Whether it's a matter of faulty detection, climatic factors or simple fluke, the remarkably low rate of coronavirus infection in African countries, with their fragile health systems, continues to puzzle – and worry – experts.
To date, only three cases of infection have been officially recorded in Africa, one in Egypt, one in Algeria and one in Nigeria, with no deaths.
This is a remarkably small number for a continent with nearly 1.3 billion inhabitants, and barely a drop in the ocean of more than 86,000 cases and nearly 3,000 deaths recorded in some 60 countries worldwide.
Shortly after the virus appeared, specialists warned of the risks of its spreading in Africa, because of the continent’s close commercial links with Beijing and the fragility of its medical services.
“Our biggest concern continues to be the potential for Covid-19 to spread in countries with weaker health systems,” Tedros Adhanom Ghebreyesus, the head of the World Health Organization, told African Union health ministers gathered in the Ethiopian capital of Addis Ababa on February 22.
In a study published in The Lancet medical journal on the preparedness and vulnerability of African countries against the importation of Covid-19, an international team of scientists identified Algeria, Egypt and South Africa as the most likely to import new coronavirus cases into Africa, though they also have the best prepared health systems in the continent and are the least vulnerable.
As to why the epidemic is not more widespread in the continent, “nobody knows”, said Professor Thumbi Ndung’u, from the African Institute for Health Research in Durban, South Africa. “Perhaps there is simply not that much travel between Africa and China.”
But Ethiopian Airlines, the largest African airline, never suspended its flights to China since the epidemic began, and China Southern on Wednesday resumed its flights to Kenya. And, of course, people carrying coronavirus could enter the country from any of the other 60-odd countries with known cases.
Favourable climate factors have also been raised as a possibility.
“Perhaps the virus doesn’t spread in the African ecosystem, we don’t know,” said Professor Yazdan Yazdanpanah, head of the infectious diseases department at Bichat hospital in Paris.
This hypothesis was rejected by Professor Rodney Adam, who heads the infection control task force at the Aga Khan University Hospital in Nairobi, Kenya. “There is no current evidence to indicate that climate affects transmission,” he said. “While it is true that for certain infections there may be genetic differences in susceptibility...there is no current evidence to that effect for Covid-19.”
The study in The Lancet found that Nigeria, a country at moderate risk of contamination, is also one of the best-equipped in the continent to handle such an epidemic.
But the scientists had not anticipated that the first case recorded in sub-Saharan Africa would be an Italian working in the country.
Little more than a week ago, “our model was based on an epidemic concentrated in China, but since then the situation has completely changed, and the virus can now come from anywhere,” Mathias Altmann, an epidemiologist at the University of Bordeaux and one of the co-authors of the report, told FRANCE 24 on Friday. The short shelf-life of studies testify to the speed of the epidemic’s spread.
The Italian who tested positive for the coronavirus in Lagos had arrived from Milan on February 24 but had no symptoms when his plane landed. He was quarantined four days later at the Infectious Disease Hospital in Yaba. Several people from the company where he works have been contacted and officials are trying to trace other people with whom he might have had contact.
For Altmann, an expert in infectious diseases in developing countries, the fact that coronavirus appears to have entered sub-Saharan Africa through Nigeria is “actually good news”, because the country appears to be relatively well prepared for confronting the situation.
In a continent that “has had its share of epidemics and whose countries, therefore, have a huge knowledge of the field and real competence to react to this kind of situation”, Nigeria is in a very good position to confront the arrival of Covid-19, Altmann said.
“The CDC [Center for Disease Control] responsible for the entire region of West and Central Africa is located in Abuja, the capital of Nigeria, which means that their organisational standard in health matters is very high,” he added.
The country was already renowned for “succeeding to pretty quickly contain the Ebola epidemic in 2014,” Altmann points out. It took the Nigerian authorities only three months to eradicate Ebola in the country. The World Health Organization and the European Centre for Disease Prevention and Control at the time congratulated Nigeria for its reactivity and “world-class epidemiological detective work”.
But despite Nigeria’s strengths, the coronavirus pathogen represents a particular challenge, in that it is hard to detect. The virus may be present in an individual who has few or no symptoms, allowing it to spread quietly in a country where, like everywhere in Africa, there is “a shortage of equipment compared to Western countries, especially in diagnostic tools”, Altmann said.
Neighbouring countries like Chad or Niger have “less functional capacity to handle an epidemic,” Altmann said. But they also have an advantage: these are agricultural regions where people are outdoors more, “and viruses like this one prefer closed spaces and are less likely to spread in a rural setting,” he added.