The moment he stepped out of school at about 5pm, Madam Tan's son, 7, started vomiting.
Her mother-in-law had just picked up the Primary 1 pupil on Jan 5, after his third day at Oasis Primary School.
He told his grandmother he had been holding it in until she had picked him up.
He continued vomiting on the way home, which was next to the school.
Madam Tan took him to KK Women's and Children's Hospital about an hour later.
He stopped vomiting only at midnight after taking some medication. He was discharged at 3am.
Madam Tan's son was one of 62 people struck down with vomiting and diarrhoea at Oasis Primary School in Punggol over the past week.
On Tuesday, Lianhe Wanbao first reported about the outbreak. That same day, according to some parents, the school sent a message to parents about the incident.
It said the school had found a number of pupils absent had symptoms of vomiting and the relevant authorities had been notified.It also mentioned they were disinfecting the school premises and conducting daily temperature taking exercises.
Madam Tan said her son vomited about six to seven times from the time he left school until midnight. He was absent from school for two days.
She said: "I was really worried about him, because he only just started school and fell sick within the first week."
When The New Paper met the mother of another two pupils outside the school, she said her daughter, who is a Primary 2 pupil there, also experienced vomiting and diarrhoea on the third day of school.
Her daughter returned to school the next day, but her son, who is in Primary 1, only went back on Jan 9.
She said: "I just want to forget about it. They were only sick for a day, so they were only mildy affected."
On Tuesday, a joint statement by the Ministry of Health, National Environment Agency, Agri-food & Veterinary Authority of Singapore and the Public Utilities Board said an inspection of the school canteen was conducted on Jan 9. There were no hygiene lapses detected during the inspection.
PUB had also conducted water quality tests on samples collected from the school on Jan 7 and found it safe for drinking.
Yesterday, the principal of Oasis Primary School, Mrs Ong-Chew Lu See, said the school had conducted a thorough cleaning of the premises followed by a disinfection of the whole school. The Student Care Centre and school buses were also disinfected daily.
Teachers looked out for pupils who were unwell and conducted daily temperature taking for pupils. Staggered recess times were introduced to prevent mass gatherings of pupils.
Mrs Ong-Chew said: "We fully understand our parents' concerns. Just like our students' parents, the school's foremost concern is similarly the well-being of our students.
"We are heartened to note that the parents whom we reached out to are reassured by the school's measures."
Parents can also reach out to teachers through the class messenger mobile application should they have any concerns.
This article was first published on Jan 19, 2017.
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