Council bosses are urging people to "be aware" of coronavirus symptoms after tracing cases of the virus back to local businesses.
The council has told people who visited Plush hairdressers in Baglan and Neath Athletic RFC to look out for symptoms of Covid-19.
Two people who visited Plush on October 14, 15, 16, 17 and 20 have since tested positive for the virus and two people who attended Neath Athletic RFC on Saturday, October 17, later tested positive.
A Neath Port Talbot council spokesman said the TTP service traces contacts of people known to have the virus "successfully and promptly" most of the time and while working with "a daunting caseload" of 70 to 80 cases per day and more than 1,000 contacts per week.
He added: "Sometimes, however, we have to issue retrospective appeals due to the length of time it often takes for people to test positive (symptoms can take up to 14 days to develop).
“The chain of infection moves onward in time but we use these retrospective appeals to fix a time and location where the infected person was present so it alerts others who may have come into contact with them.
“Our TTP teams are working hard to protect us all during this worldwide pandemic and we thank them for the invaluable job they are doing in extremely difficult circumstances and we appeal to everyone to co- operate fully with the TTP service.”
The council advises anyone displaying coronavirus symptoms to book a test and stay at home before and after being tested. Their household members should also stay home to prevent the spread of the virus and protect the NHS.
Further advice is available at: https://www.gov.uk/get-coronavirus-test
People can also phone 01639 862757.
