Could A New Typhoid Vaccine End The Most Misdiagnosed Disease In Nigeria?
Editor’s Note: This week’s Thought Leadership on Health Series comes from Pharmacist and Public Health Specialist Chijioke Nwosu. He writes about the exciting release of a new typhoid vaccine approved by the World Health Organisation that could prevent typhoid fever in children and also reduce the misdiagnoses of fevers in Nigeria.
-By Chijioke Nwosu
“Typhoid fever” has long been recognized as one of the most diagnosed diseases in Nigeria. The challenge is that when diagnosed properly, typhoid fever is actually a life-threatening infection caused by the bacterium Salmonella Typhi. It is usually spread through contaminated food or water, and symptoms, including prolonged fever, fatigue, headache, nausea, and abdominal pain are very similar to those of the most common cause of fever in Nigeria — malaria.
The misdiagnosis of such a common clinical syndrome can lead to so many harmful outcomes. One is the unnecessary consumption of antibiotics by the individual misdiagnosed. Another is, the correct diagnosis can be missed — and this could be something more serious such as Lassa fever. Apart from the impact to the individual, there is also the impact to the community. The more unnecessary antibiotics are prescribed, the higher the risk of emergence of resistance to antibiotics, and very soon, we run the risk of not being able to treat even the most common infections!
That’s what makes the prospect of a new vaccine to prevent Typhoid fever so exciting for us in Nigeria. Vaccines have been described as the greatest innovation in modern times; without vaccines millions of people would probably have died from infectious diseases over the last few decades. Still, for a few years now, experts have become concerned that the rate of innovation and invention to bring new tools — especially new drugs and vaccines for infectious diseases- is slowing down. In countries around the world, vaccines are delivered to children through immunisation programmes that have standard schedules detailing what vaccines new born babies and infants are supposed to get and at what age, with most of these being modelled on the World Health Organization (WHO) recommendations.
Over the past twenty years or so, quite a number of new vaccines have become available. Countries that can afford to immediately add this to their immunisation schedules — thus improving the protection of their citizens from infectious diseases. However, a major drawback to their being included on publicly funded immunisation programmes in many countries has been their high cost when compared to the older and more established vaccines. Gavi, a global Vaccine Alliance, has enabled access to new and underused vaccines for children living in many of the world’s poorest countries, but some vaccines such as the HPV vaccine have remained mostly inaccessible to children in Africa. As a result, parents have often had to pay out-of-pocket for such vaccines or simply have their children do without them thereby leaving them at risk of infections such as typhoid and pneumonia.
However, in January 2018, some heart-warming news for children broke. The World Health Organization (WHO) approved a new typhoid vaccine for use globally. This is a big deal for several reasons. First of all, this is the first and so far, the only typhoid vaccine that can be used in children from the age of 6 months. Currently available typhoid vaccines can only be used in children over two years old. Also, and most importantly, it can be given as a single dose with no need for a booster because it confers long-lasting immunity.
Even more interesting is the fact that this new vaccine will be available at a cost far cheaper than any of the previously available vaccines against typhoid. According to currently available information, a dose would cost $1.50 or N540, when purchased by developing countries and will drop to $1 or less a dose if international donors purchase more than 100 million doses. Very importantly as well, the results of the study preceding the WHO approval of the vaccine show it to be about 87% effective in preventing typhoid fever.
What does all of this mean for us here in Nigeria? First, it means that we can now offer our infants protection against typhoid fever earlier, at 6 months of age, instead of the current age of 24 months on the national immunisation schedule. Even though the current schedule offers the currently available typhoid vaccine, the high cost means that many centres don’t offer it and even where they do, clients may be required to pay out-of-pocket for it.
The major risk factors for the transmission of typhoid fever are unhygienic conditions, poor access to clean drinking water and poor access to proper toilet facilities. These are circumstances that still exist widely in Nigeria.
Modern lifestyles also mean that infants are exposed to day-care centres and preschool much earlier than was previously the case, thus increasing the chances of them getting infections. It is therefore extremely important to offer them the protection they need as their own immune systems develop gradually. Children are especially susceptible, but the currently licensed vaccines do not confer lasting immunity in children, and/or come in inappropriate formats.
This new vaccine could be a real game changer in tackling typhoid fever, eliminate the most commonly misdiagnosed disease in Nigeria, reduce the risk of antimicrobial infection and save millions of children. It is hoped that the National Primary Healthcare Development Agency (NPHCDA) and the Ministry of Health will jump on this moving train before it leaves the station, so that our infants and children will not be denied the right to a healthy childhood and indeed the chance to survive into adulthood. Once introduced into the schedule — the next challenge becomes actually delivering the vaccine to children that need it.