The couple's son, Muhammed, announced his mother's condition this week after the couple's doctor visited them in detention.
Authorities of the detention facility where the leader of the Islamic Movement of Nigeria, Ibrahim El-Zakzaky, and his wife Zeenat, are being held say they are not aware Zeenat tested positive for coronavirus.
The couple's son, Muhammed, announced his mother's condition this week after the couple's doctor visited them in detention.
But controller of Kaduna Correctional Service, Ibrahim Maradun, said he has yet to receive test results after a sample was taken on Wednesday by officials of the Nigeria Centre for Disease Control.
He said Zeenat had been in isolation since the sample was taken, DailyTrust reports.
"As far as I am concerned, the Nigerian Center for Disease Control (NCDC) officials took her sample on Wednesday around 5 pm and I am yet to receive the result," he said.
"She has been in isolation since the day. Her personal physician has been seeing her from time to time in the company of the doctors representing the state and the correctional service."
Kaduna Corrections Command debunked reports of the infection, saying there was "no such incident in any of our facilities, as all our inmates are safe and highly protected from the virus".
It cited its efforts in March to lock down all custodial centres and halted admission of new inmates while installing gadgets to facilitate compliance with COVID-19 prevention protocols.
El-Zakzaky and his wife have been in detention since 2015 after some of his followers clashed with soldiers in Zaria, Kaduna.
El-Zakzaky is standing trial over allegations of culpable homicide, unlawful assembly, disruption of the public peace, among other charges.
Their stay at the correctional facility in Kaduna started after the couple returned from a botched medical trip in India.
News of her testing positive, released by her son, raised concern about the possible flare-up of coronavirus infections in Kaduna's correction centres.
On Friday, IMN called for the release of the couple.
Members of the movement thronged Ahmadu Bello Way in Kaduna to protest continued "illegal detention" of the El-Zakzaky's.
The group said it is deeply worried that even six days after contracting the COVID-19 while in detention at Kaduna prison, Zeenat had not been taken to any specialised hospital for such patients to receive proper medical care.
She "has been denied treatment for acute medical conditions, including severe arthritis of the knee for five years now," Ibrahim Musa, president of IMN media forum, said in a statement.
"Given her underlying medical conditions and age, her infection places her at heightened risk of severe illness and death. Sheikh Zakzaky himself suffers from many underlying conditions which put him at high risk of developing life-threatening symptoms should he contract the virus."