Dr Joseph Ojonugwa Shaibu, a Molecular Virologist whose work is primarily on viruses at the Centre for Human Virology and Genomics of the Nigerian Institute of Medical Research (NIMR), Yaba, Lagos State, speaks in this interview with Sade Oguntola on the need for surveillance, determination of prevalent disease-causing organisms and preparedness for outbreaks in Nigeria. Excerpts:
HOW was the hepatitis B kit made? How about its uniqueness, given that we also have other hepatitis B test kits in use around the world?
The Nigerian Institute for Medical Research (NIMR) Hepatitis B version 1.0 kit (HBV qPCR kit 1.0) is a real-time PCR probed-based assay that runs on one channel with an internal control that runs on another channel. It is developed to detect and quantify the hepatitis B genotype that is circulating in our environment and globally. It is unique in that it is cheap and readily available.
One of the pushes of our Director-General, Professor Babatunde Salako, is that we should grow home solutions to our problems and we should be sure that it will help reduce costs for the public. This desire of his has led us to develop detection kits for COVID-19 (SCODA and SIMA), Lassa, yellow fever, and Monkey pox. He has been very supportive in providing funding for the processes that lead to these products. One thing that we leveraged in the course of developing the hepatitis B virus (HBV) kit was that we had repositories of HBV-positive samples and the globally approved standard system (Cobass, Roche) for the diagnosis of HBV; these greatly accelerated our internal validation process. For several years, we have been testing for this virus in our laboratory using the Roche platform. A lot of people come for hepatitis B testing every day, but several times, we run out of test kits and this elongates our turnaround time. That was how we came up with the quest to develop home-grown test kits that can compete well with the international standard.
How do you see this helping in stemming increasing cases of hepatitis B and its complications in Nigeria?
The hepatitis B test kit has basically two uses: detection and quantification of the hepatitis B virus. For detection (to ascertain if a person is positive to hepatitis B or not), it has 100 percent sensitivity and specificity, when compared with the Roche system. For patient management, you need to know the viral load and that is where the quantification comes in. Our test kit has a correlation coefficient of 91 percent when compared to that of the Roche platform.
Of course, there are other real-time PCR hepatitis B test kits available on the market. But a big challenge with these kits is the poor yield of the virus during the extraction process for testing, which ultimately affects the performance of the kit. Most laboratories use a spin column-based extraction process, which gives a low DNA yield for HBV. In our laboratory, we have an automated extraction system, which gave us a yield with a 260/280 ratio of 1.76. This works well with the kit.
However, we are aware that most laboratories within the country do not have such an extraction process in place; hence, in the second phase of this project, we are trying to optimise the NIMR Biotech DNA extraction kit to give a yield that matches what the automated system is currently yielding. This will be highly beneficial to the various laboratories that cannot afford the automated system. I can tell you that this hepatitis B test kit is going to be of great benefit for those requiring routine hepatitis B tests and monitoring of hepatitis B DNA, as it will greatly reduce the cost of testing.
Are there other test kits developed by the institute? Do you also have other test kits in the pipeline?
We had other kits. When COVID-19 came, we had one for COVID-19 detection and a lot of laboratories also use them for detection at a cheaper price, compared to what was obtainable with other test kits brought from abroad. We also developed test kits for Lassa fever, yellow fever and monkey pox. Our target is to develop detection kits for any disease that is of public health importance and has been declared a priority by the Nigeria Centre for Disease Control (NCDC) and World Health Organisation (WHO). We are working on PCR assays, serology assays and rapid detection kits for arboviruses. The rapid detection kits are to be taken to remote sites for preliminary screenings to initiate prompt management of infections.
If a problem and its source are not known, you cannot solve it. There are many infections that are circulating in our environment, causing a lot of diseases that are unknown. Because effective diagnosis and management are not there, they will keep recurring. This still boils down to the fact that we are short on diagnosis for a lot of pathogens that cause diseases circulating in our environment.
As such, at NIMR, we conduct surveillance on the majority of these infections that are of high fatality and of high priority in the country. Once we detect them, we try to sequence them to have genomic data that can later be used in the development of diagnostic tools, drugs and even vaccines. Data from other continents only indicates strains that are circulating on those continents, and they may be different from those circulating in Africa. So, drugs, diagnostics and vaccines manufactured based on the strains on those continents may not work effectively here in Africa. However, there is not enough research to produce this genomic data that covers Africa, especially Nigeria.
