A total of 2,835 inmates at two main prisons in Bangkok - the Bangkok Remand Prison and Central Women's Correctional Institution - have been found to be infected with Covid-19, Corrections Department director-general Aryut Sinthoppan said on Wednesday.
Mr Aryut revealed the figures after democracy activist Panusya Sithijirawattanakul posted on her Facebook page after being released on bail that she was infected with the virus during her stay in detention.
Ms Panusya was released on May 6 after being detained for 59 days at the Central Women's Correctional Institution.
Mr Aryut said active case finding conducted on prison officials and inmates found that 1,795 prisoners at Bangkok Remand Prison and 1,040 at the Central Women's Correctional Institution - 2,835 in total - were infected with the Covid-19 virus.
Most of them were being treated at the field hospitals set up at the two prisons or the Corrections Hospital. Others in more severe condition were admitted to other hospitals outside, he said.
"The Corrections Department has ordered all correctional facilities to set up an area for quarantine and a field hospital, with doctors and nurses on duty to provide treatment for the infected inmates.
"We also plan to inoculate all detainees. We are only waiting for an allocation of vaccines from relevant agencies," Mr Aryut said.
The Corrections Department had conducted active case finding on prison officials and detainees. Those found infected were taken out for treatment and those deemed high-risk put in quarantine.
New inmates were to be placed in quarantine for at least 21 days and they must be tested for Covid-19 twice before being sent to different zones.
He said the number of infected inmates was small when compared to the number of infections throughout the country.
According to a source at the Corrections Department, as of May 5, there were 3,238 prisoners at the Bangkok Remand Prison and 4,518 at the Central Women's Correctional Institution,
The website prisonstudies.org reports there were 307,910 people being held in Thai prisons as of April 1 this year, including pre-trial detainees. The site, run by the Institute for Crime and Justice Policy Research, quotes the "national prison administration".