The World Health Organization (WHO) has warned that Africa might be headed for a much larger outbreak than current numbers are suggesting.

We've looked at the situation across the continent, and examined which countries are of most concern.
How fast is coronavirus spreading?

Michael Ryan, who leads the WHO's emergencies programme, has said: "I am very concerned right now that we are beginning to see an acceleration of [the] disease in Africa."

In terms of overall numbers, Africa currently accounts for only a small proportion of total global cases, but the acceleration in rates of infection in some countries is of increasing concern to health authorities in the region.

The proportion of cases that are from Africa rose from 2.8% in early June to 5% of all cases reported globally by mid-July.

The upward trend is starting to resemble other parts of the world that have been badly hit by the coronavirus. Most African countries are now experiencing community transmission, according to the WHO.

This is when a person gets Covid-19 without having been in contact with a known case from abroad or a confirmed domestic case.
Where are Africa's hotspots?

The two countries with the highest numbers of cases are South Africa and Egypt. They accounted for 75% of all the new cases reported by mid-July.

South Africa has the highest recorded number of total cases and reported deaths, and accounts for more than half of all the cases in Africa.

It has the fifth highest number of confirmed cases worldwide, although reported deaths appear lower compared with other countries badly hit by coronavirus.

Research from the South African Medical Research Council (SAMRC) indicates the number of people who have died from the virus could be much higher than officially reported.

It says excess deaths, which is the difference between deaths reported over a particular period and the historical average, rose by 17,000 - that's a 59% increase compared with previous years.

Gauteng province, which includes Johannesburg, has seen a steady increase in cases and accounts for more than a third of the total cases. But Western Cape province (where Cape Town is located) accounts for more than half of the deaths.

Egypt has seen case numbers rising rapidly since mid-May, but there are indications that this may now have reached a peak with recorded new infections levelling off slightly in early July.

There is also concern about what is happening in Nigeria, which is third in terms of total cases recorded so far on the continent.

It's worth stressing that some parts of the continent have seen relatively few cases, such as some areas of central and East Africa.

The Africa CDC (Centres for Disease Control and Prevention) says that five countries account for more than 75% of all the reported cases on the continent.
How many people are dying in Africa?

The reported death rate per capita has been low compared to other parts of the world, despite the poor health infrastructure in many African countries.

The WHO says this could be partly because of the relatively young population in Africa - more than 60% under the age of 25. Covid-19 is known to have a higher mortality rate for older age groups.

In terms of what proportion of people who get Covid-19 go on to die, there are ten countries with rates comparable with or higher than the most recent global average rate of 4.2%.

The top five are:

Chad (8.4%)
Liberia (6.3%)
Sudan (6.3%)
Niger (6.2%)
Burkina Faso (5%)

But Githinji Gitahi, the head of Amref Health Africa, an NGO which specialises in health matters, says the higher fatality rates could be an indication of much higher infection levels not being captured because of low levels of testing.

The fewer tests you carry out, the fewer cases you find, and so the number of deaths appears relatively high.

Different methods of recording deaths attributed to Covid-19 may also affect the number.
How much testing is done in Africa?

Ten countries account for about 80% of the total tests conducted - South Africa, Morocco, Ghana, Egypt, Ethiopia, Uganda, Mauritius, Kenya, Nigeria and Rwanda.

There are wide variations in testing rates, with South Africa doing the most and Nigeria doing relatively few, according to Our World in Data, a UK-based project which collates Covid-19 information.

By 21 July, South Africa had done about 43 tests per 1,000 people, compared to 122 in the UK and 143 in the US.

Nigeria has achieved 0.9 tests per 1,000 people, Ghana 11 and Kenya 4.

It's worth pointing out that for some African countries, it is impossible to know what exactly is happening due to a lack of any data or data being incomplete.

"We have to take the numbers with a pinch of salt," says Chiedo Nwankwor, a lecturer in African affairs at Johns Hopkins University in the US.

In Tanzania, President John Magufuli has voiced doubts about the validity of virus testing results at the national laboratory, and has allowed only limited data on infection rates and testing to be made public.

Equatorial Guinea had a row with the WHO after accusing its country representative of inflating the number of Covid-19 cases. For a while it held back its data, but has now started sharing it again.