In this picture taken on January 18, 2022, a supervisor handles a Coviself Rapid Antigen Test (RAT) kits to self-test for the Covid-19 coronavirus during the packaging process at the Mylab Discovery Solutions manufacturing facility in Lonavla, some 90 km south-east of Mumbai.
| Punit Paranjpe | AFPNews
Premium
Why Covid-19 self-test kits are still unavailable in Kenya
Since the onset of the coronavirus pandemic, now in its third year, a trace, test and treat protocol for every detected case has been advanced by scientists and doctors as the best strategy for driving down Covid-19 cases.
In fact, in the Covid 19 strategy update released in 2020, World Health Organization (WHO) Director-General Dr Tedros Adhanom Ghebreyesus wrote: “One of the main things we’ve learned is that the faster all cases are found, tested and isolated, the harder we make it for this virus to spread. This principle will save lives and mitigate the economic impact of the pandemic.”
To control the spread of Covid-19, a PCR test came to be considered the gold standard for detecting the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus that causes infection.
It's the test travellers scramble to schedule before embarking on their journey or people who have tested positive need to stop isolating.
In other instances, some hospitals have demanded PCR tests for patients before admission while some employers have directed employees to take before returning to work after being infected with Covid-19.
Sh4,500
But a pathologist says that although PCR is the most sensitive test for Covid-19, it is not necessarily the best. This is because its availability is limited by cost, it has slow turnaround time, and requires specialised technicians and equipment. A PCR test can cost anywhere between Sh4,500 and Sh11,000.
As Covid-19 cases rose globally, there were supply chain challenges in laboratory testing kits, reagents and other materials. As such, in 2020, Kenya adopted the use of rapid antigen tests in addition to PCR tests.
Still, the country has never achieved optimum testing as most of the Covid-19 positive cases detected mostly involve patients tested in hospitals or travellers.
A PCR test may not be the best one for every situation because it requires highly skilled technical personnel and capacity and is thus limited to centralised labs, said Dr Ahmed Kalebi, a Nairobi-based consultant pathologist.
“It also has a relatively slow turnaround time, with most labs taking six to 24 hours to release results - some even longer, which limits its usefulness to quickly make a diagnosis of infection and enable isolation plus contact tracing or otherwise,” said Dr Kalebi, retired founder of the Lancet Group of Pathologists.
This has prompted a consortium of 100 organisations to urge the WHO to expedite guidelines on self-testing to allow for global access to the rapid kits.
In a letter to the UN health agency published Sunday, the consortium of civil society, clinicians and advocates called on the WHO to recommend self-testing for Covid-19, saying it will “broadly improve access to diagnostics”.
“We specifically call on WHO to expedite the finalisation and release of a self-testing guideline for SARS-CoV-2 infection that includes a strong recommendation in favour of widespread access to self-testing,” they wrote.
“We understand that the Guideline Development Process is ongoing but emphasise the urgency of making an immediate statement in favour of this important tool for Covid-19 control in the interim.”
Self-test kits are those that a patient or lay person can procure and conduct themselves and are similar to those for pregnancy, HIV and blood sugar.
While most Covid-19 self-test kits are rapid antigen tests – because they are cheap and easy to use under any circumstances or environment – Dr Kalebi said that not all of them are rapid antigen tests “as there are also available self-test PCR kits but the self-test PCR tests are fairly expensive, more technical and not as quick”.
In their letter to Dr Tedros, the consortium says that although low- and middle-income countries represent nearly 85 per cent of the global population, only 40 per cent of Covid-19 tests have been used.
“As a result, the reported average daily testing rate of high-income countries is, per capita, nearly 10 times higher than that of middle-income countries and close to 100 times higher than that of low-income countries,” the consortium argues.
Lack of adequate testing has been cited by the WHO regional officer for Africa as a reason for up to six in seven Covid-19 infections going undetected in Africa.
Self-test kits are used widely in most Western countries, including the US and the UK, where a variety of kits ranging from rapid antigen tests to self-test PCR kits.
In Kenya, however, the pharmaceutical products regulator, the Pharmacy and Poisons Board, said that it had not approved imports of any self-test kits.
Dr Kamamia Murichu, the chairperson of the Kenya Pharmaceutical Distributors Association, also reiterated that the group “is not allowing importation of self-test kits because they are creating a lot of false alarms among users”.
Dr Kalebi said he supports the consortium’s plea as the rapid antigen tests are quick, cheap and easy to use even multiple times and so are better than PCR particularly in parts of the world where PCR tests are unavailable or inaccessible and unaffordable.
Good sensitivity
“Remember PCR, because of its extremely good sensitivity, can remain positive even when someone is no longer infectious and recovering/recovered from Covid-19, whereas rapid antigen test would be positive when someone is shedding lots of virus and is infectious, which makes the rapid antigen test more useful and practical at the community level for pandemic control,” he added.
So when should one take a PCR or a rapid antigen test?
Although rapid antigen tests are cheaper, have shorter turnaround times (10 to 30 minutes after the start of the analysis) and are easier to use, PCR tests are still preferred.
That is because PCR can detect small amounts of the coronavirus' genetic material in a specimen. The test then works by amplifying or making copies of that material if any is present, according to the US Centers for Disease Control and Prevention.
PCR’s amplifying property makes it “the best in the situation where highly sensitive testing to detect low levels of the virus is required as it is more sensitive than rapid antigen test, which can miss up-to 30-50 per cent of cases, depending on the stage of infection and viral load,” explained Dr Kalebi.
He added that that is why “airlines and immigration have been insisting on PCR as rapid antigen tests can miss some cases as false negative”.
