe and very effective in children. Remember though, this vaccine is really only effective for 2 years. That’s okay though. In older people, rotavirus is just an annoying enterovirus. It causes some vomiting and some diarrhea and then you get better.

01:51 It’s in those little children where they really get in trouble. So, by creating a live vaccine that works for a couple of years, you’re effectively preventing death and hospitalization. So, this has dramatically reduced diarrheal hospitalizations in the United States. There are 2 versions of this: one needs 2 doses, the other needs 3. Whether using 1 or the other depends on marketing and a number of other things. Okay, let’s go to the DTAP vaccine. This is an extremely safe and effective vaccine. Generally, we treat with this vaccine at 2, 4 and 6 months then again between 15 and 18 months and then again between 4 to 6 years. For tetanus, we need to continue to give boosters throughout life. For the pertussis, we also like to give the booster in the teen years, so boosters tend to happen throughout life mostly though for the tetanus. When children are less than 7 years of age, we give the DT acellular pertussis vaccine. When they’re over 7 years, we give TDAP. It doesn’t really matter so much that we understand this but remember the A stands for acellular pertussis. This is a protein derived vaccine and this was created because of concerns about the cellular vaccine that was given previously many years ago. The HIB vaccine is one of the truly great inventions of our lifetime. The HIB vaccine is given at 2, 4 and 6 months, and then lastly at either 12 to 15 months. It is extremely safe and effective and since the introduction of this vaccine, there is virtually no Haemophilus influenza B left in the United States. HIB or Haemophilus influenza B was a major cause of pneumonia, meningitis, severe infections of the skin and septic shock. So, this was a really bad disease and it’s virtually eradicated by this vaccine such that we really only see this in people traveling back from endemic areas. The pneumococcal PCV 13 valent vaccine was shown to be reducing hospitalization for pneumonia and meningitis in children in the United States. Children who receive this vaccine are less likely to get it. It’s given at 2, 4 and 6 months and again between 12 and 15 months.

04:26 This also reduced rate of ear infections. It used to be a 7 valent vaccine and the number of valencies have increased to cover more different serotypes of pneumococcal disease. This vaccine is updated periodically to cover those diseases caused by Pneumococcus that are particularly severe, say, complicated pneumonia. One thing that you should know about this vaccine is that it has a high rate of causing fever after administration. That doesn’t mean it’s not effective or it’s causing an infection, it’s just a febrile response to the vaccine. It’s transient and mild but it’s common, as high as 10%. So, you should warn families after receiving this that their child is likely to have a fever after administration. Moving on to the polio vaccine. We don't give the oral polio vaccine any more in the United States though it is used in some endemic areas where they’re having a hard time administering the inactivated polio vaccine, which is a shot.

05:29 So, the oral polio can rarely cause cases of polio itself. That’s why we’ve moved on to the IPV vaccine in the United States. It’s given at 2, 4 and then anywhere between 6 and 18 months and then again at 4 to 6 years. Unlike the OPV, the IPV does not cause polio. Remember, polio was a major cause of paralysis in children. Celebrities like Itzhak Perlman had it and were paralyzed afterwards. It’s important that we prevent polio because paralysis can be so horribly impactful in children. Moving on, measles, mumps and rubella. This is a combination vaccine that attacks both measles, mumps, and rubella. The vaccine is extremely safe and effective.

06:26 Measles can be lethal or cause severe brain disease even years after the child gets their first case of measles. That’s called subacute sclerosing panencephalitis. Outbreaks of measles still happen in the US, mostly in areas of low vaccination. So, it’s important for children to get this vaccine. They generally get it between 12 and 15 months and then again at 4 to 6 years. Rubella is a disease that is pretty mild but if a woman gets it for the first time while pregnant, the baby can get severe congenital deformations. They can have horrible problems. Mumps is a cause of of parotitis and orchitis in children. So, rubella, intrauterine birth defects, and mumps, parotitis and orchitis. Let’s move on to the chickenpox vaccine, which is also known as the varicella vaccine.

07:24 It’s given between 12 and 15 months and then again in 4 to 6 years just like the MMR. Most people think of varicella as a benign disease. When I was a kid, we used to have chickenpox parties, so that your kids could get it earlier knowing that earlier children get the disease, the more mild it is but chickenpox parties have been shown to cause significant illness. This is because actually varicella caused about 10,000 hospitalizations a year and 150 deaths per year in the United States. That was prior to vaccination. Now, we virtually never see chickenpox anymore. This vaccine has been very effective at saving lives. Children with varicella are also susceptible to severe bacterial infections like sepsis and cellulitis, and that’s part of why this has been so effective. It can prevent pneumonia, it can prevent encephalitis. Let’s move on to hepatitis A. Hepatitis A is a known cause of hepatitis in children. It’s spread by the fecal-oral route just like hepatitis E, which is much less common. Generally, we used to give hepatitis A for only children who are traveling to endemic areas but now it’s ubiquitously given in the United States. It’s typically 2 vaccines given 6 to 18 months apart.

08:49 The HPV vaccine is given as two doses series of HPV vaccine, on a schedule of zero and 6 to 12 months to all adolescence age 11 or 12 years.

09:01 We generally started before children are going to be sexually active.

09:04 It's more effective if it's given prior to a person actually obtaining HPV through sexual activity.

09:12 For person initiating vaccination at age 15 years or older, the recommended immunization schedule is three doses of HPV vaccine at zero, 1 to 2, and 6 months. It's effective at preventing cervical cancer which is top killer of young women and older women who have been infected with this virus.

09:31 It also effective at preventing penile cancer, but that is very rare.

09:37 Primarily, it's given to boys because they are a reservior to the virus when girls get it.

09:44 The meningococcal vaccine is very effective at preventing meningococcal meningitis and sepsis, which is an unusual cause of death, but this vaccine is very benign and very effective.

09:57 Meningococcus, remember, is extremely infectious.

10:01 It’s implicated commonly in outbreaks on college campuses.

10:05 You probably heard a news report of a patient who gets meningitis and everyone gets very afraid.

10:09 That’s because meningococcus is a killer and it can spread very rapidly.

10:14 This vaccine is effective at preventing the disease.

10:18 It’s an optional vaccine.

10:20 Children don’t have to get it but typically we give it to them around the age of 11 through 12 with a booster dose at 16 years.