Vaccination: Incomplete dose as good as none

By Joyce Nyakato

Vaccination protects your baby from various diseases such as measles, mumps and rubella. Immunisation is successful in nearly all cases. However, some children do not build up the immunity that the vaccine aimed to provide, the reason they suffer from diseases against which they were vaccinated. A booster dose, is therefore, given to ensure that the immunity builds. Joyce Nyakato writes:

Jane’s son was immunised against polio and TB at birth. She was asked to take him back after six weeks for his first shot against tetanus. Despite the nurses insisting on the importance of additional vaccinations, she did not heed to the advice.

Six years later, he was diagnosed with tetanus. Unable to swallow food and racked with pain, spasms often caused him to bite his tongue involuntarily and consistently. As a result, the doctors had to amputate his tongue as it was almost falling off. Despite having got one dose of the vaccine, he still suffered from tetanus, an infection of the central nervous system, caused by a  bacterial infection of open wounds.  Cases like this demonstrate the importance of completing the vaccination schedule.

According to Dr. Sabrina Kitaka, a consultant paediatric surgeon, even when a child gets the full dose of immunisation, it is important to have booster doses to boost child’s immunity. She says, particularly for tetanus, children should get a booster dose at the age of five, as this is around the time they start school.

Most children miss the full dose

According to a study conducted by Mulago Hospital School of Medicine Department, Paediatrics and  hild Health, only 36% of Ugandan oneyear olds are fully immunised. For the immunisation to be considered full, one has to complete the immunisation schedule, as  spelt out on the immunisation card.

Daphine Binta, the AAR business development manager in charge of healthcare, says the health card helps mothers take their children for vaccination as indicated on the immunisation schedule. In addition, health workers should go through the card with the mothers and tell them when to take their children back for immunisation.

Types of vaccinations

Dr. Jehosophat Byamugisha, the head of the obstetrics department at Mulago Hospital, echoes the same sentiments. He says when a woman gives birth, the baby should the BCG vaccine (for TB) and an oral polio vaccine. The mother has to return after six weeks for a post-natal check-up and during this visit, the baby receives an additional polio dose.

The diphtheria, whooping cough and tetanus (DPT) vaccine is administered alongside the Hepatitis B vaccine (HepB) and the HIB 2 meningitis vaccine. Parents are advised to take their children back for vaccination after 10 weeks and 14 weeks, respectively, for additional doses of DPT, HepB and Hib3 vaccines.

However, statistics reveal that only 59% of the women are likely to seek post-natal care, therefore, many children miss the complete dose of vaccination, rendering it useless.

The Hepatitis B has only been recently added to the list of free vaccines, so adults who missed out on the vaccination remain at the risk of suffering from the disease. However, one can still have the vaccination for the first time as an adult, as long as one tests negative for Hepatitis B. Binta says the Hepatitis B vaccine is administered in three doses. The second dose is given one month after the fi rst dose and the third dose should be received six months after the first dose.

Free immunisation

The United Nation’s Expanded Program on immunisation (UNEPI), under the Ministry of Health, offers about eight vaccines for free. These include vaccines for; tuberculosis, polio, measles, diphtheria, whooping cough, tetanus, Hepatitis B and cervical cancer.

Dr. Jessica Nsungwa, the assistant commissioner of child health, explains that the Ministry of Health is planning to avail free vaccination for the pneumonia vaccine (pneumococcal) in all health centres. The pneumococcal vaccine, goes for about sh100,000 and is administered in two doses alongside the DPT vaccine.

What is a vaccine?

According to Dr. Emmanuel Mugisha, the executive director of PATH Uganda, an NGO that implements vaccination, a vaccine improves immunity to a particular disease. It typically resembles a diseasecausing microorganism, often made from weakened or killed forms of the germ to wake up the anti-bodies, he says.

The germ stimulates the body’s immune system to recognise the agent as foreign, and destroy it. As the body builds immunity, children may get fevers, but these can be managed at home or by a doctor.

What is a booster dose?

