During yesterday’s press conference, Prime Minister Mia Amor Mottley often made reference to the ‘R’ number as well as positivity rating when addressing Barbados’ level of COVID-19 infection.
Senator Dr Jerome Walcott subsequently provided explanations of the two terms and their significance:
‘R’ number – a tool used by epidemiologists that gives a rating to infectious organisms – for example, coronavirus – in terms of the ability of that disease to spread in a society. The ‘R’ number for COVID-19 is three – meaning that someone who has the virus can spread it to three people in a room and once they contract it, can then pass it on to three other people. He added the ideal would be for an ‘R’ factor of less than one or about 0.5. Barbados’ ‘R’ factor is currently about 1.4, which means it can spread in the society.
Positivity rate – the percentage of positive tests divided by the total number of tests conducted. The ideal is for a rating of less than four per cent. (Last week, Minister of Health Jeffrey Bostic said Barbados’ rate was averaging about five per cent.)