Back to a molecular surveillance study you carried out to investigate the burden and types of arboviruses in circulation in Nigeria, what were the viruses that you found?
That was one of the publications from my Ph.D. thesis on the molecular surveillance of arboviruses in Nigeria that was published in BMC infectious diseases. The surveillance done in four states in Nigeria was on viruses for Zika, yellow fever, dengue, rift valley and Chikugunya. These are priority infections transmitted by vectors that are common in our society, such as mosquitoes, especially the Aedes species. One of the unique things about these viral infections is that their clinical manifestations are similar to those of malaria and/or typhoid.
In many communities in Nigeria, you see many people coming down with sudden high fevers, but because there is no parameter to use to check its cause. Most times, it is concluded to be malaria or typhoid fever, and they give them malaria medication. But when the person is not recovering, he or she is left to his or her fate. If it results in death, they often attribute it to witches and wizards.
But it could well have been due to these other viruses that have high fatalities in chronic cases and spread quickly within a short period of time. By the time you begin to see a manifestation of high fever, one of the suspects is an arbovirus. Arboviruses are arthropod-borne viruses; the mosquito is an example of that.
Within the period of that study, we found no active cases of dengue fever, rift valley fever, zika, or chikugunya. But serology tests showed evidence of exposure to all these viruses in the four states. They had antibodies for these viruses. We were able to detect the yellow fever virus in active circulation in one of the states. The yellow fever was lineage III of the West African genotype based on molecular analysis, contrary to previous studies that reported lineages 1 and V. It was similar to the lineage that is in circulation in Senegal. There have not been many molecular studies in detail about these viruses in Nigeria because molecular studies are very expensive to conduct.
But the impression many people have is that we don’t have viruses like rift valley, zika and chikugunya in Nigeria. Can you explain?
In that study, we found antibodies for dengue, rift valley, zika, and chikugunya in the blood samples of people in these four states. Scientifically, it implies that people have, at one time or another, been exposed to those viruses. Also, several reports in the past actually showed active circulation of the five viruses in Nigeria. They are with us; the issue is that we are not doing enough to look for them. If you go to many communities in our nation, you will see a lot of symptoms that suggest these pathogens are there. But there is no screening going on, so we are not likely to know.
If every fever is not malaria until it is tested and proven to be so, does that mean that most of the cases of fever in the community may actually be due to the arboviruses you are talking about?
Yes, it is not every fever that is due to malaria. But because we are in a malaria-endemic nation, when somebody has a high fever, the first test to do is a malaria test. But if the result comes back negative, then it is a signal that it is something else that is causing the high fever, and further tests are required for other pathogens that are implicated in high fever. Unfortunately, most of the health facilities do not have the capacity to test beyond malaria. That is why we are trying, as an institute, to bridge the gap and come up with home-grown and cheap diagnostics that meet international standards and can serve the purpose.
We pray that individuals and the government buy into it so that we can have these kits spread around health facilities around the country, and people who come down with high fever and test negative for malaria can get screened straight away for other pathogens that are implicated in high fever. It will also help to reduce the spreading of these viruses, which, when at their highest level of replication, can be transferred from human to human.
From your work on the field, what is the best way for Nigeria to tackle so many emerging and reemerging diseases currently ravaging globally?
The best way to tackle any problem is to know the problem. That is the first step. That is where surveillance comes in. It will help to know what is circulating in the nation, where they are, their manifestations and what is transmitting them. Those questions need to be answered first. The next question will then be easier to solve. It is only then that we can talk about developing appropriate vaccines and diagnostic tests, since we know the strains of different microorganisms that are circulating and causing the problem in our nation. That is why surveillance is key to stemming emerging and reemerging diseases.
What do you think may likely be the next pandemic after COVID-19?
There is no scientist in the world that can tell you that this is the next pathogen that will cause a pandemic and that is the reason for surveillance to detect what is circulating in each country. Every nation must know the diseases that are endemic in the region and identify the diseases that can cause epidemics or have pandemic potential in the various communities to prevent the next pandemic from happening, and that is why surveillance is key. If we don’t do this, it will leave the world unaware.
