On April 26 Chikwe Ihekweazu, head of the Nigeria Center for Disease Control, put out a desperate call on Twitter for tests that detect pieces of viral genetic material in patient samples. At that time the West African country of 196 million had tested fewer than 12,000 people for the novel coronavirus. Germany, by contrast, was testing half a million people a week. Although Ihekweazu’s initial request was answered, with companies coming forward and offering stocks of testing materials, Nigeria is still struggling to keep up with the demand for tests.
Ihekweazu’s problem mirrors that of other health officials on the continent. Tests to diagnose viral infections are key to controlling the pandemic, but African countries do not make any locally and must import them. And though these nations have money to buy test kits and reagents, they have been routinely outbid by richer ones, including the U.S. and in the European Union. Through a recent African initiative, countries there secured 90 million test kits to be shipped over the next six months. Yet that number will likely not be enough to stem the tide of COVID-19 in a continent of 1.3 billion people.
As of June 15, there were more than 173,000 confirmed COVID-19 cases in Africa, and the number continues to rise. In South Africa—both the epicenter of the pandemic on the continent and the African country with the most extensive testing regime—there are more than 50,000 confirmed cases, according to the World Health Organization. Now several African nations are trying to boost testing capacity using internal resources, with projects to set up field laboratories in remote areas in Nigeria and to develop rapid tests in Senegal and Uganda. The WHO is dubious about the efficacy of such tests, however. They could incorrectly diagnose people, who might then return to their communities and unknowingly spread the virus.
The pandemic has highlighted the fragility of the continent’s health care systems and supply chains. Medical care, education and research have long suffered from underfunding, a skills shortage and a dependence on other regions for equipment and pharmaceuticals. In response to the current crisis, African countries are mobilizing to fill the gaps as quickly as they can, such as by creating more laboratories or trying to develop new diagnostics. The African Centers for Disease Control and Prevention’s deputy director Ahmed Ogwell Ouma has said current circumstances offer these nations an opportunity to strengthen their health care. But it is unclear whether new efforts will create more robust systems or will prove too expensive to maintain in the long run. Setting up pharmaceutical manufacturing is expensive—something that the majority of African countries cannot afford—and parts of the continent lack the regulatory authorities to oversee the licensing of new products or to employ stringent quality control. “It will be too much to expect Africa to set up laboratories to manufacture [costly diagnostic tests] and then sit and wait for the next pandemic,” says Catherine Kyobutungi, executive director of the African Population and Health Research Center in Kenya. “If it is cheaper to manufacture in Belgium or China, why would you manufacture here?”
But that situation is not stopping some African researchers from trying. “For remote equatorial African settings, the need is for a low-cost, easy-to-use point-of-care diagnostic that can yield results in a short time while the patient waits,” says Misaki Wayengera, a researcher at Makerere University in Uganda. “Only rapid diagnostic tests can achieve that.” Uganda has completed about 140,000 assays so far and is selectively testing high-risk individuals. Researchers say the country cannot increase its capacity because of a lack of tests.
Wayengera and his colleagues had previously developed a rapid paper-strip assay for Ebola, and they are leading an effort to develop fast diagnostic test for the COVID-19-causing virus SARS-CoV-2. That new test involves putting a person’s nasopharyngeal swab in a tube containing chemicals that detect the virus’s surface proteins. Wayengera’s team has a small local manufacturing company called Astel Diagnostics on standby to assemble up to a million tests a week.
Researchers at Senegal’s Pasteur Institute of Dakar are chasing the same goal: a cheap and rapid diagnostic assay. They are working on a lateral-flow test, which uses a strip of paper impregnated with nanoparticles to detect viral proteins in saliva. The institute is partnering with the England-based biotechnology company Mologic to develop and validate the test. Senegal currently has about 4,800 confirmed COVID-19 cases.
The WHO does not recommend the use of rapid antigen tests, however. “Before these tests can be recommended, they must be validated in the appropriate populations and settings,” it wrote in a science advisory on April 8. “Inadequate tests may miss patients with active infection or falsely categorize patients as having the disease when they do not, further hampering disease control efforts.” In May the U.S. Food and Drug Administration granted its first emergency use authorization for a rapid antigen test.
The gold standard tests recommended by the WHO are molecular assays, such as reverse transcription polymerase chain reaction (RT-PCR). This technique uses chemicals to extract pieces of the virus’s code from patient blood samples and then converts those segments into DNA and amplifies them. So far rapid antigen tests have been found to be far less accurate than RT-PCR. But PCR tests can have problems, too, depending on the stage of a person’s disease progression.
Validating any new testing method is not a quick process: First, developers have to check their assay against a few dozen known positive and negative cases. Then they must conduct field trials of hundreds or even thousands of people to determine the test’s accuracy. Both the Senegalese and Ugandan tests are still in the first stage, and the efforts are far from ramping up manufacturing. So it is unlikely these assays will be able to plug the testing shortage in the near future.
In the grips of this shortage, Nigeria has turned to private medical laboratories that have their own testing capacity, as well as commercial networks, to procure the assays and chemicals that the government is struggling to access. The country currently has 26 public and authorized private laboratories testing for SARS-CoV-2.—and they have to service the largest population in Africa. To bolster this capacity as quickly as possible, companies are deploying custom-made sterile laboratories to outbreak hotspots.
Genomics company 54Gene has manufactured “mobile” laboratories to expand the Nigeria’s testing capacity. And the firm is equipping them with PCR tests acquired from international partners. The prefabricated lab buildings can be set up in remote areas. 54Gene has raised about $500,000 to design, build and equip the laboratories, as well as to pay the salaries of staff who run them, says Jumi Popoola, senior director of molecular genetics and operations at the company. It currently has four of these prefab labs in the nation, including one in Kano, where officials fear that the coronavirus is rampaging through the population unchecked. Though the city has a low number of confirmed COVID-19 cases, numerous people are dying of a “mysterious” illness.
It is a risk for governments to rely on private companies to test during a pandemic, says Kevin Marsh, director of the Africa Oxford Initiative and a professor of tropical medicine at the University of Oxford. Their operations are not centrally controlled, and equipment and sample-handling practices can vary from laboratory to laboratory. But as cases mount in Nigeria, it may be the country’s best option.
In the coming months, African nations will continue to rely on internationally manufactured tests—and to find innovative ways to access them. For example, the Africa Centers for Disease Control and Prevention is setting up a digital portal that will enable countries to buy medical equipment in bulk. The hope is that these economies of scale will allow the continent to succeed where individual countries have failed.
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