A booster dose is a re-exposure to the immunising antigen. Boosters help in adding onto one’s immunity,” says Dr. Duncan Nduhura, a medical practitioner at International Hospital Kampala. Booster doses are intended to increase immunity against an antigen, after the strength of the vaccine is shown to be waning.

Kitaka explains that because vaccines are expensive, high-risk groups like children under fi ve years are given priority because they have low immunity. Adults do not get booster doses, except for the tetanus vaccine, which is given free to pregnant women and girls in the reproductive age. Children may also be given additional doses, irrespective of whether they have been immunised or not,” Nsungwa adds.

According to Dr. Emma Tenywa, an epidemiologist with World Health Organisation, when children do not receive the full dose of a vaccine, their immunity is compromised, putting them at risk of catching the disease in case of an outbreak. It is for this reason that the Government organises mass vaccinations for high-risk groups in case of disease outbreaks.

You can catch a disease you’ve been vaccinated for

When someone who was been immunised against a disease still suffers from it, this does not mean that the immunisation was ineffective. It actually protects the body from acquiring the serious form of the disease.

According to Dr. Imoko, BCG,  for instance, does not completely prevent children from developing tuberculosis, but insulates them against severe forms of tuberculosis. This is the same reason people are able to have latent (potentially existing, but not presently evident or realised) TB because their immunity keeps the disease at bay.

Similarly, the Rotavirus vaccine which, according to World Health recommendation in high risk areas, is administered orally in a two-dose schedule along fi rst and second doses of DPT, protects children from severe watery diarrhoea, often with vomiting, fever and abdominal pain.

In children, acute diarrhoea can lead to dehydration and may result in death. So, even if a child is vaccinated, it is possible for him to suffer from other forms of diarrhoea, which are less severe.  According to Binta if people suffer from measles when vaccinated, the immunity in their body usually can handle it and, therefore, manifests in a milder form.

“Many people confuse German measles with measles,” says Kitaka. German measles (rubella) and measles are caused by different viruses and have different vaccines, she adds. Measles is a much more severe disease. However, the biggest problem with rubella is exposure to the virus during pregnancy. If a pregnant woman develops rubella in early pregnancy, she is at high risk of getting a miscarriage, or having a baby with deafness, congenital heart disease, or mental retardation.

Boosters provided by government Nsungwa explains that the ministry covers booster doses for tetanus, and encourages both children and adults to get the vaccine, especially people who have had a cut, or an accident. However, the vaccine does not work when the disease has already progressed.

Instead, treatment is given. Usually, health workers vaccinate anyone who has been exposed to an infection, as a protective measure, regardless of whether they got their boosters or not. But girls, particularly those in the reproductive age as well as pregnant women are given a fivedose vaccine to prevent maternal and neonatal tetanus.

The ministry, however, does not cover booster doses, most notably the (MMR) vaccine for measles, mumps and rubella (German measles) recommended for the 15-month-olds, plus the DPT for school age-going children. Binta explains that ideally, most of the vaccines, under special circumstances, will require a booster at some point, except the chicken pox vaccine, which is recommended at the age of one and offers lifetime immunity.

Dr. Joseph Imoko, the national TB focal person in the World Health Organisation adds that a TB vaccine booster is needed to strengthen one’s immunity even when one got the BCG vaccine, especially for a country like Uganda, which is burdened by TB. A recent vaccine, which had been undergoing human trials failed. However, the BCG booster is sometimes recommended for people who are travelling. However, one needs to be tested for TB before they are given the vaccine, as it only provides protection and not a form of treatment.

According to Byamugisha, many young women have shunned the cervical cancer doses, after the fi rst round of vaccination, partly  due to the high costs. A dose costs about sh100,000 per dose. However, he says, while some of these vaccines may be so expensive, they help protect one from cervical cancer, which is far more costly to treat after the disease strikes. Some vaccines are not emphasised but may be required when one is travelling abroad, for instance the yellow fever vaccine. The yellow fever jab offers a 10- year immunity before one receives a booster.