- 2.6 million Kenyans are Covid-19 positive.
- Nairobi and Mombasa each have 500,000 100,000 cases respectively.
- Ministry of Health figures paint a different picture, only accounting for 7,188 positive cases countrywide.
At least 2.6 million Kenyans have contracted the deadly Coronavirus disease, a medical research institute has reported.
The Kenya Medical Research Institute (KEMRI) dropped the scare on Friday, sending a wave of panic and uncertainty across the nation.
According to the research conducted by Kenya Medical Research Institute in conjunction with Wellcome Trust, at least 2.6 million people in Kenya have already contracted COVID-19, based on blood samples donated across the country and tested between April 30 and June 16, with results indicating that 500,000 people in Nairobi and about 100,000 in Mombasa, have already contracted the virus.
Scientists tested blood samples for antibodies
The scientists tested for antibodies in the blood samples obtained. These are proteins that bolster the body’s immune system by attacking foreign substances such as viruses and bacteria. Their presence in blood is a sure sign an individual has had infection before even if there were never any obvious symptoms.
“Antibody testing suggests many more Kenyans have already been exposed to Covid-19 than have been identified by surveillance activities,” Kemri says in a policy brief, released early this week.
Kenyans might have contracted the disease as early as much
This means that some may have caught the virus as early as March given that the antibodies can stay in the blood for many months.
“The large numbers of the population nothat have been exposed would lead models to predict significant numbers of severe cases and deaths. However, the county hospitals in which monitoring for pneumonia admissions is established are not seeing high numbers of admissions,” indicated the Kemri report.
The Ministry of Health figures paint a different picture, only accounting for 6000 positive cases countrywide. The prevalence of antibodies to the virus ranged from 1.1 per cent in blood donated in Uasin Gishu county to 12.4 per cent in Nairobi.
The researchers said they tested only 2,535 blood samples, and it is possible they over-estimated the number of people who have been exposed to Covid-19.
“Many more samples including sources outside blood donors are required to make confident conclusions,” they said.
Normal PCR tests on throat and nose swabs only reveal active infection and cannot reveal people who have recovered from infection.
By July 1, the government had conducted only 173,355 PCR tests, out which 6,673 turned positive.
Expert faults the sampling method
Public health specialist Dr Richard Ayah has however said that the research should be approached cautiously, adding that the Kemri results were based on convenient sampling and may not be applied on the general population.
“There is no random sampling and the sample is taken from a group of people easy to contact or to reach. In this case it was from blood donors,” he said.
“The ideal way of estimating exposure to Covid-19 in the Kenyan population would be visiting randomly selected homesteads to collect and then test blood samples. This has not been practical under current restrictions,” it said in the report.
Dr Ayah said the sample sizes are also too small for the results to be extrapolated to the wider population.
For instance, in Nairobi only 137 blood samples were tested for antibodies
“The power of study is diminished when the sample size is too small,” he said.
Dr Ayah further noted the confidence intervals was too wide. This refers to the probability that a population parameter will fall between two set values for a certain proportion of times.
Dr Ayah is the director of Science & Technology Park at the University of Nairobi and the director of the University of California at San Francisco programmes in Kenya.