The government said the deceased who died in Osogbo developed symptoms of diphtheria on 25 June and died of the infection on 7 July.
The Osun State Government has ordered the immediate activation of the emergency response centre to curb the spread of Diphtheria following the death of a six-year-old.
Governor Ademola Adeleke gave the directive in a statement on Monday by his spokesperson, Olawale Rasheed, after receiving a situation report from the state's Ministry of Health.
Mr Rasheed noted in the statement that the six-year-old who died in Osogbo developed symptoms of diphtheria on 25 June and died of the infection on 7 July.
He noted that another suspected case was said to be under testing, adding that the governor directed the contact tracing and immediate treatment of the infected residents, TheCable reports.
The Nigeria Centre for Disease Control and Prevention (NCDC) on Friday announced an outbreak of diphtheria in the Federal Capital Territory (FCT) following the first case and death of a four-year-old child in June.
NCDC also confirmed 798 diphtheria cases and 80 deaths from 33 Local Government Areas (LGAs) in eight states, including the FCT.
Osun response
The spokesperson to Mr Adeleke emphasised in the statement that the state emergency response centre be reactivated urgently.
Mr Rasheed noted that "the confirmed case at Osogbo is to be immediately followed up with contact tracing to ascertain the status of those who had been in contact with the victim", adding that emergency treatment must be available to the infected.
He wrote: "We are in touch with the National Centre for Disease Control for the exchange of information and technical support.
"I want to assure our people that proactive steps are being taken to nip in the bud any widespread escalation of the outbreak.
"Our people must be vigilant and observe precautions the Ministry of Health will soon be issuing.
"We must never forget to immunise our children and wards. Your government is on top of this medical development."
Prevalence
Diphtheria is a highly contagious infection that can cause breathing difficulties and heart problems that can be fatal, particularly in children.
According to NCDC, Kano state accounted for most of the confirmed cases, while other states are Lagos, Yobe, Katsina, Cross River, Kaduna, and Osun.
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NCDC added that the majority (71.7 per cent) of the 798 confirmed cases occurred among children aged 2 - 14 years.
Despite diphtheria being a vaccine-preventable disease, NCDC noted that 654 (82 per cent) of 798 confirmed cases of the ongoing outbreaks were unvaccinated.
The disease control centre advised parents to ensure their children are fully vaccinated against the disease with three doses of antitoxin-containing pentavalent vaccine given as part of Nigeria's childhood immunisation schedule.
It also urged healthcare workers to maintain a high index of suspicion for diphtheria.
The symptoms of diphtheria include fever, runny nose, sore throat, cough, red eyes (conjunctivitis) and neck swelling. In severe cases, NCDC said that a thick grey or white patch appears on the tonsils and, or at the back of the throat, associated with difficulty breathing.
